Docs: record the zoom box as TASK 52 and fix the task-numbering drift (Unit: zoom docs)

The zoom feature shipped without a task record while its index rows carried the "TASK 51" label — which belongs to the webcam background effects (Remove + Blur). For an honest catalogue and handoff: - TASKS/task-52-zoom-box.md: feature provenance (creator-requested), the three 2026-10-08 corrections (loupe -> anchored capture over the full composite drawn last -> never show the dim shading), shapes, implementation map, tests, DONE. - TASKS.md: row 52 added (shipped); row 51 reworded — unblocked now that the zoom build shipped. - TASK 51 -> TASK 52 in Models/index.md, ViewModels/index.md, and the two code comments that pointed at the zoom as "TASK 51". - HANDOFF.md: pre-push readiness notes (5 commits ahead, push-safe).
Zoom: dims never shade the box — move the dim overlay above CanvasGrid (Unit: zoom shading fix)
2026-10-08 08:52:36 -07:00 · 2026-10-08 08:40:23 -07:00 · 2026-10-08 08:26:29 -07:00 · 2026-10-07 23:39:54 -07:00 · 2026-10-07 20:46:45 -07:00 · 2026-10-05 18:54:47 -07:00
232 changed files with 30511 additions and 7356 deletions
@@ -1,6 +1,10 @@
 bin/
 obj/
 Helpers/OAuthCredentials.cs
 # Bundled FFmpeg (135 MB of DLLs). Fetched once by scripts/fetch-ffmpeg.sh, which pins
 # the URL + SHA-256; the build then copies it to the output. Never committed — see the
 # script header for why the hash, not the binaries, is the audit trail.
 *.user
 *.suo
 .vs/
@@ -10,3 +14,5 @@ Helpers/OAuthCredentials.cs
 MONETIZATION.md
 MARCOM.md
 CREDENTIALS.md
 .aider*
 ffmpeg/
@@ -38,7 +38,7 @@ conventions live here and in `ai.md`.
 1. [`schema.md`](schema.md) — the memory-map conventions (what lives where, how to keep it true).
 2. [`ai.md`](ai.md) — the AI guide: architecture, patterns, decisions, current state.
-3. [`TASKS.md`](TASKS.md) — the task queue + authoritative YouTube API research.
+3. [`TASKS.md`](TASKS.md) — the task catalog (index + queue state); open items and API research facts are in [`TASKS/`](TASKS/).
 4. [`HANDOFF.md`](HANDOFF.md) — current operational state: what's in flight, landmines, next step.
 5. `<dir>/index.md` — the index for any directory you're about to touch.
@@ -26,6 +26,10 @@ public partial class App : Application
            AppLog.Write(args.Exception, "Dispatcher unhandled exception");
        AppLog.Write("App OnStartup begin");
        // Attribution (2026-09-04): every take must be traceable to the exact binary
        // that produced it — the wordmark shows the release counter (BuildStamp.Release);
        // the per-build GUID is forensic only and lands here.
        AppLog.Write($"Build {ytLive.Helpers.BuildStamp.Id} (compiled {ytLive.Helpers.BuildStamp.BuiltLocal})");
        // Velopack auto-update bootstrap — checks for updates on startup and
        // applies them (the app restarts automatically if an update is found).
@@ -9,22 +9,6 @@
                <ColumnDefinition Width="Auto"/>
            </Grid.ColumnDefinitions>
            <!-- Gear icon: far left -->
            <Button Grid.Column="0" ToolTip="Menu" Style="{StaticResource IconButton}"
                    VerticalAlignment="Center" Click="GearButton_Click">
                <Button.ContextMenu>
                    <ContextMenu DataContext="{Binding PlacementTarget.DataContext, RelativeSource={RelativeSource Self}}">
                        <MenuItem Header="App Settings" Command="{Binding OpenSettingsCommand}"/>
                        <Separator/>
                        <MenuItem Header="Report Bug" Command="{Binding OpenBugCommand}"/>
                        <MenuItem Header="Feature Request" Command="{Binding OpenFeatureCommand}"/>
                        <MenuItem Header="About" Command="{Binding OpenAboutCommand}"/>
                    </ContextMenu>
                </Button.ContextMenu>
                <Path Data="M19.14,12.94c0.04,-0.3 0.06,-0.61 0.06,-0.94c0,-0.32 -0.02,-0.64 -0.07,-0.94l2.03,-1.58c0.18,-0.14 0.23,-0.41 0.12,-0.61l-1.92,-3.32c-0.12,-0.22 -0.37,-0.29 -0.59,-0.22l-2.39,0.96c-0.5,-0.38 -1.03,-0.7 -1.62,-0.94L14.4,2.81c-0.04,-0.24 -0.24,-0.41 -0.48,-0.41h-3.84c-0.24,0 -0.43,0.17 -0.47,0.41L9.25,5.35C8.66,5.59 8.12,5.92 7.63,6.29L5.24,5.33c-0.22,-0.08 -0.47,0 -0.59,0.22L2.74,8.87C2.62,9.08 2.66,9.34 2.86,9.48l2.03,1.58C4.84,11.36 4.8,11.69 4.8,12s0.02,0.64 0.07,0.94l-2.03,1.58c-0.18,0.14 -0.23,0.41 -0.12,0.61l1.92,3.32c0.12,0.22 0.37,0.29 0.59,0.22l2.39,-0.96c0.5,0.38 1.03,0.7 1.62,0.94l0.36,2.54c0.05,0.24 0.24,0.41 0.48,0.41h3.84c0.24,0 0.44,-0.17 0.47,-0.41l0.36,-2.54c0.59,-0.24 1.13,-0.56 1.62,-0.94l2.39,0.96c0.22,0.08 0.47,0 0.59,-0.22l1.92,-3.32c0.12,-0.22 0.07,-0.47 -0.12,-0.61L19.14,12.94zM12,15.6c-1.98,0 -3.6,-1.62 -3.6,-3.6s1.62,-3.6 3.6,-3.6s3.6,1.62 3.6,3.6S13.98,15.6 12,15.6z"
                      Fill="#d0d0d0" Width="16" Height="16" Stretch="Uniform"/>
            </Button>
            <!-- Stream stats: centered under the preview pane -->
            <StackPanel Grid.Column="1" Orientation="Horizontal" HorizontalAlignment="Center" VerticalAlignment="Center">
                <TextBlock Text="Bitrate:" Style="{StaticResource YtLabel}" Margin="0,0,4,0"/>
@@ -1,4 +1,3 @@
 using System.Windows;
 using System.Windows.Controls;
 namespace ytLive.Controls;
@@ -9,14 +8,4 @@ public partial class BottomBar : UserControl
    {
        InitializeComponent();
    }
    private void GearButton_Click(object sender, RoutedEventArgs e)
    {
        if (sender is Button { ContextMenu: { } menu } button)
        {
            menu.PlacementTarget = button;
            menu.Placement = System.Windows.Controls.Primitives.PlacementMode.Bottom;
            menu.IsOpen = true;
        }
    }
 }
@@ -0,0 +1,612 @@
 <UserControl x:Class="ytLive.Controls.LeftPanel"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:Helpers="clr-namespace:ytLive.Helpers"
             xmlns:models="clr-namespace:ytLive.Models">
    <Border Background="#16213e" CornerRadius="6" Padding="12">
                <Grid>
                    <Grid.RowDefinitions>
                        <RowDefinition Height="*"/>
                    </Grid.RowDefinitions>
                    <!-- Edit mode (offline): layers + properties -->
                    <Grid Grid.Row="0" Visibility="{Binding IsEditMode, Converter={StaticResource BoolToVis}}">
                        <Grid.RowDefinitions>
                            <RowDefinition Height="Auto"/>
                            <RowDefinition Height="Auto"/>
                            <RowDefinition Height="Auto"/>
                            <RowDefinition Height="Auto"/>
                            <RowDefinition Height="Auto"/>
                            <RowDefinition Height="Auto"/>
                            <RowDefinition Height="*"/>
                        </Grid.RowDefinitions>
                        <!-- LAYERS header + Add button -->
                        <StackPanel Grid.Row="0" Orientation="Horizontal" Margin="0,8,0,0">
                            <TextBlock Text="LAYERS" Style="{StaticResource SectionHeader}" VerticalAlignment="Center"/>
                            <Button ToolTip="Add Layer" Style="{StaticResource IconButton}" Margin="4,-4,0,0"
                                Click="AddSourceButton_Click">
                            <Button.ContextMenu>
                                <ContextMenu DataContext="{Binding PlacementTarget.DataContext, RelativeSource={RelativeSource Self}}">
                                    <MenuItem Header="Webcam" Command="{Binding AddWebcamCommand}"
                                              IsEnabled="{Binding CanAddWebcam}"
                                              ToolTip="{Binding WebcamAddToolTip}"/>
                                    <MenuItem Header="Image" Command="{Binding AddImageCommand}"/>
                                    <MenuItem Header="Text" Command="{Binding AddSourceCommand}" CommandParameter="{x:Static models:SourceType.TextOverlay}"/>
                                    <MenuItem Header="Countdown" Command="{Binding AddSourceCommand}" CommandParameter="{x:Static models:SourceType.Countdown}"
                                              Visibility="{Binding IsCountdownAvailable, Converter={StaticResource BoolToVis}}"
                                              ToolTip="Timer overlay — Starting and BRB screens only"/>
                                    <MenuItem Header="Web Resource" Command="{Binding AddSourceCommand}" CommandParameter="{x:Static models:SourceType.WebSource}"
                                              ToolTip="Embedded web page — set URI in Properties panel"/>
                                    <MenuItem Header="YouTube Chat" Command="{Binding AddSourceCommand}" CommandParameter="{x:Static models:SourceType.ChatBox}"
                                              IsEnabled="{Binding CanAddYouTubeChat}"
                                              ToolTip="One chat layer at a time — it's already in your stream"/>
                                    <MenuItem Header="Stream Alerts" Command="{Binding AddSourceCommand}" CommandParameter="{x:Static models:SourceType.AlertBox}"
                                              IsEnabled="{Binding CanAddAlerts}"
                                              ToolTip="Celebration zone for Super Chat &amp; memberships — one alert layer at a time"/>
                                </ContextMenu>
                            </Button.ContextMenu>
                            <Path Data="M12,4 L12,20 M4,12 L20,12" Stroke="#e94560" StrokeThickness="2"
                                  Width="14" Height="14" Stretch="Uniform"/>
                        </Button>
                    </StackPanel>
                    <Helpers:FocusPreservingListBox x:Name="SourceList" Grid.Row="1" Background="Transparent" BorderThickness="0"
                             ItemsSource="{Binding StagedScene.Elements}"
                             SelectedItem="{Binding SelectedElement, Mode=TwoWay}"
                             PreviewMouseLeftButtonDown="List_PreviewMouseLeftButtonDown"
                             PreviewMouseMove="List_PreviewMouseMove"
                             PreviewMouseLeftButtonUp="List_PreviewMouseLeftButtonUp"
                             Foreground="#e0e0e0" FontSize="13">
                        <Helpers:FocusPreservingListBox.ItemContainerStyle>
                            <Style TargetType="ListBoxItem" BasedOn="{StaticResource YtListBoxItem}">
                                <Setter Property="HorizontalContentAlignment" Value="Stretch"/>
                                <Style.Triggers>
                                    <DataTrigger Binding="{Binding IsVisible}" Value="False">
                                        <Setter Property="Opacity" Value="0.45"/>
                                    </DataTrigger>
                                    <!-- The transient zoom layer has no editing UI — never
                                         show it as a layer row (TASK 51). -->
                                    <DataTrigger Binding="{Binding IsZoomLayer}" Value="True">
                                        <Setter Property="Visibility" Value="Collapsed"/>
                                    </DataTrigger>
                                </Style.Triggers>
                            </Style>
                        </Helpers:FocusPreservingListBox.ItemContainerStyle>
                        <ListBox.ItemTemplate>
                            <DataTemplate>
                                <Grid Margin="0,2"
                                      Tag="{Binding DataContext.CanChangeBackground, RelativeSource={RelativeSource AncestorType=Window}}">
                                    <Grid.ColumnDefinitions>
                                        <ColumnDefinition Width="*"/>
                                        <ColumnDefinition Width="Auto"/>
                                        <ColumnDefinition Width="Auto"/>
                                        <ColumnDefinition Width="Auto"/>
                                    </Grid.ColumnDefinitions>
                                    <Grid.ContextMenu>
                                        <ContextMenu DataContext="{Binding PlacementTarget.DataContext, RelativeSource={RelativeSource Self}}">
                                            <MenuItem Header="Change Capture…" Click="BackgroundMenu_ChangeCapture">
                                                <MenuItem.Visibility>
                                                    <MultiBinding Converter="{StaticResource AllTrueToVis}">
                                                        <Binding Path="IsBackground"/>
                                                        <Binding Path="PlacementTarget.Tag" RelativeSource="{RelativeSource AncestorType={x:Type ContextMenu}}"/>
                                                    </MultiBinding>
                                                </MenuItem.Visibility>
                                            </MenuItem>
                                            <MenuItem Header="Refresh Capture" Click="BackgroundMenu_RefreshCapture">
                                                <MenuItem.Visibility>
                                                    <MultiBinding Converter="{StaticResource AllTrueToVis}">
                                                        <Binding Path="IsBackground"/>
                                                        <Binding Path="PlacementTarget.Tag" RelativeSource="{RelativeSource AncestorType={x:Type ContextMenu}}"/>
                                                    </MultiBinding>
                                                </MenuItem.Visibility>
                                            </MenuItem>
                                            <MenuItem Header="Capture Window…"
                                                      ItemsSource="{Binding DataContext.OpenWindows, RelativeSource={RelativeSource AncestorType=Window}}">
                                                <MenuItem.Visibility>
                                                    <MultiBinding Converter="{StaticResource AllTrueToVis}">
                                                        <Binding Path="IsBackground"/>
                                                        <Binding Path="PlacementTarget.Tag" RelativeSource="{RelativeSource AncestorType={x:Type ContextMenu}}"/>
                                                    </MultiBinding>
                                                </MenuItem.Visibility>
                                                <MenuItem.ItemContainerStyle>
                                                    <Style TargetType="MenuItem">
                                                        <Setter Property="Header" Value="{Binding Label}"/>
                                                        <Setter Property="Command"
                                                                Value="{Binding DataContext.CaptureWindowCommand, RelativeSource={RelativeSource AncestorType=Window}}"/>
                                                        <Setter Property="CommandParameter" Value="{Binding}"/>
                                                    </Style>
                                                </MenuItem.ItemContainerStyle>
                                            </MenuItem>
                                            <MenuItem Header="Refresh Window List" Click="BackgroundMenu_RefreshWindowList">
                                                <MenuItem.Visibility>
                                                    <MultiBinding Converter="{StaticResource AllTrueToVis}">
                                                        <Binding Path="IsBackground"/>
                                                        <Binding Path="PlacementTarget.Tag" RelativeSource="{RelativeSource AncestorType={x:Type ContextMenu}}"/>
                                                    </MultiBinding>
                                                </MenuItem.Visibility>
                                            </MenuItem>
                                            <Separator>
                                                <Separator.Visibility>
                                                    <MultiBinding Converter="{StaticResource AllTrueToVis}">
                                                        <Binding Path="IsBackground"/>
                                                        <Binding Path="PlacementTarget.Tag" RelativeSource="{RelativeSource AncestorType={x:Type ContextMenu}}"/>
                                                    </MultiBinding>
                                                </Separator.Visibility>
                                            </Separator>
                                            <MenuItem Header="Remove Layer" Click="SourceMenu_Remove"
                                                      Visibility="{Binding IsBackground, Converter={StaticResource InverseBoolToVis}}"/>
                                        </ContextMenu>
                                    </Grid.ContextMenu>
                                    <TextBlock Grid.Column="0" Text="{Binding Name}" VerticalAlignment="Center"
                                               Padding="4,2" TextTrimming="CharacterEllipsis">
                                        <TextBlock.Style>
                                            <Style TargetType="TextBlock">
                                                <Setter Property="Visibility" Value="Visible"/>
                                                <Style.Triggers>
                                                    <DataTrigger Binding="{Binding IsEditing}" Value="True">
                                                        <Setter Property="Visibility" Value="Collapsed"/>
                                                    </DataTrigger>
                                                </Style.Triggers>
                                            </Style>
                                        </TextBlock.Style>
                                    </TextBlock>
                                    <TextBox Grid.Column="0" Text="{Binding Name, UpdateSourceTrigger=PropertyChanged}"
                                             Background="#0f3460" Foreground="#e0e0e0" BorderThickness="0"
                                             Padding="4,2" VerticalContentAlignment="Center"
                                             IsVisibleChanged="SourceNameBox_IsVisibleChanged"
                                             KeyDown="SourceNameBox_KeyDown" LostFocus="SourceNameBox_LostFocus">
                                        <TextBox.Style>
                                            <Style TargetType="TextBox">
                                                <Setter Property="Visibility" Value="Collapsed"/>
                                                <Style.Triggers>
                                                    <DataTrigger Binding="{Binding IsEditing}" Value="True">
                                                        <Setter Property="Visibility" Value="Visible"/>
                                                    </DataTrigger>
                                                </Style.Triggers>
                                            </Style>
                                        </TextBox.Style>
                                    </TextBox>
                                    <Button Grid.Column="1" ToolTip="Edit Layer Name"
                                            Command="{Binding DataContext.EditElementCommand, RelativeSource={RelativeSource AncestorType=ListBox}}"
                                            CommandParameter="{Binding}" Style="{StaticResource IconButton}">
                                        <Path Data="M3,17.25V21h3.75L17.81,9.94l-3.75,-3.75L3,17.25zM20.71,7.04c0.39,-0.39 0.39,-1.02 0,-1.41l-2.34,-2.34c-0.39,-0.39 -1.02,-0.39 -1.41,0l-1.83,1.83 3.75,3.75 1.83,-1.83z"
                                              Fill="#d0d0d0" Width="13" Height="13" Stretch="Uniform"/>
                                    </Button>
                                    <Button Grid.Column="2" Style="{StaticResource EyeButton}"
                                            Command="{Binding DataContext.ToggleElementVisibilityCommand, RelativeSource={RelativeSource AncestorType=ListBox}}"
                                            CommandParameter="{Binding}">
                                        <Path Style="{StaticResource EyeIconStyle}" Fill="#d0d0d0"
                                              Width="13" Height="13" Stretch="Uniform"/>
                                    </Button>
                                    <Button Grid.Column="3" ToolTip="Remove Layer"
                                            Command="{Binding DataContext.RemoveSourceCommand, RelativeSource={RelativeSource AncestorType=ListBox}}"
                                            CommandParameter="{Binding}" Style="{StaticResource IconButton}"
                                            Visibility="{Binding IsBackground, Converter={StaticResource HiddenBoolToVis}}">
                                        <Path Data="M6,19c0,1.1 0.9,2 2,2h8c1.1,0 2,-0.9 2,-2V7H6v12zM19,4h-3.5l-1,-1h-5l-1,1H5v2h14V4z"
                                              Fill="#d0d0d0" Width="13" Height="13" Stretch="Uniform"/>
                                    </Button>
                                </Grid>
                            </DataTemplate>
                        </ListBox.ItemTemplate>
                    </Helpers:FocusPreservingListBox>
                            <TextBlock Grid.Row="2" Text="No layers yet" Foreground="#555" FontSize="12"
                               HorizontalAlignment="Center" VerticalAlignment="Center"
                               Visibility="{Binding ShowSourcesEmptyHint, Converter={StaticResource BoolToVis}}"/>
                    <!-- Resource alert: pinned to the bottom of the Layers panel.
                         Red when a required resource (the one-and-only webcam)
                         could not be locked; persists and re-polls until resolved. -->
                    <Border Grid.Row="3" Margin="0,8,0,0" Padding="8,6" CornerRadius="4"
                            Background="#3a1216" BorderBrush="#e94560" BorderThickness="1"
                            Visibility="{Binding WebcamLockAlert, Converter={StaticResource NotNullToVis}}">
                        <StackPanel>
                            <TextBlock Text="{Binding WebcamLockAlert}" Foreground="#ffb4b4" FontSize="11"
                                       TextWrapping="Wrap"/>
                            <Button Content="Retry" Command="{Binding RetryWebcamLockCommand}"
                                    Style="{StaticResource YtButtonSecondary}" Padding="10,2"
                                    HorizontalAlignment="Right" Margin="0,6,0,0"/>
                        </StackPanel>
                    </Border>
                    <!-- ELEMENTS panel: per-element config beneath Sources.
                         Collapses entirely when no element is selected. -->
                    <Rectangle Grid.Row="4" Height="1" Fill="#2c3a5c" Margin="0,10,0,2"
                               Visibility="{Binding SelectedElement, Converter={StaticResource NotNullToVis}}"/>
                    <StackPanel Grid.Row="5" Orientation="Horizontal" Margin="0,8,0,0"
                                Visibility="{Binding SelectedElement, Converter={StaticResource NotNullToVis}}">
                        <TextBlock Text="PROPERTIES" Style="{StaticResource SectionHeader}" VerticalAlignment="Center"/>
                    </StackPanel>
                    <ScrollViewer x:Name="ElementsScrollViewer" Grid.Row="6" VerticalScrollBarVisibility="Auto" Background="Transparent"
                                  Visibility="{Binding SelectedElement, Converter={StaticResource NotNullToVis}}">
                        <StackPanel x:Name="ElementsPanel" Margin="0,4,0,0">
                            <!-- Opacity + mirror/shape (draggable elements: image, webcam) -->
                            <StackPanel Visibility="{Binding SelectedElement.IsDraggable, Converter={StaticResource BoolToVis}}" Margin="0,0,0,8">
                                <StackPanel Visibility="{Binding SelectedElement.IsChatBox, Converter={StaticResource InverseBoolToVis}}">
                                    <TextBlock Text="Opacity" Foreground="#a0a0b0" FontSize="11" Margin="0,0,0,2"/>
                                    <DockPanel Margin="0,0,0,6">
                                        <TextBlock x:Name="OpacityValueText" Text="100%" Foreground="#a0a0b0" FontSize="11"
                                                   DockPanel.Dock="Right" VerticalAlignment="Center" Margin="8,0,0,0" Width="32"/>
                                        <Slider x:Name="OpacitySlider" Width="120" Minimum="0" Maximum="1"
                                                Value="{Binding SelectedElement.Opacity, Mode=TwoWay}"
                                                ValueChanged="OpacitySlider_ValueChanged" VerticalAlignment="Center"/>
                                    </DockPanel>
                                </StackPanel>
                                <StackPanel Orientation="Horizontal" Margin="0,0,0,4"
                                            Visibility="{Binding IsWebcamSelected, Converter={StaticResource BoolToVis}}">
                                    <Button Content="{Binding SelectedElement.MirrorButtonText}"
                                            Style="{StaticResource YtButtonSecondary}" Padding="10,4"
                                            Click="MirrorButton_Click"/>
                                    <Button Content="{Binding SelectedElement.ShapeButtonText}"
                                            Style="{StaticResource YtButtonSecondary}" Padding="10,4"
                                            Margin="8,0,0,0" Click="ShapeButton_Click"/>
                                </StackPanel>
                                <TextBlock Text="Drag to move · drag the corner dot to resize"
                                           Foreground="#a0a0b0" FontSize="10" Margin="0,2,0,0"/>
                            </StackPanel>
                            <!-- Webcam border config -->
                            <StackPanel Visibility="{Binding SelectedElement.IsWebcam, Converter={StaticResource BoolToVis}}" Margin="0,0,0,8">
                                <TextBlock Text="Border Color" Foreground="#a0a0b0" FontSize="11" Margin="0,0,0,2"/>
                                <DockPanel Margin="0,0,0,6">
                                    <Button DockPanel.Dock="Right" Content="..." Width="24" Height="24"
                                            Click="WebcamBorderColorPicker_Click" Margin="4,0,0,0"
                                            ToolTip="Pick color"/>
                                    <TextBox Text="{Binding SelectedElement.BorderColor, UpdateSourceTrigger=PropertyChanged}"
                                             Background="#0f3460" Foreground="#e0d0e0" BorderThickness="1"
                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="12"
                                             MaxLength="7" ToolTip="#RRGGBB"/>
                                </DockPanel>
                                <TextBlock Text="Border Thickness" Foreground="#a0a0b0" FontSize="11" Margin="0,0,0,2"/>
                                <DockPanel Margin="0,0,0,6">
                                    <Button DockPanel.Dock="Right" Style="{StaticResource IconButton}"
                                            Width="22" Height="22" Margin="4,0,0,0"
                                            Click="WebcamBorderAccept_Click">
                                        <Path Data="M4,9 L8,14 L16,4" Stroke="#22c55e" StrokeThickness="2"
                                              Width="14" Height="14" Stretch="Uniform"/>
                                    </Button>
                                    <Button DockPanel.Dock="Right" Style="{StaticResource IconButton}"
                                            Width="22" Height="22" ToolTip="Revert"
                                            Click="WebcamBorderRevert_Click" Margin="4,0,0,0">
                                        <Path Data="M5,5 L15,15 M15,5 L5,15" Stroke="#e94560" StrokeThickness="2"
                                              Width="14" Height="14" Stretch="Uniform"/>
                                    </Button>
                                    <Slider DockPanel.Dock="Left" Width="120" Minimum="0" Maximum="10"
                                            Value="{Binding SelectedElement.BorderWidth, Mode=TwoWay}"
                                            VerticalAlignment="Center" TickFrequency="1" IsSnapToTickEnabled="True"/>
                                    <TextBlock Text="{Binding SelectedElement.BorderWidth}" Foreground="#a0a0b0" FontSize="11"
                                               VerticalAlignment="Center" Margin="8,0,0,0" Width="20"/>
                                </DockPanel>
                            </StackPanel>
                            <!-- Countdown config -->
                            <StackPanel Visibility="{Binding SelectedElement.IsCountdown, Converter={StaticResource BoolToVis}}" Margin="0,0,0,8">
                                <TextBlock Text="Timer (minutes)" Foreground="#a0a0b0" FontSize="11" Margin="0,0,0,2"/>
                                <DockPanel Margin="0,0,0,6">
                                    <Button DockPanel.Dock="Right" Style="{StaticResource IconButton}"
                                            Width="22" Height="22" Margin="4,0,0,0"
                                            Click="CountdownAccept_Click">
                                        <Path Data="M4,9 L8,14 L16,4" Stroke="#22c55e" StrokeThickness="2"
                                              Width="14" Height="14" Stretch="Uniform"/>
                                    </Button>
                                    <Button DockPanel.Dock="Right" Style="{StaticResource IconButton}"
                                            Width="22" Height="22" ToolTip="Revert"
                                            Click="CountdownRevert_Click" Margin="4,0,0,0">
                                        <Path Data="M5,5 L15,15 M15,5 L5,15" Stroke="#e94560" StrokeThickness="2"
                                              Width="14" Height="14" Stretch="Uniform"/>
                                    </Button>
                                    <Slider DockPanel.Dock="Left" Width="120" Minimum="1" Maximum="60"
                                            Value="{Binding SelectedElement.TimerMinutes, Mode=TwoWay}"
                                            VerticalAlignment="Center" TickFrequency="1" IsSnapToTickEnabled="True"/>
                                    <TextBlock Text="{Binding SelectedElement.TimerMinutes}" Foreground="#a0a0b0" FontSize="11"
                                               VerticalAlignment="Center" Margin="8,0,0,0" Width="20"/>
                                </DockPanel>
                            </StackPanel>
                            <!-- Web source config -->
                            <StackPanel Visibility="{Binding SelectedElement.IsWebSource, Converter={StaticResource BoolToVis}}" Margin="0,0,0,8">
                                <TextBlock Text="Geometry" Foreground="#a0a0b0" FontSize="11" FontWeight="SemiBold" Margin="0,0,0,4"/>
                                <DockPanel Margin="0,0,0,4">
                                    <TextBlock DockPanel.Dock="Left" Text="X" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="16"/>
                                    <TextBox Text="{Binding SelectedElement.X, UpdateSourceTrigger=PropertyChanged, StringFormat=F0}"
                                             Background="#0f3460" Foreground="#e0d0e0" BorderThickness="1"
                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="12"/>
                                    <TextBlock DockPanel.Dock="Left" Text="  Y" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="20" Margin="8,0,0,0"/>
                                    <TextBox Text="{Binding SelectedElement.Y, UpdateSourceTrigger=PropertyChanged, StringFormat=F0}"
                                             Background="#0f3460" Foreground="#e0d0e0" BorderThickness="1"
                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="12"/>
                                </DockPanel>
                                <DockPanel Margin="0,0,0,4">
                                    <TextBlock DockPanel.Dock="Left" Text="W" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="16"/>
                                    <TextBox Text="{Binding SelectedElement.Width, UpdateSourceTrigger=PropertyChanged, StringFormat=F0}"
                                             Background="#0f3460" Foreground="#e0d0e0" BorderThickness="1"
                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="12"/>
                                    <TextBlock DockPanel.Dock="Left" Text="  H" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="20" Margin="8,0,0,0"/>
                                    <TextBox Text="{Binding SelectedElement.Height, UpdateSourceTrigger=PropertyChanged, StringFormat=F0}"
                                             Background="#0f3460" Foreground="#e0d0e0" BorderThickness="1"
                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="12"/>
                                </DockPanel>
                                <TextBlock Text="URI" Foreground="#a0a0b0" FontSize="11" Margin="0,0,0,2"/>
                                <DockPanel>
                                    <Button DockPanel.Dock="Right" Style="{StaticResource IconButton}"
                                            Width="22" Height="22" Margin="4,0,0,0" IsTabStop="False"
                                            Click="WebAccept_Click">
                                        <Path Data="M4,9 L8,14 L16,4" Stroke="#22c55e" StrokeThickness="2"
                                              Width="14" Height="14" Stretch="Uniform"/>
                                    </Button>
                                    <Button DockPanel.Dock="Right" Style="{StaticResource IconButton}"
                                            Width="22" Height="22" ToolTip="Revert" IsTabStop="False"
                                            Click="WebRevert_Click" Margin="4,0,0,0">
                                        <Path Data="M5,5 L15,15 M15,5 L5,15" Stroke="#e94560" StrokeThickness="2"
                                              Width="14" Height="14" Stretch="Uniform"/>
                                    </Button>
                                    <TextBox Text="{Binding SelectedElement.WebUri, UpdateSourceTrigger=PropertyChanged}"
                                             Background="#0f3460" Foreground="#e0d0e0" BorderThickness="1"
                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="12"
                                             ToolTip="https://example.com"/>
                                </DockPanel>
                            </StackPanel>
                            <!-- Chat box config -->
                            <StackPanel Visibility="{Binding SelectedElement.IsChatBox, Converter={StaticResource BoolToVis}}" Margin="0,0,0,8">
                                <TextBlock Text="Chat Overlay" Foreground="#a0a0b0" FontSize="11" FontWeight="SemiBold" Margin="0,0,0,6"/>
                                <!-- Font Size -->
                                <DockPanel Margin="0,0,0,4">
                                    <TextBlock DockPanel.Dock="Left" Text="Font Size" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="70"/>
                                    <Slider x:Name="ChatFontSizeSlider" Width="120" Minimum="8" Maximum="72" TickFrequency="2" IsSnapToTickEnabled="True"
                                            Value="{Binding SelectedElement.ChatFontSize, Mode=TwoWay}"
                                            VerticalAlignment="Center"/>
                                    <TextBlock DockPanel.Dock="Right" Text="{Binding SelectedElement.ChatFontSize, StringFormat={}{0:0}}" Foreground="#e0e0e0" FontSize="11" Margin="6,0,0,0" VerticalAlignment="Center" Width="24"/>
                                </DockPanel>
                                <!-- Font Family -->
                                <DockPanel Margin="0,0,0,4">
                                    <TextBlock DockPanel.Dock="Left" Text="Font" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="70"/>
                                    <ComboBox SelectedValue="{Binding SelectedElement.ChatFontFamily, Mode=TwoWay}"
                                              SelectedValuePath="Content"
                                              Background="#0f3460" Foreground="#e0e0e0" FontSize="11"
                                              Width="140" VerticalAlignment="Center">
                                        <ComboBoxItem Content="Segoe UI"/>
                                        <ComboBoxItem Content="Arial"/>
                                        <ComboBoxItem Content="Consolas"/>
                                        <ComboBoxItem Content="Courier New"/>
                                        <ComboBoxItem Content="Comic Sans MS"/>
                                        <ComboBoxItem Content="Mouse Memoirs"/>
                                    </ComboBox>
                                </DockPanel>
                                <!-- Font Color -->
                                <DockPanel Margin="0,0,0,4">
                                    <TextBlock DockPanel.Dock="Left" Text="Font Color" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="70"/>
                                    <TextBox Text="{Binding SelectedElement.ChatFontColor, UpdateSourceTrigger=PropertyChanged}"
                                             Background="#0f3460" Foreground="#e0e0e0" BorderThickness="1"
                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="11" Width="80"/>
                                </DockPanel>
                                <!-- Member Color -->
                                <DockPanel Margin="0,0,0,4">
                                    <TextBlock DockPanel.Dock="Left" Text="Member" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="70"/>
                                    <TextBox Text="{Binding SelectedElement.ChatMemberColor, UpdateSourceTrigger=PropertyChanged}"
                                             Background="#0f3460" Foreground="#e0e0e0" BorderThickness="1"
                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="11" Width="80"/>
                                </DockPanel>
                                <!-- Super Chat Color -->
                                <DockPanel Margin="0,0,0,4">
                                    <TextBlock DockPanel.Dock="Left" Text="Super Chat" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="70"/>
                                    <TextBox Text="{Binding SelectedElement.ChatSuperChatColor, UpdateSourceTrigger=PropertyChanged}"
                                             Background="#0f3460" Foreground="#e0e0e0" BorderThickness="1"
                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="11" Width="80"/>
                                </DockPanel>
                                <!-- Max Messages -->
                                <DockPanel Margin="0,0,0,4">
                                    <TextBlock DockPanel.Dock="Left" Text="Max Msgs" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="70"/>
                                    <Slider x:Name="ChatMaxMsgsSlider" Width="120" Minimum="1" Maximum="20" TickFrequency="1" IsSnapToTickEnabled="True"
                                            Value="{Binding SelectedElement.ChatMaxMessages, Mode=TwoWay}"
                                            VerticalAlignment="Center"/>
                                    <TextBlock DockPanel.Dock="Right" Text="{Binding SelectedElement.ChatMaxMessages}" Foreground="#e0e0e0" FontSize="11" Margin="6,0,0,0" VerticalAlignment="Center" Width="24"/>
                                </DockPanel>
                                <!-- Background Color -->
                                <DockPanel Margin="0,0,0,4">
                                    <TextBlock DockPanel.Dock="Left" Text="Background" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="70"/>
                                    <TextBox Text="{Binding SelectedElement.ChatBackgroundColor, UpdateSourceTrigger=PropertyChanged}"
                                             Background="#0f3460" Foreground="#e0e0e0" BorderThickness="1"
                                             BorderBrush="#2c3a5c" Padding="4,2" FontSize="11" Width="80"/>
                                </DockPanel>
                                <!-- Background Opacity -->
                                <DockPanel Margin="0,0,0,4">
                                    <TextBlock DockPanel.Dock="Left" Text="Bg Opacity" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="70"/>
                                    <Slider x:Name="ChatBgOpacitySlider" Width="120" Minimum="0" Maximum="1"
                                            Value="{Binding SelectedElement.ChatBackgroundOpacity, Mode=TwoWay}"
                                            VerticalAlignment="Center"/>
                                    <TextBlock DockPanel.Dock="Right" Text="{Binding SelectedElement.ChatBackgroundOpacity, StringFormat={}{0:0%}}" Foreground="#e0e0e0" FontSize="11" Margin="6,0,0,0" VerticalAlignment="Center" Width="32"/>
                                </DockPanel>
                                <!-- Fade After (seconds) -->
                                <DockPanel Margin="0,0,0,4">
                                    <TextBlock DockPanel.Dock="Left" Text="Fade After" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="70"/>
                                    <Slider x:Name="ChatFadeSlider" Width="120" Minimum="0" Maximum="60" TickFrequency="5" IsSnapToTickEnabled="True"
                                            Value="{Binding SelectedElement.ChatFadeSeconds, Mode=TwoWay}"
                                            VerticalAlignment="Center"/>
                                    <TextBlock DockPanel.Dock="Right" Text="{Binding SelectedElement.ChatFadeSeconds, StringFormat='{}{0}s'}" Foreground="#e0e0e0" FontSize="11" Margin="6,0,0,0" VerticalAlignment="Center" Width="28"/>
                                </DockPanel>
                                <!-- Toggles -->
                                <CheckBox Content="Show timestamps" Foreground="#a0a0b0" FontSize="11" Margin="0,4,0,2"
                                          IsChecked="{Binding SelectedElement.ChatShowTimestamps, Mode=TwoWay}"/>
                                <CheckBox Content="Show badges" Foreground="#a0a0b0" FontSize="11" Margin="0,0,0,2"
                                          IsChecked="{Binding SelectedElement.ChatShowBadges, Mode=TwoWay}"/>
                            </StackPanel>
                            <!-- Stream Alerts config -->
                            <StackPanel Visibility="{Binding SelectedElement.IsAlertBox, Converter={StaticResource BoolToVis}}" Margin="0,0,0,8">
                                <TextBlock Text="Stream Alerts" Foreground="#a0a0b0" FontSize="11" FontWeight="SemiBold" Margin="0,0,0,6"/>
                                <TextBlock Text="The built-in clip plays on every alert (Super Chat, membership…) unless a custom video is picked."
                                           Foreground="#888" FontSize="10" TextWrapping="Wrap" Margin="0,0,0,6"/>
                                <DockPanel Margin="0,0,0,4">
                                    <TextBlock DockPanel.Dock="Left" Text="Built-in video" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="84"/>
                                    <ToggleButton Style="{StaticResource PillToggle}"
                                                  IsChecked="{Binding SelectedElement.AlertUseDefaultVideo, Mode=TwoWay}"
                                                  HorizontalAlignment="Left"/>
                                </DockPanel>
                                <Grid Margin="0,0,0,4"
                                      Visibility="{Binding SelectedElement.AlertUseDefaultVideo, Converter={StaticResource InverseBoolToVis}}">
                                    <Grid.ColumnDefinitions>
                                        <ColumnDefinition Width="*"/>
                                        <ColumnDefinition Width="Auto"/>
                                    </Grid.ColumnDefinitions>
                                    <TextBox Grid.Column="0" Text="{Binding SelectedElement.AlertVideoPath, Mode=OneWay}"
                                             IsReadOnly="True" Background="#0f3460" Foreground="#a0a0b0"
                                             FontSize="11" VerticalAlignment="Center"/>
                                    <Button Grid.Column="1" Content="Browse…" Command="{Binding BrowseAlertVideoCommand}"
                                            CommandParameter="{Binding SelectedElement}" Style="{StaticResource YtButtonSecondary}"
                                            Margin="4,0,0,0" Padding="8,2"/>
                                </Grid>
                                <Button Content="Reset to built-in" Command="{Binding ResetAlertVideoCommand}"
                                        CommandParameter="{Binding SelectedElement}" Style="{StaticResource YtButtonSecondary}"
                                        HorizontalAlignment="Left" Padding="8,2" Margin="0,0,4,0"/>
                                <TextBlock Text="Custom clips are referenced from disk — never stored in the layout."
                                           Foreground="#888" FontSize="10" TextWrapping="Wrap" Margin="0,4,0,6"/>
                                <DockPanel Margin="0,0,0,4">
                                    <TextBlock DockPanel.Dock="Left" Text="Message ticker" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="84"/>
                                    <ToggleButton Style="{StaticResource PillToggle}"
                                                  IsChecked="{Binding SelectedElement.AlertShowTicker, Mode=TwoWay}"
                                                  HorizontalAlignment="Left"/>
                                </DockPanel>
                                <!-- Announcement display: scroll (marquee), flash (pulse) or
                                     solid (still). Inline items, not a bound ItemsSource —
                                     same shape as the chat Font selector above. -->
                                <DockPanel Margin="0,0,0,4">
                                    <TextBlock DockPanel.Dock="Left" Text="Display" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="84"/>
                                    <ComboBox SelectedValue="{Binding SelectedElement.AlertDisplayMethod, Mode=TwoWay}"
                                              SelectedValuePath="Tag"
                                              Background="#0f3460" Foreground="#e0e0e0" FontSize="11"
                                              Width="140" VerticalAlignment="Center">
                                        <ComboBoxItem Content="Scroll" Tag="TickerScroll"/>
                                        <ComboBoxItem Content="Flash" Tag="Flash"/>
                                        <ComboBoxItem Content="Solid" Tag="Solid"/>
                                    </ComboBox>
                                </DockPanel>
                                <DockPanel Margin="0,0,0,4">
                                    <TextBlock DockPanel.Dock="Left" Text="Volume" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center" Width="84"/>
                                    <Slider Width="120" Minimum="0" Maximum="1"
                                            Value="{Binding SelectedElement.AlertVideoVolume, Mode=TwoWay}"
                                            VerticalAlignment="Center"/>
                                    <TextBlock DockPanel.Dock="Right" Text="{Binding SelectedElement.AlertVideoVolume, StringFormat={}{0:0%}}" Foreground="#e0e0e0" FontSize="11" Margin="6,0,0,0" VerticalAlignment="Center" Width="32"/>
                                </DockPanel>
                            </StackPanel>
                            <!-- Background properties -->
                            <StackPanel Margin="0,8,0,0"
                                        Visibility="{Binding SelectedElement.IsBackground, Converter={StaticResource BoolToVis}}">
                                <TextBlock Text="Background" Style="{StaticResource SubHeader}"/>
                                <StackPanel Margin="4,0,0,0">
                                    <StackPanel Orientation="Horizontal" Margin="0,0,0,8">
                                        <TextBlock Text="Use default background:" Foreground="#a0a0b0" FontSize="11" VerticalAlignment="Center"/>
                                        <ToggleButton Style="{StaticResource PillToggle}"
                                                      IsChecked="{Binding SelectedElement.UseDefaultBackground, Mode=TwoWay}"
                                                      Margin="8,0,0,0"/>
                                    </StackPanel>
                                    <Grid Margin="0,0,0,4"
                                          Visibility="{Binding SelectedElement.UseDefaultBackground, Converter={StaticResource InverseBoolToVis}}">
                                        <Grid.ColumnDefinitions>
                                            <ColumnDefinition Width="*"/>
                                            <ColumnDefinition Width="Auto"/>
                                        </Grid.ColumnDefinitions>
                                        <TextBox Grid.Column="0" Text="{Binding SelectedElement.CustomBackgroundPath, Mode=OneWay}"
                                                  IsReadOnly="True" Background="#0f3460" Foreground="#a0a0b0"
                                                  FontSize="11" VerticalAlignment="Center"/>
                                        <Button Grid.Column="1" Content="Browse…" Command="{Binding BrowseBackgroundCommand}"
                                                Style="{StaticResource YtButtonSecondary}" Margin="4,0,0,0" Padding="8,2"/>
                                    </Grid>
                                    <TextBlock Text="{Binding BackgroundSizeMismatchText}"
                                               Foreground="#ef4444" FontSize="11" TextWrapping="Wrap"
                                               Margin="0,4,0,0"
                                               Visibility="{Binding BackgroundSizeMismatch, Converter={StaticResource BoolToVis}}"/>
                                </StackPanel>
                            </StackPanel>
                        </StackPanel>
                    </ScrollViewer>
                </Grid>
                <!-- Live mode: YouTube Live Chat (entire left panel replaced) -->
                <Grid Grid.Row="0" Visibility="{Binding IsEditMode, Converter={StaticResource InverseBoolToVis}}">
                    <Grid.RowDefinitions>
                        <RowDefinition Height="Auto"/>
                        <RowDefinition Height="*"/>
                    </Grid.RowDefinitions>
                    <TextBlock Grid.Row="0" Text="LIVE CHAT" Style="{StaticResource SectionHeader}"/>
                    <!-- Inactive overlay (shown when NOT live) -->
                    <StackPanel Grid.Row="1" VerticalAlignment="Center" HorizontalAlignment="Center"
                                Visibility="{Binding ShowChatInactiveMessage, Converter={StaticResource BoolToVis}}">
                        <TextBlock Text="Chat is inactive" Foreground="#a0a0b0" FontSize="13"
                                   HorizontalAlignment="Center" Margin="0,0,0,4"/>
                        <TextBlock Text="Chat becomes active once LlamaCasty is connected and streaming on YouTube."
                                   Foreground="#666" FontSize="11" TextWrapping="Wrap"
                                   HorizontalAlignment="Center" TextAlignment="Center" MaxWidth="240"/>
                    </StackPanel>
                    <!-- Message feed (shown when live) -->
                    <ListBox Grid.Row="1" Background="Transparent" BorderThickness="0"
                             ItemsSource="{Binding ChatMessages}"
                             ItemContainerStyle="{StaticResource YtListBoxItem}"
                             Visibility="{Binding ShowChatInactiveMessage, Converter={StaticResource InverseBoolToVis}}"
                             x:Name="ChatListBox">
                        <ListBox.ItemTemplate><DataTemplate>
                            <Border x:Name="MessageBorder" Padding="6,4" CornerRadius="4">
                                <Border.Style>
                                    <Style TargetType="Border">
                                        <Setter Property="Background" Value="Transparent"/>
                                        <Style.Triggers>
                                            <DataTrigger Binding="{Binding IsSuperChat}" Value="True">
                                                <Setter Property="Background" Value="#2a1a0a"/>
                                                <Setter Property="BorderBrush" Value="#eab308"/>
                                                <Setter Property="BorderThickness" Value="1,0,1,0"/>
                                            </DataTrigger>
                                        </Style.Triggers>
                                    </Style>
                                </Border.Style>
                                <StackPanel>
                                    <StackPanel Orientation="Horizontal" Margin="0,0,0,2">
                                        <TextBlock Text="&#x2B50;" FontSize="10" Margin="0,0,4,0"
                                                   VerticalAlignment="Center"
                                                   Visibility="{Binding IsMember, Converter={StaticResource BoolToVis}}"/>
                                        <TextBlock Text="{Binding AuthorName}" Foreground="#e94560"
                                                   FontWeight="Bold" FontSize="12" VerticalAlignment="Center"/>
                                        <TextBlock Text="{Binding SuperChatAmount, StringFormat=${0:F2}}"
                                                   Foreground="#eab308" FontWeight="Bold" FontSize="12"
                                                   Margin="8,0,0,0" VerticalAlignment="Center"
                                                   Visibility="{Binding IsSuperChat, Converter={StaticResource BoolToVis}}"/>
                                        <TextBlock Text="{Binding SuperChatCurrency}" Foreground="#eab308"
                                                   FontSize="11" Margin="2,0,0,0" VerticalAlignment="Center"
                                                   Visibility="{Binding IsSuperChat, Converter={StaticResource BoolToVis}}"/>
                                    </StackPanel>
                                    <TextBlock Text="{Binding Message}" Foreground="#e0e0e0"
                                               TextWrapping="Wrap" Margin="0,2,0,0"/>
                                </StackPanel>
                            </Border>
                        </DataTemplate></ListBox.ItemTemplate>
                    </ListBox>
                </Grid>
            </Grid>
    </Border>
 </UserControl>
@@ -0,0 +1,322 @@
 using System.Collections;
 using System.Windows;
 using System.Windows.Controls;
 using System.Windows.Input;
 using System.Windows.Media;
 using ytLive.Models;
 using ytLive.ViewModels;
 namespace ytLive.Controls;
 public partial class LeftPanel : UserControl
 {
    private Models.SceneElement? _snapshotElement;
    private string _snapshotBorderColor = string.Empty;
    private int _snapshotBorderWidth;
    private int _snapshotTimerMinutes = 15;
    private string? _snapshotWebUri;
    private Point _dragStartPoint;
    private int _dragIndex = -1;
    private bool _isDragging;
    private object? _lastHoveredItem;
    private bool _dragReordered;
    public LeftPanel()
    {
        InitializeComponent();
        Loaded += (_, _) =>
        {
            if (DataContext is MainViewModel vm)
                vm.ChatMessages.CollectionChanged += OnChatMessagesChanged;
        };
        Unloaded += (_, _) =>
        {
            if (DataContext is MainViewModel vm)
                vm.ChatMessages.CollectionChanged -= OnChatMessagesChanged;
        };
    }
    // Called by the window's UpdateSelectionOverlay (edit mode only).
    public void OnSelectionChanged(MainViewModel vm)
    {
        if (vm.SelectedElement is { } s && PreviewPane.IsDraggableElement(s))
            OpacityValueText.Text = $"{Math.Round(s.Opacity * 100)}%";
        TakeSnapshot(vm);
    }
    // Deselection guard: true when the click is inside the source list or the
    // element property scroller (window's Window_PreviewMouseLeftButtonDown).
    public bool IsClickInside(DependencyObject original)
        => IsDescendantOf(original, SourceList) || IsDescendantOf(original, ElementsScrollViewer);
    private static bool IsDescendantOf(DependencyObject? child, DependencyObject ancestor)
    {
        while (child != null && !ReferenceEquals(child, ancestor))
        {
            child = child is Visual or System.Windows.Media.Media3D.Visual3D
                ? VisualTreeHelper.GetParent(child)
                : LogicalTreeHelper.GetParent(child);
        }
        return child != null;
    }
    private void SourceNameBox_IsVisibleChanged(object sender, DependencyPropertyChangedEventArgs e)
    {
        if (sender is TextBox { IsVisible: true } box)
        {
            box.Focus();
            box.SelectAll();
        }
    }
    private void AddSourceButton_Click(object sender, RoutedEventArgs e)
    {
        if (sender is Button { ContextMenu: { } menu } button)
        {
            menu.PlacementTarget = button;
            menu.Placement = System.Windows.Controls.Primitives.PlacementMode.Bottom;
            menu.IsOpen = true;
        }
    }
    private void OnChatMessagesChanged(object? sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e)
    {
        if (e.Action == System.Collections.Specialized.NotifyCollectionChangedAction.Add)
        {
            ChatListBox.ScrollIntoView(ChatListBox.Items[^1]);
        }
    }
    private void MirrorButton_Click(object sender, RoutedEventArgs e)
    {
        if ((DataContext as MainViewModel)?.SelectedElement is WebcamSceneConfig webcam)
            webcam.IsMirrored = !webcam.IsMirrored;
    }
    private void ShapeButton_Click(object sender, RoutedEventArgs e)
    {
        if ((DataContext as MainViewModel)?.SelectedElement is WebcamSceneConfig webcam)
            webcam.ToggleClipShape();
    }
    private void SourceMenu_Remove(object sender, RoutedEventArgs e)
    {
        if (sender is MenuItem { DataContext: SceneElement element } && DataContext is MainViewModel vm)
            vm.RemoveSourceCommand.Execute(element);
    }
    private void BackgroundMenu_ChangeCapture(object sender, RoutedEventArgs e)
    {
        _ = (DataContext as MainViewModel)?.ChangeBackgroundCaptureAsync();
    }
    private void BackgroundMenu_RefreshCapture(object sender, RoutedEventArgs e)
    {
        (DataContext as MainViewModel)?.RefreshBackgroundAutoCapture();
    }
    private void BackgroundMenu_RefreshWindowList(object sender, RoutedEventArgs e)
    {
        (DataContext as MainViewModel)?.RefreshWindowsCommand.Execute(null);
    }
    private void OpacitySlider_ValueChanged(object sender, RoutedPropertyChangedEventArgs<double> e)
        => OpacityValueText.Text = $"{Math.Round(e.NewValue * 100)}%";
    private void SourceNameBox_KeyDown(object sender, KeyEventArgs e)
    {
        if (e.Key is Key.Enter or Key.Escape)
        {
            CommitSourceEdit(sender);
            e.Handled = true;
        }
    }
    private void SourceNameBox_LostFocus(object sender, RoutedEventArgs e)
    {
        CommitSourceEdit(sender);
    }
    private static void CommitSourceEdit(object sender)
    {
        if (sender is FrameworkElement { DataContext: SceneElement element })
            element.IsEditing = false;
    }
    // ─── List drag-to-reorder (scenes list + sources list) ───
    private void List_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
    {
        var listBox = (ListBox)sender;
        var item = FindItemContainerAt(listBox, e.GetPosition(listBox));
        if (item == null)
        {
            if (ReferenceEquals(listBox, SourceList))
                (DataContext as MainViewModel)!.SelectedElement = null;
            _dragIndex = -1;
            return;
        }
        if (listBox.ItemsSource is not IList items || items.Count == 0)
        {
            _dragIndex = -1;
            return;
        }
        _dragIndex = listBox.Items.IndexOf(item.DataContext);
        _dragStartPoint = e.GetPosition(listBox);
        _isDragging = false;
        _lastHoveredItem = null;
        _dragReordered = false;
    }
    private void List_PreviewMouseMove(object sender, MouseEventArgs e)
    {
        if (_dragIndex < 0) return;
        var listBox = (ListBox)sender;
        if (e.LeftButton != MouseButtonState.Pressed || listBox.ItemsSource is not IList items)
        {
            EndListDrag(listBox);
            return;
        }
        var position = e.GetPosition(listBox);
        if (!_isDragging)
        {
            if (Math.Abs(position.X - _dragStartPoint.X) < SystemParameters.MinimumHorizontalDragDistance &&
                Math.Abs(position.Y - _dragStartPoint.Y) < SystemParameters.MinimumVerticalDragDistance)
                return;
            _isDragging = true;
            listBox.CaptureMouse();
        }
        var item = FindItemContainerAt(listBox, position);
        if (item == null) return;
        var targetItem = item.DataContext;
        if (ReferenceEquals(targetItem, items[_dragIndex]) || ReferenceEquals(targetItem, _lastHoveredItem))
            return;
        var targetIndex = listBox.Items.IndexOf(targetItem);
        if (targetIndex < 0) return;
        var dragged = items[_dragIndex];
        items.RemoveAt(_dragIndex);
        items.Insert(targetIndex, dragged);
        _dragIndex = targetIndex;
        _lastHoveredItem = targetItem;
        _dragReordered = true;
    }
    private void List_PreviewMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
    {
        EndListDrag((ListBox)sender);
    }
    private void EndListDrag(ListBox listBox)
    {
        if (_isDragging)
            listBox.ReleaseMouseCapture();
        var reordered = _dragReordered;
        _dragIndex = -1;
        _isDragging = false;
        _lastHoveredItem = null;
        _dragReordered = false;
        if (reordered && DataContext is MainViewModel vm)
            vm.OnSceneElementsReordered();
    }
    private static ListBoxItem? FindItemContainerAt(ListBox listBox, Point position)
    {
        var hit = listBox.InputHitTest(position) as DependencyObject;
        while (hit != null && hit != listBox)
        {
            if (hit is ListBoxItem item) return item;
            hit = VisualTreeHelper.GetParent(hit);
        }
        return null;
    }
    private void TakeSnapshot(MainViewModel vm)
    {
        if (vm.SelectedElement is Models.Source src)
        {
            _snapshotElement = src;
            _snapshotBorderColor = src.BorderColor;
            _snapshotBorderWidth = src.BorderWidth;
            _snapshotTimerMinutes = src.TimerMinutes;
            _snapshotWebUri = src.WebUri;
        }
    }
    private void WebcamBorderColorPicker_Click(object sender, RoutedEventArgs e)
    {
        if ((DataContext as MainViewModel)?.SelectedElement is not SceneElement src) return;
        if (sender is FrameworkElement fe && fe.ContextMenu == null)
        {
            var menu = new System.Windows.Controls.ContextMenu();
            string[] colors = ["#FFFFFF", "#000000", "#FF0000", "#00FF00", "#0000FF",
                               "#FFFF00", "#FF00FF", "#00FFFF", "#FF8800", "#8800FF",
                               "#e94560", "#22c55e", "#3b82f6", "#f59e0b"];
            foreach (var c in colors)
            {
                var item = new System.Windows.Controls.MenuItem { Header = c, ToolTip = c };
                var brush = new System.Windows.Media.SolidColorBrush(
                    (System.Windows.Media.Color)System.Windows.Media.ColorConverter.ConvertFromString(c));
                item.Icon = new System.Windows.Controls.Border
                {
                    Width = 16, Height = 16,
                    Background = brush,
                    CornerRadius = new System.Windows.CornerRadius(2)
                };
                var color = c;
                item.Click += (_, _) => src.BorderColor = color;
                menu.Items.Add(item);
            }
            fe.ContextMenu = menu;
        }
        if (sender is FrameworkElement fe2)
            fe2.ContextMenu.IsOpen = true;
    }
    private void WebcamBorderRevert_Click(object sender, RoutedEventArgs e)
    {
        if (_snapshotElement is Models.Source src)
        {
            src.BorderColor = _snapshotBorderColor;
            src.BorderWidth = _snapshotBorderWidth;
        }
    }
    private void WebcamBorderAccept_Click(object sender, RoutedEventArgs e)
    {
        if (_snapshotElement is Models.Source src)
        {
            _snapshotBorderColor = src.BorderColor;
            _snapshotBorderWidth = src.BorderWidth;
        }
    }
    private void CountdownRevert_Click(object sender, RoutedEventArgs e)
    {
        if (_snapshotElement is Models.Source src)
            src.TimerMinutes = _snapshotTimerMinutes;
    }
    private void CountdownAccept_Click(object sender, RoutedEventArgs e)
    {
        if (_snapshotElement is Models.Source src)
            _snapshotTimerMinutes = src.TimerMinutes;
    }
    private void WebRevert_Click(object sender, RoutedEventArgs e)
    {
        if (_snapshotElement is Models.Source src)
            src.WebUri = string.Empty;
        _snapshotWebUri = string.Empty;
    }
    private void WebAccept_Click(object sender, RoutedEventArgs e)
    {
        if (_snapshotElement is Models.Source src)
            _snapshotWebUri = src.WebUri;
    }
 }
@@ -0,0 +1,179 @@
 <UserControl x:Class="ytLive.Controls.OverlayHost"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:Helpers="clr-namespace:ytLive.Helpers"
             xmlns:Models="clr-namespace:ytLive.Models">
        <Grid Grid.RowSpan="3"
              Visibility="{Binding IsAnyOverlayOpen, Converter={StaticResource BoolToVis}}">
            <Button Background="#99000000" BorderThickness="0" Cursor="Hand"
                    Command="{Binding CloseOverlayCommand}">
                <Button.Template>
                    <ControlTemplate TargetType="Button">
                        <Border Background="{TemplateBinding Background}"/>
                    </ControlTemplate>
                </Button.Template>
            </Button>
            <Border Background="#0A0C1A" CornerRadius="8" Width="650" MaxHeight="700"
                    VerticalAlignment="Center" HorizontalAlignment="Center"
                    Padding="28" BorderBrush="#333" BorderThickness="1">
                <Grid>
                    <Grid.RowDefinitions>
                        <RowDefinition Height="Auto"/>
                        <RowDefinition Height="Auto"/>
                    </Grid.RowDefinitions>
                    <!-- Header -->
                    <Grid Grid.Row="0">
                        <TextBlock Text="{Binding OverlayTitle}" FontSize="18" FontWeight="Bold"
                                   Foreground="#e0e0e0" VerticalAlignment="Center"/>
                        <Button HorizontalAlignment="Right" ToolTip="Close" Style="{StaticResource IconButton}"
                                Command="{Binding CloseOverlayCommand}">
                            <Path Data="M19,6.41L17.59,5 12,10.59 6.41,5 5,6.41 10.59,12 5,17.59 6.41,19 12,13.41 17.59,19 19,17.59 13.41,12z"
                                  Fill="#d0d0d0" Width="14" Height="14" Stretch="Uniform"/>
                        </Button>
                    </Grid>
                    <!-- App Settings: broadcast fields live in the preview's
                         Text pull-out now — this panel keeps app-level prefs only.
                         (Currently empty; the overlay shell stays for future use.) -->
                    <StackPanel Grid.Row="1" Margin="0,16,0,0"
                                Visibility="{Binding IsSettingsOpen, Converter={StaticResource BoolToVis}}">
                        <TextBlock Text="Default Location for Recordings" Style="{StaticResource YtLabel}" Margin="0,0,0,4"/>
                        <TextBox Style="{StaticResource YtTextBox}" 
                                 Text="{Binding RecordFolderDisplay, Mode=OneWay}"
                                 IsReadOnly="True" Margin="0,0,0,12" Foreground="#a0a0b0"/>
                        <StackPanel Orientation="Horizontal" Margin="0,0,0,16">
                            <Button Content="Browse…" Command="{Binding ChooseRecordFolderCommand}"
                                    Style="{StaticResource YtButtonSecondary}" Margin="0,0,8,0"/>
                            <Button Content="Use Downloads" Command="{Binding ResetRecordFolderCommand}"
                                    Style="{StaticResource YtButtonSecondary}"/>
                        </StackPanel>
                        <TextBlock Text="Zoom View Shape" Style="{StaticResource YtLabel}" Margin="0,0,0,4"/>
                        <ComboBox Style="{StaticResource YtComboBox}" SelectedValue="{Binding ZoomShape}" SelectedValuePath="Tag">
                            <ComboBoxItem Content="Circle" Tag="{x:Static Models:ZoomShape.Circle}"/>
                            <ComboBoxItem Content="Phone (Vertical Rectangle)" Tag="{x:Static Models:ZoomShape.VerticalRectangle}"/>
                            <ComboBoxItem Content="Tablet (Horizontal Rectangle)" Tag="{x:Static Models:ZoomShape.HorizontalRectangle}"/>
                        </ComboBox>
                    </StackPanel>
                    <!-- Report Bug -->
                    <StackPanel Grid.Row="1" Margin="0,16,0,0"
                                Visibility="{Binding IsBugOpen, Converter={StaticResource BoolToVis}}">
                        <TextBlock Text="What went wrong?" Style="{StaticResource YtLabel}" Margin="0,0,0,4"/>
                        <TextBox Style="{StaticResource YtTextBox}" Height="110" AcceptsReturn="True" TextWrapping="Wrap"
                                 Margin="0,0,0,12"
                                 Text="{Binding BugReportText, UpdateSourceTrigger=PropertyChanged}"
                                 VerticalScrollBarVisibility="Auto"/>
                        <TextBlock Text="Email (optional)" Style="{StaticResource YtLabel}" Margin="0,0,0,4"/>
                        <TextBox Style="{StaticResource YtTextBox}" Margin="0,0,0,12"
                                 Text="{Binding BugReportEmail, UpdateSourceTrigger=PropertyChanged}"/>
                        <TextBlock Text="Opens a pre-filled email to the LlamaCasty team." Style="{StaticResource YtLabel}"/>
                        <Button Content="Send Report" Command="{Binding SubmitBugCommand}"
                                Style="{StaticResource YtButton}" HorizontalAlignment="Right" Margin="0,16,0,0"/>
                    </StackPanel>
                    <!-- Feature Request -->
                    <StackPanel Grid.Row="1" Margin="0,16,0,0"
                                Visibility="{Binding IsFeatureOpen, Converter={StaticResource BoolToVis}}">
                        <TextBlock Text="What would you like to see?" Style="{StaticResource YtLabel}" Margin="0,0,0,4"/>
                        <TextBox Style="{StaticResource YtTextBox}" Height="110" AcceptsReturn="True" TextWrapping="Wrap"
                                 Margin="0,0,0,12"
                                 Text="{Binding FeatureRequestText, UpdateSourceTrigger=PropertyChanged}"
                                 VerticalScrollBarVisibility="Auto"/>
                        <TextBlock Text="Email (optional)" Style="{StaticResource YtLabel}" Margin="0,0,0,4"/>
                        <TextBox Style="{StaticResource YtTextBox}" Margin="0,0,0,12"
                                 Text="{Binding FeatureRequestEmail, UpdateSourceTrigger=PropertyChanged}"/>
                        <TextBlock Text="Opens a pre-filled email to the LlamaCasty team." Style="{StaticResource YtLabel}"/>
                        <Button Content="Send Request" Command="{Binding SubmitFeatureCommand}"
                                Style="{StaticResource YtButton}" HorizontalAlignment="Right" Margin="0,16,0,0"/>
                    </StackPanel>
                    <!-- About -->
                    <Grid Grid.Row="1" Margin="0,16,0,0"
                          Background="#171928"
                          Visibility="{Binding IsAboutOpen, Converter={StaticResource BoolToVis}}">
                        <!-- Hub view -->
                        <StackPanel Visibility="{Binding IsHubVisible, Converter={StaticResource BoolToVis}}">
                            <Image Source="/ytLive;component/Assets/llamacasty-logo.jpg" Height="125" Stretch="Uniform"
                                   HorizontalAlignment="Center" Margin="0,0,0,12"/>
                            <TextBlock Text="{Binding AppVersionLabel}" Foreground="#a0a0b0" FontSize="12"
                                       HorizontalAlignment="Center" Margin="0,4,0,0"/>
                            <TextBlock Text="Live streaming for YouTube — simple enough that even the most right-brained person can intuit it."
                                       Foreground="#a0a0b0" FontSize="13" TextWrapping="Wrap" MaxWidth="380"
                                       TextAlignment="Center" Margin="0,16,0,0"/>
                            <TextBlock Text="Free forever — live streams carry a brief &quot;made with LlamaCasty!&quot; flash. A subscription removes it and adds alerts."
                                       Foreground="#888" FontSize="12" TextWrapping="Wrap" MaxWidth="380"
                                       TextAlignment="Center" Margin="0,12,0,0"/>
                            <TextBlock Text="Made by gramps · llama chile shop" Foreground="#a0a0b0" FontSize="12"
                                       HorizontalAlignment="Center" Margin="0,16,0,8"/>
                            <!-- Creator hub links -->
                            <StackPanel Orientation="Horizontal" HorizontalAlignment="Center" Margin="0,0,0,8">
                                <Button Content="llama chile shop on YouTube" Command="{Binding OpenChannelCommand}"
                                        Style="{StaticResource YtButtonSecondary}" Margin="0,0,8,0"/>
                                <Button Content="Mastodon" Command="{Binding OpenMastodonCommand}"
                                        Style="{StaticResource YtButtonSecondary}"/>
                            </StackPanel>
                            <StackPanel Orientation="Horizontal" HorizontalAlignment="Center">
                                <Button Content="Buy me a coffee" Command="{Binding OpenCoffeeCommand}"
                                        Style="{StaticResource YtButtonSecondary}" Margin="0,0,8,0"/>
                                <Button Content="Unlock Premium" Command="{Binding OpenPremiumCommand}"
                                        Style="{StaticResource YtButtonSecondary}"
                                        IsEnabled="{Binding IsPremiumAvailable}"
                                        ToolTip="Open the LlamaCasty subscription page"/>
                                <Button Content="Enter License Key" Command="{Binding OpenLicenseEntryCommand}"
                                        Style="{StaticResource YtButtonSecondary}"
                                        ToolTip="Activate a license key to remove the watermark"/>
                            </StackPanel>
                            <Button Content="Licenses &amp; legal" Command="{Binding OpenLicensesCommand}"
                                    Style="{StaticResource YtButtonSecondary}" HorizontalAlignment="Center"
                                    Margin="0,16,0,0"/>
                        </StackPanel>
                        <!-- Licensing/legal panel -->
                        <StackPanel Visibility="{Binding IsLicensesOpen, Converter={StaticResource BoolToVis}}">
                            <TextBlock Text="Third-party notices &amp; license texts" FontSize="15" FontWeight="Bold"
                                       Foreground="#e0e0e0" Margin="0,0,0,8"/>
                            <Border Background="#10101e" CornerRadius="4" Padding="10" MaxHeight="360"
                                    BorderBrush="#333" BorderThickness="1">
                                <ScrollViewer VerticalScrollBarVisibility="Auto">
                                    <TextBlock Text="{Binding LicensesText}" Foreground="#b8b8c8" FontSize="11"
                                               FontFamily="Consolas" TextWrapping="Wrap"/>
                                </ScrollViewer>
                            </Border>
                            <Button Content="← Back to About" Style="{StaticResource YtButtonSecondary}"
                                    HorizontalAlignment="Left" Margin="0,12,0,0"
                                    Click="BackToAbout_Click"/>
                        </StackPanel>
                        <!-- License key entry panel -->
                        <StackPanel Visibility="{Binding IsLicenseEntryOpen, Converter={StaticResource BoolToVis}}">
                            <TextBlock Text="Activate LlamaCasty Premium" FontSize="15" FontWeight="Bold"
                                       Foreground="#e0e0e0" Margin="0,0,0,8"/>
                            <TextBlock Text="Enter your license key to remove the branding watermark."
                                       Foreground="#a0a0b0" FontSize="12" TextWrapping="Wrap" Margin="0,0,0,12"/>
                            <TextBlock Text="License Key" Style="{StaticResource YtLabel}" Margin="0,0,0,4"/>
                            <TextBox Style="{StaticResource YtTextBox}" Margin="0,0,0,12"
                                     Text="{Binding LicenseKey, UpdateSourceTrigger=PropertyChanged}"
                                     MaxLength="100"/>
                            <Button Content="Activate" Command="{Binding ActivateLicenseCommand}"
                                    Style="{StaticResource YtButton}" HorizontalAlignment="Right"
                                    Margin="0,0,0,8"/>
                            <TextBlock Text="{Binding LicenseMessage}" Foreground="#a0a0b0" FontSize="12"
                                       TextWrapping="Wrap" Margin="0,0,0,8"/>
                            <Button Content="← Back to About" Style="{StaticResource YtButtonSecondary}"
                                    HorizontalAlignment="Left" Margin="0,8,0,0"
                                    Click="BackToAbout_Click"/>
                        </StackPanel>
                    </Grid>
                </Grid>
            </Border>
        </Grid>
 </UserControl>
@@ -0,0 +1,22 @@
 using System.Windows;
 using System.Windows.Controls;
 using ytLive.ViewModels;
 namespace ytLive.Controls;
 public partial class OverlayHost : UserControl
 {
    public OverlayHost()
    {
        InitializeComponent();
    }
    private void BackToAbout_Click(object sender, RoutedEventArgs e)
    {
        if (DataContext is MainViewModel vm)
        {
            vm.IsLicensesOpen = false;
            vm.IsLicenseEntryOpen = false;
        }
    }
 }
@@ -0,0 +1,586 @@
 using System;
 using System.Windows;
 using System.Windows.Controls;
 using System.Windows.Input;
 using System.Windows.Media;
 using System.Windows.Media.Effects;
 using System.Windows.Media.Animation;
 using System.Windows.Shapes;
 using System.Windows.Threading;
 using ytLive.Helpers;
 using ytLive.Models;
 using ytLive.ViewModels;
 namespace ytLive.Controls;
 public partial class PreviewPane : UserControl
 {
    private bool _isDraggingOverlay;
    private bool _isResizing;
    private bool _isZoomDragging;
    private Point _grabOffset;
    private double _resizeAspect;
    private readonly System.Collections.Generic.Dictionary<string, Storyboard> _activeBorderAnimations =
        new();
    private DispatcherTimer? _socialGlowTimer;
    private double _socialGlowAngle;
    public PreviewPane()
    {
        InitializeComponent();
        DataContextChanged += PreviewPane_DataContextChanged;
    }
    private void PreviewPane_DataContextChanged(object sender, DependencyPropertyChangedEventArgs e)
    {
        if (e.OldValue is MainViewModel oldVm)
            oldVm.PropertyChanged -= ViewModel_PropertyChanged;
        if (e.NewValue is MainViewModel newVm)
        {
            newVm.PropertyChanged += ViewModel_PropertyChanged;
            UpdateZoomBox();
        }
    }
    private void ViewModel_PropertyChanged(object? sender, System.ComponentModel.PropertyChangedEventArgs e)
    {
        if (e.PropertyName == nameof(MainViewModel.IsZoomActive) || e.PropertyName == nameof(MainViewModel.ZoomState) || e.PropertyName == nameof(MainViewModel.ZoomShape))
        {
            UpdateZoomBox();
        }
    }
    // Static images and the webcam share the move/resize/selection behavior.
    public static bool IsDraggableElement(SceneElement element)
        => element.IsDraggable;
    public void UpdateSelectionOverlay(bool selected)
    {
        SelectionOverlay.Visibility = selected ? Visibility.Visible : Visibility.Collapsed;
    }
    // ─── Clicking inside the preview / pull-out drawer (used by the window's
    //     Window_PreviewMouseLeftButtonDown deselection logic) ───
    public bool IsClickInsidePreview(DependencyObject original)
        => IsDescendantOf(original, PreviewGrid);
    public bool IsClickInsideDrawer(DependencyObject original)
        => IsDescendantOf(original, TextPullOutHost);
    private static bool IsDescendantOf(DependencyObject? child, DependencyObject ancestor)
    {
        while (child != null && !ReferenceEquals(child, ancestor))
        {
            child = child is Visual or System.Windows.Media.Media3D.Visual3D
                ? VisualTreeHelper.GetParent(child)
                : LogicalTreeHelper.GetParent(child);
        }
        return child != null;
    }
    // ─── Audio meters + TRAX + socials (ROW 2 of the preview pane) ───
    private void VolumeSlider_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
    {
        if (sender is Slider slider)
            SetSliderValueFromClick(slider, e);
        if (sender is FrameworkElement { DataContext: MainViewModel vm })
            vm.SetVolumeAdjusting(true);
    }
    private void VolumeSlider_PreviewMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
    {
        if (sender is FrameworkElement { DataContext: MainViewModel vm })
            vm.SetVolumeAdjusting(false);
    }
    private void VolumeSlider_LostMouseCapture(object sender, MouseEventArgs e)
    {
        if (sender is FrameworkElement { DataContext: MainViewModel vm })
            vm.SetVolumeAdjusting(false);
    }
    private void GameVolumeSlider_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
    {
        if (sender is Slider slider)
            SetSliderValueFromClick(slider, e);
        if (sender is FrameworkElement { DataContext: MainViewModel vm })
            vm.SetGameVolumeAdjusting(true);
    }
    private void GameVolumeSlider_PreviewMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
    {
        if (sender is FrameworkElement { DataContext: MainViewModel vm })
            vm.SetGameVolumeAdjusting(false);
    }
    private void GameVolumeSlider_LostMouseCapture(object sender, MouseEventArgs e)
    {
        if (sender is FrameworkElement { DataContext: MainViewModel vm })
            vm.SetGameVolumeAdjusting(false);
    }
    private static void SetSliderValueFromClick(Slider slider, MouseButtonEventArgs e)
    {
        if (FindParent<System.Windows.Controls.Primitives.Thumb>(e.OriginalSource as Visual) != null)
            return;
        var track = slider.Template.FindName("PART_Track", slider) as System.Windows.Controls.Primitives.Track;
        if (track == null) return;
        var pos = e.GetPosition(track);
        var fraction = Math.Clamp(pos.X / track.RenderSize.Width, 0, 1);
        slider.Value = slider.Minimum + fraction * (slider.Maximum - slider.Minimum);
        e.Handled = true;
    }
    private static T? FindParent<T>(Visual? visual) where T : Visual
    {
        while (visual != null)
        {
            if (visual is T match) return match;
            visual = VisualTreeHelper.GetParent(visual) as Visual;
        }
        return null;
    }
    private void MicSpeaker_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
    {
        if (sender is FrameworkElement { DataContext: MainViewModel vm })
        {
            vm.ToggleMicMuteCommand.Execute(null);
        }
    }
    private void GameSpeaker_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
    {
        if (sender is FrameworkElement { DataContext: MainViewModel vm })
        {
            vm.ToggleGameMuteCommand.Execute(null);
        }
    }
    // TRAX (TASK 9): left-click toggles play/pause (picks a track when none is
    // loaded); right-click always opens the picker. The picker is the OS file
    // dialog — the "never the OS viewer" rule covers the preview, not pickers.
    private void TraxButton_Click(object sender, RoutedEventArgs e)
    {
        if (DataContext is ViewModels.MainViewModel vm)
            vm.TraxLeftClick();
    }
    private void TraxButton_PreviewMouseRightButtonUp(object sender, MouseButtonEventArgs e)
    {
        if (DataContext is ViewModels.MainViewModel vm)
            vm.TraxRightClick();
        e.Handled = true; // the button's right-click context menu must not fire
    }
    // ─── Webcam / background context menus (right-click on overlay elements) ───
    private void WebcamMenu_ChangeWebcam(object sender, RoutedEventArgs e)
        => (DataContext as MainViewModel)?.ChangeWebcamCommand.Execute(null);
    private void WebcamMenu_SetBorderAnimation(object sender, RoutedEventArgs e)
    {
        if (sender is not MenuItem { DataContext: SceneElement element, Tag: string tag }
            || !Enum.TryParse<BorderAnimation>(tag, out var animation))
            return;
        element.BorderAnimation = animation;
        StopBorderAnimation(element.Id);
        if (animation == BorderAnimation.None) return;
        var shape = FindBorderShape(sender as DependencyObject);
        if (shape == null) return;
        var sb = CreateBorderAnimation(animation, shape);
        if (sb == null) return;
        sb.Freeze();
        _activeBorderAnimations[element.Id] = sb;
        shape.BeginAnimation(Shape.OpacityProperty, null);
        Storyboard.SetTarget(sb, shape);
        sb.Begin();
    }
    private void StopBorderAnimation(string elementId)
    {
        if (_activeBorderAnimations.TryGetValue(elementId, out var old))
        {
            old.Stop();
            _activeBorderAnimations.Remove(elementId);
        }
    }
    private static Shape? FindBorderShape(DependencyObject? start)
    {
        var current = start;
        while (current != null)
        {
            if (current is ContextMenu cm && cm.PlacementTarget is FrameworkElement target)
            {
                for (var i = 0; i < VisualTreeHelper.GetChildrenCount(target); i++)
                {
                    var child = VisualTreeHelper.GetChild(target, i);
                    if (child is Shape s && (s is Rectangle or Ellipse) && !s.IsHitTestVisible)
                        return s;
                }
                return null;
            }
            current = VisualTreeHelper.GetParent(current);
        }
        return null;
    }
    private static Storyboard? CreateBorderAnimation(BorderAnimation animation, Shape shape)
    {
        var sb = new Storyboard();
        switch (animation)
        {
            case BorderAnimation.Pulse:
                AddDoubleAnimation(sb, Shape.OpacityProperty, 1.0, 0.3, TimeSpan.FromSeconds(0.8), true);
                break;
            case BorderAnimation.Glow:
                AddDoubleAnimation(sb, Shape.OpacityProperty, 1.0, 0.5, TimeSpan.FromSeconds(1.2), true);
                break;
            case BorderAnimation.Shimmer:
                AddDoubleAnimation(sb, Shape.OpacityProperty, 1.0, 0.15, TimeSpan.FromSeconds(0.5), true);
                break;
            case BorderAnimation.Electricity:
                AddDoubleAnimation(sb, Shape.OpacityProperty, 1.0, 0.2, TimeSpan.FromSeconds(0.1), true);
                break;
            case BorderAnimation.Sparkles:
                AddDoubleAnimation(sb, Shape.OpacityProperty, 1.0, 0.4, TimeSpan.FromSeconds(0.3), true);
                break;
            case BorderAnimation.MarchingAnts:
                shape.StrokeDashArray = new DoubleCollection { 4, 2 };
                AddDoubleAnimation(sb, Shape.StrokeDashOffsetProperty, 0, -20, TimeSpan.FromSeconds(0.8), false);
                break;
            case BorderAnimation.Chase:
                shape.StrokeDashArray = new DoubleCollection { 8, 4 };
                AddDoubleAnimation(sb, Shape.StrokeDashOffsetProperty, 0, -30, TimeSpan.FromSeconds(1.5), false);
                break;
            case BorderAnimation.Rainbow:
                if (shape.Stroke is SolidColorBrush brush)
                {
                    var frozen = brush.IsFrozen;
                    if (frozen) brush = brush.Clone();
                    shape.Stroke = brush;
                    var colorAnim = new ColorAnimationUsingKeyFrames
                    {
                        Duration = new Duration(TimeSpan.FromSeconds(3)),
                        RepeatBehavior = RepeatBehavior.Forever
                    };
                    colorAnim.KeyFrames.Add(new LinearColorKeyFrame(Colors.Red, KeyTime.FromTimeSpan(TimeSpan.Zero)));
                    colorAnim.KeyFrames.Add(new LinearColorKeyFrame(Colors.Yellow, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(0.5))));
                    colorAnim.KeyFrames.Add(new LinearColorKeyFrame(Colors.Green, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(1))));
                    colorAnim.KeyFrames.Add(new LinearColorKeyFrame(Colors.DodgerBlue, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(1.5))));
                    colorAnim.KeyFrames.Add(new LinearColorKeyFrame(Colors.MediumPurple, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(2))));
                    colorAnim.KeyFrames.Add(new LinearColorKeyFrame(Colors.Red, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(2.5))));
                    Storyboard.SetTargetProperty(colorAnim, new PropertyPath("(Shape.Stroke).(SolidColorBrush.Color)"));
                    sb.Children.Add(colorAnim);
                }
                break;
            default:
                return null;
        }
        return sb.Children.Count > 0 ? sb : null;
    }
    private static void AddDoubleAnimation(Storyboard sb, DependencyProperty prop,
        double from, double to, Duration duration, bool autoReverse)
    {
        var anim = new DoubleAnimation(from, to, duration)
        {
            AutoReverse = autoReverse,
            RepeatBehavior = RepeatBehavior.Forever
        };
        Storyboard.SetTargetProperty(anim, new PropertyPath(prop));
        sb.Children.Add(anim);
    }
    private void WebcamMenu_SetBorderColor(object sender, RoutedEventArgs e)
    {
        if (sender is MenuItem { DataContext: SceneElement element, Tag: string color })
            element.BorderColor = color;
    }
    private void WebcamMenu_HideInScene(object sender, RoutedEventArgs e)
    {
        if (sender is MenuItem { DataContext: SceneElement element })
            element.IsVisible = false;
    }
    private void WebcamMenu_Remove(object sender, RoutedEventArgs e)
    {
        if (sender is MenuItem { DataContext: SceneElement element })
            (DataContext as MainViewModel)?.RemoveSourceCommand.Execute(element);
    }
    // ─── Social bar: click toggles top ⇄ bottom. KISS — the drag variant was
    // unusable for shaky hands (jitter around the direction deadzone), so the bar
    // rides on {Binding SocialBarTop} alone and a click flips it. ───
    private void SocialBar_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
    {
        (DataContext as MainViewModel)?.ToggleSocialBarPosition();
        e.Handled = true;
    }
    private void SocialsButton_MouseEnter(object sender, MouseEventArgs e)
    {
        if (SocialBarElement == null) return;
        // Kick the social bar to full brightness so it's immediately visible
        var effect = SocialBarElement.Effect as DropShadowEffect;
        if (effect != null)
        {
            effect.BlurRadius = 40;
            effect.Opacity = 1.0;
        }
        // Pulse the glow so it catches the eye
        _socialGlowAngle = 0;
        _socialGlowTimer?.Stop();
        _socialGlowTimer = new DispatcherTimer { Interval = TimeSpan.FromMilliseconds(30) };
        _socialGlowTimer.Tick += SocialGlowTick;
        _socialGlowTimer.Start();
    }
    private void SocialsButton_MouseLeave(object sender, MouseEventArgs e)
    {
        _socialGlowTimer?.Stop();
        _socialGlowTimer = null;
        if (SocialBarElement?.Effect is DropShadowEffect effect)
        {
            effect.BlurRadius = 18;
            effect.Opacity = 0.9;
        }
    }
    private void SocialGlowTick(object? sender, EventArgs e)
    {
        if (SocialBarElement?.Effect is not DropShadowEffect effect) return;
        _socialGlowAngle += 0.18;
        if (_socialGlowAngle > Math.PI * 2) _socialGlowAngle -= Math.PI * 2;
        // Smooth sine pulse: BlurRadius 24→48, Opacity 0.7→1.0
        double t = (Math.Sin(_socialGlowAngle) + 1.0) / 2.0; // 0..1
        effect.BlurRadius = 24 + t * 24;
        effect.Opacity = 0.7 + t * 0.3;
    }
    // ─── Preview: element selection / move / resize / hit-testing ───
    private void Preview_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
    {
        var vm = DataContext as MainViewModel;
        if (vm is null || !vm.IsEditMode) return;
        var grid = (Grid)sender;
        var toCanvas = CanvasGrid.TransformToVisual(grid).Inverse;
        var p = toCanvas.Transform(e.GetPosition(grid));
        var selected = vm.SelectedElement;
        if (selected is { } sel && IsDraggableElement(sel) && HitHandle(e.GetPosition(grid), sel))
        {
            _isResizing = true;
            _resizeAspect = sel.ClipShape == ClipShape.Round ? 1 : sel.Width / Math.Max(1, sel.Height);
            grid.CaptureMouse();
            e.Handled = true;
            return;
        }
        var hit = HitElement(vm, p);
        if (hit != null)
        {
            vm.SelectedElement = hit;
            _isDraggingOverlay = true;
            _grabOffset = new Point(p.X - hit.X, p.Y - hit.Y);
            grid.CaptureMouse();
            e.Handled = true;
            return;
        }
        vm.SelectedElement = null;
    }
    private void Preview_MouseMove(object sender, MouseEventArgs e)
    {
        var vm = DataContext as MainViewModel;
        if (vm is null) return;
        var grid = (Grid)sender;
        var toCanvas = CanvasGrid.TransformToVisual(grid).Inverse;
        var p = toCanvas.Transform(e.GetPosition(grid));
        if (e.LeftButton == MouseButtonState.Pressed && vm.IsZoomActive)
        {
            if (!_isZoomDragging)
            {
                vm.StartZoomMove(p.X, p.Y);
                _isZoomDragging = true;
                grid.CaptureMouse();
            }
            else
            {
                vm.UpdateZoomMove(p.X, p.Y);
            }
            return;
        }
        if (!vm.IsEditMode) return;
        if (!_isDraggingOverlay && !_isResizing) return;
        var selected = vm.SelectedElement;
        if (selected == null)
        {
            EndPreviewDrag(grid);
            return;
        }
        if (_isDraggingOverlay)
        {
            var minX = -(selected.Width - 20);
            var maxX = 1920 - 20;
            var minY = -(selected.Height - 20);
            var maxY = 1080 - 20;
            selected.X = Math.Clamp(p.X - _grabOffset.X, Math.Min(minX, maxX), Math.Max(minX, maxX));
            selected.Y = Math.Clamp(p.Y - _grabOffset.Y, Math.Min(minY, maxY), Math.Max(minY, maxY));
        }
        else if (_isResizing)
        {
            var isWebcam = selected is WebcamSceneConfig;
            var isRound = selected.ClipShape == ClipShape.Round;
            var proportional = isRound || Keyboard.Modifiers.HasFlag(ModifierKeys.Shift);
            var maxW = isWebcam ? MainViewModel.MaxWebcamWidthFor(vm.StagedScene?.Name) : 1920;
            var maxH = isWebcam ? MainViewModel.MaxWebcamHeightFor(vm.StagedScene?.Name) : 1080;
            var newW = Math.Clamp(p.X - selected.X, 32, maxW);
            var newH = proportional ? newW / _resizeAspect : Math.Clamp(p.Y - selected.Y, 32, maxH);
            if (proportional && newH > maxH)
            {
                newH = maxH;
                newW = newH * _resizeAspect;
            }
            selected.Width = newW;
            selected.Height = newH;
        }
    }
    private void Preview_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
    {
        if (_isZoomDragging && DataContext is MainViewModel vm)
        {
            vm.EndZoomMove();
            _isZoomDragging = false;
            ((Grid)sender).ReleaseMouseCapture();
            e.Handled = true;
            return;
        }
        EndPreviewDrag((Grid)sender);
    }
    private void Preview_MouseRightButtonDown(object sender, MouseButtonEventArgs e)
    {
        var vm = DataContext as MainViewModel;
        if (vm == null) return;
        var grid = (Grid)sender;
        var toCanvas = CanvasGrid.TransformToVisual(grid).Inverse;
        var p = toCanvas.Transform(e.GetPosition(grid));
        if ((vm.IsLive || vm.IsRecording) && !vm.IsEditMode)
        {
            if (vm.IsZoomActive)
            {
                vm.DismissZoom();
                e.Handled = true;
                return;
            }
            vm.ActivateZoom(p.X, p.Y);
            e.Handled = true;
            return;
        }
        vm.ToggleZoom();
        e.Handled = true;
    }    private void Preview_MouseRightButtonUp(object sender, MouseButtonEventArgs e)
    {
        if (_isZoomDragging)
        {
            var grid = (Grid)sender;
            grid.ReleaseMouseCapture();
            _isZoomDragging = false;
            if (DataContext is MainViewModel vm) vm.EndZoomMove();
            e.Handled = true;
            return;
        }
    }
    private void EndPreviewDrag(Grid grid)
    {
        if (_isDraggingOverlay || _isResizing || _isZoomDragging)
            grid.ReleaseMouseCapture();
        _isDraggingOverlay = false;
        _isResizing = false;
        _isZoomDragging = false;
        if (DataContext is MainViewModel vm) vm.EndZoomMove();
    }
    private bool HitHandle(Point mouseScreen, SceneElement element)
    {
        var corner = CanvasGrid.TransformToVisual(PreviewGrid).Transform(new Point(element.X + element.Width, element.Y + element.Height));
        return Math.Abs(mouseScreen.X - corner.X) <= 20 && Math.Abs(mouseScreen.Y - corner.Y) <= 20;
    }
    private SceneElement? HitElement(MainViewModel vm, Point p)
    {
        var scene = vm.StagedScene;
        if (scene == null) return null;
        for (var i = scene.Elements.Count - 1; i >= 0; i--)
        {
            var element = scene.Elements[i];
            if (!IsDraggableElement(element)) continue;
            if (element is Source { IsEnabled: false }) continue;
            if (element is WebcamSceneConfig { IsVisible: false }) continue;
            if (p.X >= element.X && p.X <= element.X + element.Width &&
                p.Y >= element.Y && p.Y <= element.Y + element.Height)
                return element;
        }
        return null;
    }
    private void UpdateZoomBox()
    {
        if (DataContext is not MainViewModel vm) return;
        if (vm.IsZoomActive && ZoomVisualBrush != null)
        {
            // The preview mirrors the output zoom layer: sample the WHOLE composed
            // preview (CanvasGrid = backdrop + every element layer — the same all-layer
            // source the output compositor magnifies) at the FIXED capture window (the
            // box/2 region centred on the click) → 2x via Stretch=Fill. Moving the box
            // only moves the ZoomBox element; the Viewbox stays glued to the capture.
            ZoomVisualBrush.Visual = CanvasGrid;
            ZoomVisualBrush.Viewbox = new Rect(
                vm.ZoomState.CaptureX,
                vm.ZoomState.CaptureY,
                vm.ZoomState.Width / 2,
                vm.ZoomState.Height / 2);
            ZoomVisualBrush.ViewboxUnits = BrushMappingMode.Absolute;
            if (vm.ZoomShape == Models.ZoomShape.Circle)
            {
                ZoomCircleOutline.Visibility = Visibility.Visible;
                ZoomRectOutline.Visibility = Visibility.Collapsed;
                ZoomBox.Clip = new EllipseGeometry(new Rect(0, 0, vm.ZoomState.Width, vm.ZoomState.Height));
            }
            else
            {
                ZoomCircleOutline.Visibility = Visibility.Collapsed;
                ZoomRectOutline.Visibility = Visibility.Visible;
                ZoomBox.Clip = null;
            }
        }
        else if (!vm.IsZoomActive && ZoomVisualBrush != null && ReferenceEquals(ZoomVisualBrush.Visual, CanvasGrid))
        {
            ZoomVisualBrush.Visual = null;
        }
    }
 }
@@ -0,0 +1,54 @@
 <UserControl x:Class="ytLive.Controls.SceneThumbnailStrip"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
    <Border Background="#0d1117" CornerRadius="4" Margin="0,0,0,4" Padding="4">
        <ItemsControl ItemsSource="{Binding Scenes}">
            <ItemsControl.ItemsPanel>
                <ItemsPanelTemplate>
                    <UniformGrid Rows="1" Columns="5"/>
                </ItemsPanelTemplate>
            </ItemsControl.ItemsPanel>
            <ItemsControl.ItemTemplate>
                <DataTemplate>
                    <Border CornerRadius="4" Margin="2" Padding="2"
                            BorderThickness="2"
                            BorderBrush="Transparent"
                            Cursor="Hand"
                            MouseLeftButtonDown="Thumbnail_MouseLeftButtonDown">
                        <Border.Style>
                            <Style TargetType="Border">
                                <Setter Property="BorderBrush" Value="#333344"/>
                                <Style.Triggers>
                                    <DataTrigger Binding="{Binding IsStaged}" Value="True">
                                        <Setter Property="BorderBrush" Value="#e94560"/>
                                    </DataTrigger>
                                    <DataTrigger Binding="{Binding IsLive}" Value="True">
                                        <Setter Property="BorderBrush" Value="#22c55e"/>
                                    </DataTrigger>
                                </Style.Triggers>
                            </Style>
                        </Border.Style>
                        <Grid>
                            <Grid.RowDefinitions>
                                <RowDefinition Height="*"/>
                                <RowDefinition Height="Auto"/>
                            </Grid.RowDefinitions>
                            <Border Grid.Row="0" CornerRadius="3"
                                    Background="#0a0a1a" ClipToBounds="True">
                                <Image Source="{Binding Snapshot}"
                                       Stretch="UniformToFill"
                                       RenderOptions.BitmapScalingMode="LowQuality"/>
                            </Border>
                            <TextBlock Grid.Row="1" Foreground="#a0a0b0" FontSize="10"
                                       HorizontalAlignment="Center"
                                       Margin="0,2,0,0"
                                       TextTrimming="CharacterEllipsis">
                                <Run Text="{Binding Name, Mode=OneWay}"/><Run Text=" "/><Run Text="{Binding HotkeyLabel, Mode=OneWay}" Foreground="#6a6a7a" FontWeight="SemiBold"/>
                            </TextBlock>
                        </Grid>
                    </Border>
                </DataTemplate>
            </ItemsControl.ItemTemplate>
        </ItemsControl>
    </Border>
 </UserControl>
@@ -0,0 +1,21 @@
 using System.Windows;
 using System.Windows.Controls;
 using System.Windows.Input;
 using ytLive.Models;
 using ytLive.ViewModels;
 namespace ytLive.Controls;
 public partial class SceneThumbnailStrip : UserControl
 {
    public SceneThumbnailStrip()
    {
        InitializeComponent();
    }
    private void Thumbnail_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
    {
        if (sender is Border { DataContext: Scene scene } && DataContext is MainViewModel vm)
            vm.TransitionToScene(scene);
    }
 }
@@ -0,0 +1,133 @@
 <UserControl x:Class="ytLive.Controls.TopBar"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:helpers="clr-namespace:ytLive.Helpers"
             x:Name="TopBarRoot">
    <Grid>
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="Auto"/>
            <ColumnDefinition Width="*"/>
            <ColumnDefinition Width="Auto"/>
        </Grid.ColumnDefinitions>
        <!-- LOGO / BRAND — clicking opens the in-app About overlay; the gear sits
             a couple characters past the build stamp and opens App Settings. -->
        <StackPanel Grid.Column="0" Orientation="Horizontal" VerticalAlignment="Center"
                    Margin="0,0,24,0">
            <Button Background="Transparent" BorderThickness="0" Cursor="Hand"
                    VerticalAlignment="Center" ToolTip="About LlamaCasty"
                    Command="{Binding OpenAboutCommand}">
                <Button.Template>
                    <ControlTemplate TargetType="Button">
                        <ContentPresenter/>
                    </ControlTemplate>
                </Button.Template>
                <TextBlock FontSize="22" FontWeight="Bold" VerticalAlignment="Center">
                    <Run Text="LlamaCas" Foreground="#e0e0e0"/><Run Text="ty" Foreground="#e94560"/><Run
                        x:Name="BuildIdStamp" Text="{x:Static helpers:BuildStamp.Label}" FontSize="9"
                        BaselineAlignment="Superscript" Foreground="#8888aa"
                        ToolTipService.ToolTip="{x:Static helpers:BuildStamp.Label}"/><Run Text=" " FontSize="4"/>
                </TextBlock>
            </Button>
            <!-- Settings gear (user directive): a couple characters beyond the brand,
                 nudged right a couple more places 2026-09-22 (build 77 feedback).
                 Moved up from the bottom bar — one menu: App Settings / Bug / Feature / About. -->
            <Button Style="{StaticResource IconButton}" Margin="18,0,0,2" VerticalAlignment="Center"
                    ToolTip="Menu" Click="GearButton_Click">
                <Button.ContextMenu>
                    <ContextMenu DataContext="{Binding PlacementTarget.DataContext, RelativeSource={RelativeSource Self}}">
                        <MenuItem Header="App Settings" Command="{Binding OpenSettingsCommand}"/>
                        <Separator/>
                        <MenuItem Header="Report Bug" Command="{Binding OpenBugCommand}"/>
                        <MenuItem Header="Feature Request" Command="{Binding OpenFeatureCommand}"/>
                        <MenuItem Header="About" Command="{Binding OpenAboutCommand}"/>
                    </ContextMenu>
                </Button.ContextMenu>
                <Path Data="M19.43,12.98c0.04,-0.32 0.07,-0.65 0.07,-0.98c0,-0.33 -0.03,-0.66 -0.07,-0.98l2.11,-1.65c0.19,-0.15 0.24,-0.42 0.12,-0.64l-2,-3.46c-0.12,-0.22 -0.38,-0.31 -0.61,-0.22l-2.49,1c-0.52,-0.4 -1.08,-0.73 -1.69,-0.98l-0.38,-2.65C14.46,2.18 14.25,2 14,2h-4c-0.25,0 -0.46,0.18 -0.49,0.42l-0.38,2.65c-0.61,0.25 -1.17,0.59 -1.69,0.98l-2.49,-1c-0.23,-0.09 -0.49,0 -0.61,0.22l-2,3.46c-0.13,0.22 -0.07,0.49 0.12,0.64l2.11,1.65c-0.04,0.32 -0.07,0.65 -0.07,0.98c0,0.33 0.03,0.66 0.07,0.98l-2.11,1.65c-0.19,0.15 -0.24,0.42 -0.12,0.64l2,3.46c0.12,0.22 0.38,0.31 0.61,0.22l2.49,-1c0.52,0.4 1.08,0.73 1.69,0.98l0.38,2.65c0.03,0.24 0.24,0.42 0.49,0.42h4c0.25,0 0.46,-0.18 0.49,-0.42l0.38,-2.65c0.61,-0.25 1.17,-0.59 1.69,-0.98l2.49,1c0.23,0.09 0.49,0 0.61,-0.22l2,-3.46c0.12,-0.22 0.07,-0.49 -0.12,-0.64L19.43,12.98zM12,15.5c-1.93,0 -3.5,-1.57 -3.5,-3.5c0,-1.93 1.57,-3.5 3.5,-3.5c1.93,0 3.5,1.57 3.5,3.5C15.5,13.93 13.93,15.5 12,15.5z"
                      Fill="#a0a0b0" Width="18" Height="18" Stretch="Uniform"/>
            </Button>
        </StackPanel>
        <!-- Session surface (top bar redesign): the bar is ONE surface rendered by
             the FIRST decision — Record or Stream. Each world is the whole bar; the
             other world never exists on screen. While running, the bar drops to a
             reality line + End so nothing mid-session can be re-armed. -->
        <StackPanel Grid.Column="1" Orientation="Horizontal"
                    HorizontalAlignment="Center" VerticalAlignment="Center">
            <!-- IDLE: the mode switch + the action(s) of the armed world. The three
                 controls share one height (build 77 feedback) so they read as one
                 family — segments host, Start/Go Live, and Test all sit at 32. -->
            <StackPanel Orientation="Horizontal"
                        Visibility="{Binding ShowIdleWorld, Converter={StaticResource BoolToVis}}">
                <Border Background="#0f1622" CornerRadius="4" Padding="2" Height="32" VerticalAlignment="Center">
                    <StackPanel Orientation="Horizontal">
                        <ToggleButton Style="{StaticResource SegmentToggle}"
                                      IsChecked="{Binding RecordPillOn}">
                            <TextBlock Text="REC" Style="{StaticResource SegmentLabel}"/>
                        </ToggleButton>
                        <ToggleButton Style="{StaticResource SegmentToggle}"
                                      IsChecked="{Binding OnAirPillOn}">
                            <TextBlock Text="ON-AIR" Style="{StaticResource SegmentLabel}"/>
                        </ToggleButton>
                    </StackPanel>
                </Border>
                <!-- Go face names the world: "Start Recording" vs "Go Live".
                     (Signed-out ON-AIR Start routes to the sign-in — StartSession.) -->
                <Button Content="{Binding PrimaryStartButtonLabel}" Style="{StaticResource YtButton}"
                        Height="32" Margin="10,0,0,0" Command="{Binding StartStreamCommand}"
                        Visibility="{Binding ShowPrimaryStartButton, Converter={StaticResource BoolToVis}}"/>
                <!-- Test is a child of Stream — a dry-run of the livestream, so it
                     exists only inside the Stream world (stream armed + signed in). -->
                <Button Content="Test" Style="{StaticResource YtButtonSecondary}" Padding="12,4" FontSize="11"
                        Height="32" Margin="8,0,0,0" VerticalAlignment="Center"
                        Command="{Binding StartTestCommand}"
                        ToolTip="Run a private test broadcast to check your chat overlay."
                        Visibility="{Binding ShowTestButton, Converter={StaticResource BoolToVis}}"/>
            </StackPanel>
            <!-- RUNNING: one reality line (dot + word + elapsed) and the stop -->
            <StackPanel Orientation="Horizontal"
                        Visibility="{Binding RunningVisible, Converter={StaticResource BoolToVis}}">
                <Ellipse Width="12" Height="12" VerticalAlignment="Center"
                         Fill="{Binding RunningDotBrush}"/>
                <TextBlock Text="{Binding RunningText}" FontSize="16" FontWeight="Bold"
                           Foreground="White" Margin="8,0,0,0" VerticalAlignment="Center"/>
                <TextBlock Text="{Binding LiveElapsedText}" Foreground="White" FontSize="14"
                           FontFamily="Consolas" VerticalAlignment="Center" Margin="8,0,0,0"/>
                <Button Content="{Binding EndButtonText}" Style="{StaticResource YtButton}"
                        Background="#333" Margin="14,0,0,0" Command="{Binding EndStreamCommand}"/>
            </StackPanel>
        </StackPanel>
        <!-- Account zone: lives only in the Stream world. Signed out → Sign In;
             signed in → a big avatar of the streaming account (build 77 feedback:
             "make the user icon much bigger"). Record world has no YouTube
             identity at all. -->
        <StackPanel Grid.Column="2" Orientation="Horizontal" VerticalAlignment="Center">
            <Button Content="Sign In" Style="{StaticResource YtButtonSecondary}"
                    Margin="0,0,8,0" Command="{Binding SignInCommand}"
                    ToolTip="Sign in to YouTube to go live."
                    Visibility="{Binding ShowSignInButton, Converter={StaticResource BoolToVis}}"/>
            <Button Style="{StaticResource IconButton}" Margin="0,0,0,0"
                    ToolTip="{Binding AccountDisplayName}"
                    Visibility="{Binding ShowAvatarButton, Converter={StaticResource BoolToVis}}">
                <Button.ContextMenu>
                    <ContextMenu>
                        <MenuItem Header="Change Account" Command="{Binding ChangeAccountCommand}"/>
                        <Separator/>
                        <MenuItem Header="Logout" Command="{Binding LogoutCommand}"/>
                    </ContextMenu>
                </Button.ContextMenu>
                <Border Width="40" Height="40" CornerRadius="20" Background="#16213e"
                        ClipToBounds="True" BorderBrush="#3a4a66" BorderThickness="1">
                    <Grid>
                        <Image x:Name="AvatarImage" Stretch="UniformToFill"/>
                        <TextBlock x:Name="AvatarInitial" Foreground="#e0e0e0" FontSize="20"
                                   FontWeight="Bold" HorizontalAlignment="Center" VerticalAlignment="Center"
                                   Visibility="Collapsed"/>
                    </Grid>
                </Border>
            </Button>
        </StackPanel>
    </Grid>
 </UserControl>
@@ -0,0 +1,85 @@
 using System;
 using System.IO;
 using System.Net.Http;
 using System.Windows;
 using System.Windows.Controls;
 using System.Windows.Media.Imaging;
 using ytLive.Helpers;
 using ytLive.ViewModels;
 namespace ytLive.Controls;
 public partial class TopBar : UserControl
 {
    private static readonly HttpClient AvatarHttp = new() { Timeout = TimeSpan.FromSeconds(15) };
    private string? _loadedAvatarUrl;
    public TopBar()
    {
        InitializeComponent();
        AvatarImage.Source = null;
        AvatarInitial.Visibility = System.Windows.Visibility.Collapsed;
    }
    public void RefreshAvatar()
    {
        _ = LoadAvatarImageAsync();
    }
    private void GearButton_Click(object sender, RoutedEventArgs e)
    {
        // One menu (Settings / Bug / Feature / About), opened on click — moved up
        // from the bottom bar so app-level actions live next to the brand.
        if (sender is Button { ContextMenu: { } menu } button)
        {
            menu.PlacementTarget = button;
            menu.Placement = System.Windows.Controls.Primitives.PlacementMode.Bottom;
            menu.IsOpen = true;
        }
    }
    private async System.Threading.Tasks.Task LoadAvatarImageAsync()
    {
        var vm = DataContext as MainViewModel;
        var url = vm?.AccountAvatarUrl;
        if (vm is not { IsConnected: true })
        {
            ShowAvatarFallback(null);
            return;
        }
        if (string.IsNullOrWhiteSpace(url))
        {
            AppLog.Write("Avatar: connected but no profile image URL on the session");
            ShowAvatarFallback(null);
            return;
        }
        if (url == _loadedAvatarUrl && AvatarImage.Source != null) return;
        try
        {
            var bytes = await AvatarHttp.GetByteArrayAsync(url);
            using var ms = new MemoryStream(bytes);
            var bitmap = new BitmapImage();
            bitmap.BeginInit();
            bitmap.CacheOption = BitmapCacheOption.OnLoad;
            bitmap.StreamSource = ms;
            bitmap.EndInit();
            bitmap.Freeze();
            _loadedAvatarUrl = url;
            AvatarImage.Source = bitmap;
            AvatarInitial.Visibility = System.Windows.Visibility.Collapsed;
        }
        catch (Exception ex)
        {
            AppLog.Write($"Avatar load failed ({url}): {ex.Message}");
            ShowAvatarFallback(vm?.AccountDisplayName);
        }
    }
    private void ShowAvatarFallback(string? name)
    {
        _loadedAvatarUrl = null;
        AvatarImage.Source = null;
        AvatarInitial.Text = string.IsNullOrWhiteSpace(name) ? "?" : name.Substring(0, 1).ToUpperInvariant();
        AvatarInitial.Visibility = System.Windows.Visibility.Visible;
    }
 }
@@ -0,0 +1,61 @@
 # Controls — index
 The phase-2 carved pieces of what used to be one monolithic `MainWindow.xaml`
 (1,681 lines → a 123-line shell). Each is a `UserControl` in the `ytLive.Controls`
 namespace, extracted one roll-back commit at a time (refactor-commit-12..18).
 See [`schema.md`](../schema.md) for the memory-map conventions.
 | File | Purpose |
 |------|---------|
 | `BottomBar.xaml(.cs)` | Footer (Row 3): stream stats (bitrate/fps/dropped/duration/health), resolution dropdown (gear menu moved up to TopBar 2026-09-22) |
 | `HealthBanner.xaml(.cs)` | Row 1 status banner + the 7 value→visibility converters live in the app theme, not here |
 | `TopBar.xaml(.cs)` | Row 0 session surface (2026-09-22 redesign): brand + gear menu (left), one segmented REC|ON-AIR mode switch + world actions (Record: Start Recording · Stream: Go Live + Test) + reality line while running (dot/word/elapsed) + End (center), account zone — Sign In or avatar w/ Change Account/Logout context menu (right). `RefreshAvatar()`, `GearButton_Click` |
 | `PreviewPane.xaml(.cs)` | Row 1 Col 1 center: the 1920×1080 `OverlayCanvas`/`SelectionOverlay`/`BrandFlashLayer`/`SocialBarElement`, text pull-out drawer, and the live-controls row (TRAX / game / mic meters + sliders + speakers + socials) |
 | `SceneThumbnailStrip.xaml(.cs)` | Row 0 scene-picker strip (`ItemsControl` over `Scenes`), staged-red / live-green border highlight |
 | `LeftPanel.xaml(.cs)` | Row 1 Col 0 left panel: edit mode → layers+properties; live → YouTube chat. Source add/edit/remove, list drag-to-reorder, snapshot revert-accept |
 | `OverlayHost.xaml(.cs)` | Root-grid overlay dialogs: Settings / Report Bug / Feature Request / About (+ licenses + license-key entry). `BackToAbout_Click` lives here |
 | `SceneThumbnailStrip.xaml.cs` | Code-behind for the strip above |
 | `LeftPanel.xaml.cs` | Code-behind for the panel above |
 ## Window ↔ control contract
 The shell (`MainWindow.xaml(.cs)`) wires up each control and routes the few
 cross-cutting calls through it:
 - Ctor finds each control by `x:Name` (`TopBar`, `PreviewPane`, `LeftPanel`)
  AFTER `InitializeComponent`, **before** any method touches it (null-ref guard).
 - `_previewPane.IsClickInsidePreview/Drawer` + `_leftPanel.IsClickInside` →
  deselection guard in `Window_PreviewMouseLeftButtonDown`.
 - `_previewPane.UpdateSelectionOverlay(bool)` + `_leftPanel.OnSelectionChanged(vm)`
  → selection/edit-mode routing from the VM's `SelectedElement` change.
 - `_topBar.RefreshAvatar()` on `IsConnected`/`AccountAvatarUrl` change.
 - Handlers in moved controls cast `(DataContext as MainViewModel)` — controls
  inherit the window's DataContext; never pass the VM through a property.
 ## Gotchas learned the hard way
 - **A UserControl cannot see `Window.Resources`** (StaticResource resolves by
  element lookup, so it stops at the control boundary). The 7 converters
  (`BoolToVis`, `InverseBoolToVis`, `NotNullToVis`, `NullToVis`, `HiddenBoolToVis`,
  `EnumToBool`, `AllTrueToVis`) were promoted from `MainWindow.Resources` into
  `Themes/Controls.xaml` (see [`Themes/index.md`](../Themes/index.md)).
 - **Moved XAML can lose its namespace**: a block cut from MainWindow carries no
  root xmlns, so any `models:`/`Helpers:` ref in it breaks the build with
  `MC2000: Value cannot be null (key)`. Declare `xmlns:models` / `xmlns:Helpers`
  on each control's root (LeftPanel hit this).
 - **Name-looked-up host stubs must stay in the window**, not a control:
  `WebViewHostPanel` (ctor `InitWebView2(WebViewHostPanel)`) and `ToastArea`
  (`NotificationService.InArea("ToastArea")`) are resolved by name from the
  window root — so `OverlayHost` deliberately leaves them as thin window-root
  children (Commit 18). Since the 2026-09-14 composition-capture redesign only
  `ToastArea` remains — `WebViewHostPanel` is deleted (web sources no longer
  host a multiline XAML control; `InitWebView2()` runs from `MainWindow_Loaded`
  with no panel argument).
 - When cutting visual wrappers, don't drop the outer `Border`'s
  background/glow/margin — Commit 15 initially lost the preview's outer border
  and had to restore it same-commit.
 Related: [`ViewModels/index.md`](../ViewModels/index.md) (MainViewModel the
 controls bind to), [`Themes/index.md`](../Themes/index.md) (styles/converters),
 [`Helpers/index.md`](../Helpers/index.md) (ViewModelBase, converters), the
 `MainWindow.xaml` shell at repo root that hosts these.
@@ -1,12 +1,42 @@
 # Distribution & IP Protection Plan
-> 360-degree protection strategy for LlamaCasty (.NET 8 / WPF), built around Polar.sh.
+> 360-degree protection strategy for LlamaCasty (.NET 8 / WPF).
 > ## ⛔ SUPERSEDED IN PART — 2026-09-27
 >
 > **Distribution is now the Microsoft Store: MSIX package + Store IAP.** The creator's criteria
 > were *"zero headaches, minimal maintenance (for me) while still providing accountability and
 > a reasonably easy upgrade flow"*, and that ruling deleted this document's central premise.
 >
 > **What still stands below:** §1 (code architecture / IP protection), §5 (obfuscation posture),
 > §6 (legal), §7 (hardening) — those are about protecting the *binary*, and an MSIX package is
 > still a binary. **§1.2's build-posture ceiling (HARDENED + MOCK_REWARDS, additive-only)
 > remains the agreed ceiling.**
 >
 > **What is dead:**
 > - **Polar as the distribution backbone** — the entire section below. Store IAP handles
 >   checkout, entitlements, refunds, tax, and the customer portal. So does **file hosting**:
 >   the Store is the delivery mechanism, so "upload `LlamaCasty.exe` to Polar as a File
 >   Download benefit" (§2) no longer exists as a step.
 > - **Code signing as our problem** — MSIX is signed by **Microsoft**. There is no certificate
 >   to buy, no HSM, no annual renewal. See §4.3, which was already corrected to say this, and
 >   `TASKS/research-store-certification.md` §2–3.
 > - **Velopack / the update URL / the DO droplet** — Store auto-update.
 >
 > **The authoritative plan is now [`TASKS/task-48-distribution-msix.md`](TASKS/task-48-distribution-msix.md).**
 > Keep this file for the protection sections; do not re-derive a delivery strategy from it.
 ---
-## Polar.sh as the Distribution Backbone
+## Polar.sh as the Distribution Backbone — ⛔ OBSOLETE (2026-09-27)
-Polar handles everything between "customer wants to pay" and "customer has a working license key." We don't build any of that. What Polar gives us:
+> **Historical record only.** Retained because the fee tables and the reasoning about *why*
 > one-time beat subscription were worth working out. **None of the "How We Use It" rows are
 > current**, with one exception worth keeping: the Merchant-of-Record point — *someone else
 > collects and remits VAT/GST* — is still true under Store IAP, because **Microsoft** is now
 > that someone. That fact alone was the strongest argument for the ruling.
 Polar handled everything between "customer wants to pay" and "customer has a working license key." We didn't build any of that. What Polar *was* going to give us:
 | Capability | How We Use It |
 |------------|---------------|
@@ -14,13 +44,15 @@ Polar handles everything between "customer wants to pay" and "customer has a wor
 | **File hosting** (up to 10GB) | Upload `LlamaCasty.exe` (self-contained, ~80-120MB) as a "File Download" benefit. Customers get signed, personal download URLs. SHA-256 checksums included. |
 | **Checkout** | Polar's hosted checkout page handles payment. No Stripe integration, no PCI scope, no custom checkout UI. |
 | **Customer portal** | Customers self-serve: view/copy license keys, see expiry, deactivate devices, rotate compromised keys. We don't build a portal. |
-| **Subscriptions** | If we go subscription model (deferred), Polar handles recurring billing, dunning, cancellation. |
+| **One-time orders** | **Chosen model (2026-09-21):** perpetual license via a one-time Polar order — no subscription. Polar also supports recurring billing if ever needed, but we do not use it. |
 | **Merchant of Record** | Polar collects and remits VAT/GST/sales tax globally. We never touch tax compliance. |
 | **Webhooks** | Polar notifies our backend on purchase, cancellation, key rotation. Used for optional telemetry (section 6.3). |
-**Polar pricing (2026):** 5% + $0.50 per transaction (Starter plan). No monthly fee.
+**Polar pricing (2026):** 5% + $0.50 per transaction (Starter plan). No monthly fee. ⛔ *No
 longer paid to anyone — the equivalent cost is now inside the Store revenue share, whose rate
 is unverified (see `TASKS/research-store-certification.md` §11).*
-**What Polar does NOT handle:** Obfuscation, code signing, anti-tamper, runtime protection, EULA, DMCA. That's all us — sections 1-3, 5-7 below.
+**What Polar did NOT handle:** Obfuscation, code signing, anti-tamper, runtime protection, EULA, DMCA. That's all us — sections 1-3, 5-7 below.
 ---
@@ -286,11 +318,19 @@ Single-file means everything is inside the `.exe`. No DLLs, no runtime dependenc
 **Caveat:** Self-contained single-file means ~80-120MB due to bundled .NET runtime. For smaller size, use framework-dependent publishing (requires .NET 8 runtime on user machines) — drops to ~5-10MB.
-### 4.2 Distribution via Polar
+### 4.2 Distribution via Polar — ⛔ OBSOLETE (2026-09-27)
-**Product setup on Polar:**
+> **Superseded by Microsoft Store MSIX + Store IAP** (ruling in
 > `TASKS/task-48-distribution-msix.md` item 0). The Store re-signs, hosts, updates, and takes
 > payment — so file hosting, license keys, checkout, the customer portal, device deactivation and
 > key rotation are **all** handled by Microsoft and none of it needs building. Retained below as a
 > record of the model that was designed and abandoned. ⚠️ **The `$29`/`$49` one-time prices in this
 > section are dead** — the settled pricing is **`$10/mo` or `$400` lifetime**, net of a verified
 > 15% Store share.
-1. Create a product: "LlamaCasty" — one-time purchase (or subscription if deferred).
+**Product setup on Polar (as designed, never shipped):**
 1. Create a product: "LlamaCasty" — **one-time purchase** (perpetual license; $29 founder / $49 list).
 2. Add two benefits:
   - **License Key** — brandable prefix `LLAMA-****`, activation limit (e.g., 3 devices), optional expiry.
   - **File Download** — upload the signed `LlamaCasty.exe` (~80-120MB). Polar generates signed, personal download URLs. SHA-256 checksum included.
@@ -313,9 +353,43 @@ Single-file means everything is inside the `.exe`. No DLLs, no runtime dependenc
 - If a key is compromised, customer or merchant can rotate it via Polar.
 - Previous key stops validating immediately. Status, usage, limits, expiry preserved.
 **What the Store does instead:** the customer installs from the Store listing, pays through Store
 checkout, and the app reads the entitlement the OS already holds. There is no key to enter, no
 activation call, no portal to visit, and no offline-grace period to maintain — which also retires
 the whole "network flaky → app thinks I'm expired" bug class in §4.5.
 ### 4.3 Code Signing
-**Certificate:** Buy an EV (Extended Validation) code-signing certificate from DigiCert or Sectigo ($200-400/year). EV certificates get instant SmartScreen reputation; DV/OV certs trigger SmartScreen warnings for months.
+> ⚠️ **The cert choice below is a live decision, and the old plan's EV recommendation is
 > dead.** Microsoft **removed the SmartScreen instant-bypass for EV certificates in March
 > 2024** — an EV-signed file now accrues reputation exactly like an OV-signed one, so paying
 > $400+/yr buys precisely what paying ~$150 buys. **Do not buy EV.**
 >
 > **But the more interesting finding is that you may not need a certificate at all.** Three
 > costs, current as of 2026-09-27:
 >
 > | Route | Cert/yr | SmartScreen | Note |
 > |---|---|---|---|
 > | **Microsoft Store (MSIX)** | **$0** — Microsoft re-signs | **No warning** | Requires MSIX packaging; Store review; public listing |
 > | **Microsoft Store (EXE/MSI)** | $120–300 — *your* cert | Warning ramp | Store does **not** re-sign; silent install mandatory. Strictly dominated — cert required anyway |
 > | **Direct + OV cert** | $150–300 | Warning ramp | Worldwide availability |
 > | **Direct + Azure Artifact Signing** | ~$9.99/mo ≈ $120 | Warning ramp | **Individuals: USA/Canada only.** Identity validation required |
 >
 > Signing does **not** clear the warning on day one either way: a valid cert stops the
 > *malware* warning immediately, but "unrecognized publisher" clears as SmartScreen accrues
 > reputation from real download volume. Budget cert validity at **460 days** (CA/B Forum
 > CSC-31) — this is a recurring line item, not a one-time purchase — and note that private
 > keys must sit on an **HSM or hardware token**.
 >
 > **The full comparison, the four real combinations, and the policy analysis live in
 > [`TASKS/research-store-certification.md`](TASKS/research-store-certification.md) §2–3.
 > The executable checklist is [`TASKS/task-48-distribution-msix.md`](TASKS/task-48-distribution-msix.md),
 > and the route decision is the creator's.**
 **Certificate:** Buy an **OV (Organization Validation)** code-signing certificate from DigiCert
 or Sectigo (~$150–300/year), or an **Azure Artifact Signing** profile (~$9.99/month,
 USA/Canada individuals only) if the geography allows. ⛔ **Not EV** — no SmartScreen benefit
 since March 2024. **Or buy nothing at all** if the route is the Microsoft Store.
 **Signing process:**
 ```powershell
@@ -332,7 +406,13 @@ Set-AuthenticodeSignature -FilePath "LlamaCasty.exe" `
 **Storage:** Certificate `.pfx` file stored in GitHub Secrets (or Azure DevOps secure files). Never committed to the repo.
-### 4.4 Update Mechanism
+### 4.4 Update Mechanism — ⛔ OBSOLETE (2026-09-27)
 > **Superseded by Store updates.** Microsoft delivers and updates the app from the listing, so
 > there is nothing to check and no manifest to host. The Velopack updater currently in
 > `App.xaml.cs` **downloads *and executes***, which Store policy **10.2.2** does not permit — its
 > removal is a **compliance action**, not optional cleanup (TASK 48 item 3). The Polar-native design
 > below is retained as a record of the approach that was rejected; it is not an option.
 **Polar-native approach (no custom infrastructure):**
@@ -367,10 +447,18 @@ public class UpdateCheckService
 - Download link points to Polar's customer portal (not direct download).
 - This adds one external dependency (GitHub) but keeps Polar as the source of truth.
-### 4.5 Licensing Logic (already implemented)
+### 4.5 Licensing Logic — ⛔ BEING DELETED (2026-09-27)
 > ⚠️ **"Already implemented" was true as of 2026-09-21 and is no longer.** `PolarLicenseService`
 > and `Helpers/PolarLicense.cs` are being **removed** as part of the TASK 10 teardown (TASK 48 item 0).
 > Store IAP replaces the whole validation hop: `IsPremium` is derived from the **OS-supplied Store
 > entitlement**, so there is no network call, no key, and — importantly — **no 14-day offline-grace
 > machine to protect**, which retires the entire "network flaky → app thinks I'm expired" bug class.
 > What survives is only `IsPremium` → `BrandFlashEnabled = !value`. Retained below as the record of
 > what shipped and why it no longer applies.
 ```csharp
-// Services/PolarLicenseService.cs — already ships
+// Services/PolarLicenseService.cs — shipped under Polar; being deleted
 // Calls Polar's customer-portal validation endpoint (no auth required)
 // Survives obfuscation — property names excluded via [Obfuscation(Exclude = true)]
 [Obfuscation(Exclude = true)]
@@ -383,11 +471,11 @@ public class LicenseValidationResult
 }
 ```
-**What's already done:**
+**What shipped under Polar (now being deleted):**
- `PolarLicenseService` validates keys against Polar API.
+- `PolarLicenseService` validated keys against the Polar API.
- `OrganizationId` is hardcoded (safe — it's public knowledge, tied to our Polar account).
+- `OrganizationId` was hardcoded.
- License state persists in `LayoutStore.Settings` (SQLite) with offline grace period.
+- License state persisted in `LayoutStore.Settings` (SQLite) with an offline grace period.
- `PremiumUrl` points to Polar checkout.
+- `PremiumUrl` pointed to Polar checkout.
 **What survives obfuscation:** The validation logic in `Services.dll` is obfuscated. An attacker who decompiles the exe sees only the UI calling an interface — the actual Polar API call is in the obfuscated DLL.
@@ -1,88 +1,60 @@
-# HANDOFF — Session State
+# HANDOFF — 2026-10-08 (zoom box shipped, READY FOR PUSH)
-## Branch / Commit State
+## Branch
 - main (no feature branch)
-**`main`**, working tree is **CLEAN**.
+## Push readiness
 - **5 commits ahead of origin/main, clean to push** (fetch confirmed origin has not moved):
  `966e718` zoom box visuals → `4b3d82f` zoom as layered + TASK 51 booking → `6bff21b`
  anchored-capture rework → `948dd08` dims-shading fix → (docs unit: TASK 52 record +
  numbering fixes + this HANDOFF).
 - The pinned-chat work unit below is **uncommitted on purpose** — `git push` sends only
  commits, so pushing is safe; the dirty files stay local.
-Commits `46978b8` (AGENTS push policy), `fc33022` (HANDOFF), and refactor
+## Dirty files (NOT mine — the in-flight "pinned chat" work unit; do NOT commit or co-edit)
-commits `0–5` through `e286719` are **pushed** (incl. `refactor-commit-0..5`).
+- `Models/YouTube.cs`
-Refactor commits **6–11 are LOCAL ONLY** (policy 2026-08-30: no per-commit
+- `ViewModels/MainViewModel.Chat.cs`
-push; `git push --tags` only at a user-agreed milestone / "push it"):
+- `Controls/LeftPanel.xaml` (pinned-message UI)
 - Untracked: `Helpers/RelayCommandGeneric.cs`
-| Commit | Hash | Tag | Partial | Lines |
+## What just happened (2026-10-08, third zoom pass — dims shading)
-|--------|------|-----|---------|-------|
+The zoom box shipped as a **loupe** (`4b3d82f`), then was corrected to an **anchored-capture
-| 6 Audio | `c1126a5` | `refactor-commit-6` | `MainViewModel.Audio.cs` | 408 |
+magnifier over the full composite drawn last** (commit `6bff21b`). The final correction: as the box
-| 7 Trax | `535a501` | `refactor-commit-7` | `MainViewModel.Trax.cs` | 132 |
+is dragged, the dim rectangles (55% black "div shading" around the box) were sliding under the
-| 8 Socials | `c41ff7f` | `refactor-commit-8` | `MainViewModel.Socials.cs` | 161 |
+capture region — shown inside the box because its `VisualBrush` samples all of `CanvasGrid`, and the
-| 9 Streaming | `e1006a0` | `refactor-commit-9` | `MainViewModel.Streaming.cs` | 787 |
+`DimRects` ItemsControl previously lived INSIDE `CanvasGrid`.
 | 10 Chat | `3b77a13` | `refactor-commit-10` | `MainViewModel.Chat.cs` | 194 |
 | 11 Overlays | `1efde5a` | `refactor-commit-11` | `MainViewModel.Overlays.cs` | 194 |
-Nightly summary: **Phase 1 complete.** The plan was 11 partials + scaffold;
+Fix: the `DimRects` overlay is now a **sibling of `CanvasGrid`** (renders above the composed
-all live in `ViewModels/`. Core `MainViewModel.cs` shrank 1,890 → **758
+content, below the `ZoomBox`), never a descendant — so the zoom sample can never pick up the shading
-lines**. Every change: clean build (0 warnings), `scripts/verify.sh` (246
+and the captured area stays clear no matter where the box is dragged. Behavior consequence to note:
-passed + 2 known failures only), `scripts/scope-check.sh` with explicit file
+in non-zoom ("quality dims") mode the dims now also shade the global overlays (brand flash, alert
-args, `ViewModels/index.md` updated in the SAME commit, tagged
+ticker, social bar) that sit above them in the old tree — consistent with "chrome outside the crop
-`refactor-commit-N`, no per-commit push.
+is dimmed". Structural invariant added to `ZoomBoxInteractionTests`: `DimRectsLayer` is a direct
 child of `PreviewCanvas`, not inside `CanvasGrid`, and renders below the `ZoomBox`.
-## What's In Flight
+## Zoom feature state
 - **TASK 52 (zoom box) is now a first-class record** — see [`TASKS/task-52-zoom-box.md`](TASKS/task-52-zoom-box.md):
  feature provenance + the three creator corrections, shapes, implementation map, tests.
  TASK 51 (webcam background Remove + Blur) is unblocked for the next unit.
 - Models: `ZoomState.cs`, `ZoomShape.cs` (Circle/VerticalRectangle/HorizontalRectangle), `ZoomSceneElement.cs`.
 - ViewModel (`MainViewModel.Zoom.cs`): `ActivateZoom`/`ToggleZoom`/`DismissZoom`/`StartZoomMove`/`UpdateZoomMove`/`EndZoomMove` + `RebuildDimRectsForZoom`; transient element healed/mirrored by `HealZoomLayers`/`EnsureZoomLayer`.
 - Output: box composited last via `BlitZoom`/`ZoomMagnifier`; output crop = tier (box never the crop).
 - Preview: `ZoomBox` + `DimRectsLayer` are both SIBLINGS of `CanvasGrid` (box above dims above content); box samples the full composite at the fixed capture, 2x; circle→ellipse clip, rect/square outline per shape; `LeftPanel` hides the placeholder row via `IsZoomLayer`.
 - Rectangle shape = 4:3; Circle square; Phone 9:16. Capture anchored on click (`CaptureX/Y`); dragging the box never changes it.
-Nothing code-in-flight — working tree clean, Phase 1 done.
+## Tests
 - Full suite: **406 passed / 0 failed** on a clean full run (the pre-existing audio-loopback timing
  flake and `RealMouseDrag`'s interactive-desktop requirement recur occasionally — not zoom
  regressions). Zoom tests 3/3 green, 0 build warnings.
-**Next (queued, not started): Phase 2 — split `MainWindow.xaml` (1,681 lines)
+## Known issues / follow-ups
-into UserControls.** Same rules: one work unit per control, docs in the same
+- **Background "Use default background" toggle still not working** (carried from 2026-10-07):
-commit, verify + scope-check, commit locally, `git push` only on user go.
+  binding exists (`UseDefaultBackground`), VM handler invalidates bake; investigate when time permits.
 - The 3px selection / crop-outline strokes could still show in the zoom box IF the capture overlaps
  them in edit mode — not shading, thin outlines only; the dims (the user's complaint) are gone.
-**Push pending:** refactor commits 6–11 + their tags are local. The Session-1
+## Next step
-push checkpoint was never reached because the user directive was to run the
+- User runs the app live to eyeball: drag the zoom box anywhere and the captured content stays clean
-series to completion; Phase 1 completion is the natural milestone to push on
+  (no dim shading in the box; the scene outside the box stays dimmed). Then TASK 51 (webcam
-explicit user confirmation.
+  background Remove + Blur) per `TASKS/task-51-webcam-bg-effects.md`, and the background-toggle
-
+  investigation if still open.
 ## Landmines
 - **Pre-existing test failures (do not chase):**
  `AudioPipelineTests.Mix_HonorsProviderGains_AndGameMute_KillsTheLoopback` +
  `RoundClipInteractionTests.Round_Clip_Corner_Is_Grabbable_And_Shape_Is_Circle`.
 - **Tests occasionally abort early (236/237)** — known flake, accepted by `verify.sh`.
 - **App running locks `ytLive.exe`** → build fails MSB3027. Kill PID before building.
 - **Implicit usings are SDK-default but partials must still carry their own
  domain usings** (they do not inherit core's): `ICommand`/`ObservableCollection`/
  `WriteableBitmap`/`DispatcherTimer` etc. are NOT implicit. Grep-verified usings:
  - Audio: Input, Media, Threading, `NAudio.CoreAudioApi`, `ytLive`, Helpers, Models, Services, Services.Audio
  - Trax: IO, Media, `Microsoft.Win32`, Helpers, Models, Services.Audio
  - Socials: Windows, Input, Media, `ytLive`, Helpers, Models, Services, Services.Compositor
  - Streaming: ObjectModel, IO, Windows, Input, Threading, `Microsoft.Win32`, Helpers, Models, Services, Services.Encoder
  - Chat: ObjectModel, Media, Media.Imaging, Threading, Helpers, Models, Services
  - Overlays: Diagnostics, IO, Input, Helpers
 - **Pre-commit gate:** `scripts/verify.sh` (0-warning build + full tests) and
  `scripts/scope-check.sh "file1" …` — scope-check REQUIRES explicit file args.
 - Build from WSL with the Windows dotnet host only (see `AGENTS.md`).
 ## Todo state
 - MainViewModel refactor: **Phase 1 complete (11/11 partials + scaffold).**
  `ViewModels/index.md` has a per-partial table row (code↔commit map in the
  tracker section). Core row now describes only what remains (ctor wiring,
  lifecycle, source commands, WebView2 hosting, frame-pump seam,
  `SelectedElement`, `BrandFlash*`, `BuildCompositorOptions`/`ResolveOutputFrame`).
 - TASK 3: 27/30 (preview compositor 16, text source 17, alerts 20 still open).
 - TASK 4: ✅ shipped. TASK 9: items 1–3 shipped; 4–7 open. TASK 10: steps 1–7; Velopack pending.
 - TASK 18: shipped, creator verification pending. TASK 19/23, 20, 21-A: shipped.
 - TASK 22 (audio sync offset): not started — required for v1.
 - Monitoring: cross-partial private access is the point of partial classes —
  no moved member re-declared anywhere; moved setters reference other partials
  purely by name.
 ## Session summary (2026-08-30)
 - Ran the MainViewModel split to completion under the standing directive
  ("continue until you can continue no longer" — no interruption prompts).
 - Commits 9 (Streaming), 10 (Chat), 11 (Overlays) landed locally, each ~8:40
  back-to-back: cut → 0-warning build → verify (246 pass + 2 known) →
  scope-check → index.md in-commit → `git tag refactor-commit-N`. No push.
 - Streaming was the hardest cut (interleaved props, master-frame consts,
  session timer, health pipeline, record rename-on-stop); Chat and Overlays
  were clean contiguous cuts. One build fix each: Streaming needed
  `ObjectModel`/`Input`, Chat needed `Media.Imaging` for `WriteableBitmap`.
 - Docs kept honest throughout: `index.md` rows for Streaming/Chat/Overlays,
  About-hub row re-pointed to the Overlays partial, core row trimmed each time.
@@ -5,15 +5,13 @@ namespace ytLive.Helpers;
 /// <summary>
 /// Minimal file logger used to diagnose startup/shutdown crashes on Windows,
 /// where the WPF app has no visible console. Writes to
-/// %APPDATA%\ytLlive\startup.log, appending synchronously so entries survive
+/// %APPDATA%\ytLlive\startup.log (or a per-instance subfolder in DEBUG — see
-/// a hard crash.
+/// InstanceProfile), appending synchronously so entries survive a hard crash.
 /// </summary>
 public static class AppLog
 {
    private static readonly string LogPath = Path.Combine(
-        Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData),
+        InstanceProfile.DataRoot, "startup.log");
        "ytLlive",
        "startup.log");
    private static readonly object Gate = new();
@@ -0,0 +1,123 @@
 using System;
 using System.Diagnostics;
 namespace ytLive.Helpers;
 /// <summary>
 /// Arrival cadence for one window of a timestamped frame stream: how many frames
 /// arrived, how far apart they were, and how many gaps were long enough to read
 /// as a hitch. Fed any shared monotonic clock (<see cref="Stopwatch.GetTimestamp"/>
 /// values, or a device's system-relative stamps on the same clock) and read through
 /// <see cref="Summarize"/>.
 ///
 /// Why it exists: a 60fps container makes a missing camera frame indistinguishable
 /// from a padded repeat. rawvideo carries no per-frame timestamps — ffmpeg stamps
 /// frames by ARRIVAL at the declared rate — so the OBS "duplicate on lag" loop
 /// (FramePump) emits 300 authored frames per 5s whether the renderer managed 300
 /// composites or 84. The recorded file therefore cannot name the stage that lost
 /// the frames; only these counters can. The same counter run twice tells the two
 /// apart: the camera's OWN timestamps vs our ARRIVAL timestamps. Steady camera
 /// stamps with ragged arrivals means WE dropped it (compositor/reader); ragged in
 /// both means the camera, USB link, or driver did.
 /// </summary>
 public sealed class FrameCadence
 {
    /// <summary>Default hitch threshold in ms. 50ms is ~1.5x a 30fps period — a
    /// missed 30fps frame arrives as ~66ms — so this counts dropped frames without
    /// flagging ordinary jitter (a 33ms frame can legitimately measure 35ms).</summary>
    public const double DefaultHitchThresholdMs = 50;
    private readonly double _hitchThresholdMs;
    private long _firstTicks;
    private long _previousTicks;
    private double _gapTicksTotal;
    private int _frames;
    private int _gaps;
    private int _hitches;
    private double _longestGapMs;
    public FrameCadence(double hitchThresholdMs = DefaultHitchThresholdMs)
    {
        if (hitchThresholdMs <= 0)
            throw new ArgumentOutOfRangeException(nameof(hitchThresholdMs), hitchThresholdMs,
                "Hitch threshold must be positive.");
        _hitchThresholdMs = hitchThresholdMs;
    }
    public int Frames => _frames;
    public int Gaps => _gaps;
    public int Hitches => _hitches;
    public double HitchThresholdMs => _hitchThresholdMs;
    /// <summary>Records one frame at <paramref name="timestampTicks"/> on the shared
    /// monotonic clock. Monotonicity is asserted, not trusted: an out-of-order stamp
    /// (a device whose clock domain differs from ours, a wrapped counter, a dropped
    /// timestamp) is counted as a frame but produces no gap AND does not become the
    /// reference for the next one — otherwise a single bad stamp would poison both
    /// its own interval and the one after it, inventing a multi-second "hitch".</summary>
    public void Add(long timestampTicks)
    {
        if (_frames == 0)
        {
            _firstTicks = timestampTicks;
            _previousTicks = timestampTicks;
            _frames++;
            return;
        }
        var delta = timestampTicks - _previousTicks;
        _frames++;
        if (delta <= 0) return;
        var gapMs = delta * 1000d / Stopwatch.Frequency;
        _gaps++;
        _gapTicksTotal += gapMs;
        if (gapMs > _longestGapMs) _longestGapMs = gapMs;
        if (gapMs >= _hitchThresholdMs) _hitches++;
        _previousTicks = timestampTicks;
    }
    public FrameCadenceSummary Summarize()
    {
        var spanMs = _frames >= 2
            ? (_previousTicks - _firstTicks) * 1000d / Stopwatch.Frequency
            : 0d;
        // Rate is gaps-per-span, not frames-per-span: N frames span N-1 periods, and
        // counting the extra interval would report one extra frame per window.
        var rate = _gaps > 0 && spanMs > 0 ? _gaps / (spanMs / 1000d) : 0d;
        return new FrameCadenceSummary(
            _frames, rate, spanMs, _gaps, _hitches, _longestGapMs,
            _gaps > 0 ? _gapTicksTotal / _gaps : 0d, _hitchThresholdMs);
    }
    /// <summary>Starts a fresh window, keeping the configured threshold.</summary>
    public void Reset()
    {
        _firstTicks = 0;
        _previousTicks = 0;
        _gapTicksTotal = 0;
        _frames = 0;
        _gaps = 0;
        _hitches = 0;
        _longestGapMs = 0;
    }
 }
 /// <summary>One measured cadence window — see <see cref="FrameCadence"/>.</summary>
 public readonly record struct FrameCadenceSummary(
    int Frames,
    double RatePerSecond,
    double SpanMs,
    int Gaps,
    int Hitches,
    double LongestGapMs,
    double AverageGapMs,
    double HitchThresholdMs)
 {
    /// <summary>One-line log form. Identical in shape from every producer (camera
    /// source, frame pump) so two lines can be read against each other: same window
    /// length, same fields, same order.</summary>
    public string Describe(string label) => Frames == 0
        ? $"{label} no frames"
        : $"{label} {Frames}f/{SpanMs / 1000d:F1}s {RatePerSecond:F1}/s, {Gaps} gaps, " +
          $"{Hitches} >= {HitchThresholdMs:F0}ms, avg {AverageGapMs:F1}ms, longest {LongestGapMs:F1}ms";
 }
@@ -0,0 +1,77 @@
 using System;
 using System.IO;
 namespace ytLive.Helpers;
 /// <summary>
 /// Which run of LlamaCasty this process is, and where its private state lives.
 /// <para><b>Dev-only affordance (creator directive, 2026-09-26).</b> Pre-1.0 the creator
 /// needs two instances side by side: one streaming, one screen-capturing the other.
 /// Two instances on one Windows profile collide on state, and two of those collisions
 /// are hard failures rather than annoyances:
 /// <list type="bullet">
 /// <item><b>The SQLite layout DB.</b> The app's model is read-whole-scene / write-whole-scene,
 /// so two instances saving different layouts clobber each other.</item>
 /// <item><b>The WebView2 user data folder.</b> Chromium takes an exclusive lock on it; the
 /// second instance of the same exe simply fails to start.</item>
 /// <item><b>The auth token store.</b> A test instance would overwrite the real YouTube
 /// sign-in.</item>
 /// <item><b>startup.log.</b> Two appenders interleave into one file, so a crash in either
 /// instance is ambiguous.</item>
 /// </list>
 /// So in <c>DEBUG</c> a process can claim an identity and gets its own private root
 /// under <c>instances\&lt;id&gt;</c>: <c>$env:YTLIVE_INSTANCE=2; dotnet run</c>.
 /// Recording, screen capture and the ffmpeg <c>tools\</c> cache are deliberately LEFT
 /// shared — the cache should be shared, and the creator chooses the record folder.
 /// Global hotkeys are also left alone: if both instances register the same one, Windows
 /// refuses the second, which is the correct answer.</para>
 /// <para><b>At 1.0 this disappears.</b> The whole implementation is inside
 /// <c>#if DEBUG</c>; a Release build compiles to the two pass-throughs at the bottom —
 /// no environment variable, no alternate folder, not even the variable's NAME in the
 /// binary. Call sites are unconditional, so Release cannot accidentally diverge: it
 /// always resolves the one real user profile.</para>
 /// </summary>
 public static class InstanceProfile
 {
 #if DEBUG
    /// <summary>Environment variable naming this instance. Absent or blank = the primary
    /// instance on the real user profile.</summary>
    public const string InstanceVariable = "YTLIVE_INSTANCE";
    /// <summary>This instance's id, or null for the primary instance.</summary>
    public static string? Id => Sanitize(Environment.GetEnvironmentVariable(InstanceVariable));
    /// <summary>Private state root: the real profile normally, a per-instance subfolder
    /// when an id is claimed.</summary>
    public static string DataRoot => Id is { } id
        ? Path.Combine(DefaultRoot, "instances", id)
        : DefaultRoot;
    /// <summary>Chromium's user data folder, or null to let WebView2 pick its default
    /// (which is what Release always does). Must be per-instance or the second
    /// instance dies on Chromium's exclusive lock.</summary>
    public static string? WebViewDataFolder => Id is null ? null : Path.Combine(DataRoot, "webview2");
    /// <summary>Reject anything that is not a plain path segment, so the variable can
    /// never be used to walk out of the profile directory or name a UNC path.</summary>
    private static string? Sanitize(string? raw)
    {
        if (string.IsNullOrWhiteSpace(raw)) return null;
        var trimmed = raw.Trim();
        foreach (var c in trimmed)
            if (!char.IsLetterOrDigit(c) && c != '-' && c != '_') return null;
        return trimmed;
    }
 #else
    // Release: one profile, no alternate paths, no environment variable. Multi-instance
    // is a development affordance, not a shipping feature.
    public static string DataRoot => DefaultRoot;
    public static string? WebViewDataFolder => null;
 #endif
    /// <summary>The one real user profile: <c>%APPDATA%\ytLlive</c>. Note the historical
    /// double-L — do not "fix" it, users already have their layouts there.</summary>
    public static string DefaultRoot => Path.Combine(
        Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData),
        "ytLlive");
 }
@@ -0,0 +1,204 @@
 using System;
 using System.Threading;
 namespace ytLive.Helpers;
 /// <summary>
 /// A fixed pool of four DEDICATED background threads at <see cref="ThreadPriority.BelowNormal"/>
 /// that split one composite into horizontal row strips. The compositor needs the split to get
 /// render inside a 16.67ms slot, but it must not compete with the encoder, the WGC capture
 /// callbacks, the WebView2 chat or the game the user is playing — hence the hard cap of four
 /// and the demotion.
 ///
 /// Research (2026-10-05, Unit 5): the demotion must NOT be done by poking
 /// <c>Thread.CurrentThread.Priority</c> inside <c>Parallel.For</c> — the pool is shared, so the
 /// demotion leaks into every unrelated work item that thread later runs
 /// (https://stackoverflow.com/questions/524483/net-backgroundworker-objects-thread-priority:
 /// "you have next to no control of which thread pool thread will actually run your task");
 /// https://stackoverflow.com/questions/1578599/c-sharp-lower-thread-priority-in-thread-pool:
 /// "You shouldn't mess with the priority of the regular ThreadPool, since you aren't the only
 /// consumer ... write your own producer/consumer queue, using your own Thread(s) as the
 /// consumer(s) — setting the thread priority yourself"). A real failed attempt confirmed it: a
 /// full test run after demoting the pool threads broke an unrelated audio-mix timing test.
 /// This class IS that producer/consumer queue; the caller thread is the producer and also runs
 /// one strip itself, so four workers never means five-way oversubscription.
 ///
 /// Contract: <see cref="For"/> blocks until every strip has run, each strip must write only its
 /// own rows (the compositor's blits already partition by row), and it must not be called from
 /// inside a strip (the blits never nest).
 /// </summary>
 internal static class StripPool
 {
    /// <summary>Four workers: the measured sweet spot on this box. Fewer leaves render over
    /// budget; more steals cycles from the game and the encoder and made render worse, not better.</summary>
    public const int Workers = 4;
    /// <summary>Below this many rows the fan-out costs more than it saves — run it inline.</summary>
    private const int MinRowsForFanOut = 64;
    private static readonly object[] _queueLocks = CreateLocks();
    private static readonly Queue<Strip>[] _queues = CreateQueues();
    private static readonly Queue<Strip>[] _free = CreateQueues();
    private static readonly SemaphoreSlim[] _signals = CreateSignals();
    private static Thread[]? _threads;
    private static int _roundRobin = -1;
    private sealed class Strip
    {
        public int From;
        public int To;              // exclusive
        public Action<int>? Body;
        public Batch? Owner;
    }
    private sealed class Batch
    {
        public int Remaining;
        public Exception? Error;
    }
    /// <summary>Run <paramref name="body"/> for every row in [from, to), split across the pool.</summary>
    public static void For(int from, int to, Action<int> body)
    {
        if (from >= to) return;
        var rows = to - from;
        if (rows < MinRowsForFanOut || !EnsureStarted())
        {
            for (var y = from; y < to; y++) body(y);
            return;
        }
        // Strips are handed to whole workers (not per-row tasks) so the strip boundaries —
        // and therefore the destination row each strip owns — are fixed before any of them run.
        var strips = Math.Min(Workers, rows);
        var chunk = (rows + strips - 1) / strips;
        var batch = new Batch { Remaining = strips - 1 }; // the caller runs the last one
        var first = from;
        for (var k = 0; k < strips - 1; k++)
        {
            var end = Math.Min(first + chunk, to);
            var w = NextWorker();
            var strip = Rent(w);
            strip.From = first;
            strip.To = end;
            strip.Body = body;
            strip.Owner = batch;
            lock (_queueLocks[w]) _queues[w].Enqueue(strip);
            _signals[w].Release();
            first = end;
        }
        try
        {
            for (var y = first; y < to; y++) body(y);
        }
        catch (Exception ex)
        {
            batch.Error ??= ex;
        }
        if (batch.Remaining > 0)
        {
            lock (batch)
            {
                while (batch.Remaining > 0) Monitor.Wait(batch);
            }
        }
        if (batch.Error != null) throw new InvalidOperationException("A compositor strip failed.", batch.Error);
    }
    private static void Worker(int index)
    {
        var signal = _signals[index];
        while (true)
        {
            signal.Wait();
            Strip? strip = null;
            lock (_queueLocks[index])
            {
                if (_queues[index].Count > 0) strip = _queues[index].Dequeue();
            }
            if (strip == null) continue; // released for an already-drained queue
            var batch = strip.Owner!;
            try
            {
                for (var y = strip.From; y < strip.To; y++) strip.Body!(y);
            }
            catch (Exception ex)
            {
                batch.Error ??= ex;
            }
            finally
            {
                strip.Body = null;
                strip.Owner = null;
                lock (_queueLocks[index]) _free[index].Enqueue(strip);
                lock (batch)
                {
                    if (--batch.Remaining == 0) Monitor.PulseAll(batch);
                }
            }
        }
    }
    private static Strip Rent(int worker)
    {
        lock (_queueLocks[worker])
            return _free[worker].Count > 0 ? _free[worker].Dequeue() : new Strip();
    }
    private static int NextWorker()
    {
        var w = Interlocked.Increment(ref _roundRobin) % Workers;
        return w < 0 ? w + Workers : w;
    }
    /// <summary>Start the workers on first use, so a WPF cold start pays nothing for them.</summary>
    private static bool EnsureStarted()
    {
        if (_threads != null) return true;
        lock (_signals)
        {
            if (_threads != null) return true;
            var threads = new Thread[Workers];
            for (var i = 0; i < Workers; i++)
            {
                var index = i; // capture per-iteration: the loop variable would be Workers by the time the thread runs
                var t = new Thread(() => Worker(index), 256 * 1024)
                {
                    IsBackground = true,
                    Name = $"compositor-strip-{i}",
                    Priority = ThreadPriority.BelowNormal,
                };
                threads[i] = t;
                t.Start();
            }
            _threads = threads;
            return true;
        }
    }
    private static object[] CreateLocks()
    {
        var l = new object[Workers];
        for (var i = 0; i < Workers; i++) l[i] = new object();
        return l;
    }
    private static Queue<Strip>[] CreateQueues()
    {
        var q = new Queue<Strip>[Workers];
        for (var i = 0; i < Workers; i++) q[i] = new Queue<Strip>();
        return q;
    }
    private static SemaphoreSlim[] CreateSignals()
    {
        var s = new SemaphoreSlim[Workers];
        for (var i = 0; i < Workers; i++) s[i] = new SemaphoreSlim(0, int.MaxValue);
        return s;
    }
 }
@@ -14,9 +14,7 @@ namespace ytLive.Helpers;
 public static class TokenStore
 {
    public static string DefaultPath => Path.Combine(
-        Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData),
+        InstanceProfile.DataRoot, "ytLlive.auth");
        "ytLlive",
        "ytLlive.auth");
    public static void Save(YouTubeChannel channel, string? path = null)
    {
@@ -14,6 +14,8 @@ Cross-cutting utilities. See [`schema.md`](../schema.md) for the memory-map conv
 | `InverseBoolToVisibilityConverter.cs` / `NotNullToVisibilityConverter.cs` | XAML value converters for visibility bindings |
 | `AllTrueToVisibilityConverter.cs` | Multi-value AND-gate → Visible; gates the layer-row capture menu items on row-IsBackground + staged-scene-is-Live (TASK 25) |
 | `CameraConflictProbe.cs` | Best-effort diagnostic: when a camera won't start, enumerates running processes known to hold cameras (OBS, Zoom, Teams, NVIDIA Broadcast, browsers, etc.) — Windows doesn't expose "which process has this device" via any public API, so this is a suspect list, not a verdict |
 | `StripPool.cs` | Four DEDICATED background threads at `BelowNormal` priority that split one composite into horizontal row strips (the caller runs a strip too); started lazily, runs inline below 64 rows. UNIT 5 — do NOT demote the ThreadPool from `Parallel.For`, it leaks into unrelated work (see ai.md "Render budget") |
 | `FrameCadence.cs` | Pure arrival-cadence counter (`FrameCadence` + `FrameCadenceSummary.Describe`): frames, gaps, hitches, longest/avg gap for a window of a timestamped stream. Fed by `MediaCaptureFrameSource` (camera stamps vs our arrivals) and `FramePump` (distinct webcam Epochs that reached the output) — UNIT 0, see ai.md "Frame cadence" |
 Related: [`Themes/Controls.xaml`](../Themes/Controls.xaml) styles the lists this
 class backs; [`Models/index.md`](../Models/index.md) and
@@ -1,19 +1,10 @@
 using System;
 using System.Collections;
 using System.ComponentModel;
 using System.IO;
 using System.Net.Http;
 using System.Windows;
 using System.Windows.Controls;
 using System.Windows.Input;
 using System.Windows.Media;
 using System.Windows.Media.Effects;
 using System.Windows.Threading;
 using System.Windows.Media.Animation;
 using System.Windows.Media.Imaging;
 using System.Windows.Shapes;
 using ytLive.Helpers;
 using ytLive.Models;
 using ytLive.ViewModels;
 namespace ytLive;
@@ -21,7 +12,9 @@ namespace ytLive;
 public partial class MainWindow : Window
 {
    private readonly MainViewModel _viewModel;
-    private readonly Dictionary<string, Storyboard> _activeBorderAnimations = new();
+    private Controls.TopBar _topBar = null!;
    private Controls.PreviewPane _previewPane = null!;
    private Controls.LeftPanel _leftPanel = null!;
    public MainWindow()
    {
@@ -29,13 +22,13 @@ public partial class MainWindow : Window
        InitializeComponent();
        AppLog.Write("MainWindow ctor: after InitializeComponent");
        _viewModel = (MainViewModel)DataContext;
        _viewModel.InitWebView2(WebViewHostPanel);
        _viewModel.PropertyChanged += OnViewModelPropertyChanged;
-        _viewModel.ChatMessages.CollectionChanged += OnChatMessagesChanged;
+        _topBar = (Controls.TopBar)FindName("TopBar")!;
        _previewPane = (Controls.PreviewPane)FindName("PreviewPane")!;
        _leftPanel = (Controls.LeftPanel)FindName("LeftPanel")!;
        UpdateTaskbarOverlay();
        UpdateSelectionOverlay();
-        AvatarImage.Source = null;
+        _topBar.RefreshAvatar();
        AvatarInitial.Visibility = Visibility.Collapsed;
        RestoreWindowGeometry();
        AppLog.Write("MainWindow ctor: end");
    }
@@ -43,33 +36,62 @@ public partial class MainWindow : Window
    private void MainWindow_Loaded(object sender, RoutedEventArgs e)
    {
        AppLog.Write("MainWindow loaded");
        // Web sources need the window HWND as the composition controller's parent,
        // which does not exist in the ctor — InitWebView2 runs here (Loaded), after
        // SourceInitialized. Nothing renders from web frames before this.
        _viewModel.InitWebView2();
    }
-    // ─── Window geometry persistence (launch size/position) ───
+    // ─── Window geometry (launch position/size) ───
-    // Saved on close (RestoreBounds so a maximized window remembers its
+    // Launch POSITION is derived, never restored: upper-left of the work area plus
-    // un-maximize rect); restored in the ctor before the window is shown.
+    // padding (creator ruling 2026-10-04). The old restore clamped the saved position
-    // Values clamp to the minimums and to the primary work area — a position
+    // to [work.Left - width + 120, work.Right - 120] horizontally and
-    // saved on a since-disconnected secondary monitor falls back on-screen.
+    // [work.Top, work.Bottom - 80] vertically — ranges wide enough to leave the window
    // almost entirely off-screen, which is what the creator was seeing ("below the
    // fold"). Size and maximized state are still persisted. Placement math is pure and
    // tested (WindowPlacementTests); changing it back to restore position is reverting
    // this block only, since the saved values are still written.
    /// <summary>Launch inset from the work-area corner, in device-independent units —
    /// so it scales with DPI rather than being a fixed physical pixel count.</summary>
    internal const double LaunchPadding = 75;
    /// <summary>Upper-left of <paramref name="workArea"/> plus padding, clamped so the
    /// window is never pushed off-screen. The clamp is the point: a window that fits
    /// stays wholly visible, and one too big to fit falls back to the work-area origin
    /// rather than hanging off an edge.</summary>
    internal static Point TopLeftPlacement(Rect workArea, double width, double height, double padding)
    {
        var left = workArea.Left + padding;
        var top = workArea.Top + padding;
        if (width <= workArea.Width) left = Math.Min(left, workArea.Right - width);
        else left = workArea.Left;
        if (height <= workArea.Height) top = Math.Min(top, workArea.Bottom - height);
        else top = workArea.Top;
        return new Point(left, top);
    }
    private void RestoreWindowGeometry()
    {
        try
        {
            var saved = _viewModel.RestoreWindowState();
            if (saved == null) return;
            var (left, top, width, height, state) = saved.Value;
            var work = SystemParameters.WorkArea;
-            width = Math.Clamp(width, MinWidth, work.Width);
+            var saved = _viewModel.RestoreWindowState();
            height = Math.Clamp(height, MinHeight, work.Height);
            left = Math.Clamp(left, work.Left - width + 120, work.Right - 120);
            top = Math.Clamp(top, work.Top, work.Bottom - 80);
-            Left = left;
+            // No saved state: keep the XAML-declared size rather than collapsing to Min*.
-            Top = top;
+            var width = Math.Clamp(saved?.Width ?? Width, MinWidth, work.Width);
            var height = Math.Clamp(saved?.Height ?? Height, MinHeight, work.Height);
            Width = width;
            Height = height;
-            if (state == "Maximized") WindowState = WindowState.Maximized;
+
            var place = TopLeftPlacement(work, width, height, LaunchPadding);
            Left = place.X;
            Top = place.Y;
            if (saved?.State == "Maximized") WindowState = WindowState.Maximized;
        }
        catch (Exception ex)
        {
@@ -116,7 +138,7 @@ public partial class MainWindow : Window
            UpdateSelectionOverlay();
        else if (e.PropertyName == nameof(MainViewModel.AccountAvatarUrl)
              || e.PropertyName == nameof(MainViewModel.IsConnected))
-            LoadAvatarImage();
+            _topBar.RefreshAvatar();
    }
    private void MainWindow_Closing(object? sender, CancelEventArgs e)
@@ -141,772 +163,32 @@ public partial class MainWindow : Window
            : null;
    }
    private static readonly HttpClient AvatarHttp = new() { Timeout = TimeSpan.FromSeconds(15) };
    private string? _loadedAvatarUrl;
    private async void LoadAvatarImage()
    {
        var url = _viewModel.AccountAvatarUrl;
        if (!_viewModel.IsConnected)
        {
            ShowAvatarFallback(null);
            return;
        }
        if (string.IsNullOrWhiteSpace(url))
        {
            AppLog.Write("Avatar: connected but no profile image URL on the session");
            ShowAvatarFallback(null);
            return;
        }
        if (url == _loadedAvatarUrl && AvatarImage.Source != null) return;
        try
        {
            var bytes = await AvatarHttp.GetByteArrayAsync(url);
            using var ms = new MemoryStream(bytes);
            var bitmap = new BitmapImage();
            bitmap.BeginInit();
            bitmap.CacheOption = BitmapCacheOption.OnLoad;
            bitmap.StreamSource = ms;
            bitmap.EndInit();
            bitmap.Freeze();
            _loadedAvatarUrl = url;
            AvatarImage.Source = bitmap;
            AvatarInitial.Visibility = Visibility.Collapsed;
        }
        catch (Exception ex)
        {
            AppLog.Write($"Avatar load failed ({url}): {ex.Message}");
            ShowAvatarFallback(_viewModel.AccountDisplayName);
        }
    }
    private void ShowAvatarFallback(string? name)
    {
        _loadedAvatarUrl = null;
        AvatarImage.Source = null;
        AvatarInitial.Text = string.IsNullOrWhiteSpace(name) ? "?" : name.Substring(0, 1).ToUpperInvariant();
        AvatarInitial.Visibility = Visibility.Visible;
    }
    private void SourceNameBox_IsVisibleChanged(object sender, DependencyPropertyChangedEventArgs e)
    {
        if (sender is TextBox { IsVisible: true } box)
        {
            box.Focus();
            box.SelectAll();
        }
    }
    private void VolumeSlider_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
    {
        if (sender is Slider slider)
            SetSliderValueFromClick(slider, e);
        if (sender is FrameworkElement { DataContext: MainViewModel vm })
            vm.SetVolumeAdjusting(true);
    }
    private void VolumeSlider_PreviewMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
    {
        if (sender is FrameworkElement { DataContext: MainViewModel vm })
            vm.SetVolumeAdjusting(false);
    }
    private void VolumeSlider_LostMouseCapture(object sender, MouseEventArgs e)
    {
        if (sender is FrameworkElement { DataContext: MainViewModel vm })
            vm.SetVolumeAdjusting(false);
    }
    private void GameVolumeSlider_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
    {
        if (sender is Slider slider)
            SetSliderValueFromClick(slider, e);
        if (sender is FrameworkElement { DataContext: MainViewModel vm })
            vm.SetGameVolumeAdjusting(true);
    }
    private void GameVolumeSlider_PreviewMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
    {
        if (sender is FrameworkElement { DataContext: MainViewModel vm })
            vm.SetGameVolumeAdjusting(false);
    }
    private void GameVolumeSlider_LostMouseCapture(object sender, MouseEventArgs e)
    {
        if (sender is FrameworkElement { DataContext: MainViewModel vm })
            vm.SetGameVolumeAdjusting(false);
    }
    private static void SetSliderValueFromClick(Slider slider, MouseButtonEventArgs e)
    {
        if (FindParent<System.Windows.Controls.Primitives.Thumb>(e.OriginalSource as Visual) != null)
            return;
        var track = slider.Template.FindName("PART_Track", slider) as System.Windows.Controls.Primitives.Track;
        if (track == null) return;
        var pos = e.GetPosition(track);
        var fraction = Math.Clamp(pos.X / track.RenderSize.Width, 0, 1);
        slider.Value = slider.Minimum + fraction * (slider.Maximum - slider.Minimum);
        e.Handled = true;
    }
    private static T? FindParent<T>(Visual? visual) where T : Visual
    {
        while (visual != null)
        {
            if (visual is T match) return match;
            visual = VisualTreeHelper.GetParent(visual) as Visual;
        }
        return null;
    }
    private void MicSpeaker_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
    {
        if (sender is FrameworkElement { DataContext: MainViewModel vm })
        {
            vm.ToggleMicMuteCommand.Execute(null);
        }
    }
    private void GameSpeaker_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
    {
        if (sender is FrameworkElement { DataContext: MainViewModel vm })
        {
            vm.ToggleGameMuteCommand.Execute(null);
        }
    }
    // TRAX (TASK 9): left-click toggles play/pause (picks a track when none is
    // loaded); right-click always opens the picker. The picker is the OS file
    // dialog — the "never the OS viewer" rule covers the preview, not pickers.
    private void TraxButton_Click(object sender, RoutedEventArgs e)
    {
        if (DataContext is ViewModels.MainViewModel vm)
            vm.TraxLeftClick();
    }
    private void TraxButton_PreviewMouseRightButtonUp(object sender, MouseButtonEventArgs e)
    {
        if (DataContext is ViewModels.MainViewModel vm)
            vm.TraxRightClick();
        e.Handled = true; // the button's right-click context menu must not fire
    }
    private void BackToAbout_Click(object sender, RoutedEventArgs e)
    {
        if (DataContext is ViewModels.MainViewModel vm)
        {
            vm.IsLicensesOpen = false;
            vm.IsLicenseEntryOpen = false;
        }
    }
    private void AddSourceButton_Click(object sender, RoutedEventArgs e)
    {
        if (sender is Button { ContextMenu: { } menu } button)
        {
            menu.PlacementTarget = button;
            menu.Placement = System.Windows.Controls.Primitives.PlacementMode.Bottom;
            menu.IsOpen = true;
        }
    }
    // ─── Preview image selection / move / resize ───
    private void Thumbnail_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
    {
        if (sender is Border { DataContext: Scene scene })
            _viewModel.TransitionToScene(scene);
    }
    private bool _isDraggingOverlay;
    private bool _isResizing;
    private Point _grabOffset;
    private double _resizeAspect;
    private void Window_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
    {
        if (e.OriginalSource is not DependencyObject original) return;
        var form = _viewModel.BroadcastForm;
-        if (form.IsDrawerOpen && !IsDescendantOf(original, TextPullOutHost))
+        var ypp = _viewModel.Ypp;
-            form.CloseDrawerCommand.Execute(null);
+        var test = _viewModel.TestSession;
-        if (IsDescendantOf(original, PreviewGrid)) return;
+        if (!_previewPane.IsClickInsideDrawer(original))
        if (IsDescendantOf(original, SourceList)) return;
        if (IsDescendantOf(original, ElementsScrollViewer)) return;
        _viewModel.SelectedElement = null;
    }
    private static bool IsDescendantOf(DependencyObject? child, DependencyObject ancestor)
    {
        while (child != null && !ReferenceEquals(child, ancestor))
        {
-            child = child is System.Windows.Media.Visual or System.Windows.Media.Media3D.Visual3D
+            if (form.IsDrawerOpen) form.CloseDrawerCommand.Execute(null);
-                ? VisualTreeHelper.GetParent(child)
+            if (ypp.IsDrawerOpen) ypp.CloseDrawerCommand.Execute(null);
-                : LogicalTreeHelper.GetParent(child);
+            if (test.IsDrawerOpen) test.CloseDrawerCommand.Execute(null);
        }
-        return child != null;
+        if (_previewPane.IsClickInsidePreview(original)) return;
        if (_leftPanel.IsClickInside(original)) return;
        _viewModel.SelectedElement = null;
    }
    private void UpdateSelectionOverlay()
    {
        if (!_viewModel.IsEditMode)
        {
-            SelectionOverlay.Visibility = Visibility.Collapsed;
+            _previewPane.UpdateSelectionOverlay(false);
            return;
        }
-        var selected = _viewModel.SelectedElement is { } s && IsDraggableElement(s);
+        var selected = _viewModel.SelectedElement is { } s && Controls.PreviewPane.IsDraggableElement(s);
-        SelectionOverlay.Visibility = selected ? Visibility.Visible : Visibility.Collapsed;
+        _previewPane.UpdateSelectionOverlay(selected);
-        if (selected)
+        _leftPanel.OnSelectionChanged(_viewModel);
            OpacityValueText.Text = $"{Math.Round(_viewModel.SelectedElement!.Opacity * 100)}%";
        TakeSnapshot();
    }
    private void OnChatMessagesChanged(object? sender, System.Collections.Specialized.NotifyCollectionChangedEventArgs e)
    {
        if (e.Action == System.Collections.Specialized.NotifyCollectionChangedAction.Add)
        {
            ChatListBox.ScrollIntoView(ChatListBox.Items[^1]);
        }
    }
    // Static images and the webcam share the move/resize/selection behavior.
    private static bool IsDraggableElement(SceneElement element)
        => element.IsDraggable;
    private void MirrorButton_Click(object sender, RoutedEventArgs e)
    {
        if (_viewModel.SelectedElement is WebcamSceneConfig webcam)
            webcam.IsMirrored = !webcam.IsMirrored;
    }
    private void ShapeButton_Click(object sender, RoutedEventArgs e)
    {
        if (_viewModel.SelectedElement is WebcamSceneConfig webcam)
            webcam.ToggleClipShape();
    }
    private void WebcamMenu_ChangeWebcam(object sender, RoutedEventArgs e)
        => _viewModel.ChangeWebcamCommand.Execute(null);
    private void WebcamMenu_SetBorderAnimation(object sender, RoutedEventArgs e)
    {
        if (sender is not MenuItem { DataContext: SceneElement element, Tag: string tag }
            || !Enum.TryParse<BorderAnimation>(tag, out var animation))
            return;
        element.BorderAnimation = animation;
        StopBorderAnimation(element.Id);
        if (animation == BorderAnimation.None) return;
        var shape = FindBorderShape(sender as DependencyObject);
        if (shape == null) return;
        var sb = CreateBorderAnimation(animation, shape);
        if (sb == null) return;
        sb.Freeze();
        _activeBorderAnimations[element.Id] = sb;
        shape.BeginAnimation(Shape.OpacityProperty, null);
        Storyboard.SetTarget(sb, shape);
        sb.Begin();
    }
    private void StopBorderAnimation(string elementId)
    {
        if (_activeBorderAnimations.TryGetValue(elementId, out var old))
        {
            old.Stop();
            _activeBorderAnimations.Remove(elementId);
        }
    }
    private static Shape? FindBorderShape(DependencyObject? start)
    {
        var current = start;
        while (current != null)
        {
            if (current is ContextMenu cm && cm.PlacementTarget is FrameworkElement target)
            {
                for (var i = 0; i < VisualTreeHelper.GetChildrenCount(target); i++)
                {
                    var child = VisualTreeHelper.GetChild(target, i);
                    if (child is Shape s && (s is Rectangle or Ellipse) && !s.IsHitTestVisible)
                        return s;
                }
                return null;
            }
            current = VisualTreeHelper.GetParent(current);
        }
        return null;
    }
    private static Storyboard? CreateBorderAnimation(BorderAnimation animation, Shape shape)
    {
        var sb = new Storyboard();
        switch (animation)
        {
            case BorderAnimation.Pulse:
                AddDoubleAnimation(sb, Shape.OpacityProperty, 1.0, 0.3, TimeSpan.FromSeconds(0.8), true);
                break;
            case BorderAnimation.Glow:
                AddDoubleAnimation(sb, Shape.OpacityProperty, 1.0, 0.5, TimeSpan.FromSeconds(1.2), true);
                break;
            case BorderAnimation.Shimmer:
                AddDoubleAnimation(sb, Shape.OpacityProperty, 1.0, 0.15, TimeSpan.FromSeconds(0.5), true);
                break;
            case BorderAnimation.Electricity:
                AddDoubleAnimation(sb, Shape.OpacityProperty, 1.0, 0.2, TimeSpan.FromSeconds(0.1), true);
                break;
            case BorderAnimation.Sparkles:
                AddDoubleAnimation(sb, Shape.OpacityProperty, 1.0, 0.4, TimeSpan.FromSeconds(0.3), true);
                break;
            case BorderAnimation.MarchingAnts:
                shape.StrokeDashArray = new DoubleCollection { 4, 2 };
                AddDoubleAnimation(sb, Shape.StrokeDashOffsetProperty, 0, -20, TimeSpan.FromSeconds(0.8), false);
                break;
            case BorderAnimation.Chase:
                shape.StrokeDashArray = new DoubleCollection { 8, 4 };
                AddDoubleAnimation(sb, Shape.StrokeDashOffsetProperty, 0, -30, TimeSpan.FromSeconds(1.5), false);
                break;
            case BorderAnimation.Rainbow:
                if (shape.Stroke is SolidColorBrush brush)
                {
                    var frozen = brush.IsFrozen;
                    if (frozen) brush = brush.Clone();
                    shape.Stroke = brush;
                    var colorAnim = new ColorAnimationUsingKeyFrames
                    {
                        Duration = new Duration(TimeSpan.FromSeconds(3)),
                        RepeatBehavior = RepeatBehavior.Forever
                    };
                    colorAnim.KeyFrames.Add(new LinearColorKeyFrame(Colors.Red, KeyTime.FromTimeSpan(TimeSpan.Zero)));
                    colorAnim.KeyFrames.Add(new LinearColorKeyFrame(Colors.Yellow, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(0.5))));
                    colorAnim.KeyFrames.Add(new LinearColorKeyFrame(Colors.Green, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(1))));
                    colorAnim.KeyFrames.Add(new LinearColorKeyFrame(Colors.DodgerBlue, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(1.5))));
                    colorAnim.KeyFrames.Add(new LinearColorKeyFrame(Colors.MediumPurple, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(2))));
                    colorAnim.KeyFrames.Add(new LinearColorKeyFrame(Colors.Red, KeyTime.FromTimeSpan(TimeSpan.FromSeconds(2.5))));
                    Storyboard.SetTargetProperty(colorAnim, new PropertyPath("(Shape.Stroke).(SolidColorBrush.Color)"));
                    sb.Children.Add(colorAnim);
                }
                break;
            default:
                return null;
        }
        return sb.Children.Count > 0 ? sb : null;
    }
    private static void AddDoubleAnimation(Storyboard sb, DependencyProperty prop,
        double from, double to, Duration duration, bool autoReverse)
    {
        var anim = new DoubleAnimation(from, to, duration)
        {
            AutoReverse = autoReverse,
            RepeatBehavior = RepeatBehavior.Forever
        };
        Storyboard.SetTargetProperty(anim, new PropertyPath(prop));
        sb.Children.Add(anim);
    }
    private void WebcamMenu_SetBorderColor(object sender, RoutedEventArgs e)
    {
        if (sender is MenuItem { DataContext: SceneElement element, Tag: string color })
            element.BorderColor = color;
    }
    private void WebcamMenu_HideInScene(object sender, RoutedEventArgs e)
    {
        if (sender is MenuItem { DataContext: SceneElement element })
            element.IsVisible = false;
    }
    private void WebcamMenu_Remove(object sender, RoutedEventArgs e)
    {
        if (sender is MenuItem { DataContext: SceneElement element })
            _viewModel.RemoveSourceCommand.Execute(element);
    }
    private void BackgroundMenu_ChangeCapture(object sender, RoutedEventArgs e)
    {
        _ = _viewModel.ChangeBackgroundCaptureAsync();
    }
    private void BackgroundMenu_RefreshCapture(object sender, RoutedEventArgs e)
    {
        _viewModel.RefreshBackgroundAutoCapture();
    }
    private void SourceMenu_Remove(object sender, RoutedEventArgs e)
    {
        if (sender is MenuItem { DataContext: SceneElement element })
            _viewModel.RemoveSourceCommand.Execute(element);
    }
    private void OpacitySlider_ValueChanged(object sender, RoutedPropertyChangedEventArgs<double> e)
        => OpacityValueText.Text = $"{Math.Round(e.NewValue * 100)}%";
    // ─── Social bar: click toggles top ⇄ bottom. KISS — the drag variant was
    // unusable for shaky hands (jitter around the direction deadzone), so the bar
    // rides on {Binding SocialBarTop} alone and a click flips it. ───
    private void SocialBar_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
    {
        _viewModel.ToggleSocialBarPosition();
        e.Handled = true;
    }
    private DispatcherTimer? _socialGlowTimer;
    private double _socialGlowAngle;
    private void SocialsButton_MouseEnter(object sender, MouseEventArgs e)
    {
        if (SocialBarElement == null) return;
        // Kick the social bar to full brightness so it's immediately visible
        var effect = SocialBarElement.Effect as DropShadowEffect;
        if (effect != null)
        {
            effect.BlurRadius = 40;
            effect.Opacity = 1.0;
        }
        // Pulse the glow so it catches the eye
        _socialGlowAngle = 0;
        _socialGlowTimer?.Stop();
        _socialGlowTimer = new DispatcherTimer { Interval = TimeSpan.FromMilliseconds(30) };
        _socialGlowTimer.Tick += SocialGlowTick;
        _socialGlowTimer.Start();
    }
    private void SocialsButton_MouseLeave(object sender, MouseEventArgs e)
    {
        _socialGlowTimer?.Stop();
        _socialGlowTimer = null;
        if (SocialBarElement?.Effect is DropShadowEffect effect)
        {
            effect.BlurRadius = 18;
            effect.Opacity = 0.9;
        }
    }
    private void SocialGlowTick(object? sender, EventArgs e)
    {
        if (SocialBarElement?.Effect is not DropShadowEffect effect) return;
        _socialGlowAngle += 0.18;
        if (_socialGlowAngle > Math.PI * 2) _socialGlowAngle -= Math.PI * 2;
        // Smooth sine pulse: BlurRadius 24→48, Opacity 0.7→1.0
        double t = (Math.Sin(_socialGlowAngle) + 1.0) / 2.0; // 0..1
        effect.BlurRadius = 24 + t * 24;
        effect.Opacity = 0.7 + t * 0.3;
    }
    private void Preview_MouseLeftButtonDown(object sender, MouseButtonEventArgs e)
    {
        if (!_viewModel.IsEditMode) return;
        var grid = (Grid)sender;
        var toCanvas = CanvasGrid.TransformToVisual(grid).Inverse;
        var p = toCanvas.Transform(e.GetPosition(grid));
        var selected = _viewModel.SelectedElement;
        if (selected is { } sel && IsDraggableElement(sel) && HitHandle(e.GetPosition(grid), sel))
        {
            _isResizing = true;
            _resizeAspect = sel.ClipShape == ClipShape.Round ? 1 : sel.Width / Math.Max(1, sel.Height);
            grid.CaptureMouse();
            e.Handled = true;
            return;
        }
        var hit = HitElement(p);
        if (hit != null)
        {
            _viewModel.SelectedElement = hit;
            _isDraggingOverlay = true;
            _grabOffset = new Point(p.X - hit.X, p.Y - hit.Y);
            grid.CaptureMouse();
            e.Handled = true;
            return;
        }
        _viewModel.SelectedElement = null;
    }
    private void Preview_MouseMove(object sender, MouseEventArgs e)
    {
        if (!_viewModel.IsEditMode) return;
        if (!_isDraggingOverlay && !_isResizing) return;
        var grid = (Grid)sender;
        var toCanvas = CanvasGrid.TransformToVisual(grid).Inverse;
        var p = toCanvas.Transform(e.GetPosition(grid));
        var selected = _viewModel.SelectedElement;
        if (selected == null)
        {
            EndPreviewDrag(grid);
            return;
        }
        if (_isDraggingOverlay)
        {
            var minX = -(selected.Width - 20);
            var maxX = 1920 - 20;
            var minY = -(selected.Height - 20);
            var maxY = 1080 - 20;
            selected.X = Math.Clamp(p.X - _grabOffset.X, Math.Min(minX, maxX), Math.Max(minX, maxX));
            selected.Y = Math.Clamp(p.Y - _grabOffset.Y, Math.Min(minY, maxY), Math.Max(minY, maxY));
        }
        else if (_isResizing)
        {
            var isWebcam = selected is WebcamSceneConfig;
            var isRound = selected.ClipShape == ClipShape.Round;
            var proportional = isRound || Keyboard.Modifiers.HasFlag(ModifierKeys.Shift);
            var maxW = isWebcam ? MainViewModel.MaxWebcamWidthFor(_viewModel.StagedScene?.Name) : 1920;
            var maxH = isWebcam ? MainViewModel.MaxWebcamHeightFor(_viewModel.StagedScene?.Name) : 1080;
            var newW = Math.Clamp(p.X - selected.X, 32, maxW);
            var newH = proportional ? newW / _resizeAspect : Math.Clamp(p.Y - selected.Y, 32, maxH);
            if (proportional && newH > maxH)
            {
                newH = maxH;
                newW = newH * _resizeAspect;
            }
            selected.Width = newW;
            selected.Height = newH;
        }
    }
    private void Preview_MouseLeftButtonUp(object sender, MouseButtonEventArgs e)
        => EndPreviewDrag((Grid)sender);
    private void EndPreviewDrag(Grid grid)
    {
        if (_isDraggingOverlay || _isResizing)
            grid.ReleaseMouseCapture();
        _isDraggingOverlay = false;
        _isResizing = false;
    }
    private bool HitHandle(Point mouseScreen, SceneElement element)
    {
        var corner = CanvasGrid.TransformToVisual(PreviewGrid).Transform(new Point(element.X + element.Width, element.Y + element.Height));
        return Math.Abs(mouseScreen.X - corner.X) <= 20 && Math.Abs(mouseScreen.Y - corner.Y) <= 20;
    }
    private SceneElement? HitElement(Point p)
    {
        var scene = _viewModel.StagedScene;
        if (scene == null) return null;
        for (var i = scene.Elements.Count - 1; i >= 0; i--)
        {
            var element = scene.Elements[i];
            if (!IsDraggableElement(element)) continue;
            if (element is Source { IsEnabled: false }) continue;
            if (element is WebcamSceneConfig { IsVisible: false }) continue;
            if (p.X >= element.X && p.X <= element.X + element.Width &&
                p.Y >= element.Y && p.Y <= element.Y + element.Height)
                return element;
        }
        return null;
    }
    private void SourceNameBox_KeyDown(object sender, KeyEventArgs e)
    {
        if (e.Key is Key.Enter or Key.Escape)
        {
            CommitSourceEdit(sender);
            e.Handled = true;
        }
    }
    private void SourceNameBox_LostFocus(object sender, RoutedEventArgs e)
    {
        CommitSourceEdit(sender);
    }
    private static void CommitSourceEdit(object sender)
    {
        if (sender is FrameworkElement { DataContext: SceneElement element })
            element.IsEditing = false;
    }
    // ─── List drag-to-reorder (scenes list + sources list) ───
    private Point _dragStartPoint;
    private int _dragIndex = -1;
    private bool _isDragging;
    private object? _lastHoveredItem;
    private void List_PreviewMouseLeftButtonDown(object sender, MouseButtonEventArgs e)
    {
        var listBox = (ListBox)sender;
        var item = FindItemContainerAt(listBox, e.GetPosition(listBox));
        if (item == null)
        {
            if (ReferenceEquals(listBox, SourceList))
                _viewModel.SelectedElement = null;
            _dragIndex = -1;
            return;
        }
        if (listBox.ItemsSource is not IList items || items.Count == 0)
        {
            _dragIndex = -1;
            return;
        }
        _dragIndex = listBox.Items.IndexOf(item.DataContext);
        _dragStartPoint = e.GetPosition(listBox);
        _isDragging = false;
        _lastHoveredItem = null;
    }
    private void List_PreviewMouseMove(object sender, MouseEventArgs e)
    {
        if (_dragIndex < 0) return;
        var listBox = (ListBox)sender;
        if (e.LeftButton != MouseButtonState.Pressed || listBox.ItemsSource is not IList items)
        {
            EndListDrag(listBox);
            return;
        }
        var position = e.GetPosition(listBox);
        if (!_isDragging)
        {
            if (Math.Abs(position.X - _dragStartPoint.X) < SystemParameters.MinimumHorizontalDragDistance &&
                Math.Abs(position.Y - _dragStartPoint.Y) < SystemParameters.MinimumVerticalDragDistance)
                return;
            _isDragging = true;
            listBox.CaptureMouse();
        }
        var item = FindItemContainerAt(listBox, position);
        if (item == null) return;
        var targetItem = item.DataContext;
        if (ReferenceEquals(targetItem, items[_dragIndex]) || ReferenceEquals(targetItem, _lastHoveredItem))
            return;
        var targetIndex = listBox.Items.IndexOf(targetItem);
        if (targetIndex < 0) return;
        var dragged = items[_dragIndex];
        items.RemoveAt(_dragIndex);
        items.Insert(targetIndex, dragged);
        _dragIndex = targetIndex;
        _lastHoveredItem = targetItem;
    }
    private void List_PreviewMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
    {
        EndListDrag((ListBox)sender);
    }
    private void EndListDrag(ListBox listBox)
    {
        if (_isDragging)
            listBox.ReleaseMouseCapture();
        _dragIndex = -1;
        _isDragging = false;
        _lastHoveredItem = null;
    }
    private static ListBoxItem? FindItemContainerAt(ListBox listBox, Point position)
    {
        var hit = listBox.InputHitTest(position) as DependencyObject;
        while (hit != null && hit != listBox)
        {
            if (hit is ListBoxItem item) return item;
            hit = VisualTreeHelper.GetParent(hit);
        }
        return null;
    }
    private Models.SceneElement? _snapshotElement;
    private string _snapshotBorderColor = string.Empty;
    private int _snapshotBorderWidth;
    private int _snapshotTimerMinutes = 15;
    private string? _snapshotWebUri;
    private void TakeSnapshot()
    {
        if (_viewModel.SelectedElement is Models.Source src)
        {
            _snapshotElement = src;
            _snapshotBorderColor = src.BorderColor;
            _snapshotBorderWidth = src.BorderWidth;
            _snapshotTimerMinutes = src.TimerMinutes;
            _snapshotWebUri = src.WebUri;
        }
    }
    private void WebcamBorderColorPicker_Click(object sender, RoutedEventArgs e)
    {
        if (_viewModel.SelectedElement is not SceneElement src) return;
        if (sender is FrameworkElement fe && fe.ContextMenu == null)
        {
            var menu = new System.Windows.Controls.ContextMenu();
            string[] colors = ["#FFFFFF", "#000000", "#FF0000", "#00FF00", "#0000FF",
                               "#FFFF00", "#FF00FF", "#00FFFF", "#FF8800", "#8800FF",
                               "#e94560", "#22c55e", "#3b82f6", "#f59e0b"];
            foreach (var c in colors)
            {
                var item = new System.Windows.Controls.MenuItem { Header = c, ToolTip = c };
                var brush = new System.Windows.Media.SolidColorBrush(
                    (System.Windows.Media.Color)System.Windows.Media.ColorConverter.ConvertFromString(c));
                item.Icon = new System.Windows.Controls.Border
                {
                    Width = 16, Height = 16,
                    Background = brush,
                    CornerRadius = new System.Windows.CornerRadius(2)
                };
                var color = c;
                item.Click += (_, _) => src.BorderColor = color;
                menu.Items.Add(item);
            }
            fe.ContextMenu = menu;
        }
        if (sender is FrameworkElement fe2)
            fe2.ContextMenu.IsOpen = true;
    }
    private void WebcamBorderRevert_Click(object sender, RoutedEventArgs e)
    {
        if (_snapshotElement is Models.Source src)
        {
            src.BorderColor = _snapshotBorderColor;
            src.BorderWidth = _snapshotBorderWidth;
        }
    }
    private void WebcamBorderAccept_Click(object sender, RoutedEventArgs e)
    {
        if (_snapshotElement is Models.Source src)
        {
            _snapshotBorderColor = src.BorderColor;
            _snapshotBorderWidth = src.BorderWidth;
        }
    }
    private void CountdownRevert_Click(object sender, RoutedEventArgs e)
    {
        if (_snapshotElement is Models.Source src)
            src.TimerMinutes = _snapshotTimerMinutes;
    }
    private void CountdownAccept_Click(object sender, RoutedEventArgs e)
    {
        if (_snapshotElement is Models.Source src)
            _snapshotTimerMinutes = src.TimerMinutes;
    }
    private void WebRevert_Click(object sender, RoutedEventArgs e)
    {
        if (_snapshotElement is Models.Source src)
            src.WebUri = string.Empty;
        _snapshotWebUri = string.Empty;
    }
    private void WebAccept_Click(object sender, RoutedEventArgs e)
    {
        if (_snapshotElement is Models.Source src)
            _snapshotWebUri = src.WebUri;
    }
 }
@@ -19,6 +19,17 @@ public enum BorderAnimation
    Sparkles
 }
 /// <summary>Whether an element's pixel content is fixed (bake once into the
 /// compositor's cached base) or changes every frame (composite each tick).
 /// See ai.md "SceneGraph component + baked-crust compositor" (TASK 31).</summary>
 public enum ElementKind
 {
    /// <summary>Pixels never change at runtime (images, background art).</summary>
    Static,
    /// <summary>Pixels change every frame (webcam, live capture, chat, web source).</summary>
    Dynamic
 }
 /// <summary>
 /// A thing rendered in a scene: a multi-instance Source (image/background/text)
 /// or a singleton resource's per-scene config (webcam). Carries the shared
@@ -44,6 +55,15 @@ public abstract class SceneElement : INotifyPropertyChanged
    private string _name = string.Empty;
    public string Name { get => _name; set => Set(ref _name, value); }
    /// <summary>Whether this element's pixels are fixed (Static) or change every
    /// frame (Dynamic). The compositor bakes all Static layers below the first
    /// Dynamic layer once (see <c>SceneGraph.GetSplitPoint</c>).</summary>
    public virtual ElementKind Kind => ElementKind.Static;
    /// <summary>True only for the transient zoom layer. Gates zoom-only UI:
    /// hidden from the layers list, never selectable/draggable in the preview.</summary>
    public virtual bool IsZoomLayer => false;
    /// <summary>True only for singleton resources (webcam). Gates webcam-only UI.</summary>
    public virtual bool IsWebcam => false;
@@ -61,6 +81,9 @@ public abstract class SceneElement : INotifyPropertyChanged
    /// <summary>True only for Countdown-type sources. Gates timer properties panel.</summary>
    public virtual bool IsCountdown => false;
    /// <summary>True only for AlertBox-type sources. Gates stream alerts properties panel.</summary>
    public virtual bool IsAlertBox => false;
    public virtual bool IsBackground { get; set; }
    private bool _useDefaultBackground = true;
@@ -13,7 +13,10 @@ public enum SourceType
    Countdown,
    WebSource,
    ChatBox,
-    MediaSource
+    MediaSource,
    /// <summary>The designated alert zone: the six monetization events play their
    /// unique celebration animations here (OBS alert-box equivalent, native).</summary>
    AlertBox
 }
 /// <summary>Distinguishes how a media source presents its content (TASK 21).</summary>
@@ -37,6 +40,19 @@ public enum ClipShape
    Round
 }
 /// <summary>How an alert box presents its announcement strip (TASK 47). The strip is
 /// the full-width pill naming the event ("Viewer — Super Chat · $12.34").</summary>
 public enum AlertDisplayMethod
 {
    /// <summary>Marquee: the pill scrolls across the top edge, paced so the text is
    /// read <see cref="AlertOverlayLayer.TickerReadsPerAlert"/> times per alert.</summary>
    TickerScroll,
    /// <summary>Pulse: the static pill blinks on and off for the whole alert.</summary>
    Flash,
    /// <summary>Static: the pill sits centred and still for the whole alert.</summary>
    Solid
 }
 /// <summary>
 /// A multi-instance scene object: image/background/text (screen/window later).
 /// The webcam is NOT a Source — it's a singleton resource whose per-scene usage
@@ -61,7 +77,12 @@ public class Source : SceneElement
        }
    }
-    public override bool IsDraggable => Type is SourceType.Image or SourceType.WebSource or SourceType.ChatBox;
+    public override bool IsDraggable => Type is SourceType.Image or SourceType.WebSource or SourceType.ChatBox or SourceType.AlertBox;
    /// <summary>Live captures, chat, web sources and media are dynamic; static art is fixed.</summary>
    public override ElementKind Kind => Type is SourceType.DisplayCapture or SourceType.WindowCapture
        or SourceType.ChatBox or SourceType.WebSource or SourceType.MediaSource or SourceType.AlertBox
        ? ElementKind.Dynamic : ElementKind.Static;
    public override bool IsWebSource => Type == SourceType.WebSource;
@@ -113,7 +134,7 @@ public class Source : SceneElement
    public override ImageSource? DisplaySource => IsLiveCapture
        ? (VideoImageSource ?? _imageSource)
-        : (Type is SourceType.ChatBox or SourceType.WebSource ? VideoImageSource : _imageSource);
+        : (Type is SourceType.ChatBox or SourceType.WebSource or SourceType.MediaSource or SourceType.AlertBox ? VideoImageSource : _imageSource);
    public override bool IsImageSource => Type == SourceType.Image;
@@ -171,6 +192,54 @@ public class Source : SceneElement
    public bool IsMediaSource => Type == SourceType.MediaSource;
    // Alert video config (TASK 47): the shipped default clip lives in the Asset
    // table (seeded like image assets); the creator's replacement is a FILE PATH
    // reference only — never into the DB (creator ruling, 2026-09-26). Runtime
    // order: replacement path exists → DB default → six celebration animations.
    private string? _alertVideoAssetId;
    public string? AlertVideoAssetId
    {
        get => _alertVideoAssetId;
        set => Set(ref _alertVideoAssetId, value);
    }
    private string? _alertVideoPath;
    public string? AlertVideoPath
    {
        get => _alertVideoPath;
        set => Set(ref _alertVideoPath, value);
    }
    private bool _alertUseDefaultVideo = true;
    public bool AlertUseDefaultVideo
    {
        get => _alertUseDefaultVideo;
        set => Set(ref _alertUseDefaultVideo, value);
    }
    private bool _alertShowTicker = true;
    public bool AlertShowTicker
    {
        get => _alertShowTicker;
        set => Set(ref _alertShowTicker, value);
    }
    private double _alertVideoVolume = 1.0;
    public double AlertVideoVolume
    {
        get => _alertVideoVolume;
        set => Set(ref _alertVideoVolume, Math.Clamp(value, 0.0, 1.0));
    }
    private AlertDisplayMethod _alertDisplayMethod = AlertDisplayMethod.TickerScroll;
    public AlertDisplayMethod AlertDisplayMethod
    {
        get => _alertDisplayMethod;
        set => Set(ref _alertDisplayMethod, value);
    }
    public override bool IsAlertBox => Type == SourceType.AlertBox;
    // Chat box config (TASK 3.18)
    private double _chatFontSize = 16;
    public double ChatFontSize
@@ -13,5 +13,6 @@ public class WebcamSceneConfig : SceneElement
    public string WebcamId { get; init; } = string.Empty;
    public override bool IsWebcam => true;
    public override bool IsDraggable => true;
    public override ElementKind Kind => ElementKind.Dynamic;
    public override ImageSource? DisplaySource => VideoImageSource;
 }
@@ -0,0 +1,27 @@
 namespace ytLive.Models;
 /// <summary>One user-visible open window offered by the "Capture Window…"
 /// submenu. Carries its owning process name for disambiguation and the raw
 /// HWND that becomes the "window:&lt;hwnd&gt;" capture key.</summary>
 public sealed class WindowInfo
 {
    public WindowInfo(string title, string processName, long hwnd, int processId)
    {
        Title = title;
        ProcessName = processName;
        Hwnd = hwnd;
        ProcessId = processId;
    }
    public string Title { get; }
    public string ProcessName { get; }
    public long Hwnd { get; }
    public int ProcessId { get; }
    /// <summary>Menu label: "Title — ProcessName" (e.g. "bash — WindowsTerminal").</summary>
    public string Label => $"{Title} — {ProcessName}";
    /// <summary>The capture key fed to the screen-capture factory
    /// ("window:&lt;hwnd&gt;").</summary>
    public string CaptureKey => $"window:0x{Hwnd:X}";
 }
@@ -18,6 +18,21 @@ public record ReusableStream(string Id, string IngestionAddress, string StreamNa
    public string RtmpUrl => $"{IngestionAddress}/{StreamName}";
 }
 /// <summary>The six monetization events YouTube's live chat feed emits (the ONLY
 /// native event stream there is — free subscribers produce no event). Each kind
 /// drives its own celebration animation in the AlertBox. <c>None</c> = a normal
 /// chat row: it never enqueues an alert (subscriber mentions stay chat rows).</summary>
 public enum ChatEventKind
 {
    None,
    SuperChat,
    SuperSticker,
    NewMember,
    MemberGift,
    GiftReceived,
    MemberMilestone,
 }
 public class ChatMessage
 {
    public string Id { get; init; } = Guid.NewGuid().ToString();
@@ -29,6 +44,30 @@ public class ChatMessage
    public bool IsSuperChat { get; set; }
    public double SuperChatAmount { get; set; }
    public string? SuperChatCurrency { get; set; }
    /// <summary>YouTube's own pre-rendered amount ("$12.34") — preferred over
    /// recomposing amount+currency ourselves, which mangles non-dollar locales.</summary>
    public string? SuperChatDisplayString { get; set; }
    public bool IsMember { get; set; }
    public string? MembershipLevel { get; set; }
    public ChatEventKind Kind { get; set; }
    public string? SuperStickerDescription { get; set; }
    /// <summary>membershipGiftingEvent: how many memberships were bought.</summary>
    public int GiftNewMembersCount { get; set; }
    /// <summary>giftMembershipReceivedEvent: who gifted this one.</summary>
    public string? GifterName { get; set; }
    /// <summary>memberMilestoneChatEvent: streak months (0 = YouTube didn't
    /// expose a count — the animation falls back to the message text).</summary>
    public int MilestoneMonths { get; set; }
    /// <summary>TASK 41: the Test Stream dock injects synthetic member / SuperChat /
    /// subscriber events locally (YouTube's insert API only supports text), so the
    /// buffer can label them honestly — simulated events never reach YouTube.</summary>
    public bool IsSimulated { get; set; }
 }
@@ -0,0 +1,17 @@
 namespace ytLive.Models;
 /// <summary>One captured snapshot of a connected channel's YPP-relevant numbers
 /// (TASK 39). Appended on every refresh and archived in SQLite so a later slice
 /// can compute velocity/(de)acceleration/ETA from the history.</summary>
 public sealed class YppStatSnapshot
 {
    public DateTime CapturedAtUtc { get; set; }
    public long SubscriberCount { get; set; }
    public long VideoCount { get; set; }
    public long TotalViews { get; set; }
    public int UploadsLast90Days { get; set; }
    public bool CommunityGuidelinesGoodStanding { get; set; }
    public bool CopyrightStrikesGoodStanding { get; set; }
    public bool ContentIdClaimsGoodStanding { get; set; }
    public bool OverallGoodStanding { get; set; }
 }
@@ -0,0 +1,31 @@
 namespace ytLive.Models;
 /// <summary>YPP eligibility thresholds as versioned, date-aware DATA — never
 /// constants (ai.md "Journey tracker"). Tier 1 (fan funding) is time-invariant;
 /// Tier 2 (ad revenue) doubles its long-form-hours and Shorts-view bars for NEW
 /// applicants after 2027-02-01. Hardcoding the pre-2027 numbers would show the
 /// wrong ETA once the doubling lands, so callers resolve the active Tier 2
 /// threshold through <see cref="Tier2For"/>.</summary>
 public static class YppThresholds
 {
    public sealed record TierThreshold(string Name, long Subscribers, long WatchHours, long ShortsViews);
    /// <summary>The date the Tier-2 ad-revenue bars double for new applicants.</summary>
    public static readonly DateTime Tier2DoublingDate = new(2027, 2, 1);
    /// <summary>Fan-funding tier (before the full ad/YouTube Premium revenue tier).</summary>
    public static TierThreshold Tier1 { get; } = new("Fan funding", 500, 3_000, 3_000_000);
    /// <summary>The Tier-2 bar for a given point in time — 4,000h / 10M Shorts
    /// before the doubling date, 8,000h / 20M Shorts on or after it.</summary>
    public static TierThreshold Tier2For(DateTime when) => when >= Tier2DoublingDate
        ? new TierThreshold("Ad revenue", 1_000, 8_000, 20_000_000)
        : new TierThreshold("Ad revenue", 1_000, 4_000, 10_000_000);
    /// <summary>The currently-active Tier-2 threshold (resolved against today).</summary>
    public static TierThreshold Tier2Now => Tier2For(DateTime.UtcNow);
    /// <summary>Valid public long-form uploads required in the trailing 90 days
    /// to keep each tier route eligible.</summary>
    public const int UploadsRequiredPer90Days = 3;
 }
@@ -0,0 +1,36 @@
 using System.Windows.Media;
 namespace ytLive.Models;
 /// <summary>
 /// The transient zoom layer. It is a real scene element, but a special one: while
 /// active the SceneCompositor draws it LAST (layer n+1, above everything) as a live
 /// 2x view of a FIXED capture window (the box/2 region centred on where the creator
 /// clicked), sampled from the just-composited frame — so it captures ALL layers and
 /// keeps showing the same content no matter where the box is dragged (creator ruling
 /// 2026-10-08). Its X/Y/W/H are the movable BOX placement; CaptureX/CaptureY is the
 /// anchored capture window. While inactive it is an invisible placeholder that is
 /// never persisted (LayoutStore hand-rolls only Source/WebcamSceneConfig rows) — the
 /// VM re-inserts it on load and on scene creation, mirroring how backgrounds heal.
 /// </summary>
 public sealed class ZoomSceneElement : SceneElement
 {
    /// <summary>True only while a zoom box is live; flips Kind so the layer leaves
    /// the baked static base and composites per-frame.</summary>
    public bool IsZoomActive { get; set; }
    /// <summary>Master-space top-left of the fixed capture window. Set once by
    /// <c>ActivateZoom</c>; moving the box must never touch it.</summary>
    public double CaptureX { get; set; }
    public double CaptureY { get; set; }
    public override ElementKind Kind => IsZoomActive ? ElementKind.Dynamic : ElementKind.Static;
    public override bool IsZoomLayer => true;
    public override bool IsDraggable => false;
    /// <summary>Never rendered by the element template or the resolver — the preview
    /// magnifier (ZoomBox) and the output compositor's zoom pass own its pixels.</summary>
    public override ImageSource? DisplaySource => null;
 }
@@ -0,0 +1,8 @@
 namespace ytLive.Models;
 public enum ZoomShape
 {
    Circle,
    VerticalRectangle,
    HorizontalRectangle
 }
@@ -0,0 +1,27 @@
 using System;
 namespace ytLive.Models;
 public class ZoomState
 {
    public bool IsActive { get; set; }
    public double X { get; set; }
    public double Y { get; set; }
    public double Width { get; set; }
    public double Height { get; set; }
    /// <summary>Master-space top-left of the FIXED capture window (the box/2 region
    /// centred on the click). The box can be dragged anywhere; this never changes —
    /// the box always shows this same region magnified 2x (creator ruling 2026-10-08).</summary>
    public double CaptureX { get; set; }
    public double CaptureY { get; set; }
    public bool IsMoving { get; set; }
    public double GrabOffsetX { get; set; }
    public double GrabOffsetY { get; set; }
    public double Left => X;
    public double Top => Y;
    public double Right => X + Width;
    public double Bottom => Y + Height;
 }
@@ -7,14 +7,15 @@ Plain data types. No logic beyond what a property can carry. See
 |------|---------|
 | `Scene.cs` | A scene: `Name`, `IsHidden`, `IsChatScene`, `IsEditing`, **`HasBackdrop`** (Live-only policy flag, default off — only the canonical Live scene has one, see `SceneCatalog`), `Elements` collection (images + webcam config), `WebcamConfig` accessor |
 | `SceneCatalog.cs` | The five canonical scenes (Starting/Live/BRB/Chat/Ending) — the product, by name: `All`, `IsCanonical`, `Is(name, canonical)` (case-insensitive trim), `IsChat`, `HasBackdrop(name)` (true only for Live). Drives the empty-DB seed, the "+" missing-scenes menu, and `MainViewModel.EnforceBackdropPolicy` |
-| `Source.cs` | A source: `SourceType` enum (DisplayCapture/WindowCapture/Background/Image/TextOverlay — **Webcam removed**), `X`/`Y`/`Width`/`Height`, `Opacity`, `IsEnabled`, `ImageSource` (static) / `VideoImageSource` (live frames), `DisplaySource` (`IsLiveCapture` → video, else static), `ClipShape` enum (Traditional/Round), `IsMirrored` + `MirrorScale`, `MirrorButtonText`/`ShapeButtonText`, asset identity, `IsImageSource` (XAML binds this, never `Type`), **backdrop surface**: `IsBackdrop` (permanent bottom layer, never removable), `CaptureKey` (persisted `monitor:<n>`/`window:<hwnd>`/`picker:<name>`), `IsLiveCapture` (`Type` is Display/WindowCapture) |
+| `Source.cs` | A source: `SourceType` enum (DisplayCapture/WindowCapture/Background/Image/TextOverlay/ChatBox/Countdown/WebSource/MediaSource/**AlertBox (TASK 43 — the celebration zone, one per layout)** — **Webcam removed**), `X`/`Y`/`Width`/`Height`, `Opacity`, `IsEnabled`, `ImageSource` (static) / `VideoImageSource` (live frames), `DisplaySource` (`IsLiveCapture` → video, else static), `ClipShape` enum (Traditional/Round), `IsMirrored` + `MirrorScale`, `MirrorButtonText`/`ShapeButtonText`, asset identity, `IsImageSource` (XAML binds this, never `Type`), **backdrop surface**: `IsBackdrop` (permanent bottom layer, never removable), `CaptureKey` (persisted `monitor:<n>`/`window:<hwnd>`/`picker:<name>`), `IsLiveCapture` (`Type` is Display/WindowCapture) |
-| `SceneElement.cs` | Base for anything placeable in a scene: shared layout/clip/mirror/border surface, `virtual IsWebcam`/`virtual IsImageSource`; `ToggleClipShape` + persisted `RectWidth`/`RectHeight` (pre-Round rect so round→rect restores after reload) |
+| `SceneElement.cs` | Base for anything placeable in a scene: shared layout/clip/mirror/border surface, `virtual IsWebcam`/`virtual IsImageSource`/`virtual IsZoomLayer` (TASK 52); `ToggleClipShape` + persisted `RectWidth`/`RectHeight` (pre-Round rect so round→rect restores after reload) |
 | `ZoomSceneElement.cs` | **Transient zoom box (TASK 52, creator-corrected 2026-10-08):** carries the box rect AND the anchored `CaptureX`/`CaptureY` (the fixed box/2 capture window set on `ActivateZoom`; moving the box never touches it). `IsZoomActive` flips `Kind` Static→Dynamic (leaves the baked base while active); never persisted (LayoutStore save skips non-Source/non-WebcamSceneConfig rows), never shown in the layers list or the element template (`IsZoomLayer` gates both). The compositor SKIPS the active element in every layer loop and draws its 2x content LAST (layer n+1) via `ZoomMagnifier`. |
 | `Webcam.cs` | Singleton webcam identity: `Id`, `DeviceId`, `Name` (one row app-wide) |
 | `WebcamSceneConfig.cs` | Per-scene webcam placement (subclass of `SceneElement`): geometry + `IsVisible` + border (`BorderColor`/`BorderOpacity`/`BorderWidth`/`BorderAnimation`) + `VideoImageSource`; `WebcamId` links to `Webcam` |
 | `QualityOption.cs` | Resolution tier record `(Display, Fps, Bitrate, Width, Height)`; `Label` formats as `1080p60 (8Mbps)` — drives the bottom-bar dropdown and the output-rect math |
 | `StreamConfig.cs` | `StreamConfig` (note: `TargetBitrate`/`Resolution` defaults are stale — not yet wired to the dropdown), `StreamHealth` (bitrate/FPS/dropped/duration), `StreamStatus` enum |
 | `MicStatus.cs` | Footer mic indicator: `NotConnected` / `Connected` / `Problem` — the state behind the MIC button's status dot (red = no device/capture off, green = capturing, yellow = a requested mic failed: in use/unplugged) |
-| `YouTube.cs` | `YouTubeChannel` and `ChatMessage` (chat feed) |
+| `YouTube.cs` | `YouTubeChannel` and `ChatMessage` (chat feed) — since TASK 43 every message carries `Kind` (`ChatEventKind` None/SuperChat/SuperSticker/NewMember/MemberGift/GiftReceived/MemberMilestone) + event payload fields (`SuperChatDisplayString`, `SuperStickerDescription`, `GiftNewMembersCount`, `GifterName`, `MilestoneMonths`) |
 | `Socials.cs` | **Social bar** (global layer, never a Source): `SocialService` enum (YouTube/Twitch/X/Instagram/TikTok/Facebook/Discord/Kick/Threads/Bluesky/GitHub/LinkedIn/Pinterest/Snapchat/Reddit/WhatsApp/Telegram/Link/Website/**Fediverse**), `SocialEntry` (Service/Handle/ProfileUrl/`FediverseSoftware`), `SocialsConfig` (Entries + `BarPosition` Top/Bottom + `BarEnabled` on/off — `BarJustify` dropped, column back-compat), `SocialServiceIcons` (canonical URL builder + `DetectService` (URL domain / fediverse `@user@domain` → **Fediverse** / bare→Website) + bundled SVG logo path data per service (`LogoDataFor`) + `LogoDataForFediverse(software)` mapping nodeinfo software names (mastodon/peertube/pixelfed/misskey/lemmy/pleroma/firefish) to logos with a generic fediverse glyph fallback (`FediverseIconData`) + `LockedIconData`/`DoNotIconData` — initials/colors gone) |
 Related: [`ViewModels/index.md`](../ViewModels/index.md) consume these;
@@ -28,6 +28,14 @@ ytLlive assumes you already have a YouTube creator account — connecting uses "
 to link that existing account. **ytLlive does not create accounts.** If you don't have a YouTube
 channel yet, set one up on YouTube first, then connect it here.
 ## Audio Assumption
 ytLlive uses your **default** microphone and desktop/game output — it never hunts for a device or
 contends for one. **It assumes your audio is already configured and working** (default input and
 output set, not hijacked by another app). Audio issues are a Windows/device matter outside ytLlive's
 scope: we don't debug, detect, or try to fix them. If it doesn't sound right, fix the system's audio
 settings first — it's on the OS, not on us.
 ## Run
 ```bash
@@ -37,25 +45,28 @@ dotnet run
 ## Version Roadmap
-| Version | Scope |
+**v1 is the finished product** (creator ruling, 2026-09-01 — there are no v1.x releases).
-|---------|-------|
+Everything still queueing lands in v1; anything not on the feature list is on the closed
-| v0.1     | Scene/source management, YouTube RTMP ingest, YouTube OAuth2, live chat, stream health |
+**"Out of product — permanently"** list in `TASKS.md` — read that page before asking for a feature.
-| v0.2     | Recording to local file |
+
-| v0.3     | Stream scheduling |
+What v1 ships: the five-scene director's control surface, webcam + screen capture, media + web +
-| v0.4     | Multi-destination restreaming |
+text sources, chat on-stream, the social bar, mic/desktop audio with auto-duck and TRAX, local
-| 1.0      | General availability |
+recording, variable quality tiers with auto step-down, one-click go-live + scheduling, stream
 resilience (auto-reconnect inside YouTube's grace, one-click back on air), built-in monetization
 awareness (reward capture, session reports, YPP journey tracker), Alerts — all free and ungated;
 the paid tier only removes the branding flash.
 ## Structure
 | Path | Role |
 |------|------|
-| `Models/` | Scene, Source, QualityOption, StreamConfig, StreamHealth, YouTube channel/chat, Socials (social bar) |
+| `Models/` | Scene, Source, WebcamSceneConfig, SceneElement, SceneCatalog, QualityOption, StreamConfig/Health, chat, Socials, BroadcastMetadata, Music, MicStatus |
-| `ViewModels/` | MainViewModel — scenes, stream controls, chat; GoLiveViewModel, ReuseImageViewModel, SocialsDialogViewModel |
+| `ViewModels/` | MainViewModel (partial classes per area) + dialogs: GoLive, CameraPicker, MicPicker, HotkeyConfig, Socials, LiveBroadcastForm |
-| `Services/` | YouTubeAuthService (OAuth2), YouTubeStreamService (broadcast/health), YouTubeChatService (chat polling), LayoutStore (SQLite), SocialValidator (social link/fediverse validation + nodeinfo icon resolution) |
+| `Services/` | YouTube (OAuth, streams/broadcasts, chat polling), LayoutStore (SQLite), capture (camera/screen-capture/media-file via FFmpeg), SceneCompositor + FramePump, FFmpeg encoder + RTMP, audio pipeline (WASAPI loopback + mic, mixer, filters, ducker, limiter, TRAX), SocialValidator, notifications, hotkeys, SceneGraph, ChatOverlayLayer |
-| `Helpers/` | ViewModelBase, RelayCommand, ImageCache, AppLog, FocusPreservingListBox, OAuthCredentials |
+| `Helpers/` | ViewModelBase, RelayCommand, ImageCache, AppLog, TokenStore (DPAPI), OAuthCredentials, converters |
 | `Themes/` | `Controls.xaml` — the dark-theme control styles, merged once in `App.xaml` |
-| `MainWindow.xaml` | Dark-theme main UI: scene/source panel, preview, chat, status bar |
+| `MainWindow.xaml` | Dark-theme control surface: thumbnails + central preview, two-state left panel (layers/properties ↔ live chat), top bar, footer |
-| `SocialsDialog.xaml` | Social Media Site Promotion dialog — 6-slot social bar editor with sign-in gate and validation |
+| `Distribution.md` | GA-time plan: signing, installer, EULA, hardening — executed as TASK 36 |
 ## Docs (memory map)
@@ -1,8 +1,8 @@
 <Window x:Class="ytLive.RenameRecordingDialog"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
-        Title="Rename Recording" Height="230" Width="460"
+        Title="Rename Recording" Height="304" Width="460"
-        Icon="/Assets/llamacasty-icon.png"
+        Icon="/ytLive;component/Assets/llamacasty-icon.png"
        WindowStartupLocation="CenterOwner" ResizeMode="NoResize"
        ShowInTaskbar="False" Background="#1a1a2e">
@@ -32,7 +32,7 @@
                    Margin="0,20,0,0">
            <Button Content="Cancel" Click="Cancel_Click"
                    Style="{StaticResource YtButtonSecondary}" Margin="0,0,8,0"/>
-            <Button Content="Save" Click="Save_Click" Style="{StaticResource YtButton}" MinWidth="90"/>
+            <Button Content="Save" Click="Save_Click" Style="{StaticResource YtButton}" MinWidth="90" x:Name="SaveRecordingButton"/>
        </StackPanel>
    </Grid>
 </Window>
@@ -6,12 +6,16 @@ namespace ytLive;
 /// <summary>Modal that lets the creator rename an auto-named recording before it is
 /// finalized. Returns the chosen file stem (no extension) via <see cref="ResultFileName"/>,
-/// or <c>null</c> on Cancel / keep-auto-name.</summary>
+/// or <c>null</c> when the creator cleared the box and hit Save (keep the auto name).
 /// <para><c>DialogResult == false</c> means DISCARD — the caller deletes the footage
 /// rather than saving it (CREATOR RULING 2026-09-26). Enter on the pre-filled default
 /// is a Save.</para></summary>
 public partial class RenameRecordingDialog : Window
 {
    private readonly string _autoStem;
-    /// <summary>Stem (no extension) the creator chose, or <c>null</c> to keep auto-name.</summary>
+    /// <summary>Stem (no extension) the creator chose, or <c>null</c> when the box was
    /// cleared on an explicit Save. Never set on Cancel.</summary>
    public string? ResultFileName { get; private set; }
    public RenameRecordingDialog(string autoStem)
@@ -0,0 +1,227 @@
 using System.Diagnostics;
 using System.IO;
 using ytLive.Helpers;
 using ytLive.Services.Audio;
 using ytLive.Services.Encoder;
 namespace ytLive.Services;
 /// <summary>
 /// TASK 47: one alert clip's playback — video frames + on-stream audio from the
 /// same file, both paced to real time. The alert box owns a decoder per event
 /// (start at play, dispose at drain) — unlike MediaSource's app-wide refcounted
 /// session, an alert REPLAYS the same clip each event, so a fresh decode per
 /// play is required. Video is rawvideo BGRA scaled to the box rect (the
 /// <see cref="MediaVideoSource"/> shape); audio is ffmpeg <c>f32le</c> at the
 /// mixer's native 48 kHz stereo (so the mixer ring needs no resampler). The
 /// fade is applied by the alert layer, not here.
 /// </summary>
 public interface IAlertClipDecoder : IDisposable
 {
    /// <summary>Starts the decode loop (video + audio); raises the events off the
    /// calling thread. Paced to real time so playback matches wall clock.</summary>
    void Start();
    /// <summary>Stops and kills any running decode subprocesses.</summary>
    void Stop();
    /// <summary>One decoded video frame (box-sized, straight-alpha BGRA).</summary>
    event Action<VideoFrame>? FrameAvailable;
    /// <summary>One chunk of on-stream audio (48 kHz stereo float).</summary>
    event Action<AudioSample>? AudioReady;
    /// <summary>Raised once when both streams have fully played out.</summary>
    event Action? Completed;
 }
 /// <summary>Default <see cref="IAlertClipDecoder"/>: two ffmpeg subprocesses on
 /// the same file. Video via <see cref="RawVideoFrameReader"/> on a <c>rawvideo
 /// bgra</c> pipe (-an), audio via an <c>f32le -ac 2 -ar 48000</c> pipe (-vn).
 /// The seams (locator, process factory, frame-rate probe, delay) let tests drive
 /// a fake decoder without a real codec or Windows.</summary>
 public sealed class AlertClipDecoder : IAlertClipDecoder
 {
    public event Action<VideoFrame>? FrameAvailable;
    public event Action<AudioSample>? AudioReady;
    public event Action? Completed;
    private const int AudioSampleRate = 48000;
    private const int AudioChannels = 2;
    private const int AudioChunkFloats = 4800; // 50ms of stereo
    private readonly string _path;
    private readonly int _width;
    private readonly int _height;
    private readonly IFfmpegLocator _locator;
    private readonly Func<IDecodeProcess> _processFactory;
    private readonly IFrameRateProbe? _probe;
    private readonly Func<TimeSpan, CancellationToken, Task> _delay;
    private readonly CancellationTokenSource _cts = new();
    private Task? _run;
    public AlertClipDecoder(
        string path,
        int width,
        int height,
        IFfmpegLocator locator,
        Func<IDecodeProcess> processFactory,
        IFrameRateProbe? frameRateProbe = null,
        Func<TimeSpan, CancellationToken, Task>? delay = null)
    {
        _path = path;
        _width = width;
        _height = height;
        _locator = locator;
        _processFactory = processFactory;
        _probe = frameRateProbe;
        _delay = delay ?? ((t, ct) => Task.Delay(t, ct));
    }
    public void Start()
    {
        if (_run != null) return;
        _run = Task.Run(RunAsync, CancellationToken.None);
    }
    public void Stop() => _cts.Cancel();
    public void Dispose()
    {
        _cts.Cancel();
        _cts.Dispose();
    }
    private async Task RunAsync()
    {
        var ct = _cts.Token;
        var videoFrames = 0;
        var audioChunks = 0;
        var failed = false;
        try
        {
            double? frameRate = null;
            if (_probe != null)
                frameRate = await _probe.ProbeAsync(_path, ct).ConfigureAwait(false);
            var frameDuration = frameRate is > 0 ? TimeSpan.FromSeconds(1.0 / frameRate.Value) : TimeSpan.Zero;
            var ffmpegPath = await _locator.LocateAsync(ct).ConfigureAwait(false);
            var videoTask = RunVideoAsync(ffmpegPath, frameDuration, ct);
            var audioTask = RunAudioAsync(ffmpegPath, ct);
            videoFrames = await videoTask.ConfigureAwait(false);
            audioChunks = await audioTask.ConfigureAwait(false);
        }
        catch (OperationCanceledException)
        {
            failed = true;
            return;
        }
        catch (Exception ex)
        {
            // A failed decode is not fatal: the alert layer falls back to the six
            // animations (or the frame it already holds) exactly as a missing file.
            // Logged so a silent blank box traces back to a decode failure.
            failed = true;
            AppLog.Write(ex, $"Alert clip decode failed ({Path.GetFileName(_path)})");
        }
        if (!ct.IsCancellationRequested)
        {
            AppLog.Write($"Alert clip end: {Path.GetFileName(_path)} frames={videoFrames} audioChunks={audioChunks} failed={failed}");
            Completed?.Invoke();
        }
    }
    private async Task<int> RunVideoAsync(string ffmpegPath, TimeSpan frameDuration, CancellationToken ct)
    {
        var args =
            $"-hide_banner -loglevel error -i \"{_path}\" " +
            $"-f rawvideo -pix_fmt bgra -vf scale={_width}:{_height} -an -";
        using var process = _processFactory();
        process.Start(new ProcessStartInfo
        {
            FileName = ffmpegPath,
            Arguments = args,
            UseShellExecute = false,
            RedirectStandardOutput = true,
            RedirectStandardError = true,
            CreateNoWindow = true,
        });
        var reader = new RawVideoFrameReader(_width, _height);
        var buffer = new byte[65536];
        var stream = process.StandardOutput;
        var frames = 0;
        while (!ct.IsCancellationRequested && !process.HasExited)
        {
            var read = await stream.ReadAsync(buffer, 0, buffer.Length, ct).ConfigureAwait(false);
            if (read <= 0) break;
            var chunk = new byte[read];
            Buffer.BlockCopy(buffer, 0, chunk, 0, read);
            foreach (var frame in reader.Feed(chunk))
            {
                frames++;
                FrameAvailable?.Invoke(frame);
                if (frameDuration > TimeSpan.Zero)
                    await _delay(frameDuration, ct).ConfigureAwait(false);
            }
        }
        return frames;
    }
    private async Task<int> RunAudioAsync(string ffmpegPath, CancellationToken ct)
    {
        var args =
            $"-hide_banner -loglevel error -i \"{_path}\" " +
            $"-f f32le -ac {AudioChannels} -ar {AudioSampleRate} -vn -";
        using var process = _processFactory();
        process.Start(new ProcessStartInfo
        {
            FileName = ffmpegPath,
            Arguments = args,
            UseShellExecute = false,
            RedirectStandardOutput = true,
            RedirectStandardError = true,
            CreateNoWindow = true,
        });
        var stream = process.StandardOutput;
        var raw = new byte[65536];
        var carry = new byte[0];
        var floatScratch = new float[AudioChunkFloats];
        var floatIndex = 0;
        var chunks = 0;
        // The pipe is byte-delimited only: a read may split a float, so leftover
        // bytes are carried into the next read instead of dropped (a dropped
        // half-float would desync the entire stream).
        while (!ct.IsCancellationRequested && !process.HasExited)
        {
            var read = await stream.ReadAsync(raw, 0, raw.Length, ct).ConfigureAwait(false);
            if (read <= 0) break;
            var total = carry.Length + read;
            var bytes = total <= raw.Length ? raw : new byte[total];
            if (carry.Length > 0)
            {
                Buffer.BlockCopy(carry, 0, bytes, 0, carry.Length);
                Buffer.BlockCopy(raw, 0, bytes, carry.Length, read);
            }
            var floatsTo = total - (total % 4);
            for (var i = 0; i < floatsTo && floatIndex < floatScratch.Length; i += 4)
                floatScratch[floatIndex++] = BitConverter.ToSingle(bytes, i);
            carry = total > floatsTo ? bytes[floatsTo..total] : new byte[0];
            while (floatIndex == floatScratch.Length)
            {
                chunks++;
                AudioReady?.Invoke(new AudioSample(floatScratch, AudioSampleRate, AudioChannels));
                // Pace the NEXT chunk so the whole clip's audio lands at real-time
                // cadence (the fade in the alert layer tracks the same wall clock).
                await _delay(TimeSpan.FromSeconds(AudioChunkFloats / (double)(AudioSampleRate * AudioChannels)), ct).ConfigureAwait(false);
                floatScratch = new float[AudioChunkFloats];
                floatIndex = 0;
            }
        }
        return chunks;
    }
 }
@@ -0,0 +1,541 @@
 using System.Collections.Generic;
 using System.Linq;
 using System.Windows;
 using System.Windows.Media;
 using System.Windows.Media.Imaging;
 using System.Windows.Threading;
 using ytLive.Helpers;
 using ytLive.Models;
 using ytLive.Services.Audio;
 using ytLive.Services.Compositor;
 namespace ytLive.Services;
 /// <summary>
 /// The native alert box (OBS-style celebration zone, no third party). Owns the
 /// event queue and the animation clock: <see cref="ChatEventKind"/> events from
 /// the chat feed are enqueued one-at-a-time and played through a celebration
 /// animation (<see cref="AlertRenderer"/>) OR — when the alert-box video is
 /// configured and resolves — through a decoded clip. Frames are served to the
 /// stream compositor via <see cref="RenderFrame"/> and mirrored to the preview
 /// via <see cref="UpdatePreview"/>. Idle = transparent (null frame); playback is
 /// advanced by a 33ms dispatch ticker. The clock is exposed as
 /// <see cref="Advance"/> so tests drive playback deterministically without the
 /// timer. Ordinary chat rows (<see cref="ChatEventKind.None"/>) never enqueue —
 /// a subscriber mention is a chat row, not an alert.
 ///
 /// TASK 47 (Stream Alerts video): a video-backed alert replaces the animation
 /// while a clip decodes (<see cref="IAlertClipDecoder"/>, one per play). The
 /// clip plays at its own media pace; the layer applies a ~300ms fade-in/out
 /// alpha envelope to the frames AND the audio samples (freeze-frame fade-out on
 /// the tail), clips the alert to the clip length, and forwards the scaled audio
 /// to the mixer's alert ring via <paramref name="audioSink"/> (no duck). The
 /// per-source config (path/default/ticker/volume) is resolved through
 /// <paramref name="clipPathResolver"/>; the ticker strip is served via
 /// <see cref="AlertTickerFrame"/>.
 /// </summary>
 public sealed class AlertOverlayLayer : IDisposable
 {
    /// <summary>The fade-in/out ramp length (video alpha AND audio gain). Measured
    /// against a real clip in the AlertLayerVideoTests unit; keep the ramp short
    /// enough to read as a "pop-in" on stream (see ai.md).</summary>
    internal const double FadeDurationSeconds = 0.30;
    /// <summary>How long an alert waits for the first decoded frame or audio slab
    /// before treating the clip as unplayable and falling back to the animations
    /// (a silent decoder must never blank the alert box).</summary>
    internal const double NoFrameFallbackSeconds = 1.0;
    private static readonly TimeSpan TickInterval = TimeSpan.FromMilliseconds(33);
    private readonly AlertRenderer _renderer;
    private readonly Func<string, int, int, IAlertClipDecoder>? _clipDecoderFactory;
    private readonly Func<Source, string?>? _clipPathResolver;
    private readonly Action<AudioSample>? _audioSink;
    private readonly Action<VideoFrame?>? _tickerPreviewSink;
    private readonly Queue<ChatMessage> _queue = new();
    private readonly DispatcherTimer? _ticker;
    private ChatMessage? _current;
    private Source? _currentBox;
    private IAlertClipDecoder? _clip;
    private VideoFrame? _latestClipFrame;
    private bool _clipEof;
    private double _clipEofElapsed;
    private int _clipWidth;
    private int _clipHeight;
    private bool _clipSawFrame;
    private bool _clipAudioHeard;
    private string? _tickerText;
    private AlertDisplayMethod _tickerMethod = AlertDisplayMethod.TickerScroll;
    private double _elapsed;
    private IEnumerable<Scene>? _scenes;
    private int _contentVersion;
    private int _frameVersion = -1;
    private string? _frameKey;
    private VideoFrame? _cachedFrame;
    private DateTime _lastPreviewLog = DateTime.MinValue;
    public AlertOverlayLayer(
        AlertRenderer renderer,
        Func<string, int, int, IAlertClipDecoder>? clipDecoderFactory = null,
        Func<Source, string?>? clipPathResolver = null,
        Action<AudioSample>? audioSink = null,
        Action<VideoFrame?>? tickerPreviewSink = null)
    {
        _renderer = renderer;
        _clipDecoderFactory = clipDecoderFactory;
        _clipPathResolver = clipPathResolver;
        _audioSink = audioSink;
        _tickerPreviewSink = tickerPreviewSink;
        if (Application.Current != null)
        {
            _ticker = new DispatcherTimer { Interval = TickInterval };
            _ticker.Tick += (_, _) =>
            {
                Advance(TickInterval.TotalSeconds);
                RefreshAlertPreviews();
            };
        }
    }
    /// <summary>Production entry from the chat feed: enqueue one event. Messages
    /// arrive on the chat poller thread, so this marshals to the UI thread (same
    /// rule as <see cref="ChatOverlayLayer.OnMessageReceived"/>) — the preview
    /// writes create WPF <see cref="WriteableBitmap"/> instances, and creating a
    /// DependencySource off the UI thread crashes the WPF binding engine
    /// (ArgumentException "Must create DependencySource on same Thread").</summary>
    public void OnMessageReceived(ChatMessage message, IEnumerable<Scene> scenes)
    {
        var app = Application.Current;
        if (app != null && !app.Dispatcher.CheckAccess())
        {
            app.Dispatcher.Invoke(() => Ingest(message, scenes));
            return;
        }
        Ingest(message, scenes);
    }
    private void Ingest(ChatMessage message, IEnumerable<Scene> scenes)
    {
        _scenes = scenes;
        Enqueue(message);
        _ticker?.Start();
        RefreshAlertPreviews();
    }
    /// <summary>Queue an event (pure — also the test seam). Chat rows carry
    /// <see cref="ChatEventKind.None"/> and are ignored: no alert for a mention.</summary>
    public void Enqueue(ChatMessage message)
    {
        if (message.Kind == ChatEventKind.None) return;
        if (_queue.Count >= 10) return; // back-to-back floods drop the tail, never stall playback
        _queue.Enqueue(message);
        if (_current == null)
        {
            _current = _queue.Dequeue();
            _elapsed = 0;
            BeginClip();
        }
        _contentVersion++;
    }
    /// <summary>Advance the playback clock (the ticker's beat — and the test seam;
    /// tests call this directly and never start the timer). Draining the queue to
    /// nothing stops the ticker and leaves the box transparent.</summary>
    public void Advance(double deltaSeconds)
    {
        // Video-backed alert: duration is clip-driven. The clip plays at media
        // pace; once it EOFs the last frame sweeps through the fade-out before
        // the alert moves on (a hard cut at EOF would pop, not fade).
        if (_clip != null)
        {
            _elapsed += deltaSeconds;
            // A decoder that starts but produces not a single frame (or slab of
            // audio) is dead weight — the box would sit transparent for the whole
            // alert. Give it a short grace, then fall back to the animations so an
            // alert ALWAYS renders (the live decode failure at 2026-09-26 11:44 was
            // this exact void, invisible in the log).
            if (!_clipSawFrame && !_clipAudioHeard && _elapsed >= NoFrameFallbackSeconds)
            {
                System.Diagnostics.Debug.WriteLine("Alert clip yielded no frames in 1s — falling back to the animation");
                StopClip();
                _elapsed = 0;
                _contentVersion++;
                return;
            }
            if (_clipEof && _elapsed - _clipEofElapsed >= FadeDurationSeconds)
            {
                _clipEof = false;
                StopClip();
                _current = null;
                _elapsed = 0;
                AdvanceToNext();
            }
            _contentVersion++;
            return;
        }
        if (_current == null)
        {
            if (_queue.Count == 0) return;
            _current = _queue.Dequeue();
            _elapsed = 0;
            BeginClip();
            _contentVersion++;
            return;
        }
        _elapsed += deltaSeconds;
        if (_elapsed >= DurationOf(_current))
        {
            _current = null;
            _elapsed = 0;
            AdvanceToNext();
        }
        _contentVersion++;
    }
    /// <summary>Whether an alert is currently playing or queued.</summary>
    public bool IsPlaying => _current != null || _queue.Count > 0;
    /// <summary>The live-output frame for one AlertBox element: the decoded clip
    /// frame (faded) while a clip is active, else the animation frame, null
    /// (transparent) when idle.</summary>
    public VideoFrame? RenderFrame(Source alertBox)
    {
        if (_current == null)
        {
            _frameKey = null;
            return null;
        }
        if (_clip != null)
            return RenderClipFrame(alertBox);
        var width = (int)Math.Max(1, alertBox.Width);
        var height = (int)Math.Max(1, alertBox.Height);
        var key = $"{width}x{height}|{_current.Id}|{Progress()}";
        if (_frameKey == key && _frameVersion == _contentVersion)
            return _cachedFrame;
        var app = Application.Current;
        if (app != null && !app.Dispatcher.CheckAccess())
        {
            var capturedKey = key;
            var capturedVersion = _contentVersion;
            return app.Dispatcher.Invoke(() =>
            {
                if (_frameKey == capturedKey && _frameVersion == capturedVersion)
                    return _cachedFrame;
                return RenderCore(alertBox, width, height, capturedKey, capturedVersion);
            });
        }
        return RenderCore(alertBox, width, height, key, _contentVersion);
    }
    /// <summary>The ticker strip as the alert box shows it: a marquee, a pulse or a
    /// static pill naming the event while an alert plays, else null. Pure byte-math
    /// per call so the frame pump can read it on any thread (the text strip is
    /// rasterized once on the UI thread and cached).
    /// <para><b>Creator ruling 2026-09-26:</b> the strip is composited INSIDE the
    /// Stream Alerts box, not as a full-width bar at the top edge of the frame — "the
    /// ticker should appear over the stream alerts video, not over the entire preview
    /// window". So the frame is rendered at the box's own size and carries the box's
    /// origin on <see cref="VideoFrame.Placement"/>; every blit site reads
    /// <see cref="VideoFrame.OriginX"/>/<see cref="VideoFrame.OriginY"/> instead of
    /// a hardcoded 0. <b>No alert box in the scene means no ticker at all</b> — there
    /// is no longer a global position for it to live in.</para></summary>
    public VideoFrame? AlertTickerFrame
    {
        get
        {
            if (_current == null || string.IsNullOrWhiteSpace(_tickerText)) return null;
            var box = _currentBox;
            if (box == null) return null;
            var w = (int)Math.Max(1, Math.Round(box.Width));
            var h = (int)Math.Max(1, Math.Min(
                Math.Round(box.Height), AlertTickerRenderer.Height));
            var frame = AlertTickerRenderer.Render(
                _tickerText!, _elapsed, _tickerMethod, AlertSeconds(),
                TickerReadsPerAlert, w, h);
            return frame == null
                ? null
                : new VideoFrame(frame.Width, frame.Height, frame.BgraPixels)
                {
                    Placement = ((int)Math.Round(box.X), (int)Math.Round(box.Y)),
                };
        }
    }
    /// <summary>How many times the marquee must cross the frame per alert, so the
    /// announcement is actually readable inside a 10s clip (2026-09-26: the old
    /// fixed 140px/s took ~17s per pass, so a 10s alert showed it barely once).</summary>
    internal const int TickerReadsPerAlert = 3;
    /// <summary>Assumed alert length for the marquee rhythm. The clip's real length
    /// isn't known until it EOFs, and the shipped default clip is 10s — the number
    /// the creator's "three reads" target is stated against.</summary>
    internal const double AssumedAlertSeconds = 10.0;
    private double AlertSeconds() => _clip != null ? AssumedAlertSeconds : DurationOf(_current!);
    private VideoFrame? RenderClipFrame(Source alertBox)
    {
        var frame = _latestClipFrame;
        if (frame == null) return null;
        var w = (int)Math.Max(1, alertBox.Width);
        var h = (int)Math.Max(1, alertBox.Height);
        if (frame.Width != w || frame.Height != h)
            frame = StretchMath.BilinearScale(frame, w, h);
        var fade = FadeAt();
        if (fade >= 1.0) return frame;
        // Straight-alpha source-over on the compositor side: scale the source
        // alpha by the envelope so the clip blends out (a 680x200 copy per fade
        // tick is trivial; outside the ramps fade==1 returns the raw frame).
        var copy = new byte[frame.BgraPixels.Length];
        Buffer.BlockCopy(frame.BgraPixels, 0, copy, 0, copy.Length);
        var a = (byte)(fade * 255 + 0.5);
        for (var i = 3; i < copy.Length; i += 4)
            copy[i] = (byte)((copy[i] * a) >> 8);
        return new VideoFrame(frame.Width, frame.Height, copy);
    }
    private double FadeAt()
    {
        if (_clip == null) return 1.0;
        if (_clipEof)
            return Math.Clamp(1.0 - (_elapsed - _clipEofElapsed) / FadeDurationSeconds, 0.0, 1.0);
        return Math.Clamp(_elapsed / FadeDurationSeconds, 0.0, 1.0);
    }
    private void BeginClip()
    {
        StopClip();
        _tickerText = null;
        if (_current == null) return;
        var box = _scenes?.SelectMany(s => s.Elements).OfType<Source>()
            .FirstOrDefault(s => s.Type == SourceType.AlertBox);
        _currentBox = box;
        if (box != null && box.AlertShowTicker)
        {
            _tickerText = ComposeTicker(_current);
            _tickerMethod = box.AlertDisplayMethod;
        }
        if (box == null || _clipDecoderFactory == null) return;
        var path = _clipPathResolver?.Invoke(box);
        if (string.IsNullOrWhiteSpace(path)) return;
        _clipWidth = (int)Math.Max(1, box.Width);
        _clipHeight = (int)Math.Max(1, box.Height);
        try
        {
            _clipSawFrame = false;
            _clipAudioHeard = false;
            _clip = _clipDecoderFactory(path, _clipWidth, _clipHeight);
            _clip.FrameAvailable += OnClipFrame;
            _clip.AudioReady += OnClipAudio;
            _clip.Completed += OnClipCompleted;
            _clip.Start();
            AppLog.Write($"Alert clip start: box {box.Id} path '{path}' {_clipWidth}x{_clipHeight}");
        }
        catch (Exception ex)
        {
            AppLog.Write(ex, "Alert clip setup failed");
            StopClip(); // decode setup failed (bad path) — fall back to animations
        }
    }
    private void StopClip()
    {
        var clip = _clip;
        _clip = null;
        _latestClipFrame = null;
        _clipEof = false;
        _clipSawFrame = false;
        _clipAudioHeard = false;
        if (clip == null) return;
        clip.FrameAvailable -= OnClipFrame;
        clip.AudioReady -= OnClipAudio;
        clip.Completed -= OnClipCompleted;
        try { clip.Stop(); } catch { /* already stopped */ }
        clip.Dispose();
    }
    private void OnClipFrame(VideoFrame frame)
    {
        _clipSawFrame = true;
        _latestClipFrame = frame;
    }
    private void OnClipCompleted()
    {
        _clipEof = true;
        _clipEofElapsed = _elapsed;
    }
    private void OnClipAudio(AudioSample sample)
    {
        if (_audioSink == null) return;
        _clipAudioHeard = true;
        var volume = (float)Math.Clamp(_currentBox?.AlertVideoVolume ?? 1.0, 0.0, 1.0);
        if (volume <= 0f) return;
        var fade = FadeAt();
        if (fade <= 0.0) return;
        var data = sample.Samples;
        if (fade < 1.0 || Math.Abs(volume - 1f) > 0.001f)
        {
            data = new float[data.Length];
            var gain = volume * (float)fade;
            for (var i = 0; i < sample.Samples.Length; i++)
                data[i] = sample.Samples[i] * gain;
        }
        _audioSink(new AudioSample(data, sample.SampleRate, sample.Channels));
    }
    private void AdvanceToNext()
    {
        if (_queue.Count > 0)
        {
            _current = _queue.Dequeue();
            _elapsed = 0;
            BeginClip();
        }
        else
        {
            _ticker?.Stop();
        }
    }
    private VideoFrame? RenderCore(Source alertBox, int width, int height, string key, int version)
    {
        _frameKey = key;
        _frameVersion = version;
        if (_current == null) return _cachedFrame = null;
        return _cachedFrame = _renderer.Render(_current, Progress(), width, height);
    }
    private double Progress()
    {
        if (_current == null) return 0;
        return Math.Clamp(_elapsed / DurationOf(_current), 0.0, 1.0);
    }
    private static double DurationOf(ChatMessage m) => m.Kind switch
    {
        ChatEventKind.SuperChat => 4.6,
        ChatEventKind.SuperSticker => 4.2,
        ChatEventKind.NewMember => 4.0,
        ChatEventKind.MemberGift => 5.0,
        ChatEventKind.GiftReceived => 4.4,
        ChatEventKind.MemberMilestone => 4.8,
        _ => 4.0,
    };
    private static string ComposeTicker(ChatMessage m)
    {
        var label = m.Kind switch
        {
            ChatEventKind.SuperChat => "Super Chat",
            ChatEventKind.SuperSticker => "Super Sticker",
            ChatEventKind.NewMember => "New Member",
            ChatEventKind.MemberGift => "Membership Gift",
            ChatEventKind.GiftReceived => "Gifted Membership",
            ChatEventKind.MemberMilestone => "Member Milestone",
            _ => "Stream Alert",
        };
        var amount = m.Kind is ChatEventKind.SuperChat or ChatEventKind.SuperSticker
            && m.SuperChatDisplayString is { Length: > 0 } s
                ? $" · {s}"
                : "";
        return $"{m.AuthorName} — {label}{amount}";
    }
    /// <summary>Render the current state onto one AlertBox preview (mirrors chat):
    /// the playing frame, or null when idle so the source shows nothing until an
    /// event actually fires.</summary>
    public void UpdatePreview(Source alertBox)
    {
        try
        {
            var frame = RenderFrame(alertBox);
            // Preview eyes (TASK 47, 2026-09-26): a healthy decode painted nothing on
            // the canvas. UpdatePreview swallows its failures to Debug, so say once a
            // second whether the box is being handed a frame at all.
            if (IsPlaying)
            {
                var now = DateTime.UtcNow;
                if (now - _lastPreviewLog >= TimeSpan.FromSeconds(1))
                {
                    _lastPreviewLog = now;
                    AppLog.Write($"Alert preview: box {alertBox.Id} frame="
                        + (frame == null ? "null" : $"{frame.Width}x{frame.Height} a{frame.BgraPixels[3]}"));
                }
            }
            if (frame == null)
            {
                alertBox.VideoImageSource = null;
                return;
            }
            var width = (int)Math.Max(1, alertBox.Width);
            var height = (int)Math.Max(1, alertBox.Height);
            var bitmap = new WriteableBitmap(width, height, 96, 96, PixelFormats.Bgra32, null);
            bitmap.WritePixels(new Int32Rect(0, 0, width, height), frame.BgraPixels, frame.Stride, 0);
            alertBox.VideoImageSource = bitmap;
        }
        catch (Exception ex)
        {
            System.Diagnostics.Debug.WriteLine($"Alert preview failed: {ex.Message}");
        }
    }
    /// <summary>Wire property-change subscriptions for all AlertBox sources across
    /// every scene (geometry changes re-render), and clear/reset their previews.</summary>
    public void UpdateConfiguredBoxes(IEnumerable<Scene> scenes)
    {
        _scenes = scenes;
        foreach (var scene in scenes)
        foreach (var alertBox in scene.Elements.OfType<Source>().Where(s => s.Type == SourceType.AlertBox))
        {
            alertBox.PropertyChanged += (_, e) =>
            {
                if (e.PropertyName is nameof(Source.Width) or nameof(Source.Height))
                    UpdatePreview(alertBox);
            };
            UpdatePreview(alertBox);
        }
    }
    private void RefreshAlertPreviews()
    {
        // The announcement strip is a GLOBAL 1920px overlay, not a per-box frame, so
        // it gets its own sink: until this existed the strip went only to the frame
        // pump and was therefore invisible in the preview pane the creator watches
        // (2026-09-26 — "I do not see the scrolling text").
        _tickerPreviewSink?.Invoke(AlertTickerFrame);
        if (_scenes == null) return;
        foreach (var alertBox in _scenes.SelectMany(s => s.Elements).OfType<Source>()
                     .Where(s => s.Type == SourceType.AlertBox))
            UpdatePreview(alertBox);
    }
    public void Dispose()
    {
        _ticker?.Stop();
        _queue.Clear();
        _current = null;
        StopClip();
    }
 }
@@ -0,0 +1,389 @@
 using System.Globalization;
 using System.Windows;
 using System.Windows.Media;
 using System.Windows.Media.Imaging;
 using ytLive.Models;
 namespace ytLive.Services;
 /// <summary>
 /// Renders one event's celebration animation into a BGRA8 frame for the AlertBox.
 /// Six event kinds, six UNIQUE animations — each a distinct gesture, palette and
 /// layout (the creator's ruling: these are the monetization shout-outs and free
 /// branded product placement; a one-template recoloring loses all interest in two
 /// iterations). Each card carries the bottom-right brand line so every broadcast
 /// of an event is an in-video ad placement.
 ///
 /// <paramref name="t01"/> walks 0→1 over the whole animation; each kind splits it
 /// into enter / hold / exit phases with its own easing.
 /// </summary>
 public sealed class AlertRenderer
 {
    private const double EnterEnd = 0.16;
    private const double ExitStart = 0.80;
    private const string Brand = "made with LlamaCasty!";
    private static readonly CultureInfo Invariant = CultureInfo.InvariantCulture;
    private static readonly Color White = Colors.White;
    private static readonly Color[] ConfettiPalette =
    {
        Color.FromRgb(0xf4, 0x2f, 0x5f), Color.FromRgb(0xff, 0xd1, 0x66),
        Color.FromRgb(0x38, 0xb6, 0xf8), Color.FromRgb(0xa7, 0x8b, 0xfa),
        Color.FromRgb(0x39, 0xd3, 0x53),
    };
    public VideoFrame Render(ChatMessage e, double t01, int width, int height)
    {
        return e.Kind switch
        {
            ChatEventKind.SuperChat => SuperChat(e, t01, width, height),
            ChatEventKind.SuperSticker => SuperSticker(e, t01, width, height),
            ChatEventKind.NewMember => NewMember(e, t01, width, height),
            ChatEventKind.MemberGift => MemberGift(e, t01, width, height),
            ChatEventKind.GiftReceived => GiftReceived(e, t01, width, height),
            ChatEventKind.MemberMilestone => Milestone(e, t01, width, height),
            _ => SuperChat(e, t01, width, height),
        };
    }
    private static VideoFrame SuperChat(ChatMessage e, double t, int w, int h)
    {
        var dpi = 96.0;
        var visual = new DrawingVisual();
        using (var ctx = visual.RenderOpen())
        {
            var margin = Math.Max(w, h) * 0.03;
            var cardX = margin;
            var cardW = w - margin * 2;
            var cardH = h - margin * 2;
            var cardCX = cardX + cardW / 2;
            var enter = Clamp01(t / EnterEnd);
            var exit = Clamp01((t - ExitStart) / (1 - ExitStart));
            var exitEase = EaseInCubic(exit);
            var cardY = Lerp(h + cardH, margin, EaseOutCubic(enter));
            cardY = Lerp(cardY, -cardH, exitEase);
            DrawCard(ctx, cardX, cardY, cardW, cardH, "#0d3b2b", "#14532d", 14);
            DrawBrand(ctx, cardX, cardY, cardW, cardH);
            var shownAmount = e.SuperChatDisplayString
                ?? (e.SuperChatCurrency is { Length: > 0 } cur ? $"{cur}{e.SuperChatAmount:0.00}" : $"${e.SuperChatAmount:0.00}");
            var fontSize = cardH * 0.24;
            DrawCentered(ctx, shownAmount, cardCX, cardY + cardH * 0.24, fontSize, FontWeights.Bold, Color.FromRgb(0xff, 0xd1, 0x66), cardW);
            DrawCentered(ctx, e.AuthorName, cardCX, cardY + cardH * 0.56, cardH * 0.13, FontWeights.SemiBold, White, cardW);
            DrawCentered(ctx, e.Message, cardCX, cardY + cardH * 0.74, cardH * 0.10, FontWeights.Normal, Color.FromRgb(0xdd, 0xff, 0xf0), cardW * 0.92);
            if (t >= EnterEnd && t <= ExitStart)
            {
                var sweep = (t - EnterEnd) / (ExitStart - EnterEnd);
                var shineX = cardX + (sweep * 2 - 0.5) * cardW;
                ctx.DrawRectangle(
                    new LinearGradientBrush(
                        Colors.Transparent,
                        Color.FromArgb(0x30, 0xff, 0xff, 0xff),
                        new Point(0, 0),
                        new Point(1, 0)),
                    null,
                    new Rect(shineX - cardW * 0.25, cardY, cardW * 0.5, cardH));
            }
        }
        return CreateFrame(visual, w, h, dpi);
    }
    private static VideoFrame SuperSticker(ChatMessage e, double t, int w, int h)
    {
        var dpi = 96.0;
        var visual = new DrawingVisual();
        using (var ctx = visual.RenderOpen())
        {
            var margin = Math.Max(w, h) * 0.04;
            var cardW = w - margin * 2;
            var cardH = h - margin * 2;
            var cardCX = w / 2.0;
            var enter = Clamp01(t / EnterEnd);
            var exit = Clamp01((t - ExitStart) / (1 - ExitStart));
            var scale = EaseOutBack(enter) * (0.85 + 0.15 * (1 - exit));
            if (t > EnterEnd && t <= ExitStart)
                scale = 1.0 + 0.02 * Math.Sin(t * 26.0);
            var alpha = 1.0 - exit;
            ctx.PushOpacity(alpha);
            var slick = new RotateTransform(-6, w / 2.0, h / 2.0);
            ctx.PushTransform(slick);
            ctx.PushTransform(new ScaleTransform(scale, scale, w / 2.0, h / 2.0));
            DrawCard(ctx, margin, margin, cardW, cardH, "#4a044e", "#7e22ce", 20);
            DrawBrand(ctx, margin, margin, cardW, cardH);
            var desc = string.IsNullOrWhiteSpace(e.SuperStickerDescription) ? "SUPER STICKER" : e.SuperStickerDescription.ToUpperInvariant();
            DrawCentered(ctx, desc, cardCX, h / 2.0 - cardH * 0.12, cardH * 0.17, FontWeights.Bold, White, cardW * 0.9);
            DrawCentered(ctx, e.AuthorName, cardCX, h / 2.0 + cardH * 0.16, cardH * 0.12, FontWeights.SemiBold, Color.FromRgb(0xff, 0xb3, 0xd9), cardW * 0.9);
            var tier = e.SuperChatDisplayString ?? (e.SuperChatCurrency is { Length: > 0 } cur ? $"{cur}{e.SuperChatAmount:0.00}" : null);
            if (!string.IsNullOrWhiteSpace(tier))
                DrawCentered(ctx, tier, cardCX, h / 2.0 + cardH * 0.32, cardH * 0.10, FontWeights.Bold, Color.FromRgb(0xff, 0xd1, 0x66), cardW * 0.9);
            ctx.Pop();
            ctx.Pop();
            ctx.Pop();
        }
        return CreateFrame(visual, w, h, dpi);
    }
    private static VideoFrame NewMember(ChatMessage e, double t, int w, int h)
    {
        var dpi = 96.0;
        var visual = new DrawingVisual();
        using (var ctx = visual.RenderOpen())
        {
            var margin = Math.Max(w, h) * 0.035;
            var cardW = w - margin * 2;
            var cardH = h - margin * 2;
            var cardCX = w / 2.0;
            var enter = Clamp01(t / EnterEnd);
            var exit = Clamp01((t - ExitStart) / (1 - ExitStart));
            var cardY = Lerp(-cardH, margin, EaseOutCubic(enter));
            cardY = Lerp(cardY, h, EaseInCubic(exit));
            DrawCard(ctx, margin, cardY, cardW, cardH, "#2e1065", "#5b21b6", 16);
            DrawBrand(ctx, margin, cardY, cardW, cardH);
            if (t <= ExitStart)
            {
                var bandP = EaseOutCubic(Clamp01(t / 0.22));
                ctx.DrawRectangle(
                    new LinearGradientBrush(Color.FromArgb(0, 0xff, 0xff, 0xff), Colors.Transparent, new Point(0, 0), new Point(0, 1)),
                    null,
                    new Rect(margin, cardY + cardH * 0.30, cardW * bandP, cardH * 0.18));
            }
            DrawCentered(ctx, e.AuthorName, cardCX, cardY + cardH * 0.36, cardH * 0.22, FontWeights.Bold, White, cardW * 0.9);
            DrawCentered(ctx, "JOINED THE MEMBERSHIP", cardCX, cardY + cardH * 0.62, cardH * 0.11, FontWeights.SemiBold, Color.FromRgb(0xf5, 0xd0, 0xfe), cardW * 0.9);
            var level = string.IsNullOrWhiteSpace(e.MembershipLevel) ? "MEMBER" : e.MembershipLevel.ToUpperInvariant();
            DrawCentered(ctx, level, cardCX, cardY + cardH * 0.80, cardH * 0.10, FontWeights.Bold, Color.FromRgb(0xff, 0xd1, 0x66), cardW * 0.9);
        }
        return CreateFrame(visual, w, h, dpi);
    }
    private static VideoFrame MemberGift(ChatMessage e, double t, int w, int h)
    {
        var dpi = 96.0;
        var visual = new DrawingVisual();
        using (var ctx = visual.RenderOpen())
        {
            var margin = Math.Max(w, h) * 0.035;
            var cardW = w - margin * 2;
            var cardH = h - margin * 2;
            var cardCX = w / 2.0;
            var enter = Clamp01(t / EnterEnd);
            var exit = Clamp01((t - ExitStart) / (1 - ExitStart));
            var cardX = Lerp(-cardW, margin, EaseOutCubic(enter));
            cardX = Lerp(cardX, -cardW, EaseInCubic(exit));
            DrawCard(ctx, cardX, margin, cardW, cardH, "#422006", "#a16207", 16);
            DrawBrand(ctx, cardX, margin, cardW, cardH);
            var count = Math.Max(1, e.GiftNewMembersCount);
            var spread = 1.0 - exit;
            var hero = count > 1 ? $"×{count}" : "MEMBERSHIP";
            DrawCentered(ctx, hero, cardCX, margin + cardH * 0.24, cardH * 0.26, FontWeights.Bold, Color.FromRgb(0xff, 0xd1, 0x66), cardW * 0.8);
            DrawCentered(ctx, $"{e.AuthorName} is gifting", cardCX, margin + cardH * 0.52, cardH * 0.11, FontWeights.SemiBold, White, cardW * 0.9);
            var chipCount = Math.Min(count, 6);
            for (var i = 0; i < chipCount; i++)
            {
                var slot = (chipCount - 1) * 0.5;
                var gap = cardH * 0.13 * EaseOutCubic(Clamp01(t / 0.30)) * spread;
                var chipX = cardCX + (i - slot) * gap;
                var chipY = margin + cardH * 0.70 + Math.Sin((i + t * 6) * 2.4) * cardH * 0.015;
                ctx.DrawRoundedRectangle(
                    new SolidColorBrush(Color.FromRgb(0xff, 0xf3, 0xc4)),
                    null,
                    new Rect(chipX - cardH * 0.05, chipY, cardH * 0.10, cardH * 0.10),
                    cardH * 0.03, cardH * 0.03);
            }
        }
        return CreateFrame(visual, w, h, dpi);
    }
    private static VideoFrame GiftReceived(ChatMessage e, double t, int w, int h)
    {
        var dpi = 96.0;
        var visual = new DrawingVisual();
        using (var ctx = visual.RenderOpen())
        {
            var margin = Math.Max(w, h) * 0.04;
            var cardW = w - margin * 2;
            var cardH = h - margin * 2;
            var cardCX = w / 2.0;
            var enter = Clamp01(t / (EnterEnd * 1.4));
            var exit = Clamp01((t - ExitStart) / (1 - ExitStart));
            var scale = 0.5 + 0.5 * EaseOutBack(enter);
            var alpha = Math.Min(1.0, enter * 1.6) * (1 - exit);
            ctx.PushOpacity(alpha);
            ctx.PushTransform(new ScaleTransform(scale, scale, w / 2.0, h / 2.0));
            DrawCard(ctx, margin, margin, cardW, cardH, "#14532d", "#4c1d95", 18);
            DrawBrand(ctx, margin, margin, cardW, cardH);
            // Confetti falling inside the card during the hold (deterministic seed).
            if (t >= EnterEnd && t <= ExitStart)
            {
                var hold = (t - EnterEnd) / (ExitStart - EnterEnd);
                for (var i = 0; i < 14; i++)
                {
                    var seed = i * 37 + 11;
                    var dotX = margin + cardW * (((seed * 53) % 97) / 97.0);
                    var dotY = margin + cardH * (((seed + hold * 0.85) % 1.0));
                    var size = cardH * 0.02 + (i % 3) * cardH * 0.006;
                    ctx.DrawRectangle(
                        new SolidColorBrush(ConfettiPalette[i % ConfettiPalette.Length]),
                        null,
                        new Rect(dotX, dotY, size, size));
                }
            }
            DrawCentered(ctx, "GIFTED MEMBERSHIP", cardCX, margin + cardH * 0.22, cardH * 0.12, FontWeights.Bold, Color.FromRgb(0xff, 0xd1, 0x66), cardW * 0.9);
            var giver = string.IsNullOrWhiteSpace(e.GifterName) ? e.AuthorName : e.GifterName;
            DrawCentered(ctx, giver, cardCX, margin + cardH * 0.42, cardH * 0.20, FontWeights.Bold, White, cardW * 0.9);
            DrawCentered(ctx, "gave you a membership — celebrate!", cardCX, margin + cardH * 0.68, cardH * 0.11, FontWeights.Normal, Color.FromRgb(0xdb, 0xff, 0xf0), cardW * 0.9);
            ctx.Pop();
            ctx.Pop();
        }
        return CreateFrame(visual, w, h, dpi);
    }
    private static VideoFrame Milestone(ChatMessage e, double t, int w, int h)
    {
        var dpi = 96.0;
        var visual = new DrawingVisual();
        using (var ctx = visual.RenderOpen())
        {
            var margin = Math.Max(w, h) * 0.04;
            var cardW = w - margin * 2;
            var cardH = h - margin * 2;
            var cardCX = w / 2.0;
            var enter = Clamp01(t / EnterEnd);
            var exit = Clamp01((t - ExitStart) / (1 - ExitStart));
            var cardY = Lerp(h + cardH, margin, EaseOutCubic(enter));
            cardY = Lerp(cardY, -cardH, EaseInCubic(exit));
            DrawCard(ctx, margin, cardY, cardW, cardH, "#431407", "#c2410c", 14);
            DrawBrand(ctx, margin, cardY, cardW, cardH);
            var hero = e.MilestoneMonths > 0 ? $"{e.MilestoneMonths}" : "MILESTONE";
            DrawCentered(ctx, hero, cardCX, cardY + cardH * 0.26, cardH * 0.30, FontWeights.Bold, Color.FromRgb(0xff, 0xdd, 0x66), cardW * 0.8);
            var sub = e.MilestoneMonths > 0 ? "MONTHS STRONG" : "SUPPORTING THE STREAM";
            DrawCentered(ctx, sub, cardCX, cardY + cardH * 0.52, cardH * 0.11, FontWeights.SemiBold, White, cardW * 0.9);
            DrawCentered(ctx, "— " + e.AuthorName + " —", cardCX, cardY + cardH * 0.70, cardH * 0.10, FontWeights.Normal, Color.FromRgb(0xff, 0xe8, 0xd0), cardW * 0.9);
            // Tenure bar: grows through the first half, retracts on exit.
            var barP = Clamp01((t - 0.10) / 0.55) * (1 - exit);
            var barW = cardW * 0.6 * barP;
            ctx.DrawRoundedRectangle(
                new SolidColorBrush(Color.FromRgb(0xff, 0xd1, 0x66)),
                null,
                new Rect(cardCX - barW / 2, cardY + cardH * 0.84, barW, cardH * 0.045),
                4, 4);
        }
        return CreateFrame(visual, w, h, dpi);
    }
    // ─── Shared drawing ───
    private static void DrawCard(DrawingContext ctx, double x, double y, double w, double h, string fromHex, string toHex, double radius)
    {
        var brush = new LinearGradientBrush(ParseColor(fromHex), ParseColor(toHex), new Point(0, 0), new Point(1, 1));
        ctx.DrawRoundedRectangle(brush, new Pen(new SolidColorBrush(Color.FromArgb(0x66, 0xff, 0xff, 0xff)), Math.Max(1, radius * 0.06)), new Rect(x, y, w, h), radius, radius);
    }
    private static void DrawBrand(DrawingContext ctx, double x, double y, double w, double h)
    {
        var formatted = new FormattedText(
            Brand, Invariant, FlowDirection.LeftToRight,
            new Typeface(new FontFamily("Segoe UI"), FontStyles.Normal, FontWeights.Normal, FontStretches.Normal),
            Math.Max(9, h * 0.055),
            new SolidColorBrush(Color.FromArgb(0x88, 0xff, 0xff, 0xff)),
            96.0);
        ctx.DrawText(formatted, new Point(x + w - formatted.Width - h * 0.08, y + h - formatted.Height - h * 0.05));
    }
    private static void DrawCentered(DrawingContext ctx, string text, double cx, double cy, double size, FontWeight weight, Color color, double maxWidth)
    {
        var formatted = new FormattedText(
            text, Invariant, FlowDirection.LeftToRight,
            new Typeface(new FontFamily("Segoe UI"), FontStyles.Normal, weight, FontStretches.Normal),
            size,
            new SolidColorBrush(color),
            96.0);
        formatted.MaxTextWidth = maxWidth;
        formatted.MaxLineCount = 1;
        formatted.Trimming = TextTrimming.CharacterEllipsis;
        ctx.DrawText(formatted, new Point(cx - formatted.Width / 2, cy - formatted.Height / 2));
    }
    private static Color ParseColor(string hex)
    {
        hex = hex.Trim().TrimStart('#');
        if (hex.Length == 6)
        {
            var r = byte.Parse(hex.AsSpan(0, 2), NumberStyles.HexNumber);
            var g = byte.Parse(hex.AsSpan(2, 2), NumberStyles.HexNumber);
            var b = byte.Parse(hex.AsSpan(4, 2), NumberStyles.HexNumber);
            return Color.FromRgb(r, g, b);
        }
        if (hex.Length == 8)
        {
            var a = byte.Parse(hex.AsSpan(0, 2), NumberStyles.HexNumber);
            var r = byte.Parse(hex.AsSpan(2, 2), NumberStyles.HexNumber);
            var g = byte.Parse(hex.AsSpan(4, 2), NumberStyles.HexNumber);
            var b = byte.Parse(hex.AsSpan(6, 2), NumberStyles.HexNumber);
            return Color.FromArgb(a, r, g, b);
        }
        return Colors.White;
    }
    private static VideoFrame CreateFrame(DrawingVisual visual, int width, int height, double dpi)
    {
        var rtb = new RenderTargetBitmap(width, height, dpi, dpi, PixelFormats.Pbgra32);
        rtb.Render(visual);
        var stride = width * 4;
        var pixels = new byte[stride * height];
        rtb.CopyPixels(pixels, stride, 0);
        for (var i = 0; i < pixels.Length; i += 4)
        {
            (pixels[i], pixels[i + 2]) = (pixels[i + 2], pixels[i]);
        }
        return new VideoFrame(width, height, pixels);
    }
    private static double Clamp01(double v) => Math.Clamp(v, 0.0, 1.0);
    private static double Lerp(double a, double b, double p) => a + (b - a) * p;
    private static double EaseInCubic(double p) => p * p * p;
    private static double EaseOutCubic(double p) => 1 - Math.Pow(1 - p, 3);
    private static double EaseOutBack(double p)
    {
        const double c1 = 1.70158;
        const double c3 = c1 + 1;
        return 1 + c3 * Math.Pow(p - 1, 3) + c1 * Math.Pow(p - 1, 2);
    }
 }
@@ -28,8 +28,12 @@ public sealed class AudioGainProvider
    /// <summary>Mic gain for the live mix (0 = muted).</summary>
    public double MicGain() => _micMuted() ? 0 : _micVolume();
-    /// <summary>Loopback (desktop/game) gain for the live mix (0 = muted, 1 = unity).
+    /// <summary>Loopback (desktop/game) gain for the live mix (0 = muted).
-    /// Unity because the slider now drives system volume via PushSystemVolume,
+    /// Honesty rule (2026-09-01): WASAPI loopback capture does NOT shrink with the
-    /// so the WASAPI loopback signal is already scaled by the user's volume choice.</summary>
+    /// endpoint volume — the creator dropped system volume to 20% and the captured
-    public double LoopbackGain() => _gameMuted() ? 0 : 1.0;
+    /// level stayed pegged — so the mixer must multiply by GameAudioVolume itself
    /// for the stream to follow the knob (the old unity assumption left the stream
    /// at full desktop volume while the headphones went quiet; ai.md always
    /// specified loopbackGain = GameAudioVolume — the code had drifted).</summary>
    public double LoopbackGain() => _gameMuted() ? 0 : _gameVolume();
 }
@@ -1,3 +1,4 @@
 using ytLive.Helpers;
 using ytLive.Services;
 namespace ytLive.Services.Audio;
@@ -13,7 +14,9 @@ namespace ytLive.Services.Audio;
 /// queues, applies the honest gains (mic = MicVolume, loopback = unity
 /// × auto-duck when the mic is hot — the slider drives system volume via mixes them to stereo float, runs the
 /// master limiter (a -1 dBFS ceiling so the sum never clips the encoder), and
-/// writes the chunk to the encoder's audio pipe.
+/// writes the chunk to the encoder's audio pipe. Since TASK 47 the alert layer's
 /// clip audio joins the same mix (pre-scaled, unity-added, never ducked) through
 /// <see cref="EnqueueAlertAudio"/>.
 /// </summary>
 public sealed class AudioMixer : IDisposable
 {
@@ -29,12 +32,16 @@ public sealed class AudioMixer : IDisposable
    private readonly Func<double>? _micGain;
    private readonly Func<double>? _loopbackGain;
    private readonly TimeSpan _mixInterval;
    private readonly Func<int>? _syncOffsetMs;
    private readonly AudioSyncDelay _syncDelay;
    private int _advanceSamplesRemaining;
    private bool _started;
    // Live path (TASK 9): per-source resampling → voice chain on the mic →
    // thread-safe queues → the ducker + gain/mix loop → the encoder's pipe.
    private readonly AudioRingBuffer _micBuffer;
    private readonly AudioRingBuffer _loopbackBuffer;
    private readonly AudioRingBuffer _alertBuffer;
    private readonly VoiceFilterChain _voiceChain;
    private readonly AutoDucker _ducker;
    private readonly MasterLimiter _masterLimiter = new();
@@ -44,7 +51,14 @@ public sealed class AudioMixer : IDisposable
    private NamedPipeAudioWriter _pipe = new();
    private float[]? _micChunk;
    private float[]? _loopbackChunk;
    private float[]? _alertChunk;
    private float[]? _mixBuffer;
    private float[]? _delayedMix;
    private DateTime _lastLoopErrorLogged = DateTime.MinValue;
    private DateTime _nextStatsLog = DateTime.UtcNow + TimeSpan.FromSeconds(5);
    private long _micDrainedTotal;
    private long _loopDrainedTotal;
    private float _peakMix;
    public AudioMixer(
        IAudioSource mic,
@@ -52,6 +66,7 @@ public sealed class AudioMixer : IDisposable
        Action<string>? log = null,
        Func<double>? micGain = null,
        Func<double>? loopbackGain = null,
        Func<int>? syncOffsetMs = null,
        TimeSpan? mixInterval = null)
    {
        _mic = mic;
@@ -61,17 +76,22 @@ public sealed class AudioMixer : IDisposable
        _log = log;
        _micGain = micGain;
        _loopbackGain = loopbackGain;
        _syncOffsetMs = syncOffsetMs;
        _syncDelay = new AudioSyncDelay(OutputSampleRate);
        _mixInterval = mixInterval ?? DefaultMixInterval;
        var seconds = _mixInterval.TotalSeconds;
        var framesPerTick = Math.Max(1, (int)Math.Round(OutputSampleRate * seconds));
        _micBuffer = new AudioRingBuffer(OutputSampleRate * 2);
        _loopbackBuffer = new AudioRingBuffer(OutputSampleRate * 2 * 2);
        _alertBuffer = new AudioRingBuffer(OutputSampleRate * 2 * 8);
        _voiceChain = new VoiceFilterChain(OutputSampleRate);
        _ducker = new AutoDucker();
        _micChunk = new float[framesPerTick];
        _loopbackChunk = new float[framesPerTick * 2];
        _alertChunk = new float[framesPerTick * 2];
        _mixBuffer = new float[framesPerTick * 2];
        _delayedMix = new float[framesPerTick * 2];
        _mic.Started += OnMicStarted;
        _mic.SampleReady += OnMicSample;
@@ -146,19 +166,48 @@ public sealed class AudioMixer : IDisposable
        if (_liveCts != null)
            return;
        // Capture runs from app STARTUP for the meters, so both rings carry up
        // to a full ring depth (~2s) of pre-live backlog by the time the user
        // hits record; draining it made every recorded event land ~2s late in
        // the audio track (2026-09-14, two confirmed takes). Discard it so the
        // recording starts at go-live. The writers keep running concurrently;
        // Clear under the ring's lock, so only the in-flight chunk is dropped.
        _micBuffer.Clear();
        _loopbackBuffer.Clear();
        _alertBuffer.Clear();
        // Negative sync offset (audio runs BEHIND video): OBS's fix is to "eat
        // the head of the buffer" — discard the first |N| ms of the live stream
        // so every subsequent audio event lands |N| ms EARLIER in the recording.
        // Armed once at go-live (you can't eat the head mid-stream); positive
        // offsets stay live-reactive through the delay line in FillAndMix.
        var syncMs = _syncOffsetMs?.Invoke() ?? 0;
        _advanceSamplesRemaining = syncMs < 0
            ? (int)Math.Round(OutputSampleRate / 1000.0 * -syncMs) * 2
            : 0;
        if (_advanceSamplesRemaining > 0)
            _log?.Invoke($"Audio live: advance armed ({-syncMs} ms ahead)");
        var cts = new CancellationTokenSource();
        _liveCts = cts;
        _pipe = new NamedPipeAudioWriter();
        _pipe.Start(pipeName);
        _log?.Invoke($"Audio live: started, pipe '{pipeName}'");
        _ = Task.Run(() => LiveLoopAsync(_pipe, cts.Token));
    }
    /// <summary>Ends the live mix loop and closes the audio pipe — ffmpeg sees
-    /// EOF on the audio input. Safe when not live.</summary>
+    /// EOF on the audio input. Safe when not live: the writer's Stop() is idempotent
    /// (StopStream now calls this on every rollback path).</summary>
    public void StopLive()
    {
-        _liveCts?.Cancel();
+        var cts = _liveCts;
        _liveCts = null;
        if (cts != null)
        {
            _log?.Invoke("Audio live: stopped");
            cts.Cancel();
        }
        _pipe.Stop();
    }
@@ -204,6 +253,34 @@ public sealed class AudioMixer : IDisposable
        LoopbackLevelChanged?.Invoke(level);
    }
    /// <summary>Drops the alert clip's audio into its own ring (TASK 47 — the
    /// stream-alert video's soundtrack, pre-scaled by the alert layer to
    /// volume × fade). Mixed at unity into the live output — NO auto-duck: an
    /// alert must be heard over the mic, so the Creator's per-alert volume
    /// slider is the honest gain and nothing else is stacked on top. Monno and
    /// non-48k sources are normalized (the decoder already emits 48k stereo).</summary>
    public void EnqueueAlertAudio(AudioSample sample)
    {
        var data = sample.Samples;
        if (data.Length == 0) return;
        if (sample.SampleRate != OutputSampleRate)
            data = ResampleLoopback(data, sample.SampleRate);
        if (sample.Channels == 1)
            data = UpmixToStereo(data);
        _alertBuffer.Write(data);
    }
    private static float[] UpmixToStereo(float[] mono)
    {
        var stereo = new float[mono.Length * 2];
        for (var i = 0; i < mono.Length; i++)
        {
            stereo[i * 2] = mono[i];
            stereo[i * 2 + 1] = mono[i];
        }
        return stereo;
    }
    private void OnMicFailed(Exception ex)
    {
        _log?.Invoke($"Mic capture failed: {ex.Message}");
@@ -263,8 +340,42 @@ public sealed class AudioMixer : IDisposable
            var nextTick = DateTime.UtcNow + _mixInterval;
            try
            {
-                FillAndMix(micChunk, loopbackChunk, mixBuffer);
+                var (_, micDrained, loopDrained) = FillAndMix(micChunk, loopbackChunk, mixBuffer);
-                await pipe.WriteAsync(mixBuffer, cancellationToken).ConfigureAwait(false);
+
                // Negative offset: skip the armed |N| ms of stream head. The pipe
                // writer tolerates a partial chunk (any float length is valid);
                // dropping the head re-anchors the audio stream against the video
                // stream, making each event land earlier — OBS's eat-the-head fix.
                var writeFrom = 0;
                if (_advanceSamplesRemaining > 0)
                {
                    var drop = Math.Min(_advanceSamplesRemaining, mixBuffer.Length);
                    _advanceSamplesRemaining -= drop;
                    writeFrom = drop;
                }
                if (writeFrom < mixBuffer.Length)
                    await pipe.WriteAsync(mixBuffer.AsMemory(writeFrom), cancellationToken).ConfigureAwait(false);
                _micDrainedTotal += micDrained;
                _loopDrainedTotal += loopDrained;
                for (var i = writeFrom; i < mixBuffer.Length; i++)
                {
                    var abs = Math.Abs(mixBuffer[i]);
                    if (abs > _peakMix) _peakMix = abs;
                }
                var now = DateTime.UtcNow;
                if (now >= _nextStatsLog && _log != null)
                {
                    _nextStatsLog = now + TimeSpan.FromSeconds(5);
                    _log($"Audio live: pipe connected={pipe.IsConnected} dropped writes={pipe.DroppedWrites} " +
                         $"micLevel={_meter.Level:F3} loopLevel={_loopbackMeter.Level:F3} " +
                         $"drained {_micDrainedTotal:N0}/{_loopDrainedTotal:N0} samples peakMix {_peakMix:F3} (per 5s)");
                    _micDrainedTotal = 0;
                    _loopDrainedTotal = 0;
                    _peakMix = 0;
                }
            }
            catch (OperationCanceledException)
            {
@@ -272,7 +383,18 @@ public sealed class AudioMixer : IDisposable
            }
            catch (Exception ex)
            {
-                _log?.Invoke($"Audio live loop error: {ex.Message}");
+                // Throttled + never on a dead session: the 2026-09-01 first-launch flood
                // was one logged NRE every 10ms tick (see _delayedMix fix). Log at most
                // once per 5s, and stop looping if the pipe writer is gone for good.
                if (cancellationToken.IsCancellationRequested)
                    break;
                var now = DateTime.UtcNow;
                if (now - _lastLoopErrorLogged >= TimeSpan.FromSeconds(5))
                {
                    _lastLoopErrorLogged = now;
                    AppLog.Write(ex, "Audio live loop error");
                    _log?.Invoke($"Audio live loop error: {ex.Message}");
                }
            }
            var delay = nextTick - DateTime.UtcNow;
@@ -291,11 +413,16 @@ public sealed class AudioMixer : IDisposable
    }
    /// <summary>Drains one tick's worth of mic + loopback, silence-fills any
-    /// underrun, applies the ducker and the honest gains, and mixes to stereo.</summary>
+    /// underrun, applies the ducker and the honest gains, and mixes to stereo.
-    private float FillAndMix(float[] micChunk, float[] loopbackChunk, float[] mix)
+    /// Returns the pre-duck mic RMS and how many samples each buffer contributed
    /// (the 5s live-loop telemetry reads those to name whether capture or the
    /// pipe starved a silent recording).</summary>
    private (float MicRms, int MicDrained, int LoopDrained) FillAndMix(float[] micChunk, float[] loopbackChunk, float[] mix)
    {
        var micCount = _micBuffer.Read(micChunk, micChunk.Length);
        var loopCount = _loopbackBuffer.Read(loopbackChunk, loopbackChunk.Length);
        var alertChunk = _alertChunk!;
        var alertCount = _alertBuffer.Read(alertChunk, alertChunk.Length);
        float micRms = 0;
        if (micCount == 0)
@@ -321,6 +448,15 @@ public sealed class AudioMixer : IDisposable
            Array.Clear(loopbackChunk, loopCount, loopbackChunk.Length - loopCount);
        }
        if (alertCount == 0)
        {
            Array.Clear(alertChunk, 0, alertChunk.Length);
        }
        else if (alertCount < alertChunk.Length)
        {
            Array.Clear(alertChunk, alertCount, alertChunk.Length - alertCount);
        }
        var duck = _ducker.Update(micRms);
        var micGain = (float)(_micGain?.Invoke() ?? 1.0);
        var loopGain = (float)(_loopbackGain?.Invoke() ?? 1.0) * duck;
@@ -329,10 +465,17 @@ public sealed class AudioMixer : IDisposable
        for (var i = 0; i < frames; i++)
        {
            var m = micChunk[i] * micGain;
-            mix[i * 2] = m + loopbackChunk[i * 2] * loopGain;
+            mix[i * 2] = m + loopbackChunk[i * 2] * loopGain + alertChunk[i * 2];
-            mix[i * 2 + 1] = m + loopbackChunk[i * 2 + 1] * loopGain;
+            mix[i * 2 + 1] = m + loopbackChunk[i * 2 + 1] * loopGain + alertChunk[i * 2 + 1];
        }
        _masterLimiter.Process(mix);
-        return micRms;
+
        _syncDelay.Configure(_syncOffsetMs?.Invoke() ?? 0);
        var delayed = _delayedMix;
        if (delayed is null || delayed.Length < mix.Length)
            delayed = _delayedMix = new float[mix.Length];
        _syncDelay.Process(mix, delayed);
        Array.Copy(delayed, mix, mix.Length);
        return (micRms, micCount, loopCount);
    }
 }
@@ -0,0 +1,94 @@
 using System;
 namespace ytLive.Services.Audio;
 /// <summary>
 /// TASK 22: a fixed end-to-end audio delay applied to the interleaved stereo
 /// mix in <see cref="AudioMixer"/>. This is OBS's documented fix for the
 /// "audio is ahead of video" lip-sync case: delay the audio by a few
 /// milliseconds so it lands on the video. It is a pure delay line — input in,
 /// the same audio N ms later out — so it is trivially testable and carries no
 /// state outside its own ring.
 ///
 /// Positive offsets only (0..500 ms). Advancing audio (the audio runs BEHIND
 /// the video) is handled upstream in <see cref="AudioMixer"/>, not here: the
 /// mixer eats the first |N| ms of the live stream head (OBS's negative sync —
 /// see <see cref="AudioMixer.StartLive"/>), keeping this line a pure delay.
 /// Changing the delay flushes the line, so a live slider change clicks rather
 /// than smearing. Safe to call from any thread — the mixer owns it.
 /// </summary>
 public sealed class AudioSyncDelay
 {
    private readonly int _sampleRate;
    private float[] _buffer = Array.Empty<float>();
    private int _delaySamples;
    private int _writePos;
    public AudioSyncDelay(int sampleRate)
    {
        _sampleRate = Math.Max(1, sampleRate);
        Configure(0);
    }
    /// <summary>Sets the delay in whole milliseconds (clamped to 0..500). A no-op
    /// when the delay hasn't actually changed — <see cref="AudioMixer.FillAndMix"/>
    /// calls this every ~10ms tick (it re-reads the live UI setting each mix), and
    /// unconditionally reallocating+zeroing the line every tick (the 2026-09-12
    /// total-silence bug: any non-zero saved offset wiped the ring before its own
    /// delayed samples could ever be read back — mic/loop meters, sampled BEFORE
    /// this stage, kept showing real levels while the pipe stayed pure silence)
    /// discarded the entire buffered history every 10ms. Changing the delay still
    /// flushes the line (a live slider change clicks rather than smearing).</summary>
    public void Configure(int delayMs)
    {
        var delaySamples = Frames(delayMs);
        if (delaySamples == _delaySamples && _buffer.Length > 0) return;
        _delaySamples = delaySamples;
        _buffer = new float[(_delaySamples + _sampleRate) * 2 + 1024];
        _writePos = 0;
    }
    /// <summary>Delays an interleaved stereo chunk by the configured offset.
    /// The returned length equals <paramref name="input"/>'s; the head is
    /// silence until the line fills.</summary>
    public void Process(ReadOnlySpan<float> input, Span<float> output)
    {
        if (output.Length < input.Length)
            throw new ArgumentException("output must be at least as long as input", nameof(output));
        var len = input.Length;
        if (_delaySamples == 0)
        {
            input.CopyTo(output);
            return;
        }
        var line = _buffer;
        var lineLen = line.Length;
        for (var i = 0; i < len; i++)
        {
            line[_writePos] = input[i];
            _writePos++;
            if (_writePos == lineLen)
                _writePos = 0;
        }
        var readStart = (_writePos - _delaySamples - len + lineLen * 2) % lineLen;
        for (var i = 0; i < len; i++)
        {
            var idx = readStart + i;
            if (idx >= lineLen)
                idx -= lineLen;
            output[i] = line[idx];
        }
    }
    private int Frames(int delayMs)
    {
        var clamped = Math.Clamp(delayMs, 0, 500);
        // Interleaved stereo: each frame is two samples (L, R), so the delay
        // in buffer positions is twice the frame count.
        return (int)Math.Round(_sampleRate / 1000.0 * clamped) * 2;
    }
 }
@@ -17,6 +17,12 @@ public interface IAudioPipeWriter : IDisposable
    /// <summary>True once ffmpeg has connected and the pipe is writable.</summary>
    bool IsConnected { get; }
    /// <summary>Count of <see cref="WriteAsync"/> calls that wrote nothing because
    /// the pipe wasn't connected yet or was already closed. Part of the silent-
    /// recording diagnosis: nonzero means audio was dropped before ffmpeg ever
    /// connected to the pipe.</summary>
    long DroppedWrites { get; }
    /// <summary>Writes interleaved float samples; dropped until the client connects.</summary>
    Task WriteAsync(ReadOnlyMemory<float> samples, CancellationToken cancellationToken = default);
@@ -29,6 +35,9 @@ public sealed class NamedPipeAudioWriter : IAudioPipeWriter
    private readonly object _sync = new();
    private NamedPipeServerStream? _pipe;
    /// <inheritdoc/>
    public long DroppedWrites { get; private set; }
    public void Start(string pipeName)
    {
        lock (_sync)
@@ -64,7 +73,11 @@ public sealed class NamedPipeAudioWriter : IAudioPipeWriter
            pipe = _pipe;
        }
        if (pipe == null || !pipe.IsConnected || samples.IsEmpty)
        {
            if (pipe?.IsConnected == false || pipe == null)
                DroppedWrites++;
            return;
        }
        var bytes = MemoryMarshal.AsBytes(samples.Span).ToArray();
        await pipe.WriteAsync(bytes, cancellationToken).ConfigureAwait(false);
@@ -171,6 +171,18 @@ public sealed class CameraManager : IDisposable
        toStop.PreviewBitmap = null;
    }
    /// <summary>
    /// True while a session exists for the device — started, or still starting.
    /// Used by the app's startup resource check to avoid double-acquiring a lock
    /// that the saved identity's scene configs already hold. A rolled-back (failed)
    /// session is removed, so this goes false and the startup pass can retry.
    /// </summary>
    public bool IsRunning(string deviceId)
    {
        lock (_gate)
            return _sessions.ContainsKey(deviceId);
    }
    public VideoFrame? GetLatestFrame(string deviceId)
    {
        lock (_gate)
@@ -0,0 +1,132 @@
 using System.Net.Http;
 using System.Text.Json;
 using ytLive.Models;
 using AppLog = ytLive.Helpers.AppLog;
 namespace ytLive.Services;
 /// <summary>
 /// Pulls a connected channel's YPP-relevant numbers from the YouTube Data API
 /// (TASK 39, slice 1): subscriptions/views/videos via channels.list, and the
 /// count of public uploads in the trailing 90 days via playlistItems.list on the
 /// uploads playlist. Long-form watch hours and Shorts-feed views need the
 /// Analytics API (a later slice behind the IChannelStatsProvider seam).
 ///
 /// NOTE (root cause, 2026-09-23): channels.list must NOT request the
 /// `auditDetails` part — that part alone requires the
 /// `youtubepartner-channel-audit` scope the app doesn't (and mustn't) hold, and
 /// the whole request 403s `insufficientPermissions` over it. Standing flags are
 /// not exposed to ordinary apps; the drawer deep-links to YouTube Studio instead.
 /// </summary>
 public class ChannelStatsService
 {
    private readonly YouTubeAuthService _auth;
    private readonly HttpClient _http;
    private const string ApiBase = "https://www.googleapis.com/youtube/v3";
    public ChannelStatsService(YouTubeAuthService auth, HttpClient? http = null)
    {
        _auth = auth;
        _http = http ?? new HttpClient();
    }
    private async Task<bool> EnsureToken()
    {
        if (_auth.CurrentChannel == null) return false;
        if (_auth.CurrentChannel.TokenExpiry <= DateTime.UtcNow.AddMinutes(5))
            return await _auth.RefreshToken();
        return true;
    }
    /// <summary>Captures the channel's current stats into a snapshot, or null when
    /// there's no session, a request fails, or the API returns nothing. Never throws.</summary>
    public virtual async Task<YppStatSnapshot?> CaptureCurrentAsync()
    {
        if (!await EnsureToken()) return null;
        _http.DefaultRequestHeaders.Authorization = new("Bearer", _auth.CurrentChannel!.AccessToken);
        var response = await _http.GetAsync(
            $"{ApiBase}/channels?mine=true&part=statistics,contentDetails");
        if (!response.IsSuccessStatusCode)
        {
            // Log the response body: YouTube's error.reason names the failure
            // (insufficientPermissions / quotaExceeded / …) — the bare code was
            // undiagnosable for the 2026-09-23 auditDetails 403.
            var errorBody = await response.Content.ReadAsStringAsync();
            AppLog.Write($"YPP stats: channels.list failed ({(int)response.StatusCode}): {errorBody}");
            return null;
        }
        var json = JsonSerializer.Deserialize<JsonElement>(await response.Content.ReadAsStringAsync());
        if (!json.TryGetProperty("items", out var items) || items.GetArrayLength() == 0)
            return null;
        var channel = items[0];
        var statistics = channel.GetProperty("statistics");
        var uploadsPlaylistId = channel.TryGetProperty("contentDetails", out var contentDetails)
            && contentDetails.TryGetProperty("relatedPlaylists", out var related)
            && related.TryGetProperty("uploads", out var uploads)
            ? uploads.GetString()
            : null;
        var uploadsLast90Days = uploadsPlaylistId != null
            ? await CountUploadsLast90DaysAsync(uploadsPlaylistId)
            : 0;
        return new YppStatSnapshot
        {
            CapturedAtUtc = DateTime.UtcNow,
            SubscriberCount = ReadInt64(statistics, "subscriberCount"),
            VideoCount = ReadInt64(statistics, "videoCount"),
            TotalViews = ReadInt64(statistics, "viewCount"),
            UploadsLast90Days = uploadsLast90Days,
        };
    }
    /// <summary>YouTube serializes statistics as JSON STRINGS ("350"); a tolerant
    /// read that also accepts a number (the real 403 hid this parse bug until the
    /// auditDetails removal surfaced the string shape in 2026-09-23's Good Dog).
    /// NOTE: JsonElement.TryGetInt64 THROWS on a non-Number token — ValueKind must
    /// be checked first (try-type-in, not try-catch).</summary>
    private static long ReadInt64(JsonElement parent, string name)
    {
        if (!parent.TryGetProperty(name, out var value)) return 0;
        if (value.ValueKind == JsonValueKind.Number && value.TryGetInt64(out var n)) return n;
        if (value.ValueKind == JsonValueKind.String && long.TryParse(value.GetString(), out n)) return n;
        return 0;
    }
    /// <summary>Counts uploads published within the trailing 90 days, scanning the
    /// most recent 50 from the uploads playlist (generous beyond the 3/90-day YPP
    /// requirement; the YPP tab labels it as the recent-50 window).</summary>
    private async Task<int> CountUploadsLast90DaysAsync(string uploadsPlaylistId)
    {
        var response = await _http.GetAsync(
            $"{ApiBase}/playlistItems?part=snippet&playlistId={Uri.EscapeDataString(uploadsPlaylistId)}&maxResults=50");
        if (!response.IsSuccessStatusCode)
        {
            AppLog.Write($"YPP stats: playlistItems.list failed ({(int)response.StatusCode})");
            return 0;
        }
        var json = JsonSerializer.Deserialize<JsonElement>(await response.Content.ReadAsStringAsync());
        if (!json.TryGetProperty("items", out var items)) return 0;
        var cutoff = DateTime.UtcNow.AddDays(-90);
        var count = 0;
        foreach (var item in items.EnumerateArray())
        {
            if (!item.TryGetProperty("snippet", out var snippet)
                || !snippet.TryGetProperty("publishedAt", out var published)
                || !DateTime.TryParse(published.GetString(), out var publishedAt))
            {
                continue;
            }
            if (publishedAt.ToUniversalTime() >= cutoff)
                count++;
        }
        return count;
    }
 }
@@ -0,0 +1,249 @@
 using System.Collections.ObjectModel;
 using System.Linq;
 using System.Windows;
 using System.Windows.Media;
 using System.Windows.Media.Imaging;
 using System.Windows.Threading;
 using ytLive.Helpers;
 using ytLive.Models;
 namespace ytLive.Services;
 /// <summary>Owns the YouTube-chat overlay behavior: the message buffer, the
 /// renderer, and the fade/mock-preview timers. The MainViewModel keeps only the
 /// thin binding surface (the shared <see cref="Messages"/> collection + two
 /// computed gate props) and hands the scene list in at each call — this class
 /// owns all chat logic so an AI can read one self-contained unit.</summary>
 public sealed class ChatOverlayLayer
 {
    private readonly ChatBoxRenderer _renderer;
    // Mock chat messages for the ChatBox preview — branded placeholders so the
    // creator sees where the overlay lands before going live.
    private static readonly IReadOnlyList<ChatMessage> MockChatMessages = new[]
    {
        new ChatMessage { AuthorName = "LlamaCasty", Message = "welcome to the stream!", Timestamp = DateTime.Now.AddMinutes(-4), IsMember = true },
        new ChatMessage { AuthorName = "LlamaCastyFan", Message = "$10 — LlamaCasty is the best!", Timestamp = DateTime.Now.AddMinutes(-3), IsSuperChat = true },
        new ChatMessage { AuthorName = "GamerDude", Message = "what streaming software is this?", Timestamp = DateTime.Now.AddMinutes(-2) },
        new ChatMessage { AuthorName = "LlamaCasty", Message = "thanks for watching! llamacasty.com", Timestamp = DateTime.Now.AddMinutes(-1), IsMember = true },
        new ChatMessage { AuthorName = "LlamaDog", Message = "Subscribe so they can buy the subscription at llamacasty.com!", Timestamp = DateTime.Now, IsMember = true },
    };
    // Chat fade timer: clears chat overlay after N seconds of inactivity.
    private DispatcherTimer? _fadeTimer;
    private CancellationTokenSource? _mockCts;
    /// <summary>The live chat message buffer. Shared with the ViewModel (which
    /// binds it to the panel) via <c>ChatMessages =&gt; _chatLayer.Messages</c>.</summary>
    public ObservableCollection<ChatMessage> Messages { get; } = new();
    // Output-frame cache (take-5 starvation fix): the pump called RenderFrame
    // every tick and the renderer did a FULL WPF raster (FormattedText +
    // RenderTargetBitmap + CopyPixels + channel swap) each time — 15-25ms of a
    // 25.5ms render. Established answer (OBS text sources): raster on change,
    // blit the cache every tick. _contentVersion bumps on every buffer mutation
    // (CollectionChanged — covers adds, the 500-cap removal, and the fade
    // Clear from any caller); the config key covers the box geometry/appearance.
    // The cached VideoFrame is treated as immutable: the compositor only reads.
    private int _contentVersion;
    private int _frameVersion = -1;
    private string? _frameKey;
    private VideoFrame? _cachedFrame;
    public ChatOverlayLayer(ChatBoxRenderer renderer)
    {
        _renderer = renderer;
        Messages.CollectionChanged += (_, _) => _contentVersion++;
    }
    /// <summary>Ingest a message from the poller. UI-thread marshalled: appended
    /// to the buffer (capped at 500), mock preview stopped, swipe to real
    /// messages, and the fade timer reset. Scenes are handed in so the layer can
    /// refresh every ChatBox preview without owning the scene graph.</summary>
    public void OnMessageReceived(ChatMessage message, IEnumerable<Scene> scenes)
    {
        System.Windows.Application.Current.Dispatcher.Invoke(() =>
        {
            Messages.Add(message);
            if (Messages.Count > 500)
                Messages.RemoveAt(0);
            // Reset chat fade timer on every message
            ResetChatFadeTimer(scenes);
            StopMockPreview();
            // Switch ChatBox previews from mock to real messages
            foreach (var chatBox in scenes.SelectMany(s => s.Elements).OfType<Source>()
                         .Where(s => s.Type == SourceType.ChatBox))
                UpdatePreview(chatBox);
        });
    }
    private void ResetChatFadeTimer(IEnumerable<Scene> scenes)
    {
        _fadeTimer?.Stop();
        var chatBoxes = scenes.SelectMany(s => s.Elements).OfType<Source>()
            .Where(s => s.Type == SourceType.ChatBox && s.ChatFadeSeconds > 0).ToList();
        if (chatBoxes.Count == 0) return;
        var delay = chatBoxes.Min(s => s.ChatFadeSeconds);
        _fadeTimer = new DispatcherTimer { Interval = TimeSpan.FromSeconds(delay) };
        _fadeTimer.Tick += (_, _) =>
        {
            _fadeTimer?.Stop();
            _fadeTimer = null;
            Messages.Clear();
            foreach (var chatBox in scenes.SelectMany(s => s.Elements).OfType<Source>()
                         .Where(s => s.Type == SourceType.ChatBox))
                UpdatePreview(chatBox);
            StartMockPreview(scenes);
        };
        _fadeTimer.Start();
    }
    /// <summary>Renders the live-output frame for one ChatBox element (the
    /// compositor path), or null when no messages are buffered yet. Mirrors the
    /// preview render but without writing onto the source's VideoImageSource.</summary>
    public VideoFrame? RenderFrame(Source chatBox)
    {
        var width = (int)Math.Max(1, chatBox.Width);
        var height = (int)Math.Max(1, chatBox.Height);
        var key =
            $"{width}x{height}|{chatBox.ChatFontSize}|{chatBox.ChatFontFamily}|{chatBox.ChatFontColor}"
            + $"|{chatBox.ChatBackgroundColor}|{chatBox.ChatMaxMessages}|{chatBox.ChatShowTimestamps}"
            + $"|{chatBox.ChatShowBadges}|{chatBox.ChatMemberColor}|{chatBox.ChatSuperChatColor}";
        if (_frameKey == key && _frameVersion == _contentVersion)
            return _cachedFrame; // same content + same config — the cached raster stands
        // The raster is WPF (DrawingVisual + RenderTargetBitmap = UI-thread objects)
        // and the frame pump now renders from its own thread (take-8 off-UI fix) —
        // so only the cache CHECK runs off-thread; the rare miss marshals to the
        // dispatcher and re-validates there (a second message landing mid-hop must
        // not be answered by a snapshot taken before it).
        var app = System.Windows.Application.Current;
        if (app != null && !app.Dispatcher.CheckAccess())
        {
            var capturedKey = key;
            var capturedVersion = _contentVersion;
            var frame = app.Dispatcher.Invoke(() =>
            {
                if (_frameKey == capturedKey && _frameVersion == capturedVersion)
                    return _cachedFrame; // someone already re-rasterized on the UI thread
                return RenderCore(chatBox, width, height, capturedKey, capturedVersion);
            });
            return frame;
        }
        return RenderCore(chatBox, width, height, key, _contentVersion);
    }
    private VideoFrame? RenderCore(Source chatBox, int width, int height, string key, int version)
    {
        _frameKey = key;
        _frameVersion = version;
        if (Messages.Count == 0) return _cachedFrame = null;
        return _cachedFrame = _renderer.Render(
            Messages,
            width,
            height,
            chatBox.ChatFontSize,
            chatBox.ChatFontFamily,
            chatBox.ChatFontColor,
            chatBox.ChatBackgroundColor,
            chatBox.ChatMaxMessages,
            chatBox.ChatShowTimestamps,
            chatBox.ChatShowBadges,
            chatBox.ChatMemberColor,
            chatBox.ChatSuperChatColor);
    }
    /// <summary>Renders one ChatBox preview: real messages when connected, mock
    /// when not. Writes the resulting bitmap onto the source's
    /// <c>VideoImageSource</c>.</summary>
    public void UpdatePreview(Source chatBox, IReadOnlyList<ChatMessage>? messages = null)
    {
        try
        {
            messages ??= Messages.Count > 0 ? (IReadOnlyList<ChatMessage>)Messages : MockChatMessages;
            var width = (int)Math.Max(32, chatBox.Width);
            var height = (int)Math.Max(32, chatBox.Height);
            var frame = _renderer.Render(
                messages,
                width,
                height,
                chatBox.ChatFontSize,
                chatBox.ChatFontFamily,
                chatBox.ChatFontColor,
                chatBox.ChatBackgroundColor,
                chatBox.ChatMaxMessages,
                chatBox.ChatShowTimestamps,
                chatBox.ChatShowBadges,
                chatBox.ChatMemberColor,
                chatBox.ChatSuperChatColor);
            var bitmap = new WriteableBitmap(width, height, 96, 96, PixelFormats.Bgra32, null);
            bitmap.WritePixels(new Int32Rect(0, 0, width, height), frame.BgraPixels, frame.Stride, 0);
            chatBox.VideoImageSource = bitmap;
        }
        catch (Exception ex) { AppLog.Write($"UpdateChatBoxPreview failed: {ex.Message}"); }
    }
    private async Task RunMockPreviewAsync(Source chatBox, CancellationToken ct)
    {
        var n = 0;
        while (!ct.IsCancellationRequested)
        {
            UpdatePreview(chatBox, MockChatMessages.Take(n + 1).ToList());
            await Task.Delay(1000, ct);
            n++;
            if (n == MockChatMessages.Count)
            {
                await Task.Delay(3000, ct);
                n = 0;
            }
        }
    }
    public void StartMockPreview(IEnumerable<Scene> scenes)
    {
        StopMockPreview();
        _mockCts = new CancellationTokenSource();
        var ct = _mockCts.Token;
        foreach (var chatBox in scenes.SelectMany(s => s.Elements).OfType<Source>()
                     .Where(s => s.Type == SourceType.ChatBox && s.ChatPreviewEnabled))
            _ = RunMockPreviewAsync(chatBox, ct);
    }
    public void StopMockPreview()
    {
        _mockCts?.Cancel();
        _mockCts?.Dispose();
        _mockCts = null;
    }
    /// <summary>Render previews + wire property-change subscriptions for all
    /// ChatBox sources across every scene. Called after layout load so existing
    /// ChatBox sources show mock content and respond to config changes.</summary>
    public void UpdateConfiguredBoxes(IEnumerable<Scene> scenes)
    {
        foreach (var scene in scenes)
            foreach (var chatBox in scene.Elements.OfType<Source>().Where(s => s.Type == SourceType.ChatBox))
            {
                chatBox.PropertyChanged += (_, e) =>
                {
                    if (e.PropertyName is nameof(Source.ChatFontSize) or nameof(Source.ChatFontColor)
                        or nameof(Source.ChatBackgroundColor) or nameof(Source.ChatBackgroundOpacity)
                        or nameof(Source.ChatMaxMessages) or nameof(Source.ChatShowTimestamps)
                        or nameof(Source.ChatShowBadges) or nameof(Source.ChatMemberColor)
                        or nameof(Source.ChatSuperChatColor) or nameof(Source.ChatFontFamily)
                        or nameof(Source.ChatFadeSeconds) or nameof(Source.Width) or nameof(Source.Height))
                        UpdatePreview(chatBox);
                };
                UpdatePreview(chatBox);
            }
    }
 }
@@ -0,0 +1,182 @@
 using System.Collections.Generic;
 using System.Globalization;
 using System.Windows;
 using System.Windows.Media;
 using System.Windows.Media.Imaging;
 using System.Windows.Threading;
 using ytLive.Models;
 namespace ytLive.Services.Compositor;
 /// <summary>
 /// Rasterizes the stream-alert ticker into a transparent BGRA strip that the
 /// output compositor overlays along the very top edge of the master frame
 /// (TASK 47). The strip is text ("Viewer — Super Chat · $12.34") inside a dark
 /// pill with the LlamaCasty accent bar, rendered ONCE per unique text on the UI
 /// thread (WPF <c>RenderTargetBitmap</c>, Pbgra32→straight-alpha like
 /// <see cref="SocialBarRenderer"/>), then cached. Each <see cref="Render"/> call
 /// is pure byte-math on that cached raster producing a scrolling marquee frame,
 /// so the frame pump can call it from any thread for every output frame at
 /// 30fps without a Dispatcher round-trip.
 /// </summary>
 public static class AlertTickerRenderer
 {
    /// <summary>Master-frame width — the ticker spans the full 1920px output.</summary>
    public const int Width = 1920;
    /// <summary>Strip height (pill + vertical padding).</summary>
    public const int Height = 48;
    private const int RepeatGap = 120;
    private const int CacheLimit = 48;
    /// <summary>How long each blink half lasts in <see cref="AlertDisplayMethod.Flash"/>
    /// (0.5s on, 0.5s off — a 1Hz pulse for the whole alert).</summary>
    public const double FlashHalfSeconds = 0.5;
    private static readonly object Gate = new();
    private static readonly Dictionary<string, VideoFrame> StripCache = new();
    /// <summary>A frame of <paramref name="text"/> presented per
    /// <paramref name="method"/> at <paramref name="elapsedSeconds"/> into the alert,
    /// or null when there is nothing to show (no text, or a Flash in its off half).
    /// Thread-safe: reads the cached raster and does row copies only.
    /// <para><see cref="AlertDisplayMethod.TickerScroll"/> paces itself from
    /// <paramref name="readsPerAlert"/> over <paramref name="alertSeconds"/> rather
    /// than a fixed pixels-per-second: the old constant (140px/s ≈ a 17s pass) meant
    /// a 10s alert showed the text barely once, entering from the right and never
    /// crossing. The creator's target is three readable passes per alert.</para>
    /// <para><paramref name="width"/>/<paramref name="height"/> default to the
    /// full-master strip. They are parameters because the ticker now renders INTO the
    /// Stream Alerts box (creator ruling 2026-09-26) and therefore has to be the box's
    /// size: a 1920-wide strip clipped to an 800px box would hide the announcement
    /// off the right edge for most of its pass, which is the opposite of readable.</para></summary>
    public static VideoFrame? Render(string? text, double elapsedSeconds,
        AlertDisplayMethod method = AlertDisplayMethod.TickerScroll,
        double alertSeconds = 0.0, int readsPerAlert = 3,
        int width = Width, int height = Height)
    {
        if (string.IsNullOrWhiteSpace(text)) return null;
        if (width <= 0 || height <= 0) return null;
        var strip = GetStrip(text!);
        if (strip == null) return null;
        if (method == AlertDisplayMethod.Flash
            && elapsedSeconds % (FlashHalfSeconds * 2) >= FlashHalfSeconds)
            return null; // off half of the pulse
        var x = method == AlertDisplayMethod.TickerScroll
            ? ScrollX(strip.Width, width, elapsedSeconds, alertSeconds, readsPerAlert)
            : (width - strip.Width) / 2; // Solid + Flash: centred, still
        var pixels = new byte[width * height * 4];
        CopyStrip(pixels, width, height, strip, x);
        if (method == AlertDisplayMethod.TickerScroll && x + strip.Width <= 0)
            CopyStrip(pixels, width, height, strip, x + width + RepeatGap); // wrapped tail enters
        return new VideoFrame(width, height, pixels);
    }
    /// <summary>Left edge of the pill for a marquee that must complete
    /// <paramref name="readsPerAlert"/> passes in <paramref name="alertSeconds"/>:
    /// one pass (off the right edge, across, out of sight) takes that long.
    /// <para>The run is phase-started half a frame in, so the very first frame of an
    /// alert already shows the announcement instead of a blank strip sitting exactly
    /// off the right edge.</para></summary>
    private static int ScrollX(int stripWidth, int width, double elapsedSeconds,
        double alertSeconds, int readsPerAlert)
    {
        var cycle = width + stripWidth + RepeatGap;
        var pass = Math.Max(0.5, alertSeconds) / Math.Max(1, readsPerAlert);
        var speed = cycle / pass;
        var pos = (width / 2 + (int)(elapsedSeconds * speed)) % cycle;
        return width - pos;
    }
    private static void CopyStrip(byte[] dst, int dstW, int dstH, VideoFrame strip, int dstX)
    {
        if (dstX >= dstW || dstX + strip.Width <= 0) return;
        var x0 = Math.Max(0, dstX);
        var x1 = Math.Min(dstW, dstX + strip.Width);
        var sx0 = x0 - dstX;
        var copyBytes = (x1 - x0) * 4;
        var sw = strip.Width;
        // The strip is rasterised at its natural 48px; the target box can be shorter,
        // and copying strip.Height rows into a shorter dst would run off the end of the
        // array. Clip the rows, not the buffer.
        var rows = Math.Min(strip.Height, dstH);
        for (var y = 0; y < rows; y++)
            Buffer.BlockCopy(strip.BgraPixels, (y * sw + sx0) * 4, dst, (y * dstW + x0) * 4, copyBytes);
    }
    private static VideoFrame? GetStrip(string text)
    {
        lock (Gate)
        {
            if (StripCache.TryGetValue(text, out var cached)) return cached;
        }
        var strip = RenderStrip(text);
        if (strip == null) return null;
        lock (Gate)
        {
            if (StripCache.Count >= CacheLimit) StripCache.Clear();
            if (!StripCache.TryGetValue(text, out var existing))
                StripCache[text] = strip;
            return StripCache[text];
        }
    }
    private static VideoFrame? RenderStrip(string text)
    {
        // WPF rendering is single-threaded; the pump thread resolves to the UI
        // thread at most once per unique text (then hits the cache).
        var app = Application.Current;
        if (app != null && !app.Dispatcher.CheckAccess())
        {
            VideoFrame? result = null;
            app.Dispatcher.Invoke(() => result = RenderStrip(text));
            return result;
        }
        const double pillHeight = 34;
        const double accentW = 6;
        const double padX = 16;
        const double gap = 8;
        var font = new Typeface(new FontFamily("Segoe UI"), FontStyles.Normal, FontWeights.SemiBold, FontStretches.Normal);
        var ft = new FormattedText(text, CultureInfo.InvariantCulture, FlowDirection.LeftToRight,
            font, 22, Brushes.White, 1.0);
        var pillW = (int)Math.Ceiling(padX + accentW + gap + ft.Width + padX);
        var top = (Height - pillHeight) / 2.0;
        var textTop = top + (pillHeight - ft.Height) / 2.0;
        var visual = new DrawingVisual();
        using (var dc = visual.RenderOpen())
        {
            var pill = new Rect(0, top, pillW, pillHeight);
            dc.DrawRoundedRectangle(new SolidColorBrush(Color.FromArgb(0xE6, 0x10, 0x13, 0x24)), null, pill, pillHeight / 2, pillHeight / 2);
            dc.DrawRoundedRectangle(new SolidColorBrush(Color.FromRgb(0xe9, 0x45, 0x60)), null,
                new Rect(padX, top + (pillHeight - 12) / 2.0, accentW, 12), 2, 2);
            dc.DrawText(ft, new Point(padX + accentW + gap, textTop));
        }
        var bitmap = new RenderTargetBitmap(pillW, Height, 96, 96, PixelFormats.Pbgra32);
        bitmap.Render(visual);
        var pixels = new byte[pillW * Height * 4];
        bitmap.CopyPixels(pixels, pillW * 4, 0);
        // Pbgra32 is premultiplied — unpremultiply so the compositor's
        // straight-alpha source-over doesn't halo the text edges.
        for (var i = 0; i < pixels.Length; i += 4)
        {
            var a = pixels[i + 3];
            if (a == 0 || a == 255) continue;
            pixels[i] = (byte)(pixels[i] * 255 / a);
            pixels[i + 1] = (byte)(pixels[i + 1] * 255 / a);
            pixels[i + 2] = (byte)(pixels[i + 2] * 255 / a);
        }
        return new VideoFrame(pillW, Height, pixels);
    }
 }
@@ -0,0 +1,421 @@
 using System;
 using System.Globalization;
 using System.Windows;
 using System.Windows.Media;
 using System.Windows.Media.Imaging;
 using System.Windows.Threading;
 namespace ytLive.Services.Compositor;
 /// <summary>
 /// The free-tier branding flash: a "made with LlamaCasty!" credit that is COMPOSITED
 /// INTO THE OUTPUT (recording or stream), not merely shown in the preview.
 /// <para>2026-09-26. This used to exist only as a WPF <c>BrandFlashLayer</c> in
 /// <c>PreviewPane.xaml</c> — a 0.25-opacity centred TextBlock the creator could see and
 /// no viewer ever could. The compositor has carried an unused <c>flashFrame</c> slot
 /// since then; this type is the producer that finally feeds it. It is wired on the
 /// PER-FRAME path only: <c>SceneGraph.GetBakedBase</c> also accepts a <c>flashFrame</c>,
 /// and that one is a trap — <c>SceneRegion.Matches</c> compares element ids only, so a
 /// flash folded into the baked static base would freeze there and never expire.</para>
 /// <para>The credit is deliberately obnoxious (creator directive 2026-09-26): full-opacity
 /// neon, a different random position every presentation, and a hard sell every 30–60s.
 /// It is gated on LICENCE state, never on a UI toggle — see <see cref="Enabled"/>.</para>
 /// </summary>
 public sealed class BrandFlashPresenter : IDisposable
 {
    /// <summary>The credit line, kept identical to the old preview TextBlock so the
    /// wording can never drift between the preview and the broadcast.</summary>
    public const string Text = "made with LlamaCasty!";
    // Presentation envelope (creator-specified 2026-09-26): 500ms fade in, the credit
    // held at full opacity for 1000ms, then a 500ms fade out — 2000ms end to end.
    public const double FadeInSeconds = 0.5;
    public const double HoldSeconds = 1.0;
    public const double FadeOutSeconds = 0.5;
    public const double PresentationSeconds = FadeInSeconds + HoldSeconds + FadeOutSeconds;
    /// <summary>Cadence: <c>rand(0, 30s) + 30s</c> ⇒ a flash every 30–60s, so it never
    /// lands on a beat a viewer could tune out.</summary>
    public const int IntervalFloorMs = 30_000;
    public const int IntervalJitterMs = 30_000;
    /// <summary>The first flash lands shortly after go-live (the stream-start
    /// impression); the random cadence takes over from there.</summary>
    public const double FirstFlashDelaySeconds = 5.0;
    /// <summary>Master-space canvas. Global overlays in this codebase are authored at
    /// master size and scaled by the compositor.</summary>
    public const int MasterWidth = 1920;
    public const int MasterHeight = 1080;
    /// <summary>Neon recipe taken from the established overlay look (see commit
    /// message): a bright near-white CORE plus a feathered multi-radius HALO, with the
    /// red and blue channels pushed in OPPOSITE directions — Maxon's "Chromatic Glow"
    /// notes the green channel is all but invisible behind white text once R and B are
    /// split, which is exactly the look.</summary>
    private static readonly Color NeonRed = Color.FromRgb(0xe9, 0x45, 0x60);  // brand red, exact
    private static readonly Color NeonBlue = Color.FromRgb(0x4d, 0x8b, 0xff); // brand blue #0f3460 lifted for luminance
    private static readonly Color CoreColor = Colors.White;
    /// <summary>Font size chosen so the credit spans roughly half the master width:
    /// big enough to read as advertising, small enough that the random placement has
    /// real travel room (a full-width line could only ever sit at x≈0).</summary>
    private const double FontSize = 120;
    private const double GlowPadding = 34;
    private const double TickSeconds = 0.033;
    private readonly Random _random;
    private readonly DispatcherTimer? _timer;
    private readonly object _gate = new();
    private bool _enabled = true;
    private bool _running;
    private double _sinceStart;
    private double _nextFlashAt;      // absolute time of the next flash, _sinceStart's reference
    private double _elapsed;            // seconds into the presentation; >= PresentationSeconds means idle
    private VideoFrame? _raster;        // tight, full-opacity glowing credit (straight alpha)
    private byte[]? _buffer;            // reused master-space BGRA — hence the Epoch bump below
    private int _atX, _atY;
    private long _epoch;
    public BrandFlashPresenter(Random? random = null)
    {
        _random = random ?? new Random();
        if (Application.Current is { } app)
        {
            _timer = new DispatcherTimer { Interval = TimeSpan.FromSeconds(TickSeconds) };
            _timer.Tick += (_, _) => Advance(TickSeconds);
        }
    }
    /// <summary>The licence gate, driven by <c>MainViewModel.IsPremium</c> (Polar
    /// validation) and NOT by a user-facing toggle: once this credit is composited into
    /// the broadcast it is the thing standing between a paying customer's stream and an
    /// advertisement, so it is re-checked on every read. A premium user mid-presentation
    /// loses the flash on the very next tick rather than at the end of the credit.</summary>
    public bool Enabled
    {
        get { lock (_gate) return _enabled; }
        set
        {
            bool restart;
            lock (_gate)
            {
                if (_enabled == value) return;
                _enabled = value;
                if (!value)
                {
                    // Licence state only ever goes premium → no flash. Cut the current
                    // presentation short instead of running it out ungated.
                    _elapsed = PresentationSeconds;
                    _timer?.Stop();
                    restart = false;
                }
                else
                {
                    // …but a DOWNGRADE (key entered mid-session) must bring the cadence
                    // back. The presenter now runs for the life of the app — Start() is
                    // called once at startup, not per go-live — so stopping the timer on
                    // the premium edge without restarting it here would leave the credit
                    // dead until the process is restarted, even after a valid key.
                    restart = _running;
                }
            }
            if (restart) _timer?.Start();
        }
    }
    /// <summary>True while a credit is on screen (drives the preview's visibility).</summary>
    public bool IsPresenting
    {
        get { lock (_gate) return _enabled && _elapsed < PresentationSeconds; }
    }
    /// <summary>Test-only: is the <see cref="DispatcherTimer"/> that drives
    /// <see cref="Advance"/> actually running? The premium/downgrade edge is the only
    /// thing that ever stops and restarts it now that the presenter is started once for
    /// the life of the app, and a synchronous test body cannot observe a real timer
    /// tick — so assert the decision directly instead of sleeping through a 30–60s
    /// interval. Never call this from product code.</summary>
    internal bool IsCadenceTimerEnabled => _timer?.IsEnabled ?? false;
    /// <summary>Begin the cadence: first flash <see cref="FirstFlashDelaySeconds"/>
    /// after the call, then every <c>rand(30s) + 30s</c>.</summary>
    public void Start()
    {
        EnsureRaster();
        lock (_gate)
        {
            _running = true;
            _sinceStart = 0;
            _nextFlashAt = FirstFlashDelaySeconds;
        }
        if (_enabled) _timer?.Start();
    }
    public void Stop()
    {
        lock (_gate)
        {
            _running = false;
            _elapsed = PresentationSeconds;
        }
        _timer?.Stop();
    }
    /// <summary>Advance the presentation clock. Also the deterministic test seam: tests
    /// drive this directly and never call <see cref="Start"/>, so no timer is running
    /// and the clock only moves when the test moves it (mirrors <c>AlertOverlayLayer.Advance</c>).</summary>
    public void Advance(double deltaSeconds)
    {
        // Rasterise BEFORE taking the lock. WPF text formatting is UI-thread affine, so
        // this can hop to the dispatcher — and a blocking hop while holding _gate would
        // deadlock against a timer tick that wants the same lock.
        EnsureRaster();
        lock (_gate)
        {
            if (!_enabled) return;
            if (_running)
            {
                _sinceStart += deltaSeconds;
                if (_sinceStart >= _nextFlashAt)
                {
                    // The interval runs FROM THIS FLASH, not from Start(). An absolute
                    // deadline here made the gaps shrink every cycle (5s, then whatever
                    // was left of the previous interval) and collapse toward zero.
                    _nextFlashAt = _sinceStart + NextIntervalSeconds();
                    BeginPresentation();
                }
            }
            if (_elapsed < PresentationSeconds)
            {
                _elapsed += deltaSeconds;
                if (_elapsed >= PresentationSeconds) _elapsed = PresentationSeconds;
            }
        }
        Notify();
    }
    /// <summary>Invoked on the UI thread at the end of every tick with the frame that
    /// tick produced (null when nothing is due) — the preview's repaint hook, so the
    /// preview and the broadcast are driven by ONE clock.</summary>
    public Action<VideoFrame?>? OnFrame { get; set; }
    private void Notify()
    {
        var cb = OnFrame;
        if (cb == null) return;
        // Read OUTSIDE the state lock: the callback is arbitrary code and must never
        // run while _gate is held.
        var frame = Frame;
        if (frame == null) { cb(null); return; }
        if (Application.Current is { } app && !app.Dispatcher.CheckAccess())
        {
            // Off the UI thread (a test driving the clock). The frame's buffer is
            // recycled, so hand the deferred copy its own pixels.
            var copy = new byte[frame.BgraPixels.Length];
            Buffer.BlockCopy(frame.BgraPixels, 0, copy, 0, copy.Length);
            app.Dispatcher.BeginInvoke(() => cb(new VideoFrame(frame.Width, frame.Height, copy)));
        }
        else
        {
            cb(frame);
        }
    }
    /// <summary>Force a presentation now — the "show me the flash" path and the test seam.</summary>
    public void Show()
    {
        EnsureRaster();
        lock (_gate)
        {
            if (!_enabled) return;
            BeginPresentation();
        }
    }
    private double NextIntervalSeconds()
        => (IntervalFloorMs + _random.Next(IntervalJitterMs)) / 1000.0;
    private void BeginPresentation()
    {
        if (_raster == null) return;
        _buffer ??= new byte[MasterWidth * MasterHeight * 4];
        // A new presentation can land anywhere, so the previous credit's pixels must go
        // before this one is written or the old spot ghosts through the fade. One 8MB
        // clear per presentation (not per tick) keeps that cheap.
        Array.Clear(_buffer);
        var spot = ComputePlacement(_raster.Width, _raster.Height, MasterWidth, MasterHeight, _random);
        _atX = (int)spot.X;
        _atY = (int)spot.Y;
        _elapsed = 0;
    }
    /// <summary>
    /// The credit for the output compositor and the preview: a master-space frame holding
    /// the glowing text at this presentation's random spot, alpha-scaled to the current
    /// point on the fade envelope. Null when idle, or unlicensed.
    /// <para><b>The frame's pixel buffer is recycled across ticks</b> (only the text rect
    /// is rewritten) and its <see cref="VideoFrame.Epoch"/> is bumped every read, so the
    /// compositor's buffer-identity paste cache can never false-hit a stale credit.
    /// Consumers blit synchronously — copy the pixels if you need to keep them.</para></summary>
    public VideoFrame? Frame
    {
        get
        {
            lock (_gate)
            {
                if (!_enabled || _elapsed >= PresentationSeconds || _raster == null || _buffer == null)
                    return null;
                var opacity = OpacityAt(_elapsed);
                if (opacity <= 0) return null;
                Paint(_buffer, _raster, _atX, _atY, opacity);
                return new VideoFrame(MasterWidth, MasterHeight, _buffer) { Epoch = ++_epoch };
            }
        }
    }
    /// <summary>Full → hold → empty. Public and static so the preview and the tests
    /// agree with the renderer instead of re-deriving the curve.</summary>
    public static double OpacityAt(double elapsedSeconds)
    {
        if (elapsedSeconds < 0 || elapsedSeconds >= PresentationSeconds) return 0;
        if (elapsedSeconds < FadeInSeconds) return elapsedSeconds / FadeInSeconds;
        if (elapsedSeconds < FadeInSeconds + HoldSeconds) return 1.0;
        return 1.0 - ((elapsedSeconds - (FadeInSeconds + HoldSeconds)) / FadeOutSeconds);
    }
    /// <summary>
    /// A random top-left offset that keeps the whole credit ON the canvas. The text is a
    /// single pre-measured line, so it can never wrap — this is the "how far can the
    /// left margin travel" limit the creator described: <c>0 … (canvas - creditWidth)</c>
    /// horizontally, likewise vertically. Pure + static, so the rule is directly testable.
    /// </summary>
    public static Point ComputePlacement(int creditWidth, int creditHeight,
        int canvasWidth, int canvasHeight, Random random)
    {
        var maxX = Math.Max(0, canvasWidth - creditWidth);
        var maxY = Math.Max(0, canvasHeight - creditHeight);
        return new Point(random.Next(0, maxX + 1), random.Next(0, maxY + 1));
    }
    /// <summary>Rewrite the credit rect into the master buffer with alpha scaled to
    /// <paramref name="opacity"/>. The rect is fully overwritten each tick and the spot
    /// is fixed for the whole presentation, so nothing stale accumulates and no clear
    /// pass is needed here.</summary>
    private static void Paint(byte[] buffer, VideoFrame raster, int atX, int atY, double opacity)
    {
        for (var y = 0; y < raster.Height; y++)
        {
            var dst = ((atY + y) * MasterWidth + atX) * 4;
            var src = y * raster.Stride;
            for (var x = 0; x < raster.Width; x++)
            {
                var a = raster.BgraPixels[src + x * 4 + 3];
                if (a == 0) continue;
                buffer[dst + x * 4] = raster.BgraPixels[src + x * 4];
                buffer[dst + x * 4 + 1] = raster.BgraPixels[src + x * 4 + 1];
                buffer[dst + x * 4 + 2] = raster.BgraPixels[src + x * 4 + 2];
                buffer[dst + x * 4 + 3] = (byte)Math.Round(a * opacity);
            }
        }
    }
    /// <summary>Build the credit raster once, on the UI thread, and publish it under
    /// the lock. Called from every clock entry point, so it is a no-op after the first.</summary>
    private void EnsureRaster()
    {
        lock (_gate) { if (_raster != null) return; }
        var raster = RenderNeonText(Text);
        lock (_gate) { if (raster != null) { _raster = raster; } }
    }
    // ── rasterisation ──────────────────────────────────────────────────────────
    /// <summary>
    /// Rasterize the credit once, tight to the glyphs plus glow, on the UI thread (WPF
    /// <c>RenderTargetBitmap</c>, Pbgra32→straight alpha exactly like
    /// <see cref="AlertTickerRenderer"/>) and cached — this is per-text work, not
    /// per-frame, so the pump can afford to run every tick at 30fps.
    /// <para>The neon is a bright core plus a feathered halo: the glyphs redrawn at
    /// shrinking radii with rising alpha, the two colours offset in opposite directions,
    /// which is what makes it read as a lit tube rather than a drop shadow.</para></summary>
    private static VideoFrame? RenderNeonText(string text)
    {
        if (Application.Current is { } app && !app.Dispatcher.CheckAccess())
        {
            VideoFrame? result = null;
            app.Dispatcher.Invoke(() => result = RenderNeonText(text));
            return result;
        }
        var font = new Typeface(new FontFamily("Segoe UI"), FontStyles.Normal,
            FontWeights.Bold, FontStretches.Normal);
        var probe = new FormattedText(text, CultureInfo.InvariantCulture,
            FlowDirection.LeftToRight, font, FontSize, Brushes.White, 1.0);
        var w = (int)Math.Ceiling(probe.Width) + (int)(GlowPadding * 2);
        var h = (int)Math.Ceiling(probe.Height) + (int)(GlowPadding * 2);
        if (w <= 0 || h <= 0) return null;
        var visual = new DrawingVisual();
        using (var dc = visual.RenderOpen())
        {
            // Three halo rings per colour. Wide+dim first, then progressively tighter and
            // brighter, so the falloff is feathered instead of a hard-edged blob.
            foreach (var (radius, alpha) in new[] { (30.0, 0.16), (20.0, 0.26), (11.0, 0.40) })
            {
                DrawHalo(dc, text, font, radius, alpha, NeonRed, +1);
                DrawHalo(dc, text, font, radius, alpha, NeonBlue, -1);
            }
            // A tight white bloom hugging the glyphs sells the brightness of the tube.
            DrawHalo(dc, text, font, 4.0, 0.55, CoreColor, +1);
            // The core itself, sharp and opaque, drawn last.
            dc.DrawText(new FormattedText(text, CultureInfo.InvariantCulture,
                FlowDirection.LeftToRight, font, FontSize, new SolidColorBrush(CoreColor), 1.0),
                new Point(GlowPadding, GlowPadding));
        }
        var bitmap = new RenderTargetBitmap(w, h, 96, 96, PixelFormats.Pbgra32);
        bitmap.Render(visual);
        var pixels = new byte[w * h * 4];
        bitmap.CopyPixels(pixels, w * 4, 0);
        // Pbgra32 is premultiplied — unpremultiply, or straight-alpha source-over in the
        // compositor haloes the glyph edges.
        for (var i = 0; i < pixels.Length; i += 4)
        {
            var a = pixels[i + 3];
            if (a == 0 || a == 255) continue;
            pixels[i] = (byte)(pixels[i] * 255 / a);
            pixels[i + 1] = (byte)(pixels[i + 1] * 255 / a);
            pixels[i + 2] = (byte)(pixels[i + 2] * 255 / a);
        }
        return new VideoFrame(w, h, pixels);
    }
    private static void DrawHalo(DrawingContext dc, string text, Typeface font,
        double radius, double alpha, Color color, int direction)
    {
        var brush = new SolidColorBrush(color);
        const int spokes = 12;
        for (var i = 0; i < spokes; i++)
        {
            var angle = 2 * Math.PI * i / spokes;
            brush.Opacity = alpha;
            var ft = new FormattedText(text, CultureInfo.InvariantCulture,
                FlowDirection.LeftToRight, font, FontSize, brush, 1.0);
            dc.DrawText(ft, new Point(
                GlowPadding + Math.Cos(angle) * radius * direction,
                GlowPadding + Math.Sin(angle) * radius * direction));
        }
    }
    public void Dispose() => _timer?.Stop();
 }
@@ -1,3 +1,6 @@
 using System.Buffers;
 using System.Collections.Generic;
 using ytLive.Helpers;
 using ytLive.Models;
 namespace ytLive.Services.Compositor;
@@ -14,12 +17,32 @@ namespace ytLive.Services.Compositor;
 /// </summary>
 public sealed class SceneCompositor
 {
    // Paste cache (take-8 fix, 2026-09-04): the Live scene re-sampled ~680k bilinear
    // pixels EVERY tick even though only the camera actually changes at that rate —
    // chat/web/image layers are identical frame after frame. Same shape as OBS (the
    // source surface is cached, the compositor blits): a scaled/round-clipped/mirrored
    // layer rasterizes once and is pasted (row-copy/blend) on every later tick.
    // Keyed by the SOURCE FRAME IDENTITY (array + Epoch + CropBounds) — producers hand
    // out fresh immutable byte[], or recycled-ring arrays whose monotonic Epoch distinguishes
    // each generation (screen capture, take-11 fix). CropBounds must be in the key because
    // the same frame (same Pixels/Epoch/Width/Height) can have different CropBounds as
    // the element is resized — a stale cached raster with wrong crop pixels would corrupt
    // the output. Bounds-checked eviction clears wholesale.
    private sealed record PasteKey(byte[] Pixels, long Epoch, int SrcW, int SrcH, int DstW, int DstH, bool Round, bool Mirror, (int X, int Y, int W, int H)? CropBounds);
    private static readonly Dictionary<PasteKey, VideoFrame> _pasteCache = new();
    private static readonly Dictionary<SceneElement, VideoFrame> _elementRasters = new(ReferenceEqualityComparer.Instance);
    private static readonly object _pasteGate = new();
    private const int MaxPasteEntries = 256;
    /// <summary>
    /// Composite <paramref name="scene"/> into the tier's output frame. Layer order (back →
    /// front): live background (the scene's <c>IsBackground</c> source) → background image →
    /// visible elements (z-order = <c>Elements</c> order, mirroring the XAML DataTemplate) →
    /// branding flash → social bar (a global overlay; spans the master width at
-    /// <paramref name="socialBarTop"/>). Transparent regions read opaque black.
+    /// <paramref name="socialBarTop"/>) → stream-alert ticker (drawn INSIDE the Stream
    /// Alerts box, at the origin the frame carries on <see cref="VideoFrame.Placement"/>;
    /// creator ruling 2026-09-26 — it used to be a global bar pinned to the very top).
    /// Transparent regions read opaque black.
    /// </summary>
    public VideoFrame Render(
        Scene scene,
@@ -27,7 +50,11 @@ public sealed class SceneCompositor
        VideoFrame? flashFrame,
        CompositorOptions options,
        VideoFrame? socialBarFrame = null,
-        int socialBarTop = 0)
+        int socialBarTop = 0,
        VideoFrame? staticBase = null,
        int split = -1,
        byte[]? scratch = null,
        VideoFrame? tickerFrame = null)
    {
        if (scene == null) throw new ArgumentNullException(nameof(scene));
        if (frameFor == null) throw new ArgumentNullException(nameof(frameFor));
@@ -39,46 +66,122 @@ public sealed class SceneCompositor
        var cropW = options.SourceRectWidth;
        var cropH = options.SourceRectHeight;
-        var buffer = new byte[cropW * cropH * 4];
+        var buffer = scratch != null && scratch.Length == cropW * cropH * 4
-        for (var i = 3; i < buffer.Length; i += 4)
+            ? scratch
-            buffer[i] = 255; // opaque black base — video frames are never transparent
+            : new byte[cropW * cropH * 4];
-        var elements = scene.Elements;
+        // staticBase != null: the caller pre-baked all static layers below `split`.
-
+        // We copy it (never mutate the cached base) and composite elements[split..] on top.
-        var liveCapture = elements.OfType<Source>().FirstOrDefault(s => s.IsBackground);
+        if (staticBase != null)
        var liveCaptureFrame = liveCapture != null && liveCapture.IsVisible ? frameFor(liveCapture) : null;
        if (liveCaptureFrame != null)
            BlitContent(buffer, cropW, cropH, 0, 0, cropW, cropH, liveCaptureFrame, 1f, false, false);
        var background = elements.OfType<Source>().FirstOrDefault(s => s.Type == SourceType.Background);
        var backgroundFrame = background != null ? frameFor(background) : null;
        if (backgroundFrame != null)
            BlitContent(buffer, cropW, cropH, 0, 0, cropW, cropH, backgroundFrame, 1f, false, false);
        foreach (var element in elements)
        {
            if (staticBase.Width != cropW || staticBase.Height != cropH)
                throw new ArgumentException("The static base must match the source rect.", nameof(staticBase));
            Buffer.BlockCopy(staticBase.BgraPixels, 0, buffer, 0, buffer.Length);
        }
        else
        {
            if (split < 0) split = scene.Elements.Count;
            var elements = scene.Elements;
            var liveCapture = elements.OfType<Source>().FirstOrDefault(s => s.IsBackground);
            var liveCaptureFrame = liveCapture != null && liveCapture.IsVisible ? frameFor(liveCapture) : null;
            // A master-sized live backdrop paints every pixel of the base — the
            // opaque-black pre-fill (2M byte writes) would be dead work. Capture
            // frames are opaque BGRA by contract (the WinRT path ignores alpha),
            // so the 1:1 row walk covers the full rect.
            var covered = liveCaptureFrame != null
                && liveCaptureFrame.Width == cropW && liveCaptureFrame.Height == cropH;
            if (!covered)
            {
                if (liveCaptureFrame != null)
                {
                    var (uScale, uOx, uOy) = StretchMath.UniformToFill(cropW, cropH, liveCaptureFrame.Width, liveCaptureFrame.Height);
                    var drawnW = liveCaptureFrame.Width * uScale;
                    var drawnH = liveCaptureFrame.Height * uScale;
                    var ox = (int)Math.Floor(uOx);
                    var oy = (int)Math.Floor(uOy);
                    var oh = (int)Math.Ceiling(oy + drawnH);
                    var ow = cropW;
                    if (oy > 0)
                    {
                        var topCount = oy * ow;
                        for (var i = 3; i < topCount * 4; i += 4)
                            buffer[i] = 255;
                    }
                    if (oh < cropH)
                    {
                        var start = oh * ow;
                        var bottomCount = (cropH - oh) * ow;
                        for (var i = start * 4 + 3; i < (start + bottomCount) * 4; i += 4)
                            buffer[i] = 255;
                    }
                    if (ox > 0 || (int)Math.Ceiling(uOx + drawnW) < cropW)
                    {
                        var x0s = (int)Math.Floor(uOx);
                        var x1s = (int)Math.Ceiling(uOx + drawnW);
                        for (var y = oy; y < oh && y < cropH; y++)
                        {
                            var di = (y * ow + 0) * 4;
                            for (var x = 0; x < x0s && x < ow; x++)
                            {
                                buffer[di + x * 4 + 3] = 255;
                            }
                            for (var x = x1s; x < ow; x++)
                            {
                                buffer[di + x * 4 + 3] = 255;
                            }
                        }
                    }
                }
                else
                {
                    for (var i = 3; i < buffer.Length; i += 4)
                        buffer[i] = 255; // opaque black base
                }
            }
            if (liveCaptureFrame != null)
                BlitContent(buffer, cropW, cropH, 0, 0, cropW, cropH, liveCaptureFrame, 1f, false, false);
            var background = elements.OfType<Source>().FirstOrDefault(s => s.Type == SourceType.Background);
            var backgroundFrame = background != null ? frameFor(background) : null;
            if (backgroundFrame != null)
                BlitContent(buffer, cropW, cropH, 0, 0, cropW, cropH, backgroundFrame, 1f, false, false);
            foreach (var element in elements)
            {
                if (!element.IsVisible) continue;
                switch (element)
                {
                    case Source { IsBackground: true }:
                    case Source { Type: SourceType.Background }:
                    case Source { Type: SourceType.TextOverlay }:
                    case ZoomSceneElement { IsZoomActive: true }:
                        continue;
                }
                var fullFrame = frameFor(element);
                if (fullFrame == null) continue;
                BlitBakedElement(buffer, cropW, cropH, options, element, fullFrame);
            }
        }
        // Composite the above-split layers (dynamic + any static above them) per frame.
        for (var i = Math.Max(0, split); i < scene.Elements.Count; i++)
        {
            var element = scene.Elements[i];
            if (!element.IsVisible) continue;
            switch (element)
            {
                case Source { IsBackground: true }:
                case Source { Type: SourceType.Background }:
                case Source { Type: SourceType.TextOverlay }:
-                    continue; // background/background are their own layers; Text isn't shipped
+                case ZoomSceneElement { IsZoomActive: true }:
                    continue;
            }
            var frame = frameFor(element);
            if (frame == null) continue;
-
+            BlitBakedElement(buffer, cropW, cropH, options, element, frame);
            var ex = (float)(element.X - options.SourceRectX);
            var ey = (float)(element.Y - options.SourceRectY);
            var ew = (float)element.Width;
            var eh = (float)element.Height;
            var isRound = element.ClipShape == ClipShape.Round;
            BlitContent(buffer, cropW, cropH, ex, ey, ew, eh, frame,
                (float)element.Opacity, isRound, element.IsMirrored);
            if (element.HasBorder)
                DrawBorder(buffer, cropW, cropH, ex, ey, ew, eh, element, isRound);
        }
        if (flashFrame != null)
@@ -87,10 +190,255 @@ public sealed class SceneCompositor
        if (socialBarFrame != null && socialBarFrame.Width > 0 && socialBarFrame.Height > 0)
            BlitOverlay(buffer, cropW, cropH, options, socialBarFrame, 0, socialBarTop);
        if (tickerFrame != null && tickerFrame.Width > 0 && tickerFrame.Height > 0)
            BlitOverlay(buffer, cropW, cropH, options, tickerFrame, tickerFrame.OriginX, tickerFrame.OriginY);
        // The zoom box is layer n+1: a live 2x view of a FIXED capture window sampled
        // from the frame just composited (all layers). Drawn LAST — above everything.
        // The box/2 capture is anchored at the click, so dragging the box only moves
        // the box; the content it shows never changes (creator ruling 2026-10-08).
        var zoom = scene.Elements.OfType<ZoomSceneElement>().FirstOrDefault(z => z.IsZoomActive);
        if (zoom != null)
            BlitZoom(buffer, cropW, cropH, options, zoom);
        return StretchMath.BilinearScale(
            new VideoFrame(cropW, cropH, buffer), options.OutputWidth, options.OutputHeight);
    }
    /// <summary>
    /// Render the static base of a scene: the opaque black layer, the live-capture
    /// background, the background image, and every <paramref name="split"/> z-layers
    /// below the split point (all of which are static by construction — see
    /// <see cref="SceneElement.Kind"/>). The result is a source-rect sized frame that
    /// <see cref="Render"/> can start from and composite the dynamic/above-split layers
    /// onto each tick. Returns null when there is no static layer at all.
    /// </summary>
    public static VideoFrame? BakeStaticBase(
        Scene scene,
        int split,
        Func<SceneElement, VideoFrame?> frameFor,
        Func<CompositorOptions> options,
        VideoFrame? socialBarFrame = null,
        int socialBarTop = 0,
        VideoFrame? flashFrame = null)
    {
        if (split <= 0) return null;
        var opts = options();
        if (opts.SourceRectWidth <= 0 || opts.SourceRectHeight <= 0) return null;
        var cropW = opts.SourceRectWidth;
        var cropH = opts.SourceRectHeight;
        var buffer = new byte[cropW * cropH * 4];
        for (var i = 3; i < buffer.Length; i += 4)
            buffer[i] = 255;
        var elements = scene.Elements;
        var liveCapture = elements.OfType<Source>().FirstOrDefault(s => s.IsBackground);
        if (liveCapture != null)
        {
            var liveCaptureFrame = liveCapture.IsVisible ? frameFor(liveCapture) : null;
            if (liveCaptureFrame != null && split > elements.IndexOf(liveCapture))
                BlitContent(buffer, cropW, cropH, 0, 0, cropW, cropH, liveCaptureFrame, 1f, false, false);
        }
        var background = elements.OfType<Source>().FirstOrDefault(s => s.Type == SourceType.Background);
        if (background != null)
        {
            var backgroundFrame = frameFor(background);
            if (backgroundFrame != null && split > elements.IndexOf(background))
                BlitContent(buffer, cropW, cropH, 0, 0, cropW, cropH, backgroundFrame, 1f, false, false);
        }
        for (var i = 0; i < split; i++)
        {
            var element = scene.Elements[i];
            if (!element.IsVisible) continue;
            switch (element)
            {
                case Source { IsBackground: true }:
                case Source { Type: SourceType.Background }:
                case Source { Type: SourceType.TextOverlay }:
                case ZoomSceneElement:
                    continue;
            }
            var frame = frameFor(element);
            if (frame == null) continue;
            BlitBakedElement(buffer, cropW, cropH, opts, element, frame);
        }
        var baked = new VideoFrame(cropW, cropH, buffer);
        if (flashFrame != null)
            baked = Overlay(baked, opts, flashFrame, 0, 0);
        if (socialBarFrame != null && socialBarFrame.Width > 0 && socialBarFrame.Height > 0)
            baked = Overlay(baked, opts, socialBarFrame, 0, socialBarTop);
        return baked;
    }
    /// <summary>The compositor's dynamic/above-split path: start from an existing frame
    /// buffer and composite the z-layers from <paramref name="split"/> onward on top.
    /// When <paramref name="baseFrame"/> is null the caller must fall back to full render.
    /// The social bar never reaches here (it IS baked into the static base) but the alert
    /// ticker must: it is dynamic by construction — only ever present while an alert plays —
    /// so it overlays LAST, pinned to the very top (TASK 47).</summary>
    public static VideoFrame CompositeLayers(
        VideoFrame baseFrame,
        Scene scene,
        int split,
        Func<SceneElement, VideoFrame?> frameFor,
        CompositorOptions options,
        VideoFrame? socialBarFrame = null,
        int socialBarTop = 0,
        VideoFrame? flashFrame = null,
        byte[]? scratch = null,
        VideoFrame? tickerFrame = null)
    {
        var cropW = options.SourceRectWidth;
        var cropH = options.SourceRectHeight;
        // We must not mutate the cached base: copy it into a fresh (or pooled) buffer.
        var buffer = scratch != null && scratch.Length == baseFrame.BgraPixels.Length
            ? scratch
            : new byte[baseFrame.BgraPixels.Length];
        Buffer.BlockCopy(baseFrame.BgraPixels, 0, buffer, 0, baseFrame.BgraPixels.Length);
        for (var i = split; i < scene.Elements.Count; i++)
        {
            var element = scene.Elements[i];
            if (!element.IsVisible) continue;
            switch (element)
            {
                case Source { IsBackground: true }:
                case Source { Type: SourceType.Background }:
                case Source { Type: SourceType.TextOverlay }:
                case ZoomSceneElement { IsZoomActive: true }:
                    continue;
            }
            var frame = frameFor(element);
            if (frame == null) continue;
            BlitBakedElement(buffer, cropW, cropH, options, element, frame);
        }
        if (tickerFrame != null && tickerFrame.Width > 0 && tickerFrame.Height > 0)
            BlitOverlay(buffer, cropW, cropH, options, tickerFrame, tickerFrame.OriginX, tickerFrame.OriginY);
        var zoom = scene.Elements.OfType<ZoomSceneElement>().FirstOrDefault(z => z.IsZoomActive);
        if (zoom != null)
            BlitZoom(buffer, cropW, cropH, options, zoom);
        return StretchMath.BilinearScale(new VideoFrame(cropW, cropH, buffer), options.OutputWidth, options.OutputHeight);
    }
    private static void BlitBakedElement(
        byte[] buffer, int cropW, int cropH, CompositorOptions options, SceneElement element, VideoFrame frame)
    {
        var ex = (float)(element.X - options.SourceRectX);
        var ey = (float)(element.Y - options.SourceRectY);
        var ew = (float)element.Width;
        var eh = (float)element.Height;
        var isRound = element.ClipShape == ClipShape.Round;
        // All rect-placed elements route through the paste cache (take-9 lesson): the
        // IsOpaque bypass kept re-sampling the webcam (~156k px) EVERY tick even when
        // the device frame had not changed; an opaque source rasterizes to an opaque
        // raster whose paste is a per-pixel copy branch, so hits beat the sampler and
        // misses cost exactly what the bypass cost.
        BlitCachedLayer(buffer, cropW, cropH, ex, ey, ew, eh, frame, element, isRound);
        if (element.HasBorder)
            DrawBorder(buffer, cropW, cropH, ex, ey, ew, eh, element, isRound);
    }
    /// <summary>Non-opaque layer blit through the paste cache: the element-space raster
    /// (scaled to the element rect, round-clipped, mirrored) depends only on the source
    /// frame + rect + shape/mirror — NOT on position or opacity. Static content (chat,
    /// web overlays, images, the media frame between updates) is sampled ONCE and pasted
    /// at integer position with per-tixel blend; only layers whose source frame actually
    /// changed (webcam at device fps) pay resampling.</summary>
    private static void BlitCachedLayer(
        byte[] buffer, int cropW, int cropH,
        float ex, float ey, float ew, float eh,
        VideoFrame frame, SceneElement element, bool isRound)
    {
        if (ew <= 0 || eh <= 0) return;
        var dw = (int)System.Math.Ceiling(ew);
        var dh = (int)System.Math.Ceiling(eh);
        if (dw <= 0 || dh <= 0) return;
        var mirror = element.IsMirrored;
        PasteKey? key = null;
        VideoFrame? raster = null;
        lock (_pasteGate)
        {
            key = new PasteKey(frame.BgraPixels, frame.Epoch, frame.Width, frame.Height, dw, dh, isRound, mirror, frame.CropBounds);
            _pasteCache.TryGetValue(key, out raster);
        }
        if (raster == null)
        {
            // Rasterize in ELEMENT space on a TRANSPARENT base: the sampler writes 255
            // alpha only where it actually draws, so untouched margins (outside the
            // round clip, past the UniformToFill edges) stay alpha 0 and the paste
            // reveals the master beneath instead of black. The ARRAY is reused per
            // element (see _elementRasters note) — new source generations re-raster
            // in place, so the steady state allocates nothing.
            lock (_pasteGate)
            {
                if (_elementRasters.TryGetValue(element, out var existing)
                    && existing.Width == dw && existing.Height == dh)
                    raster = existing;
            }
            if (raster == null) raster = new VideoFrame(dw, dh, new byte[dw * dh * 4]);
            Array.Clear(raster.BgraPixels);
            BlitContentRaw(raster.BgraPixels, dw, dh, 0, 0, ew, eh, frame, 1f, isRound, mirror, transparentDst: true);
            lock (_pasteGate)
            {
                // Only the SOURCE frame's identity is a real key owner; drop any older
                // entry that shared this element's reused raster so a stale key can never
                // paste a mid-update array.
                if (_pasteCache.Count >= MaxPasteEntries) _pasteCache.Clear();
                _pasteCache[key!] = raster;
                _elementRasters[element] = raster;
            }
        }
        // Paste at integer position; opacity blends. The raster is never flagged
        // IsOpaque — round clips/margins carry alpha 0 — so the row blend always runs.
        var op = (int)(System.Math.Clamp(element.Opacity, 0f, 1f) * 256);
        if (op <= 0) return;
        var px = (int)System.Math.Floor(ex);
        var py = (int)System.Math.Floor(ey);
        var x0 = System.Math.Max(0, px);
        var y0 = System.Math.Max(0, py);
        var x1 = System.Math.Min(cropW, px + dw);
        var y1 = System.Math.Min(cropH, py + dh);
        if (x0 >= x1 || y0 >= y1) return;
        var s = raster.BgraPixels;
        StripPool.For(y0, y1, y =>
        {
            var si = ((y - py) * dw + (x0 - px)) * 4;
            var len = x1 - x0;
            if (op == 256)
                BlendRowOpaque(buffer, (y * cropW + x0) * 4, s, si, len);
            else
                BlendRowWeighted(buffer, (y * cropW + x0) * 4, s, si, len, op);
        });
    }
    /// <summary>Copy <paramref name="frame"/> and blit a global overlay onto the copy
    /// at (sx0, sy0) in crop space. internal (not private) because the frame pump's
    /// fully-static path needs it: that path stretches the cached bake straight to the
    /// output, so any per-frame overlay — social bar, alert ticker, brand flash — has to
    /// be composited here first. Copying is the whole point: the bake is cached, and a
    /// flash written straight into it would freeze there and never expire.</summary>
    internal static VideoFrame Overlay(VideoFrame frame, CompositorOptions options, VideoFrame overlay, int sx0, int sy0)
    {
        var cropW = options.SourceRectWidth;
        var cropH = options.SourceRectHeight;
        var buffer = new byte[frame.BgraPixels.Length];
        Buffer.BlockCopy(frame.BgraPixels, 0, buffer, 0, buffer.Length);
        BlitOverlay(buffer, cropW, cropH, options, overlay, sx0, sy0);
        return new VideoFrame(cropW, cropH, buffer);
    }
    /// <summary>
    /// Render a cross-fade blend between two scenes. Used by <see cref="TransitionService"/>
    /// during fade/move transitions: the caller renders each scene individually, then blends
@@ -131,26 +479,144 @@ public sealed class SceneCompositor
    {
        if (ew <= 0 || eh <= 0) return;
        var (scale, ox, oy) = StretchMath.UniformToFill(ew, eh, src.Width, src.Height);
        // 1:1 aligned fast path (the full-frame backdrop, master-sized overlays):
        // bilinear sampling at scale 1 with integer offsets is the identity, so the
        // blit is a row walk, not 2M float samples + rounds. Research-first (2026-09-03,
        // take-3 fix; libyuv's row-based BLEND_NONE pattern —
        // https://chromium.googlesource.com/libyuv/libyuv/): the 258ms/frame render
        // that time-lapsed take 3 lived in the general loop below.
        if (!isRound && !isMirror && scale == 1f && ox == 0f && oy == 0f
            && ex == MathF.Floor(ex) && ey == MathF.Floor(ey))
        {
            Blit1To1Rows(dst, dstW, dstH, (int)ex, (int)ey, src, opacity);
            return;
        }
        BlitContentRaw(dst, dstW, dstH, ex, ey, ew, eh, src, opacity, isRound, isMirror);
    }
    /// <summary>The general scaled/clipped/mirrored sampler (integer fixed-point
    /// bilinear + source-over). Also rasterizes paste-cache entries in ELEMENT space
    /// onto a TRANSPARENT base (alpha 0) so pasting over the master keeps the round
    /// clip and transparency of the untouched margins.</summary>
    private static void BlitContentRaw(
        byte[] dst, int dstW, int dstH,
        float ex, float ey, float ew, float eh,
        VideoFrame src, float opacity, bool isRound, bool isMirror,
        bool transparentDst = false)
    {
        if (ew <= 0 || eh <= 0) return;
        float scale, ox, oy, invScale;
        float drawnW, drawnH;
        // No CropBounds means "the whole source canvas is the crop region" — cbW/cbH
        // MUST default to the full source dims, not 0. A zero cbW/cbH makes every
        // sxCrop/syCrop below evaluate to 0 regardless of position, collapsing the
        // entire sampled rect to source pixel (0,0) (the webcam gray-block regression,
        // 2026-09-12: introduced by the CropBounds Fill-style scaling work the same
        // day — CropBounds-bearing sources, i.e. the web widget, were never affected).
        var cbX = 0;
        var cbY = 0;
        var cbW = src.Width;
        var cbH = src.Height;
        if (src.CropBounds is { } cb)
        {
            cbX = cb.X;
            cbY = cb.Y;
            cbW = cb.W;
            cbH = cb.H;
            scale = Math.Max(ew / cbW, eh / cbH);
            invScale = 1f / scale;
            drawnW = cbW * scale;
            drawnH = cbH * scale;
            ox = (ew - drawnW) / 2f;
            oy = (eh - drawnH) / 2f;
        }
        else
        {
            var (uScale, uOx, uOy) = StretchMath.UniformToFill(ew, eh, src.Width, src.Height);
            scale = uScale;
            invScale = 1f / uScale;
            ox = uOx;
            oy = uOy;
            drawnW = src.Width * uScale;
            drawnH = src.Height * uScale;
        }
        var radius = Math.Min(ew, eh) / 2f;
        var cx = ew / 2f;
        var cy = eh / 2f;
        var x0 = Math.Max(0, (int)Math.Floor(ex));
        var y0 = Math.Max(0, (int)Math.Floor(ey));
        var x1 = Math.Min(dstW - 1, (int)Math.Ceiling(ex + ew));
        var y1 = Math.Min(dstH - 1, (int)Math.Ceiling(ey + eh));
        if (x0 > x1 || y0 > y1) return;
-        var (scale, ox, oy) = StretchMath.UniformToFill(ew, eh, src.Width, src.Height);
+        var op = (int)(Math.Clamp(opacity, 0f, 1f) * 256);
-        var drawnW = src.Width * scale;
+        if (op <= 0) return;
-        var drawnH = src.Height * scale;
+        var s = src.BgraPixels;
-        var radius = Math.Min(ew, eh) / 2f;
+        var srcStride = src.Width; // canvas stride in pixels (not bytes)
        var cx = ew / 2f;
        var cy = eh / 2f;
-        for (var y = y0; y <= y1; y++)
+        // Build horizontal LUT for scaled blit to reduce per-pixel divides. The table is
        // READ by the strip workers while it is being sampled, so it must not be shared
        // mutable state: it comes from the thread-safe ArrayPool and goes back in a finally
        // (the static single-buffer version raced the moment the strips went parallel).
        var lutCount = x1 - x0 + 1;
        var sxLut = ArrayPool<float>.Shared.Rent(lutCount);
        try
        {
-            for (var x = x0; x <= x1; x++)
+            var pxBase = x0 - ex;
            for (var xi = 0; xi < lutCount; xi++)
            {
-                var px = x - ex; // element space
+                var px = pxBase + xi;
-                var py = y - ey;
+                float sxCanvas;
-                if (px < ox || px > ox + drawnW || py < oy || py > oy + drawnH) continue;
+                if (px < ox || px > ox + drawnW)
                {
                    sxCanvas = float.NaN;
                }
                else
                {
                    var sxNorm = (px - ox) / drawnW;
                    sxNorm = sxNorm < 0f ? 0f : sxNorm > 1f ? 1f : sxNorm;
                    var sxCrop = sxNorm * cbW;
                    sxCanvas = cbX + sxCrop;
                    if (sxCanvas < 0f) sxCanvas = 0f;
                    if (sxCanvas > src.Width - 1f) sxCanvas = src.Width - 1f;
                    if (isMirror) sxCanvas = src.Width - 1f - sxCanvas;
                }
                sxLut[xi] = sxCanvas;
            }
            StripPool.For(y0, y1 + 1, y =>
        {
            var py = y - ey;
            if (py < oy || py > oy + drawnH) return;
            // syNorm: normalized [0,1] position within the drawn content (vertically)
            var syNorm = (py - oy) / drawnH;
            if (syNorm < 0f) syNorm = 0f;
            if (syNorm > 1f) syNorm = 1f;
            // syCrop: pixel position within the crop region
            var syCrop = syNorm * cbH;
            // syCanvas: canvas pixel row (for buffer indexing)
            var syCanvas = cbY + syCrop;
            if (syCanvas < 0f) syCanvas = 0f;
            if (syCanvas > src.Height - 1f) syCanvas = src.Height - 1f;
            var syi = (int)syCanvas;
            var sy1i = Math.Min(syi + 1, src.Height - 1);
            var fy8 = (int)((syCanvas - syi) * 256);
            var fyInv = 256 - fy8;
            var di = (y * dstW + x0) * 4;
            for (var xi = 0; xi < lutCount; xi++, di += 4)
            {
                var sxCanvas = sxLut[xi];
                if (float.IsNaN(sxCanvas)) continue;
                var px = pxBase + xi;
                if (isRound)
                {
                    var dx = px - cx;
@@ -158,12 +624,176 @@ public sealed class SceneCompositor
                    if (dx * dx + dy * dy > radius * radius) continue;
                }
-                var sx = (px - ox) / scale;
+                var sxi = (int)sxCanvas;
-                var sy = (py - oy) / scale;
+                var sx1i = Math.Min(sxi + 1, src.Width - 1);
-                if (isMirror) sx = src.Width - 1 - sx;
+                var fx8 = (int)((sxCanvas - sxi) * 256);
-                var sample = StretchMath.SampleBgra(src.BgraPixels, src.Width, src.Height, sx, sy);
+                var fxInv = 256 - fx8;
-                BlendPixel(dst, (y * dstW + x) * 4, sample, opacity);
+
                // ALL pixel indexing uses srcStride (canvas stride), NOT crop width
                var p00 = (syi * srcStride + sxi) * 4;
                var p10 = (syi * srcStride + sx1i) * 4;
                var p01 = (sy1i * srcStride + sxi) * 4;
                var p11 = (sy1i * srcStride + sx1i) * 4;
                var sb = Bilinear(s[p00], s[p10], s[p01], s[p11], fx8, fxInv, fy8, fyInv);
                var sg = Bilinear(s[p00 + 1], s[p10 + 1], s[p01 + 1], s[p11 + 1], fx8, fxInv, fy8, fyInv);
                var sr = Bilinear(s[p00 + 2], s[p10 + 2], s[p01 + 2], s[p11 + 2], fx8, fxInv, fy8, fyInv);
                var saFull = Bilinear(s[p00 + 3], s[p10 + 3], s[p01 + 3], s[p11 + 3], fx8, fxInv, fy8, fyInv);
                var sa = saFull * op >> 8;
                if (sa >= 255)
                {
                    dst[di] = (byte)sb;
                    dst[di + 1] = (byte)sg;
                    dst[di + 2] = (byte)sr;
                    dst[di + 3] = 255;
                }
                else if (sa > 0)
                {
                    if (transparentDst)
                    {
                        // Element-raster pass on a TRANSPARENT base (the paste cache):
                        // keep straight color + straight alpha so the paste rows can
                        // source-over onto the opaque master. Premultiplying here (the
                        // opaque-dst blend) stamped alpha 255 onto already-alpha-scaled
                        // color — the paste over-wrote the scene with darkened ink, the
                        // web widget's "black box" in recordings.
                        dst[di] = (byte)sb;
                        dst[di + 1] = (byte)sg;
                        dst[di + 2] = (byte)sr;
                        dst[di + 3] = (byte)sa;
                    }
                    else
                    {
                        var inv = 255 - sa;
                        dst[di] = (byte)((sb * sa + dst[di] * inv + 127) / 255);
                        dst[di + 1] = (byte)((sg * sa + dst[di + 1] * inv + 127) / 255);
                        dst[di + 2] = (byte)((sr * sa + dst[di + 2] * inv + 127) / 255);
                        dst[di + 3] = 255;
                    }
                }
            }
            });
        }
        finally
        {
            ArrayPool<float>.Shared.Return(sxLut);
        }
    }
    /// <summary>Two-stage bilinear in 8.8 fixed point; result within ±1 of the
    /// float StretchMath.SampleBgra (well inside every pixel test's ±2 tolerance).
    /// The first stage must NOT shift back to 8 bits — shifting twice collapsed
    /// every solid-255 sample to 1 (green overwrites silently degraded to no-ops;
    /// caught by the SceneCompositor/SceneGraph pixel probes 2026-09-04).</summary>
    private static int Bilinear(int tl, int tr, int bl, int br, int fx8, int fxInv, int fy8, int fyInv)
    {
        // Both stages in one 16.8 scale: top/bot ≤ 65280, ×256 + round ≤ 16.8M — int-safe.
        var top = tl * fxInv + tr * fx8;
        var bot = bl * fxInv + br * fx8;
        return (top * fyInv + bot * fy8 + 32768) >> 16;
    }
    /// <summary>Row walk for a 1:1 aligned blit at integer offset (ex, ey): per-pixel
    /// branch on source alpha — opaque rows copy straight, transparent pixels are
    /// skipped, partial alpha blends in integer fixed-point (libyuv's pattern). The
    /// master buffer's destination alpha is always opaque (black base paints 255 and
    /// every blend writes 255), so dst alpha is never read — matching BlendPixel's
    /// source-over result for opaque dst within ±1.</summary>
    private static void Blit1To1Rows(byte[] dst, int dstW, int dstH, int ex, int ey, VideoFrame src, float opacity)
    {
        var op = (int)(Math.Clamp(opacity, 0f, 1f) * 256);
        if (op <= 0) return;
        var x0 = Math.Max(0, ex);
        var y0 = Math.Max(0, ey);
        var x1 = Math.Min(dstW, ex + src.Width);
        var y1 = Math.Min(dstH, ey + src.Height);
        if (x0 >= x1 || y0 >= y1) return;
        // The take-4 fix: a full-canvas opaque capture (the Live backdrop) is ONE
        // memcpy, not 2.07M managed loop iterations — the row walk below still cost
        // ~58ms/frame dominated by bounds-check arithmetic and GC of the per-pixel
        // loop's slowness, i.e. the same starvation shape as take 3, one floor lower.
        if (op == 256 && src.IsOpaque && x0 == 0 && y0 == 0 && x1 == dstW && y1 == dstH)
        {
            Buffer.BlockCopy(src.BgraPixels, 0, dst, 0, dstW * dstH * 4);
            return;
        }
        // Opaque source with 1:1 aligned region covering full canvas
        if (op == 256 && src.IsOpaque && ex == 0 && ey == 0 && src.Width == dstW && src.Height == dstH)
        {
            Buffer.BlockCopy(src.BgraPixels, 0, dst, 0, dstW * dstH * 4);
            return;
        }
        var d = dst.AsSpan();
        var s = src.BgraPixels.AsSpan();
        var rowLen = x1 - x0;
        if (op == 256)
        {
            for (var y = y0; y < y1; y++)
            {
                var si = ((y - ey) * src.Width + (x0 - ex)) * 4;
                BlendRowOpaque(d, (y * dstW + x0) * 4, s, si, rowLen);
            }
        }
        else
        {
            for (var y = y0; y < y1; y++)
            {
                var si = ((y - ey) * src.Width + (x0 - ex)) * 4;
                BlendRowWeighted(d, (y * dstW + x0) * 4, s, si, rowLen, op);
            }
        }
    }
    private static void BlendRowOpaque(Span<byte> dst, int di, ReadOnlySpan<byte> src, int si, int count)
    {
        for (var n = 0; n < count; n++)
        {
            var a = src[si + 3];
            if (a == 255)
            {
                dst[di] = src[si];
                dst[di + 1] = src[si + 1];
                dst[di + 2] = src[si + 2];
                dst[di + 3] = 255;
            }
            else if (a != 0)
            {
                var inv = 255 - a;
                dst[di] = (byte)((src[si] * a + dst[di] * inv + 127) / 255);
                dst[di + 1] = (byte)((src[si + 1] * a + dst[di + 1] * inv + 127) / 255);
                dst[di + 2] = (byte)((src[si + 2] * a + dst[di + 2] * inv + 127) / 255);
                dst[di + 3] = 255;
            }
            si += 4;
            di += 4;
        }
    }
    private static void BlendRowWeighted(Span<byte> dst, int di, ReadOnlySpan<byte> src, int si, int count, int op)
    {
        for (var n = 0; n < count; n++)
        {
            var a = src[si + 3] * op >> 8;
            if (a >= 255)
            {
                dst[di] = src[si];
                dst[di + 1] = src[si + 1];
                dst[di + 2] = src[si + 2];
                dst[di + 3] = 255;
            }
            else if (a > 0)
            {
                var inv = 255 - a;
                dst[di] = (byte)((src[si] * a + dst[di] * inv + 127) / 255);
                dst[di + 1] = (byte)((src[si + 1] * a + dst[di + 1] * inv + 127) / 255);
                dst[di + 2] = (byte)((src[si + 2] * a + dst[di + 2] * inv + 127) / 255);
                dst[di + 3] = 255;
            }
            si += 4;
            di += 4;
        }
    }
@@ -201,22 +831,40 @@ public sealed class SceneCompositor
    }
    /// <summary>1:1 copy of a master-sized overlay (flash, social bar) cropped to the
-    /// active source rect. The overlay is positioned in master space by (sx0, sy0).</summary>
+    /// active source rect. The overlay is positioned in master space by (sx0, sy0).
    /// Iterates only the intersection rect — the old loop walked every destination
    /// pixel to blit a ~64px strip (2M iterations of bounds checks per overlay).</summary>
    private static void BlitOverlay(
        byte[] dst, int dstW, int dstH, CompositorOptions options,
        VideoFrame overlay, int sx0, int sy0)
    {
-        for (var y = 0; y < dstH; y++)
+        var dx0 = Math.Max(0, sx0 - options.SourceRectX);
        var dy0 = Math.Max(0, sy0 - options.SourceRectY);
        var dx1 = Math.Min(dstW, sx0 - options.SourceRectX + overlay.Width);
        var dy1 = Math.Min(dstH, sy0 - options.SourceRectY + overlay.Height);
        StripPool.For(dy0, dy1, y =>
        {
-            for (var x = 0; x < dstW; x++)
+            var si = ((y + options.SourceRectY - sy0) * overlay.Width
-            {
+                + dx0 + options.SourceRectX - sx0) * 4;
-                var sx = x + options.SourceRectX - sx0;
+            BlendRowOpaque(dst, (y * dstW + dx0) * 4, overlay.BgraPixels, si, dx1 - dx0);
-                var sy = y + options.SourceRectY - sy0;
+        });
-                if (sx < 0 || sy < 0 || sx >= overlay.Width || sy >= overlay.Height) continue;
+    }
-                var sample = StretchMath.SampleBgra(overlay.BgraPixels, overlay.Width, overlay.Height, sx, sy);
+
-                BlendPixel(dst, (y * dstW + x) * 4, sample, 1f);
+    /// <summary>
-            }
+    /// The zoom box layer (n+1): map the element's master-space box and capture to
-        }
+    /// crop space and 2x-magnify the capture onto the box from the composed frame.
    /// The active zoom element is never blitted by the normal layer loops — the
    /// switch skips it and this pass draws it above everything, last.
    /// </summary>
    private static void BlitZoom(
        byte[] dst, int cropW, int cropH, CompositorOptions options, ZoomSceneElement zoom)
    {
        ZoomMagnifier.MagnifyInto(
            dst, cropW, cropH,
            zoom.X - options.SourceRectX, zoom.Y - options.SourceRectY,
            zoom.Width, zoom.Height,
            zoom.CaptureX - options.SourceRectX, zoom.CaptureY - options.SourceRectY,
            zoom.ClipShape == ClipShape.Round);
    }
    /// <summary>Straight-alpha source-over blend; the frame's alpha (and the layer opacity) drives coverage.</summary>
@@ -16,14 +16,19 @@ public static class StaticPixelCache
    public static VideoFrame? Get(string assetId)
    {
        if (string.IsNullOrWhiteSpace(assetId)) return null;
-        if (Cache.TryGetValue(assetId, out var frame)) return frame;
+        // Locked: the frame pump decodes from its own thread now (take-8 off-UI fix),
        // so the dictionary genuinely races with UI-path callers (snapshots, heals).
        lock (Cache)
        {
            if (Cache.TryGetValue(assetId, out var frame)) return frame;
-        var bytes = LayoutStore.Instance?.GetAssetBytes(assetId);
+            var bytes = LayoutStore.Instance?.GetAssetBytes(assetId);
-        if (bytes == null || bytes.Length == 0) return null;
+            if (bytes == null || bytes.Length == 0) return null;
-        var decoded = Decode(bytes);
+            var decoded = Decode(bytes);
-        if (decoded != null) Cache[assetId] = decoded;
+            if (decoded != null) Cache[assetId] = decoded;
-        return decoded;
+            return decoded;
        }
    }
    public static VideoFrame? Decode(byte[] bytes)
@@ -0,0 +1,116 @@
 using System;
 using System.Buffers;
 namespace ytLive.Services.Compositor;
 /// <summary>
 /// The zoom box's magnifier (creator-corrected model, 2026-10-08): the box is a
 /// detached 2x view of a FIXED capture window — the box/2 region centred on the
 /// spot the creator clicked — sampled from the ALREADY-COMPOSITED frame (every
 /// layer: live backdrop, art, webcam, sources, alerts). Moving the box relocates
 /// it on screen without changing the capture; the box is painted LAST (layer n+1)
 /// so it sits above everything. The capture snapshot is taken before the box is
 /// drawn, so a box overlapping its own source never recurses.
 /// </summary>
 internal static class ZoomMagnifier
 {
    /// <summary>
    /// Magnify a box/2 capture window onto a box/2&#x2009;² box in <paramref name="dst"/>
    /// (an opaque, already-composited crop-space buffer). dst pixel centres map to
    /// capture coords as <c>cap + (dstLocal + 0.5) / 2</c> — the exact 2x the preview's
    /// VisualBrush shows via a box/2 Viewbox with Stretch=Fill. <paramref name="round"/>
    /// clips the box to a true circle (zoom shape Circle).
    /// </summary>
    internal static void MagnifyInto(
        byte[] dst, int dstW, int dstH,
        double boxX, double boxY, double boxW, double boxH,
        double capX, double capY,
        bool round)
    {
        if (boxW <= 0 || boxH <= 0) return;
        if (dstW <= 0 || dstH <= 0) return;
        // Integer box draw bounds (clamped to the buffer).
        var bx0 = Math.Max(0, (int)Math.Floor(boxX));
        var by0 = Math.Max(0, (int)Math.Floor(boxY));
        var bx1 = Math.Min(dstW, (int)Math.Ceiling(boxX + boxW));
        var by1 = Math.Min(dstH, (int)Math.Ceiling(boxY + boxH));
        if (bx0 >= bx1 || by0 >= by1) return;
        var bw = bx1 - bx0;
        var bh = by1 - by0;
        // Integer capture-window read bounds (the 2x window is box/2, clamped).
        var rx0 = Math.Max(0, (int)Math.Floor(capX));
        var ry0 = Math.Max(0, (int)Math.Floor(capY));
        var rx1 = Math.Min(dstW, (int)Math.Ceiling(capX + boxW / 2.0));
        var ry1 = Math.Min(dstH, (int)Math.Ceiling(capY + boxH / 2.0));
        var rw = rx1 - rx0;
        var rh = ry1 - ry0;
        if (rw <= 0 || rh <= 0) return;
        // Snapshot the capture first: the box may overlap its own source region.
        var src = ArrayPool<byte>.Shared.Rent(rw * rh * 4);
        try
        {
            for (var y = 0; y < rh; y++)
                Buffer.BlockCopy(dst, ((ry0 + y) * dstW + rx0) * 4, src, y * rw * 4, rw * 4);
            var radius = Math.Min(boxW, boxH) / 2.0;
            var ccx = boxX + boxW / 2.0;
            var ccy = boxY + boxH / 2.0;
            for (var y = 0; y < bh; y++)
            {
                var dy = by0 + y;
                var sy = capY + (dy + 0.5 - boxY) * 0.5 - ry0;
                if (sy < 0.0) sy = 0.0;
                if (sy > rh - 1.0) sy = rh - 1.0;
                var syi = (int)sy;
                var syInv = Math.Min(syi + 1, rh - 1);
                var fy8 = (int)((sy - syi) * 256);
                var fyInv = 256 - fy8;
                var di = (dy * dstW + bx0) * 4;
                for (var x = 0; x < bw; x++, di += 4)
                {
                    var dx = bx0 + x;
                    if (round)
                    {
                        var ox = dx - ccx;
                        var oy = dy - ccy;
                        if (ox * ox + oy * oy > radius * radius) continue;
                    }
                    var sx = capX + (dx + 0.5 - boxX) * 0.5 - rx0;
                    if (sx < 0.0) sx = 0.0;
                    if (sx > rw - 1.0) sx = rw - 1.0;
                    var sxi = (int)sx;
                    var sxInv = Math.Min(sxi + 1, rw - 1);
                    var fx8 = (int)((sx - sxi) * 256);
                    var fxInv = 256 - fx8;
                    var p00 = (syi * rw + sxi) * 4;
                    var p10 = (syi * rw + sxInv) * 4;
                    var p01 = (syInv * rw + sxi) * 4;
                    var p11 = (syInv * rw + sxInv) * 4;
                    dst[di] = (byte)Bilinear(src[p00], src[p10], src[p01], src[p11], fx8, fxInv, fy8, fyInv);
                    dst[di + 1] = (byte)Bilinear(src[p00 + 1], src[p10 + 1], src[p01 + 1], src[p11 + 1], fx8, fxInv, fy8, fyInv);
                    dst[di + 2] = (byte)Bilinear(src[p00 + 2], src[p10 + 2], src[p01 + 2], src[p11 + 2], fx8, fxInv, fy8, fyInv);
                    dst[di + 3] = 255;
                }
            }
        }
        finally
        {
            ArrayPool<byte>.Shared.Return(src);
        }
    }
    /// <summary>Two-stage bilinear in 8.8 fixed point (same precision as
    /// <see cref="SceneCompositor"/>'s sampler).</summary>
    private static int Bilinear(int tl, int tr, int bl, int br, int fx8, int fxInv, int fy8, int fyInv)
    {
        var top = tl * fxInv + tr * fx8;
        var bot = bl * fxInv + br * fx8;
        return (top * fyInv + bot * fy8 + 32768) >> 16;
    }
 }
@@ -2,7 +2,9 @@ namespace ytLive.Services.Encoder;
 /// <summary>
 /// Builds the FFmpeg command line for a live RTMP push (TASK 4 ship step 3):
-/// raw BGRA frames via stdin (paced <c>-re</c>), real audio via the named pipe
+/// raw BGRA frames via stdin (paced by the frame pump — the pump holds a strict
 /// CFR cadence, so <c>-re</c> would only add a second, fighting pacer), real
 /// audio via the named pipe
 /// (TASK 9 — the mixer streams f32le at 48 kHz stereo into <c>\\.\pipe\&lt;name&gt;</c>;
 /// WASAPI loopback + the mic ride the pipe instead of the old anullsrc silence),
 /// H.264 + AAC encoding, FLV muxing to the ingestion URL. Pure — the encoder
@@ -16,7 +18,6 @@ public static class FfmpegArgs
        {
            "-hide_banner", "-loglevel", "info",
            "-stats", "-stats_period", "0.5",
            "-re",
            "-f", "rawvideo", "-pix_fmt", "bgra",
            "-video_size", $"{options.Width}x{options.Height}",
            "-framerate", options.Fps.ToString(),
@@ -1,4 +1,6 @@
 using System.Buffers;
 using System.Diagnostics;
 using System.Threading.Channels;
 using ytLive.Helpers;
 using ytLive.Models;
@@ -30,6 +32,21 @@ public sealed class FfmpegEncoder : IFfmpegEncoder
    private Task? _stderrLoop;
    private bool _stopRequested;
    // Pipe decoupling (slice 10, 2026-09-10): a bounded pending-frame queue drained
    // by its own task (the OBS video-thread → encoder-queue model — the encoder's
    // thread never couples back into the video thread; libobs obs-encoder.c). The
    // pump's SubmitFrameAsync now ENQUEUES (copying into a pooled buffer) instead of
    // blocking on WriteAsync when ffmpeg lags the pipe; overflow DROPS the newest
    // frame (skip-newest) and counts it. BoundedChannelFullMode.Wait + TryWrite gives
    // exactly that: when full, TryWrite returns false and the caller drops the item.
    private const int QueueCapacity = 120; // ~2s at the tier's 60fps
    private readonly Channel<PendingWrite> _frames = Channel.CreateBounded<PendingWrite>(
        new BoundedChannelOptions(QueueCapacity) { SingleReader = true });
    private Task? _drainTask;
    private int _droppedBackpressure;
    private readonly record struct PendingWrite(byte[] Buffer, int Length);
    public FfmpegEncoder(
        IFfmpegLocator locator,
        Func<IEncoderProcess>? processFactory = null)
@@ -40,6 +57,13 @@ public sealed class FfmpegEncoder : IFfmpegEncoder
    public bool IsRunning { get; private set; }
    /// <summary>Frames dropped by the bounded queue because the drain task couldn't
    /// keep the pipe fed (the encoder lagging the real-time capture rate). The pump
    /// reports this in its stats; the burned-in frame counter in the recording
    /// shows the identical jumps. Distinct from <see cref="StreamHealth.DroppedFrames"/>
    /// (ffmpeg's own progress-derived estimate).</summary>
    public int DroppedFrames => Volatile.Read(ref _droppedBackpressure);
    public async Task StartAsync(EncoderOptions options, CancellationToken cancellationToken = default)
    {
        if (options == null) throw new ArgumentNullException(nameof(options));
@@ -93,26 +117,40 @@ public sealed class FfmpegEncoder : IFfmpegEncoder
        _stopRequested = false;
        _stderrLoop = RunStderrLoopAsync(process);
        StartDrainLoop(process);
    }
    /// <summary>
-    /// Write one raw BGRA frame to ffmpeg's stdin. Serialized internally; callers
+    /// Enqueue one raw BGRA frame for ffmpeg's stdin (slice 10). The caller races
-    /// (the compositor pump) may race freely. Frames are written as-is — the caller
+    /// freely (the compositor pump); this never blocks on the pipe. The pixels are
-    /// paces to capture rate (the compositor's job, ship step 5).
+    /// copied into a pooled buffer first because — unlike the old direct write — the
    /// write happens later on the drain thread, so the caller may (and does) recycle
    /// its scratch buffer the moment this returns. When the bounded queue is full the
    /// NEWEST frame is dropped and counted (freshness over coverage; the encoder is
    /// already behind, so the stale-content failure mode never encodes).
    /// </summary>
-    public async Task SubmitFrameAsync(VideoFrame frame, CancellationToken cancellationToken = default)
+    public Task SubmitFrameAsync(VideoFrame frame, CancellationToken cancellationToken = default)
    {
        if (frame == null) throw new ArgumentNullException(nameof(frame));
        IEncoderProcess? process;
        lock (_gate)
        {
            if (!IsRunning) throw new InvalidOperationException("The encoder is not running.");
            process = _process;
        }
-        var bytes = frame.BgraPixels;
+        if (cancellationToken.IsCancellationRequested)
-        await process!.StandardInput.WriteAsync(bytes, cancellationToken).ConfigureAwait(false);
+            return Task.FromCanceled(cancellationToken);
-        await process.StandardInput.FlushAsync(cancellationToken).ConfigureAwait(false);
+
        var pooled = ArrayPool<byte>.Shared.Rent(frame.BgraPixels.Length);
        Buffer.BlockCopy(frame.BgraPixels, 0, pooled, 0, frame.BgraPixels.Length);
        if (_frames.Writer.TryWrite(new PendingWrite(pooled, frame.BgraPixels.Length)))
            return Task.CompletedTask;
        // Queue full (encoder lagging) or the channel completed during stop — drop the
        // newest and count it. The caller never blocks; the encoder catches up or the
        // session ends with a (reported) short gap instead of a frozen stall.
        ArrayPool<byte>.Shared.Return(pooled);
        Interlocked.Increment(ref _droppedBackpressure);
        return Task.CompletedTask;
    }
    public async Task StopAsync(CancellationToken cancellationToken = default)
@@ -127,13 +165,17 @@ public sealed class FfmpegEncoder : IFfmpegEncoder
            loop = _stderrLoop;
        }
        // Flush every queued frame, then EOF: TryComplete lets the drain task write
        // the buffered frames, close stdin → ffmpeg finalizes and exits by itself
        // (the "did not exit after EOF" kill below is only the backstop).
        try
        {
-            process!.StandardInput.Dispose(); // EOF → ffmpeg finalizes + exits
+            _frames.Writer.TryComplete();
            if (_drainTask != null) await _drainTask.ConfigureAwait(false);
        }
        catch (Exception ex)
        {
-            AppLog.Write(ex, "FFmpeg encoder: closing stdin failed");
+            AppLog.Write(ex, "FFmpeg encoder: drain loop faulted during stop");
        }
        try
@@ -178,6 +220,7 @@ public sealed class FfmpegEncoder : IFfmpegEncoder
    public void Dispose()
    {
        _frames.Writer.TryComplete(); // unblock a stuck drain loop alongside the kill
        lock (_gate)
        {
            if (!IsRunning) return;
@@ -188,6 +231,54 @@ public sealed class FfmpegEncoder : IFfmpegEncoder
        }
    }
    /// <summary>
    /// The drain task (slice 10): owns every stdin write, so pipe backpressure — the
    /// pump's old stall — lives HERE, on a thread the pump never touches. Frames are
    /// written exactly as queued (the pooled array through its recorded length —
    /// ArrayPool may return a larger buffer), returned to the pool after the write
    /// copies into the pipe, and stdin is closed (EOF) once the queue drains.
    /// </summary>
    private void StartDrainLoop(IEncoderProcess process)
    {
        _drainTask = Task.Run(async () =>
        {
            try
            {
                try
                {
                    while (await _frames.Reader.WaitToReadAsync().ConfigureAwait(false))
                    {
                        while (_frames.Reader.TryRead(out var pending))
                        {
                            await process.StandardInput.WriteAsync(pending.Buffer, 0, pending.Length)
                                .ConfigureAwait(false);
                            await process.StandardInput.FlushAsync().ConfigureAwait(false);
                            ArrayPool<byte>.Shared.Return(pending.Buffer);
                        }
                    }
                }
                catch (ChannelClosedException)
                {
                    // channel completed while waiting — fall through to EOF
                }
                catch (Exception ex)
                {
                    AppLog.Write(ex, "FFmpeg encoder: drain loop write faulted");
                }
                finally
                {
                    // EOF on every path — a byte that sits in the pool when the pipe
                    // breaks is garbage anyway, and ffmpeg MUST see the close to finalize.
                    process.StandardInput.Dispose();
                }
            }
            catch (Exception ex)
            {
                AppLog.Write(ex, "FFmpeg encoder: drain loop faulted");
            }
        });
    }
    private async Task<string> ProbeEncoderAsync(string ffmpegPath, CancellationToken cancellationToken)
    {
        try
@@ -230,14 +321,35 @@ public sealed class FfmpegEncoder : IFfmpegEncoder
                    OnStderrLine(process, line);
                }
-                var code = process.ExitCode;
+                // Read the exit code defensively: the stop path disposes the process
-                var stillRunning = false;
+                // while this loop may still be waking (2026-09-01 "No process is
-                lock (_gate) stillRunning = IsRunning;
+                // associated with this object" — a cosmetic race that poisoned the log).
-                if (stillRunning && !_stopRequested && code != 0)
+                int exitCode;
                try
                {
-                    AppLog.Write($"FFmpeg encoder: subprocess exited unexpectedly ({code})");
+                    exitCode = process.ExitCode;
-                    _health.LastError = $"FFmpeg exited with code {code}";
+                }
-                    ProcessFailed?.Invoke(this, $"FFmpeg exited with code {code}");
+                catch (Exception)
                {
                    exitCode = -1;
                }
                var stillRunning = false;
                var stopping = false;
                lock (_gate)
                {
                    stillRunning = IsRunning;
                    stopping = _stopRequested;
                }
                if (stillRunning && !stopping)
                {
                    // ANY exit we did not ask for is a failure — including code 0.
                    // The old `code != 0` gate let ffmpeg's clean early exit vanish
                    // without a word while the pump kept feeding a corpse
                    // (2026-09-01 first real recording: died at ~0.9s, zero logs).
                    AppLog.Write($"FFmpeg encoder: subprocess exited unexpectedly (code {exitCode})");
                    _health.LastError = $"FFmpeg exited with code {exitCode}";
                    ProcessFailed?.Invoke(this, $"FFmpeg exited with code {exitCode}");
                }
            }
            catch (Exception ex)
@@ -250,7 +362,17 @@ public sealed class FfmpegEncoder : IFfmpegEncoder
    private void OnStderrLine(IEncoderProcess process, string line)
    {
        var progress = FfmpegProgressParser.TryParse(line);
-        if (progress == null) return;
+        if (progress == null)
        {
            // THE EYES: everything ffmpeg says that isn't a progress line — startup
            // config, warnings, the real reason it quit. Was silently discarded
            // (2026-09-01: encoder died at ~0.9s, log silent). Truncated so a
            // \r-choked stats blob can't flood; noise now beats blindness.
            var text = line.Trim('\r', ' ', '\t');
            if (text.Length > 0)
                AppLog.Write($"ffmpeg: {(text.Length > 400 ? text[..400] + "…" : text)}");
            return;
        }
        var dropped = Math.Max(0, (long)Math.Round(progress.Value.Fps * progress.Value.Duration.TotalSeconds) - progress.Value.Frame);
@@ -1,125 +1,81 @@
 using System.IO;
 using System.IO.Compression;
 using System.Net.Http;
 using ytLive.Helpers;
 namespace ytLive.Services.Encoder;
 /// <summary>
-/// The default <see cref="IFfmpegLocator"/>: probe PATH first (the user's own
+/// The default <see cref="IFfmpegLocator"/>: resolve the <b>bundled</b> FFmpeg that ships
-/// install wins), then the cache in <c>%APPDATA%\ytLlive\tools</c>, then pull the
+/// next to the app, falling back to PATH for anyone who deliberately installed their own.
-/// pinned BtbN **lgpl-shared** build (TASK 4 ship step 2). The shared variant is a
+///
-/// deliberate licensing choice: dynamic linking means LGPL compliance is "license
+/// <para><b>Nothing is downloaded.</b> This type used to pin a BtbN release URL, download
-/// text + source offer", with no static-relink (LGPL §6) material required. The
+/// the zip on first run, and execute it — which is Windows Store policy 10.2.2 (dynamic
-/// shared zip puts <c>ffmpeg.exe</c> plus the <c>libav*.dll</c> family in <c>bin/</c>,
+/// code inclusion, cited in <c>TASKS/research-store-certification.md</c> §4) and already
-/// so both are extracted — Windows resolves the DLLs from the exe's own directory.
+/// cost a real failure: the pin aged out of BtbN's 14-day retention and the download
-/// Search dirs, tools dir, and the downloader are constructor-injected so tests
+/// <b>404'd on the creator's first real recording attempt</b> (2026-09-01). The binaries
-/// fake the network and stay on a temp directory.
+/// are now fetched at BUILD time by <c>scripts/fetch-ffmpeg.sh</c> (pinned URL + SHA-256)
 /// and copied into <c>ffmpeg/</c> beside the executable.</para>
 ///
 /// <para><b>Order is bundled-first, deliberately.</b> The old code probed PATH first
 /// ("the user's own install wins"). With a bundle in the package that is the wrong way
 /// round: a random PATH <c>ffmpeg</c> may be a different major version or a GPL build, and
 /// the bundle is the one we pinned, license-vetted, and tested against. PATH stays as the
 /// escape hatch, which is what it is actually good for.</para>
 ///
 /// <para>The lgpl-<b>shared</b> variant is a licensing choice, not a packaging one: dynamic
 /// linking makes LGPL compliance "license text + source offer" with no static-relink
 /// (LGPL §6) material required. That means the <c>libav*.dll</c> family must sit in the
 /// same folder as the exe — Windows resolves them from the executable's own directory.</para>
 /// </summary>
 public sealed class FfmpegLocator : IFfmpegLocator
 {
    public const string FileName = "ffmpeg.exe";
-    /// <summary>Pinned BtbN LGPL-shared win64 build (immutable autobuild tag; see TASKS.md).</summary>
+    /// <summary>Sibling probe binary — bundled alongside ffmpeg so the media
-    public const string PinnedUrl =
+    /// frame-rate probe (<see cref="ytLive.Services.FfmpegFrameRateProbe"/>) can
-        "https://github.com/BtbN/FFmpeg-Builds/releases/download/autobuild-2026-08-09-13-03/ffmpeg-master-latest-win64-lgpl-shared.zip";
+    /// derive its path from the located ffmpeg directory.</summary>
    public const string ProbeFileName = "ffprobe.exe";
    /// <summary>Folder, relative to the app base directory, that the build copies the
    /// bundled build into. One folder for the exe and every DLL.</summary>
    public const string BundleFolderName = "ffmpeg";
    /// <summary>Base directory the bundle is resolved against. Injectable so tests can
    /// point at a temp tree; defaults to the running app's base directory.</summary>
    private readonly string _bundleRoot;
    private readonly string[] _searchDirs;
    private readonly string _toolsDir;
    private readonly Func<string, CancellationToken, Task<byte[]>> _downloader;
-    public FfmpegLocator(
+    public FfmpegLocator(string[]? searchDirs = null, string? bundleRoot = null)
        string[]? searchDirs = null,
        string? toolsDir = null,
        Func<string, CancellationToken, Task<byte[]>>? downloader = null)
    {
        _searchDirs = searchDirs ?? ParsePath();
-        _toolsDir = toolsDir ?? Path.Combine(
+        _bundleRoot = bundleRoot ?? AppContext.BaseDirectory;
            Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData), "ytLlive", "tools");
        _downloader = downloader ?? DefaultDownload;
    }
-    public async Task<string> LocateAsync(CancellationToken cancellationToken = default)
+    public Task<string> LocateAsync(CancellationToken cancellationToken = default)
    {
        var bundled = Path.Combine(_bundleRoot, BundleFolderName, FileName);
        if (IsUsable(bundled)) return Task.FromResult(bundled);
        foreach (var dir in _searchDirs)
        {
            if (string.IsNullOrEmpty(dir)) continue;
            var candidate = Path.Combine(dir, FileName);
-            if (File.Exists(candidate)) return candidate;
+            if (IsUsable(candidate)) return Task.FromResult(candidate);
        }
-        var cached = Path.Combine(_toolsDir, FileName);
+        // Deliberately loud. The previous cache-then-download ladder had a "found
-        if (File.Exists(cached) && new FileInfo(cached).Length > 0) return cached;
+        // something on disk" path that could satisfy a missing bundle with a stale copy,
-
+        // which is exactly the silent-drift a certification-gated dependency must not
-        try
+        // have. If the package forgot ffmpeg/, the app says so and stops.
-        {
+        throw new IOException(
-            var zip = await _downloader(PinnedUrl, cancellationToken).ConfigureAwait(false);
+            $"FFmpeg was not found. The bundled copy is missing from " +
-            if (zip.Length == 0)
+            $"'{Path.Combine(_bundleRoot, BundleFolderName)}' — this build is incomplete " +
-                throw new IOException($"FFmpeg download from {PinnedUrl} returned an empty payload.");
+            "(reinstall or re-fetch with scripts/fetch-ffmpeg.sh). Installing an LGPL-shared " +
-            Directory.CreateDirectory(_toolsDir);
+            "FFmpeg and putting 'ffmpeg' on PATH also works.");
            ExtractBinaries(zip, _toolsDir);
            return cached;
        }
        catch (Exception ex) when (ex is IOException or InvalidDataException or NotSupportedException)
        {
            AppLog.Write(ex, "FFmpeg locator: download/extract failed");
            throw;
        }
    }
-    /// <summary>
+    private static bool IsUsable(string path) =>
-    /// Extract <c>ffmpeg.exe</c> and every <c>*.dll</c> into <c>toolsDir</c> via a
+        File.Exists(path) && new FileInfo(path).Length > 0;
    /// staging directory, so a failed extract never leaves a partially-populated
    /// cache behind (the previous good cache stays until every move succeeds).
    /// </summary>
    private static void ExtractBinaries(byte[] zip, string toolsDir)
    {
        var staging = toolsDir + ".stage";
        if (Directory.Exists(staging)) Directory.Delete(staging, recursive: true);
        Directory.CreateDirectory(staging);
        try
        {
            using var stream = new MemoryStream(zip, writable: false);
            using var archive = new ZipArchive(stream, ZipArchiveMode.Read);
            var exe = archive.Entries.FirstOrDefault(
                    e => e.FullName.EndsWith("/" + FileName, StringComparison.OrdinalIgnoreCase))
                ?? throw new InvalidDataException($"The pinned FFmpeg archive does not contain {FileName}.");
            ExtractOne(exe, Path.Combine(staging, FileName));
            foreach (var entry in archive.Entries)
            {
                if (entry.FullName.EndsWith(".dll", StringComparison.OrdinalIgnoreCase))
                    ExtractOne(entry, Path.Combine(staging, Path.GetFileName(entry.FullName)));
            }
            foreach (var file in Directory.GetFiles(staging))
                File.Move(file, Path.Combine(toolsDir, Path.GetFileName(file)), overwrite: true);
        }
        finally
        {
            if (Directory.Exists(staging)) Directory.Delete(staging, recursive: true);
        }
    }
    private static void ExtractOne(ZipArchiveEntry entry, string destination)
    {
        var temp = destination + ".tmp";
        try
        {
            using (var source = entry.Open())
            using (var target = File.Create(temp))
                source.CopyTo(target);
            File.Move(temp, destination);
        }
        finally
        {
            if (File.Exists(temp)) File.Delete(temp);
        }
    }
    private static async Task<byte[]> DefaultDownload(string url, CancellationToken ct)
    {
        using var http = new HttpClient { Timeout = TimeSpan.FromMinutes(10) };
        return await http.GetByteArrayAsync(url, ct).ConfigureAwait(false);
    }
    private static string[] ParsePath()
    {
@@ -29,15 +29,92 @@ public sealed class FramePump : IDisposable
    private readonly Action<string>? _log;
    private readonly Func<TimeSpan, CancellationToken, Task> _pacingDelay;
    private readonly Func<(VideoFrame? Frame, SocialBarPosition Position)>? _socialBar;
    private readonly Func<VideoFrame?>? _alertTicker;
    private readonly Func<VideoFrame?>? _brandFlash;
    private readonly TransitionService? _transition;
-    private readonly Func<Scene?>? _fromSceneProvider;
+    private readonly SceneGraph? _sceneGraph;
    private readonly SceneCompositor _compositor = new();
    // Master-buffer scratch pool (take-4 starvation fix, slice 2 of 2): a fresh
    // 8.3MB byte[] every tick is ~500MB/s of LOH churn — GC stalls masquerading
    // as render cost. The pump pools ONLY buffers it handed out (reference-equality
    // set), so bake-cache / social-bar / static-cache frames are never touched;
    // SubmitFrameAsync copies the bytes to the encoder's stdin before returning,
    // so recycling after submit is safe (MyMistakes recipe).
    private readonly HashSet<byte[]> _ownedScratch = new(ReferenceEqualityComparer.Instance);
    private readonly List<byte[]> _freeScratch = new();
    private const int MaxScratchPooled = 4;
    private byte[] AcquireScratch(int size)
    {
        for (var i = _freeScratch.Count - 1; i >= 0; i--)
        {
            if (_freeScratch[i].Length != size) continue;
            var buffer = _freeScratch[i];
            _freeScratch.RemoveAt(i);
            return buffer;
        }
        var fresh = new byte[size];
        _ownedScratch.Add(fresh);
        return fresh;
    }
    private void ReleaseScratch(byte[]? buffer)
    {
        if (buffer == null || !_ownedScratch.Contains(buffer)) return;
        if (_freeScratch.Count >= MaxScratchPooled || _freeScratch.Contains(buffer)) return;
        _freeScratch.Add(buffer);
    }
    // Windows sleep quantum (take-9 finding, 2026-09-04): Task.Delay rounds every
    // request up to the system clock tick (~15.6ms default — learn.microsoft.com/en-us/
    // dotnet/api/system.threading.tasks.task.delay: "approximately 15 milliseconds on
    // Windows systems"), so a pacer requesting 3-15ms actually sleeps 15.6ms. Takes
    // 5-9 measured work ~25ms but period ~37ms: one padded wait per frame hid every
    // compositor improvement. Established media-app practice (game-loop/OBS canon —
    // stackoverflow.com/questions/5441464; and raise the resolution for the session —
    // learn.microsoft.com/en-us/windows/win32/api/timeapi/nf-timeapi-timebeginperiod):
    // timeBeginPeriod(1) while the pump runs, sleep only the BULK of the remainder,
    // and spin the last ~2ms across the deadline.
    [System.Runtime.InteropServices.DllImport("winmm.dll")]
    private static extern uint timeBeginPeriod(uint uMilliseconds);
    [System.Runtime.InteropServices.DllImport("winmm.dll")]
    private static extern uint timeEndPeriod(uint uMilliseconds);
    private static readonly long SpinTailTicks = System.Diagnostics.Stopwatch.Frequency * 2 / 1000; // 2ms
    private readonly object _gate = new();
    private IFfmpegEncoder? _encoder;
    private CancellationTokenSource? _cts;
    private Task? _pumpTask;
    private bool _started;
    private long _outputIndex;
    /// <summary>Captured by <see cref="ProbeRender"/> when a render exceeds ~20ms —
    /// the 2026-09-12 half-speed-render probe. Appended (once) to the next stats or
    /// stall line, then cleared.</summary>
    private string _renderDetail = "";
    /// <summary>C4 blit-on-change cache (2026-09-15): the FULL-render path (split=0
    /// when the live-capture backdrop sits at element 0, or no SceneGraph) re-composites
    /// the ENTIRE frame every tick even when no input changed — the ty-1841 take logged
    /// a render stall on EVERY iteration (totalMs 21-44, one composite per ~30ms while
    /// the content moved ~20 updates/s). The SceneGraph split can never help here: the
    /// backdrop is element 0 and must stay dynamic (a baked capture goes stale), so the
    /// cache lives at the pump: the last full-render output plus the input identity that
    /// produced it. Unchanged identity → ONE BlockCopy (~3ms) reuses the composite;
    /// changed identity → re-composite. The cache buffer is a SEPARATE long-lived array,
    /// never the scratch pool — the caller burns the frame counter and recycles the
    /// scratch AFTER RenderScene returns, so the cache is written from the rendered
    /// scratch BEFORE returning (pre-burn, pre-recycle). The identity mirror is
    /// <see cref="BuildFullRenderSignature"/>: it resolves the same frames the compositor
    /// will (same resolver seam), so a changed frame (new capture, new webcam, new chat
    /// raster) forces a re-render and an unchanged one never serves stale bytes. Internal
    /// counters feed the Good Dog test + the 5s cache detail in the stats line.</summary>
    private byte[]? _fullCachePixels;
    private bool _fullCacheValid;
    private ulong _lastFullSignature;
    internal long CacheHits;
    internal long CacheRenders;
    /// <summary>Forwards the encoder's parsed health — ship step 6 binds this to the bottom bar.</summary>
    public event EventHandler<StreamHealth>? HealthUpdated;
@@ -54,8 +131,10 @@ public sealed class FramePump : IDisposable
        Action<string>? log = null,
        Func<TimeSpan, CancellationToken, Task>? pacingDelay = null,
        Func<(VideoFrame? Frame, SocialBarPosition Position)>? socialBar = null,
        Func<VideoFrame?>? alertTicker = null,
        Func<VideoFrame?>? brandFlash = null,
        TransitionService? transition = null,
-        Func<Scene?>? fromSceneProvider = null)
+        SceneGraph? sceneGraph = null)
    {
        _sceneProvider = sceneProvider ?? throw new ArgumentNullException(nameof(sceneProvider));
        _frameResolver = frameResolver ?? throw new ArgumentNullException(nameof(frameResolver));
@@ -65,12 +144,19 @@ public sealed class FramePump : IDisposable
        _log = log;
        _pacingDelay = pacingDelay ?? ((delay, ct) => Task.Delay(delay, ct));
        _socialBar = socialBar;
        _alertTicker = alertTicker;
        _brandFlash = brandFlash;
        _transition = transition;
-        _fromSceneProvider = fromSceneProvider;
+        _sceneGraph = sceneGraph;
    }
    public bool IsRunning { get; private set; }
    /// <summary>The burned counter of the LAST frame submitted to the encoder. Stable
    /// across a tick's multiple resolver passes (it advances only at burn/submit, which
    /// happens AFTER render) — tests key per-tick content on it.</summary>
    internal long OutputIndex => _outputIndex;
    /// <summary>Never throws: failures are logged and surfaced via <see cref="Failed"/>,
    /// so the VM can fire-and-forget it from a sync command handler.</summary>
    public async Task StartAsync(CancellationToken cancellationToken = default)
@@ -107,8 +193,20 @@ public sealed class FramePump : IDisposable
            // synchronously on this thread before PumpAsync even returns.
            IsRunning = true;
            _cts = new CancellationTokenSource();
-            _pumpTask = PumpAsync(options, _cts.Token);
+            // The loop runs on the thread pool ON PURPOSE (take-8 finding, 2026-09-04):
-            _log?.Invoke($"FramePump started ({options.Width}×{options.Height} @ {options.Fps} fps)");
+            // Task.Run installs no SynchronizationContext, so every await continuation
            // stays off the UI dispatcher. Before this, the pump inherited the UI
            // thread's sync context (StartAsync is fired from a command handler), so
            // "render 22ms, wait 10ms" was the producer sitting in the dispatcher
            // queue behind the live preview it is meant to be independent of — the
            // stats quantum fix made the wait VISIBLE; this removes its cause.
            // OBS's video threads are dedicated for exactly this reason.
            _pumpTask = Task.Run(() => PumpAsync(options, _cts.Token));
            var scene = _sceneProvider();
            var comp = _compositorOptions();
            _log?.Invoke($"FramePump started ({options.Width}×{options.Height} @ {options.Fps} fps)" +
                         (scene != null ? $" scene='{scene.Name}'" : "") +
                         $" comp={comp.SourceRectWidth}x{comp.SourceRectHeight}");
        }
        catch (Exception ex)
        {
@@ -208,6 +306,8 @@ public sealed class FramePump : IDisposable
        {
            _log?.Invoke($"FramePump: dispose failed: {ex.Message}");
        }
        _freeScratch.Clear();
        _ownedScratch.Clear();
    }
    private async Task PumpAsync(EncoderOptions options, CancellationToken ct)
@@ -215,6 +315,121 @@ public sealed class FramePump : IDisposable
        var interval = TimeSpan.FromSeconds(1d / Math.Max(1, options.Fps));
        var lastTick = System.Diagnostics.Stopwatch.StartNew();
        // Deadline pacing (2026-09-03, take-3 fix): the frame interval is a DEADLINE,
        // not an afterthought sleep — the OBS libobs video-io.c pattern (researched
        // before coding; see https://github.com/obsproject/obs-studio/blob/master/
        // libobs/media-io/video-io.c). The old loop slept the FULL interval after
        // each render, so period = render + submit + interval: at take-3's 258ms
        // render that was 3.6fps stamped into a 60fps container — rawvideo stamps by
        // arrival, so 30 wall-seconds muxed as a 2.1s time-lapse, no error anywhere.
        var intervalTicks = Math.Max(1, (long)Math.Round(interval.TotalSeconds * System.Diagnostics.Stopwatch.Frequency));
        var nextTick = System.Diagnostics.Stopwatch.GetTimestamp();
        // Stage timing (2026-09-01, take two): rawvideo carries no per-frame
        // timestamps — ffmpeg stamps frames by ARRIVAL at the declared fps. A producer
        // slower than the declared rate yields a time-lapsed, short file (observed:
        // 39 frames in 27 wall-seconds ≈ 30x at 60fps) with no error anywhere.
        // Log the render/submit split every 5s so the next take names the stage.
        var renderSw = new System.Diagnostics.Stopwatch();
        var submitSw = new System.Diagnostics.Stopwatch();
        var waitSw = new System.Diagnostics.Stopwatch();
        // Resolve-vs-composite split (2026-09-04, take-6 ambiguity): "render" was a
        // black box — the stats line now reports resolver time separately so a take
        // names the stage (get-frame vs blit) instead of feeding another guess.
        var resolveSw = new System.Diagnostics.Stopwatch();
        long renderTicks = 0, submitTicks = 0, resolveTicks = 0, waitTicks = 0;
        long socialBarTicks = 0, tickerTicks = 0, flashTicks = 0, acquireTicks = 0;
        long worstRender = 0, worstSubmit = 0;
        int statFrames = 0;
        int stalls = 0;
        long lastCacheHits = 0, lastCacheRenders = 0;
        var statsNext = DateTime.UtcNow + TimeSpan.FromSeconds(5);
        // bool _loggedStartDetail = false;
        // Real-render accounting (UNIT 0, 2026-10-05): every average above was
        // divided by statFrames — the number of frames SUBMITTED, which deadline
        // padding always fills to the full target even when the renderer only
        // produced a fifth of them. A 60fps container therefore reported "300/300
        // frames, avg render 12ms" while the source actually fed it 60 distinct
        // images. Render cost is now divided by the render count, and the render
        // count is reported beside the submit count — the two numbers side by side
        // ARE the duplicate-on-lag ratio, which is the only honest reading of how
        // much of the stream is a repeat.
        int statRenders = 0;
        // Webcam cadence (UNIT 0, 2026-10-05): the pump sees each element's resolved
        // frame, and VideoFrame.Epoch is the webcam ring's monotonic generation — so a
        // NEW epoch means the webcam actually delivered something new between two of
        // our ticks. This is the counterpart to MediaCaptureFrameSource's arrivals
        // line: it measures what reached the OUTPUT, not what the camera produced. If
        // the camera reports 30/s and this reports 25/s, the loss is between them.
        var webcamCadence = new Helpers.FrameCadence();
        var seenWebcamEpochs = new HashSet<long>();
        void ReportStats()
        {
            if (DateTime.UtcNow < statsNext) return;
            var target = 5d / interval.TotalSeconds; // frames expected per window
            IFfmpegEncoder? encoder;
            lock (_gate) encoder = _encoder;
            var dropped = encoder == null ? 0 : encoder.DroppedFrames;
            var detail = _renderDetail;
            _renderDetail = "";
            var cacheDetail = "";
            if (statFrames > 0)
            {
                // C4 window detail: rendered composites (R) vs cache reuses (H) since the
                // last report — hard numeric proof the blit-on-change cache engaged.
                var hits = CacheHits - lastCacheHits;
                var renders = CacheRenders - lastCacheRenders;
                lastCacheHits = CacheHits;
                lastCacheRenders = CacheRenders;
                if (hits > 0 || renders > 0) cacheDetail = $", cache {renders}R/{hits}H";
            }
            double freq = System.Diagnostics.Stopwatch.Frequency;
            _log?.Invoke(statFrames == 0
                ? "FramePump stats: NO frames produced in 5s (loop stalled?)" + (detail.Length > 0 ? " | " + detail : "")
                : $"FramePump stats: {statFrames}/{target:F0} frames per 5s from {statRenders} renders, " +
                  $"avg render {renderTicks / freq * 1000 / Math.Max(1, statRenders):F1}ms " +
                  $"(resolve {resolveTicks / freq * 1000 / Math.Max(1, statRenders):F1}, " +
                  $"social {socialBarTicks / freq * 1000 / Math.Max(1, statRenders):F2}ms, " +
                  $"ticker {tickerTicks / freq * 1000 / Math.Max(1, statRenders):F2}ms, " +
                  $"flash {flashTicks / freq * 1000 / Math.Max(1, statRenders):F2}ms, " +
                  $"acq {acquireTicks / freq * 1000 / Math.Max(1, statRenders):F2}ms), " +
                  $"avg submit {submitTicks / freq * 1000 / statFrames:F1}ms, "
                  + $"avg wait {waitTicks / freq * 1000 / Math.Max(1, statRenders):F1}ms, "
                  + $"worst render {worstRender / freq * 1000:F1}ms, "
                  + $"worst submit {worstSubmit / freq * 1000:F1}ms, "
                  + $"dropped {dropped}, stalls {stalls}{cacheDetail}, {webcamCadence.Summarize().Describe("webcam")}"
                  + (detail.Length > 0 ? " | " + detail : ""));
            worstRender = 0;
            worstSubmit = 0;
            renderTicks = submitTicks = resolveTicks = waitTicks = 0;
            socialBarTicks = tickerTicks = flashTicks = acquireTicks = 0;
            statFrames = 0;
            statRenders = 0;
            stalls = 0;
            webcamCadence.Reset();
            seenWebcamEpochs.Clear();
            statsNext = DateTime.UtcNow + TimeSpan.FromSeconds(5);
        }
        // One wrapper shared by every render of the run — resolve time accumulates
        // inside the render measurement, and the stats line reports the split.
        timeBeginPeriod(1); // pairs with timeEndPeriod in the finally — see field note
        var previousGcMode = System.Runtime.GCSettings.LatencyMode;
        System.Runtime.GCSettings.LatencyMode = System.Runtime.GCLatencyMode.SustainedLowLatency;
        VideoFrame? TimedResolver(SceneElement element)
        {
            resolveSw.Restart();
            var frame = _frameResolver(element);
            resolveSw.Stop();
            resolveTicks += resolveSw.ElapsedTicks;
            if (element.IsWebcam && frame != null && seenWebcamEpochs.Add(frame.Epoch))
                webcamCadence.Add(System.Diagnostics.Stopwatch.GetTimestamp());
            return frame;
        }
        try
        {
            while (!ct.IsCancellationRequested)
@@ -222,6 +437,7 @@ public sealed class FramePump : IDisposable
                var scene = _sceneProvider();
                if (scene != null)
                {
                    var iterStart = System.Diagnostics.Stopwatch.GetTimestamp();
                    var compositorOptions = _compositorOptions();
                    VideoFrame? socialBarFrame = null;
                    var socialBarTop = 0;
@@ -235,30 +451,125 @@ public sealed class FramePump : IDisposable
                                : compositorOptions.SourceRectHeight - barFrame.Height;
                    }
                    var sw = System.Diagnostics.Stopwatch.StartNew();
                    VideoFrame? tickerFrame = _alertTicker?.Invoke();
                    tickerTicks += sw.ElapsedTicks;
                    sw.Restart();
                    VideoFrame? flashFrame = _brandFlash?.Invoke();
                    flashTicks += sw.ElapsedTicks;
                    sw.Restart();
                    var (barFrame2, position2) = (_socialBar == null ? (null, SocialBarPosition.Bottom) : _socialBar());
                    socialBarFrame = barFrame2;
                    socialBarTop = barFrame2 == null ? 0 : (position2 == SocialBarPosition.Top ? 0 : compositorOptions.SourceRectHeight - barFrame2.Height);
                    socialBarTicks += sw.ElapsedTicks;
                    VideoFrame frame;
-                    if (_transition is { Active: true } transition && _fromSceneProvider != null)
+                    var scratchSize = compositorOptions.SourceRectWidth
                        * compositorOptions.SourceRectHeight * 4;
                    renderSw.Restart();
                    sw.Restart();
                    var scratch = AcquireScratch(scratchSize);
                    acquireTicks += sw.ElapsedTicks;
                    frame = RenderScene(scene, compositorOptions, socialBarFrame, socialBarTop, tickerFrame, flashFrame, scratch, TimedResolver);
                    if (_transition is { Active: true } transition)
                    {
-                        var fromScene = _fromSceneProvider();
+                        frame = transition.BlendFrame(frame);
                        var fromFrame = fromScene != null
                            ? _compositor.Render(fromScene, _frameResolver, null, compositorOptions, socialBarFrame, socialBarTop)
                            : _compositor.Render(scene, _frameResolver, null, compositorOptions, socialBarFrame, socialBarTop);
                        var toFrame = _compositor.Render(scene, _frameResolver, null, compositorOptions, socialBarFrame, socialBarTop);
                        frame = transition.BlendFrame(toFrame);
                        transition.Tick(lastTick.Elapsed.TotalMilliseconds);
                        lastTick.Restart();
                    }
                    else
                    {
                        frame = _compositor.Render(scene, _frameResolver, null, compositorOptions, socialBarFrame, socialBarTop);
                        lastTick.Restart();
                    }
                    // Restarted EVERY frame (transition or not): a transition begun
                    // after idle must not inherit a giant ElapsedMs and complete
                    // instantly on its first Tick.
                    lastTick.Restart();
                    renderSw.Stop();
                    renderTicks += renderSw.ElapsedTicks;
                    if (renderSw.ElapsedTicks > worstRender) worstRender = renderSw.ElapsedTicks;
                    statRenders++;
                    IFfmpegEncoder? encoder;
                    lock (_gate) encoder = _encoder;
                    if (encoder == null) break;
-                    await encoder.SubmitFrameAsync(frame, ct);
+
                    // Deadline pacing, OBS duplicate-on-lag (slice 15): emit ONE frame per
                    // deadline slot — a fresh composite when the render kept up, a REPEAT
                    // of this iteration's latest composite for every slot the render
                    // overran. The OBS model never leaves a wall-time hole: libobs
                    // media-io/video-io.c runs on its own clock and duplicates the latest
                    // frame when the video thread lags, logging "lagged frames due to
                    // rendering lag/stalls" — never skipped time (docs.obsproject.com/
                    // backend-design: "If the video frame queue is full, it will duplicate
                    // the last frame"). Slice 10 chose the opposite for freshness: an
                    // overrun SKIPPED the missed slots, so a 60fps-authoring pump emitting
                    // one frame per 35ms overrun authored ~1.7x playback (ty-1726: 163
                    // video frames for 2.93s of audio) and ended the video 0.22s before the
                    // audio tail. Counting duplicates instead of skips keeps recording
                    // duration == wall duration (no acceleration, no audio tail cut) at the
                    // cost of a short judder during a stall — the accepted trade. The burst
                    // is microseconds (the enqueue never blocks, and the loop is clamped to
                    // deadlineNow) so it can't smear the way the take-9 blocking burst did.
                    var deadlineNow = System.Diagnostics.Stopwatch.GetTimestamp();
                    while (!ct.IsCancellationRequested && deadlineNow >= nextTick)
                    {
                        // Burned-in frame counter (slice 10 judge): a clock-independent
                        // pacing witness burned literally into the composite. Decode the
                        // recording and read the bottom-right strip: the number must
                        // advance +1 per authored frame and jump only by counted drops
                        // (queue overflow). Burned here — on the buffer finally submitted,
                        // which the enqueue's snapshot copies before the next iteration
                        // rewrites it — so every file frame carries its own index and a
                        // fast-render iteration that submitted nothing leaves no phantom
                        // gap (the slice-10 unconditional bump before the gate could).
                        _outputIndex++;
                        BurnFrameIndex(frame.BgraPixels, frame.Width, frame.Height, _outputIndex);
                        submitSw.Restart();
                        await encoder.SubmitFrameAsync(frame, ct);
                        submitSw.Stop();
                        statFrames++;
                        submitTicks += submitSw.ElapsedTicks;
                        if (submitSw.ElapsedTicks > worstSubmit) worstSubmit = submitSw.ElapsedTicks;
                        nextTick += intervalTicks;
                    }
                    // SubmitFrameAsync copied the bytes into the encoder's queue — the
                    // tick's buffers are recyclable once the enqueue snapshot them.
                    // The free-list Contains guard keeps the Cut path (BlendFrame
                    // returns toFrame itself, aliasing scratch) safe.
                    ReleaseScratch(frame.BgraPixels);
                    ReleaseScratch(scratch);
                    // Sleep the BULK of the remainder, SPIN the 2ms tail — never hand
                    // a sub-tick remainder to the sleep quantum (the timeBeginPeriod
                    // note). If the renderer already ate the budget there is nothing
                    // left to sleep and the loop renders the next frame straight away.
                    waitSw.Restart();
                    var ahead = nextTick - System.Diagnostics.Stopwatch.GetTimestamp();
                    if (ahead > SpinTailTicks)
                        await _pacingDelay(TimeSpan.FromSeconds(
                            (ahead - SpinTailTicks) / (double)System.Diagnostics.Stopwatch.Frequency), ct);
                    while (!ct.IsCancellationRequested
                           && System.Diagnostics.Stopwatch.GetTimestamp() < nextTick)
                        Thread.SpinWait(400);
                    waitSw.Stop();
                    waitTicks += waitSw.ElapsedTicks;
                    // Stall logger (slice 10): an iteration spanning more than two full
                    // intervals is the old bug's fingerprint — name the stage instead of
                    // guessing. With the queue, submit should be ~1ms, so a stall here
                    // means RENDER or RESOLVE (the stage terms of the last take).
                    var iterWall = System.Diagnostics.Stopwatch.GetTimestamp() - iterStart;
                    if (iterWall > 2 * intervalTicks)
                    {
                        stalls++;
                        var detail = _renderDetail;
                        _renderDetail = "";
                        _log?.Invoke($"FramePump stall: iteration {iterWall / (double)System.Diagnostics.Stopwatch.Frequency * 1000:F0}ms " +
                            $"(> 2× the {interval.TotalMilliseconds:F0}ms interval): worst render " +
                            $"{worstRender / (double)System.Diagnostics.Stopwatch.Frequency * 1000:F0}ms, worst submit " +
                            $"{worstSubmit / (double)System.Diagnostics.Stopwatch.Frequency * 1000:F0}ms, dropped {encoder.DroppedFrames}" +
                            (detail.Length > 0 ? " | " + detail : ""));
                    }
                    ReportStats();
                }
                await _pacingDelay(interval, ct);
            }
        }
        catch (OperationCanceledException)
@@ -281,12 +592,310 @@ public sealed class FramePump : IDisposable
        }
        finally
        {
            System.Runtime.GCSettings.LatencyMode = previousGcMode;
            timeEndPeriod(1);
            lock (_gate) IsRunning = false;
        }
    }
    private void OnHealthUpdated(object? sender, StreamHealth health) => HealthUpdated?.Invoke(this, health);
    /// <summary>Render a scene, using the baked-crust optimization when a <see cref="SceneGraph"/>
    /// is wired in: bake/cache the static layers below the split point, then composite the
    /// dynamic/above-split layers per frame. Without a SceneGraph, falls back to a full render
    /// (identical output — see SceneCompositorTests). <paramref name="scratch"/> is a pooled
    /// master buffer when supplied; the fully-static path returns the bake-cache frame itself
    /// (never pooled — the release side checks owned-by-reference).</summary>
    private VideoFrame RenderScene(
        Scene scene,
        CompositorOptions options,
        VideoFrame? socialBarFrame,
        int socialBarTop,
        VideoFrame? tickerFrame,
        VideoFrame? flashFrame,
        byte[]? scratch = null,
        Func<SceneElement, VideoFrame?>? resolver = null)
    {
        resolver ??= _frameResolver;
        if (_sceneGraph == null)
        {
            var sw = System.Diagnostics.Stopwatch.StartNew();
            var frame = RenderFull(scene, options, socialBarFrame, socialBarTop, tickerFrame, flashFrame, scratch, resolver);
            ProbeRender("full-no-graph", scene, -1, sw.ElapsedMilliseconds, 0);
            return frame;
        }
        var split = _sceneGraph.GetSplitPoint(scene);
        if (split == scene.Elements.Count)
        {
            // Fully static scene: bake once, reuse.
            var sw = System.Diagnostics.Stopwatch.StartNew();
            var baked = _sceneGraph.GetBakedBase(scene, _frameResolver, _compositorOptions);
            if (baked != null)
            {
                // BUG (pre-existing, found while wiring the branding credit 2026-09-26):
                // this path returned the stretched bake and silently DROPPED the social
                // bar and the alert ticker. Overlay() copies before blitting, so the
                // cached bake is not mutated and the flash still cannot get sticky in it.
                if (socialBarFrame != null || tickerFrame != null || flashFrame != null)
                {
                    var withOverlays = baked;
                    if (flashFrame != null) withOverlays = SceneCompositor.Overlay(withOverlays, options, flashFrame, 0, 0);
                    if (tickerFrame != null) withOverlays = SceneCompositor.Overlay(withOverlays, options, tickerFrame, tickerFrame.OriginX, tickerFrame.OriginY);
                    if (socialBarFrame != null) withOverlays = SceneCompositor.Overlay(withOverlays, options, socialBarFrame, socialBarTop, 0);
                    baked = withOverlays;
                }
                var stretched = StretchMath.BilinearScale(baked, options.OutputWidth, options.OutputHeight);
                ProbeRender("fully-static", scene, split, sw.ElapsedMilliseconds, (int)sw.ElapsedMilliseconds);
                return stretched;
            }
        }
        var swBase = System.Diagnostics.Stopwatch.StartNew();
        var baseFrame = _sceneGraph.GetBakedBase(scene, _frameResolver, _compositorOptions);
        if (baseFrame != null)
        {
            var frame = SceneCompositor.CompositeLayers(
                baseFrame, scene, split, resolver, options, socialBarFrame, socialBarTop, flashFrame: flashFrame, tickerFrame: tickerFrame, scratch: scratch);
            ProbeRender("base+layers", scene, split, swBase.ElapsedMilliseconds, 0);
            return frame;
        }
        // No static base (first layer is dynamic or empty scene) — full render.
        var swFull = System.Diagnostics.Stopwatch.StartNew();
        var frame2 = RenderFull(scene, options, socialBarFrame, socialBarTop, tickerFrame, flashFrame, scratch, resolver);
        ProbeRender("full-render", scene, split, swFull.ElapsedMilliseconds, 0);
        return frame2;
    }
    /// <summary>The full-render path (no SceneGraph, or no static base) wrapped in the
    /// C4 blit-on-change cache: when every resolved input plus every element's
    /// layout/visual bits match the last composite, reuse it with one BlockCopy instead
    /// of re-compositing. Mirror the compositor's resolution <i>before</i> deciding so a
    /// hit costs ~3ms of pure copy and a miss costs exactly the old full render.</summary>
    private VideoFrame RenderFull(
        Scene scene, CompositorOptions options, VideoFrame? socialBarFrame, int socialBarTop,
        VideoFrame? tickerFrame, VideoFrame? flashFrame,
        byte[]? scratch, Func<SceneElement, VideoFrame?> resolver)
    {
        // 1:1 guard: the cache stores the OUTPUT bytes and scratch is source-sized —
        // at 1:1 they are the same buffer size. Off-size tiers (a vertical 1080×1920
        // tier, an H264-1080p tier) fall back to a per-tick full render; the deployed
        // config is master-sized and caching a per-tick fresh scale buffer is the known
        // vertical-tier follow-up (see ai.md), not silently baked here.
        var useCache = scratch != null && options.SourceRectWidth == options.OutputWidth
            && options.SourceRectHeight == options.OutputHeight;
        var signature = useCache
            ? BuildFullRenderSignature(scene, options, socialBarFrame, socialBarTop, tickerFrame, flashFrame, resolver)
            : 0UL;
        if (useCache && _fullCacheValid && signature == _lastFullSignature
            && _fullCachePixels!.Length == scratch!.Length)
        {
            Buffer.BlockCopy(_fullCachePixels, 0, scratch, 0, scratch.Length);
            CacheHits++;
            return new VideoFrame(options.SourceRectWidth, options.SourceRectHeight, scratch);
        }
        var rendered = _compositor.Render(scene, resolver, flashFrame, options, socialBarFrame, socialBarTop, scratch: scratch, tickerFrame: tickerFrame);
        CacheRenders++;
        if (useCache)
        {
            var pixels = rendered.BgraPixels;
            if (_fullCachePixels == null || _fullCachePixels.Length != pixels.Length)
                _fullCachePixels = new byte[pixels.Length];
            // PRE-burn / PRE-recycle: the caller burns the counter and recycles this
            // scratch after RenderScene returns — the cache keeps a clean copy, and the
            // burn on the next hit writes to a FRESH scratch copy, never the cache.
            Buffer.BlockCopy(pixels, 0, _fullCachePixels, 0, pixels.Length);
            _lastFullSignature = signature;
            _fullCacheValid = true;
        }
        else
        {
            _fullCacheValid = false; // size changed — never reuse a wrong-size buffer
        }
        return rendered;
    }
    /// <summary>Hash the complete set of inputs the compositor's FULL render consumes:
    /// the crop/output dimensions, the social bar, and — in element order, mirroring
    /// <c>SceneCompositor.Render</c>'s iteration — every element's layout/visual fields
    /// plus the frame each one resolves (through the SAME resolver seam the render will
    /// use). A changed frame (new capture, new webcam Epoch, new chat raster) changes the
    /// hash → re-composite; an unchanged one reuses the cache. Buffer-array identity +
    /// Epoch + CropBounds is the compositor's own paste-key shape — producers hand out
    /// fresh immutable arrays, or recycled-ring arrays whose monotonic Epoch
    /// distinguishes generations (the capture take-11 fix), so address-identity alone is
    /// never trusted to key recycled content.</summary>
    private static ulong BuildFullRenderSignature(
        Scene scene, CompositorOptions options, VideoFrame? socialBarFrame, int socialBarTop,
        VideoFrame? tickerFrame,
        VideoFrame? flashFrame,
        Func<SceneElement, VideoFrame?> resolver)
    {
        var h = 14695981039346656037UL; // FNV-1a offset basis
        h = Mix(h, (ulong)options.SourceRectX);
        h = Mix(h, (ulong)options.SourceRectY);
        h = Mix(h, (ulong)options.SourceRectWidth);
        h = Mix(h, (ulong)options.SourceRectHeight);
        h = Mix(h, (ulong)options.OutputWidth);
        h = Mix(h, (ulong)options.OutputHeight);
        h = Mix(h, (ulong)socialBarTop);
        if (socialBarFrame != null) h = MixFrame(h, socialBarFrame);
        else h = Mix(h, 0xFFFFFFFFFFFFFFFFUL);
        if (tickerFrame != null) h = MixFrame(h, tickerFrame);
        else h = Mix(h, 0xFFFFFFFFFFFFFFFFUL);
        // BrandFlashPresenter recycles one buffer and bumps Epoch every read, so this
        // invalidates the cache on every tick of a credit — a cached frame would freeze
        // the fade and pin a stale spot.
        if (flashFrame != null) h = MixFrame(h, flashFrame);
        else h = Mix(h, 0xFFFFFFFFFFFFFFFFUL);
        var backdropResolved = false;
        foreach (var element in scene.Elements)
        {
            h = Mix(h, (ulong)System.Runtime.CompilerServices.RuntimeHelpers.GetHashCode(element));
            h = Mix(h, element.IsVisible ? 1UL : 0UL);
            h = MixDouble(h, element.X);
            h = MixDouble(h, element.Y);
            h = MixDouble(h, element.Width);
            h = MixDouble(h, element.Height);
            h = MixDouble(h, element.Opacity);
            h = Mix(h, (ulong)element.ClipShape);
            h = Mix(h, element.IsMirrored ? 1UL : 0UL);
            h = Mix(h, (ulong)element.BorderWidth);
            h = MixDouble(h, element.BorderOpacity);
            if (element.TryGetBorderColor(out var bcR, out var bcG, out var bcB))
                h = Mix(h, (ulong)((bcR << 16) | (bcG << 8) | bcB));
            else
                h = Mix(h, 0UL);
            // Mirror the compositor's per-element frame resolution EXACTLY, so the hash
            // reacts to the same frames a render uses and never to a frame a render
            // ignores (a false-positive change only wastes one render; a false NEGATIVE
            // would serve stale bytes — that is what this mirror prevents).
            VideoFrame? frame = null;
            if (element is Source { IsBackground: true })
            {
                h = Mix(h, 1UL); // the live backdrop — first visible one is resolved, once
                if (element.IsVisible && !backdropResolved)
                {
                    frame = resolver(element);
                    backdropResolved = true;
                }
            }
            else if (element is Source { Type: SourceType.TextOverlay })
            {
                h = Mix(h, 2UL); // skipped kind — never resolved by the compositor
            }
            else if (element is Source { Type: SourceType.Background })
            {
                h = Mix(h, 3UL); // background image — resolved even when invisible (Render does)
                frame = resolver(element);
            }
            else
            {
                h = Mix(h, 4UL); // regular layer — resolved only when visible
                if (element.IsVisible) frame = resolver(element);
            }
            if (frame != null) h = MixFrame(h, frame);
            else h = Mix(h, 0UL);
        }
        return h;
    }
    private static ulong Mix(ulong h, ulong v) => (h ^ v) * 0x9E3779B97F4A7C15UL;
    private static ulong MixDouble(ulong h, double v)
        => Mix(h, unchecked((ulong)BitConverter.DoubleToInt64Bits(v)));
    private static ulong MixFrame(ulong h, VideoFrame frame)
    {
        h = Mix(h, (ulong)System.Runtime.CompilerServices.RuntimeHelpers.GetHashCode(frame.BgraPixels));
        h = Mix(h, (ulong)frame.Epoch);
        h = Mix(h, (ulong)frame.Width);
        h = Mix(h, (ulong)frame.Height);
        if (frame.CropBounds is { } cb)
        {
            h = Mix(h, (ulong)cb.X);
            h = Mix(h, (ulong)cb.Y);
            h = Mix(h, (ulong)cb.W);
            h = Mix(h, (ulong)cb.H);
        }
        else
        {
            h = Mix(h, 0xFFFFFFFFFFFFFFFFUL);
        }
        return h;
    }
    /// <summary>2026-09-12 half-speed-render probe: the pump only produces ~27fps
    /// (render ~35ms vs the 16.7ms deadline), and rawvideo muxes at the DECLARED fps,
    /// so every take muxes at ~half its wall length (the truncation complaint). This
    /// names WHICH compositor path ate the slow frame so the fix targets the real
    /// stage. Records only when a frame takes ≥20ms (or carries the previous detail).</summary>
    private void ProbeRender(string path, Scene scene, int split, long totalMs, int bakeMs)
    {
        if (totalMs < 20 && _renderDetail.Length == 0) return;
        var dynamics = 0;
        foreach (var e in scene.Elements)
            if (e.Kind == ElementKind.Dynamic) dynamics++;
        _renderDetail = $"render={path} split={split} elements={scene.Elements.Count} dynamic={dynamics}" +
                        (bakeMs > 0 ? $" bakeMs={bakeMs}" : "") + $" totalMs={totalMs}";
    }
    // Dot-matrix digits (5×7, one row per raster line, '1' = lit) burned into the
    // bottom-right of every composite. Basic OCR-safe shapes, sized so the strip is
    // a 36×8 white box in the corner of a 1920×1080 frame — readable with a zoomed
    // player, invisible at normal size.
    private static readonly string[][] DigitGlyphs =
    {
        new[] { "01110","10001","10001","10001","10001","10001","01110" }, // 0
        new[] { "00100","01100","00100","00100","00100","00100","01110" }, // 1
        new[] { "01110","10001","00001","00010","00100","01000","11111" }, // 2
        new[] { "11111","00001","00010","00110","00001","10001","01110" }, // 3
        new[] { "00010","00110","01010","10010","11111","00010","00010" }, // 4
        new[] { "11111","10000","11110","00001","00001","10001","01110" }, // 5
        new[] { "01110","10001","10000","11110","10001","10001","01110" }, // 6
        new[] { "11111","00001","00010","00100","01000","01000","01000" }, // 7
        new[] { "01110","10001","10001","01110","10001","10001","01110" }, // 8
        new[] { "01110","10001","10001","01111","00001","10001","01110" }, // 9
    };
    private static void BurnFrameIndex(byte[] bgra, int width, int height, long index)
    {
        const int digitW = 5, digitH = 7, gap = 1, margin = 2, digitCount = 6;
        var stripW = digitCount * (digitW + gap) - gap;
        var left = width - margin - stripW;
        var top = height - margin - digitH;
        // Solid white box under the digits — the underlying scene can be anything.
        for (var y = top; y < top + digitH; y++)
            for (var x = left; x < left + stripW; x++)
            {
                var i = (y * width + x) * 4;
                bgra[i] = 255;
                bgra[i + 1] = 255;
                bgra[i + 2] = 255;
            }
        var text = index.ToString("D6");
        for (var d = 0; d < digitCount; d++)
        {
            var glyph = DigitGlyphs[text[d] - '0'];
            for (var row = 0; row < digitH; row++)
                for (var col = 0; col < digitW; col++)
                {
                    if (glyph[row][col] != '1') continue;
                    var i = ((top + row) * width + (left + d * (digitW + gap) + col)) * 4;
                    bgra[i] = 0;
                    bgra[i + 1] = 0;
                    bgra[i + 2] = 0;
                }
        }
    }
    private void OnProcessFailed(object? sender, string message)
    {
        _log?.Invoke($"FramePump: encoder process failed: {message}");
@@ -22,4 +22,9 @@ public interface IFfmpegEncoder : IDisposable
    Task StartAsync(EncoderOptions options, CancellationToken cancellationToken = default);
    Task SubmitFrameAsync(VideoFrame frame, CancellationToken cancellationToken = default);
    Task StopAsync(CancellationToken cancellationToken = default);
    /// <summary>Frames dropped by the encoder's bounded queue since start (the encoder
    /// lagging the real-time capture rate). Zero in a healthy session; fed to the pump's
    /// stats and mirrored by gaps in the burned-in frame counter of the recording.</summary>
    int DroppedFrames { get; }
 }
@@ -0,0 +1,36 @@
 using System.Diagnostics;
 using System.IO;
 namespace ytLive.Services;
 /// <summary>
 /// The real <see cref="IDecodeProcess"/>: a <see cref="Process"/> with stdout
 /// redirected as raw bytes for reading <c>rawvideo</c> frames. Constructed by
 /// <see cref="MediaVideoSource"/> for the media-file decoder subprocess.
 /// </summary>
 public sealed class FfmpegDecodeProcess : IDecodeProcess
 {
    private readonly Process _process;
    public FfmpegDecodeProcess() => _process = new Process { EnableRaisingEvents = true };
    public void Start(ProcessStartInfo startInfo)
    {
        _process.StartInfo = startInfo;
        _process.Start();
    }
    public Stream StandardOutput => _process.StandardOutput.BaseStream;
    public bool HasExited => _process.HasExited;
    public int ExitCode => _process.ExitCode;
    public void Kill()
    {
        if (!_process.HasExited) _process.Kill();
    }
    public Task WaitForExitAsync(CancellationToken cancellationToken = default)
        => _process.WaitForExitAsync(cancellationToken);
    public void Dispose() => _process.Dispose();
 }
@@ -0,0 +1,53 @@
 using System.Globalization;
 namespace ytLive.Services;
 /// <summary>
 /// TASK 21 (slice 2): parses the native frame rate of a video from ffprobe
 /// <c>-show_entries stream=avg_frame_rate,r_frame_rate</c> output, which reports
 /// each as a rational like <c>30/1</c> or <c>60000/1001</c> (or <c>0/0</c> when
 /// unknown). Prefers <c>avg_frame_rate</c> (the true display rate over the whole
 /// file, correct for VFR) and falls back to <c>r_frame_rate</c> (the container/
 /// codec rate). Pure: no ffprobe, no I/O, unit-testable.
 /// </summary>
 public static class FfmpegFrameRateParser
 {
    public static double? ParseFrameRate(string probeOutput)
    {
        foreach (var key in new[] { "avg_frame_rate=", "r_frame_rate=" })
        {
            var value = FindValue(probeOutput, key);
            if (value is not null && TryParseRational(value, out var fps))
                return fps;
        }
        return null;
    }
    /// <summary>The trimmed value of the first line beginning with <paramref name="key"/>.</summary>
    private static string? FindValue(string text, string key)
    {
        foreach (var line in text.Split('\n'))
        {
            var trimmed = line.Trim();
            if (trimmed.StartsWith(key, StringComparison.Ordinal))
                return trimmed.Substring(key.Length).Trim();
        }
        return null;
    }
    /// <summary>Parses <c>v</c> as <c>N</c> (integer) or <c>N/M</c> (rational) into
    /// a frames-per-second double. <c>0</c> and <c>0/M</c> count as unknown.</summary>
    private static bool TryParseRational(string value, out double fps)
    {
        fps = 0;
        var parts = value.Split('/');
        if (parts.Length == 0 || !int.TryParse(parts[0], NumberStyles.None, CultureInfo.InvariantCulture, out var num))
            return false;
        var den = 1;
        if (parts.Length > 1 && !int.TryParse(parts[1], NumberStyles.None, CultureInfo.InvariantCulture, out den))
            return false;
        if (num <= 0 || den <= 0) return false;
        fps = (double)num / den;
        return true;
    }
 }
@@ -0,0 +1,67 @@
 using System.Diagnostics;
 using System.IO;
 using ytLive.Services.Encoder;
 namespace ytLive.Services;
 /// <summary>
 /// TASK 21 (slice 2): resolves the native frame rate of a media file so the
 /// decoder can pace frames to real time. Seam so <see cref="MediaVideoSource"/>
 /// never touches ffprobe directly and tests can fake the whole probe.
 /// </summary>
 public interface IFrameRateProbe
 {
    /// <summary>Native video FPS for <paramref name="path"/>, or null when unknown
    /// (no video stream, ffprobe unavailable, unparsable).</summary>
    Task<double?> ProbeAsync(string path, CancellationToken cancellationToken = default);
 }
 /// <summary>
 /// Default probe: locates ffmpeg (via <see cref="IFfmpegLocator"/>), derives the
 /// sibling <c>ffprobe.exe</c> from its directory, and asks ffprobe for the
 /// <c>avg_frame_rate</c>/<c>r_frame_rate</c>. Reuses the binary-stdout
 /// <see cref="IDecodeProcess"/> seam for the subprocess (ffprobe text is read from
 /// the same raw stdout). Returns null (no pacing) if ffprobe is unavailable.
 /// </summary>
 public sealed class FfmpegFrameRateProbe : IFrameRateProbe
 {
    private readonly IFfmpegLocator _locator;
    private readonly Func<IDecodeProcess> _probeProcessFactory;
    public FfmpegFrameRateProbe(IFfmpegLocator locator, Func<IDecodeProcess> probeProcessFactory)
    {
        _locator = locator;
        _probeProcessFactory = probeProcessFactory;
    }
    public async Task<double?> ProbeAsync(string path, CancellationToken cancellationToken = default)
    {
        if (string.IsNullOrWhiteSpace(path)) return null;
        var ffmpegPath = await _locator.LocateAsync(cancellationToken).ConfigureAwait(false);
        var ffprobePath = Path.Combine(Path.GetDirectoryName(ffmpegPath) ?? string.Empty, "ffprobe.exe");
        if (!File.Exists(ffprobePath)) return null;
        var startInfo = new ProcessStartInfo
        {
            FileName = ffprobePath,
            Arguments =
                $"-v error -select_streams v:0 " +
                $"-show_entries stream=avg_frame_rate,r_frame_rate " +
                $"-of default=noprint_wrappers=1 \"{path}\"",
            UseShellExecute = false,
            RedirectStandardOutput = true,
            RedirectStandardError = true,
            CreateNoWindow = true,
        };
        using var process = _probeProcessFactory();
        process.Start(startInfo);
        string output;
        using (var reader = new StreamReader(process.StandardOutput))
            output = reader.ReadToEnd();
        await process.WaitForExitAsync(cancellationToken).ConfigureAwait(false);
        return FfmpegFrameRateParser.ParseFrameRate(output);
    }
 }
@@ -0,0 +1,90 @@
 using System;
 namespace ytLive.Services;
 /// <summary>
 /// A depth-bounded ring of scratch frame buffers that never writes into memory a live
 /// consumer may still be reading. A slot's byte[] is only rewritten after at least
 /// <paramref name="redLine"/> rents have cycled since it was last handed out; a slot
 /// still inside its red line is skipped, and if the whole ring is inside its red line a
 /// fresh buffer is handed out rather than lapping a loaned slot. Length-mismatched
 /// buffers are always replaced by a fresh allocation (the previous array is orphaned,
 /// never overwritten), so a hand-out keeps its bytes for as long as anyone holds it.
 ///
 /// The screen capture's consumer contract makes this structural necessity (slice 16,
 /// 2026-09-14): <c>ScreenCaptureManager</c> keeps each delivered frame as
 /// <c>session.LatestFrame</c> across conversions and the dispatcher preview copy lags,
 /// so a held frame can survive several conversions. The 1742 take recorded one torn
 /// frame (new-top/old-bottom at the webcam split) — a ring slot rewritten under the
 /// consumer's read. Depth 8 × the conversion interval already exceeded the worst
 /// observed hold (~50ms, take-14 rule); the red line makes the guarantee structural
 /// instead of a sizing coincidence.
 /// </summary>
 internal sealed class FrameRingBuffer
 {
    private readonly byte[]?[] _slots;
    private readonly long[] _lastHandout;
    private readonly int _redLine;
    private readonly object _lock = new();
    private int _next;
    private long _seq;
    private long _allocations;
    public FrameRingBuffer(int depth, int redLine)
    {
        _slots = new byte[depth][];
        _lastHandout = new long[depth];
        for (var i = 0; i < depth; i++) _lastHandout[i] = -redLine;
        _redLine = redLine;
    }
    /// <summary>Buffers freshly allocated after the last <see cref="ConsumeAllocations"/>.</summary>
    public long Allocations
    {
        get { lock (_lock) return _allocations; }
    }
    /// <summary>Returns the allocation count since the last call and resets it.</summary>
    public long ConsumeAllocations()
    {
        lock (_lock)
        {
            var count = _allocations;
            _allocations = 0;
            return count;
        }
    }
    /// <summary>Hands out a scratch buffer of <paramref name="size"/> bytes.</summary>
    public byte[] Rent(int size)
    {
        lock (_lock)
        {
            var seq = ++_seq;
            for (var tries = 0; tries < _slots.Length; tries++)
            {
                var idx = (_next + tries) % _slots.Length;
                // Red line: rewriting this slot could hit a frame a consumer still reads.
                if (seq - _lastHandout[idx] < _redLine) continue;
                _next = (idx + 1) % _slots.Length;
                if (_slots[idx] is { Length: var len } buf && len == size)
                {
                    _lastHandout[idx] = seq;
                    return buf;
                }
                // Length mismatch (or never allocated): a fresh array, never an in-place
                // overwrite — the previous loan's bytes stay valid for whoever holds it.
                _allocations++;
                var fresh = new byte[size];
                _slots[idx] = fresh;
                _lastHandout[idx] = seq;
                return fresh;
            }
            // Defensive: the whole ring is inside its red line — do not lap a loaned slot.
            _allocations++;
            return new byte[size];
        }
    }
 }
@@ -0,0 +1,24 @@
 using System.Diagnostics;
 using System.IO;
 namespace ytLive.Services;
 /// <summary>
 /// TASK 21: seam around the media decoder's subprocess (ffmpeg <c>rawvideo</c>).
 /// Exposes the raw binary stdout (frames) and exit control, so
 /// <see cref="MediaVideoSource"/> never touches <c>System.Diagnostics.Process</c>
 /// directly and tests can fake the whole decode. Mirrors the encoder's
 /// <c>IEncoderProcess</c> but with a binary <see cref="StandardOutput"/>.
 /// </summary>
 public interface IDecodeProcess : IDisposable
 {
    void Start(ProcessStartInfo startInfo);
    /// <summary>Raw binary stdout — the <c>rawvideo</c> BGRA frame bytes.</summary>
    Stream StandardOutput { get; }
    bool HasExited { get; }
    int ExitCode { get; }
    void Kill();
    Task WaitForExitAsync(CancellationToken cancellationToken = default);
 }
@@ -0,0 +1,26 @@
 namespace ytLive.Services;
 /// <summary>
 /// TASK 21: a media file decoder exposed to <see cref="MediaVideoSourceManager"/>.
 /// Mirrors <c>IScreenCaptureSource</c>/<c>ICameraFrameSource</c> so the manager
 /// (and tests) treat a local video file like any other frame source: start/stop
 /// and a per-frame <see cref="FrameAvailable"/> event consumers coalesce.
 /// </summary>
 public interface IMediaFrameSource : IDisposable
 {
    string Key { get; }
    /// <summary>When true, the decoder restarts from the beginning on natural EOF
    /// instead of raising <see cref="Completed"/> (used for BRB/starting-soon loops).</summary>
    bool Looping { get; set; }
    /// <summary>Raised (on a worker thread) for each decoded frame.</summary>
    event Action<VideoFrame>? FrameAvailable;
    /// <summary>Raised when the file finishes decoding (natural EOF) — not raised
    /// while <see cref="Looping"/> is true.</summary>
    event Action? Completed;
    Task StartAsync(CancellationToken cancellationToken = default);
    Task StopAsync();
 }
@@ -0,0 +1,15 @@
 using System.Collections.Generic;
 using ytLive.Models;
 namespace ytLive.Services;
 /// <summary>Session-scoped seam that lists open top-level windows for the
 /// "Capture Window…" submenu. Mirrors <see cref="IFullScreenDetector"/> so the
 /// VM never depends on a specific Win32 implementation (and tests hand in a
 /// fake enumerator).</summary>
 public interface IWindowEnumerator
 {
    /// <summary>Visible, user-facing top-level windows belonging to other
    /// processes, ordered for display (title, process name).</summary>
    IReadOnlyList<WindowInfo> Enumerate();
 }
@@ -0,0 +1,41 @@
 using System.Security.Cryptography;
 using Microsoft.Data.Sqlite;
 namespace ytLive.Services;
 public partial class LayoutStore : IDisposable
 {
    public byte[]? GetAssetBytes(string assetId)
    {
        using var cmd = _connection.CreateCommand();
        cmd.CommandText = "SELECT Data FROM Asset WHERE Id = $id";
        cmd.Parameters.AddWithValue("$id", assetId);
        return cmd.ExecuteScalar() as byte[];
    }
    public string UpsertAsset(byte[] data, int pixelWidth, int pixelHeight)
    {
        var hash = Convert.ToHexString(SHA256.HashData(data));
        var id = Guid.NewGuid().ToString();
        using var cmd = _connection.CreateCommand();
        cmd.CommandText = """
            INSERT INTO Asset (Id, Hash, Data, PixelWidth, PixelHeight)
            VALUES ($id, $hash, $data, $w, $h)
            ON CONFLICT(Hash) DO NOTHING;
            """;
        cmd.Parameters.AddWithValue("$id", id);
        cmd.Parameters.AddWithValue("$hash", hash);
        cmd.Parameters.AddWithValue("$data", data);
        cmd.Parameters.AddWithValue("$w", pixelWidth);
        cmd.Parameters.AddWithValue("$h", pixelHeight);
        cmd.ExecuteNonQuery();
        cmd.CommandText = "SELECT Id FROM Asset WHERE Hash = $hash;";
        return (string)cmd.ExecuteScalar()!;
    }
    // ─── License (TASK 10 — Polar billing) ───
    /// <summary>The saved license key, or null if never entered.</summary>
 }
@@ -0,0 +1,240 @@
 using Microsoft.Data.Sqlite;
 using ytLive.Models;
 namespace ytLive.Services;
 public partial class LayoutStore : IDisposable
 {
    public List<Scene> Load()
    {
        Webcam = null;
        Socials = null;
        Music = null;
        var scenes = new List<Scene>();
        var sourcesByScene = new Dictionary<string, List<(Source Source, int Sort)>>();
        var configsByScene = new Dictionary<string, List<(WebcamSceneConfig Config, int Sort)>>();
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = "SELECT Id, Name, IsHidden, IsChatScene, HasBackground, HasSocialBar FROM Scene ORDER BY SortOrder";
            using var reader = cmd.ExecuteReader();
            while (reader.Read())
            {
                scenes.Add(new Scene
                {
                    Id = reader.GetString(0),
                    Name = reader.GetString(1),
                    IsHidden = reader.GetInt32(2) != 0,
                    IsChatScene = reader.GetInt32(3) != 0,
                    HasBackground = reader.GetInt32(4) != 0,
                    HasSocialBar = reader.FieldCount > 5 && !reader.IsDBNull(5) && reader.GetInt32(5) != 0,
                });
            }
        }
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = "SELECT Id, DeviceId, Name FROM Webcam;";
            using var reader = cmd.ExecuteReader();
            if (reader.Read())
            {
                Webcam = new Webcam
                {
                    Id = reader.GetString(0),
                    DeviceId = reader.GetString(1),
                    Name = reader.GetString(2),
                };
            }
        }
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = "SELECT Id, BarPosition, BarEnabled FROM Socials LIMIT 1;";
            using var reader = cmd.ExecuteReader();
            if (reader.Read())
            {
                Socials = new SocialsConfig
                {
                    BarPosition = Enum.TryParse<SocialBarPosition>(reader.GetString(1), out var pos) ? pos : SocialBarPosition.Bottom,
                    BarEnabled = reader.FieldCount > 2 && !reader.IsDBNull(2) && reader.GetInt32(2) != 0,
                };
                var socialsId = reader.GetString(0);
                using var entryCmd = _connection.CreateCommand();
                entryCmd.CommandText = "SELECT Service, Handle, ProfileUrl, Software FROM SocialEntry WHERE SocialsId = $id ORDER BY SortOrder;";
                entryCmd.Parameters.AddWithValue("$id", socialsId);
                using var entryReader = entryCmd.ExecuteReader();
                while (entryReader.Read())
                {
                    Socials.Entries.Add(new SocialEntry
                    {
                        Service = Enum.TryParse<SocialService>(entryReader.GetString(0), out var svc) ? svc : SocialService.Link,
                        Handle = entryReader.GetString(1),
                        ProfileUrl = entryReader.GetString(2),
                        FediverseSoftware = entryReader.FieldCount > 3 && !entryReader.IsDBNull(3) ? entryReader.GetString(3) : null,
                    });
                }
            }
        }
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = "SELECT TrackPath, IsEnabled FROM Music LIMIT 1;";
            using var reader = cmd.ExecuteReader();
            if (reader.Read())
            {
                Music = new Music
                {
                    TrackPath = reader.GetString(0),
                    IsEnabled = reader.GetInt32(1) != 0,
                };
            }
        }
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = """
                SELECT Id, SceneId, AssetId, Type, Name, IsEnabled,
                       X, Y, Width, Height, Opacity, MonitorIndex, ClipShape, IsMirrored,
                       IsBackground, CaptureKey, ShowDesktop,
                       ChatFontSize, ChatFontColor, ChatBackgroundColor, ChatMaxMessages,
                       ChatShowTimestamps, ChatShowBadges, ChatMemberColor, ChatSuperChatColor,
                       WebUri, MediaPath, MediaIsLooping, MediaVolume, MediaPlaybackState,
                       AlertVideoAssetId, AlertVideoPath, AlertUseDefaultVideo, AlertShowTicker, AlertVideoVolume, SortOrder,
                       AlertDisplayMethod
                FROM Source ORDER BY SortOrder
                """;
            using var reader = cmd.ExecuteReader();
            while (reader.Read())
            {
                var sceneId = reader.GetString(1);
                var type = Enum.Parse<SourceType>(reader.GetString(3));
                var source = new Source
                {
                    Id = reader.GetString(0),
                    AssetId = reader.IsDBNull(2) ? null : reader.GetString(2),
                    Type = type,
                    Name = reader.GetString(4),
                    IsEnabled = reader.GetInt32(5) != 0,
                    X = reader.GetDouble(6),
                    Y = reader.GetDouble(7),
                    Width = reader.GetDouble(8),
                    Height = reader.GetDouble(9),
                    Opacity = reader.GetDouble(10),
                    MonitorIndex = reader.IsDBNull(11) ? null : reader.GetInt32(11),
                    ClipShape = Enum.TryParse<ClipShape>(reader.GetString(12), out var clip) ? clip : ClipShape.Traditional,
                    IsMirrored = reader.GetInt32(13) != 0,
                    // Rows saved before the Type setter derived the flag carry
                    // IsBackground=0; derive from Type, keeping the persisted bit
                    // for legacy DisplayCapture backdrops.
                    IsBackground = type == SourceType.Background || reader.GetInt32(14) != 0,
                    CaptureKey = reader.IsDBNull(15) ? null : reader.GetString(15),
                    ShowDesktop = reader.GetInt32(16) != 0,
                    ChatFontSize = reader.IsDBNull(17) ? 16 : reader.GetDouble(17),
                    ChatFontColor = reader.IsDBNull(18) ? "#FFFFFF" : reader.GetString(18),
                    ChatBackgroundColor = reader.IsDBNull(19) ? "#80000000" : reader.GetString(19),
                    ChatMaxMessages = reader.IsDBNull(20) ? 5 : reader.GetInt32(20),
                    ChatShowTimestamps = reader.IsDBNull(21) ? true : reader.GetInt32(21) != 0,
                    ChatShowBadges = reader.IsDBNull(22) ? true : reader.GetInt32(22) != 0,
                    ChatMemberColor = reader.IsDBNull(23) ? "#e94560" : reader.GetString(23),
                    ChatSuperChatColor = reader.IsDBNull(24) ? "#eab308" : reader.GetString(24),
                    WebUri = reader.IsDBNull(25) ? null : reader.GetString(25),
                    MediaPath = reader.IsDBNull(26) ? null : reader.GetString(26),
                    MediaIsLooping = reader.IsDBNull(27) ? false : reader.GetInt32(27) != 0,
                    MediaVolume = reader.IsDBNull(28) ? 1.0 : reader.GetDouble(28),
                    MediaPlaybackState = reader.IsDBNull(29)
                        ? MediaPlaybackState.Stopped
                        : Enum.TryParse<MediaPlaybackState>(reader.GetString(29), out var ps)
                            ? ps
                            : MediaPlaybackState.Stopped,
                    AlertVideoAssetId = reader.IsDBNull(30) ? null : reader.GetString(30),
                    AlertVideoPath = reader.IsDBNull(31) ? null : reader.GetString(31),
                    AlertUseDefaultVideo = reader.IsDBNull(32) ? true : reader.GetInt32(32) != 0,
                    AlertShowTicker = reader.IsDBNull(33) ? true : reader.GetInt32(33) != 0,
                    AlertVideoVolume = reader.IsDBNull(34) ? 1.0 : reader.GetDouble(34),
                    AlertDisplayMethod = reader.IsDBNull(36) ? AlertDisplayMethod.TickerScroll : (AlertDisplayMethod)reader.GetInt32(36),
                };
                if (!sourcesByScene.TryGetValue(sceneId, out var list))
                    sourcesByScene[sceneId] = list = new List<(Source, int)>();
                list.Add((source, reader.GetInt32(35)));
            }
        }
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = """
                SELECT SceneId, WebcamId, IsVisible, X, Y, Width, Height, Opacity,
                       ClipShape, IsMirrored, BorderColor, BorderOpacity, BorderWidth, BorderAnimation,
                       RectWidth, RectHeight, SortOrder
                FROM WebcamSceneConfig ORDER BY SortOrder
                """;
            using var reader = cmd.ExecuteReader();
            while (reader.Read())
            {
                var sceneId = reader.GetString(0);
                var config = new WebcamSceneConfig
                {
                    WebcamId = reader.GetString(1),
                    Name = Webcam?.Name ?? "Webcam",
                    IsVisible = reader.GetInt32(2) != 0,
                    X = reader.GetDouble(3),
                    Y = reader.GetDouble(4),
                    Width = reader.GetDouble(5),
                    Height = reader.GetDouble(6),
                    Opacity = reader.GetDouble(7),
                    ClipShape = Enum.TryParse<ClipShape>(reader.GetString(8), out var clip) ? clip : ClipShape.Traditional,
                    IsMirrored = reader.GetInt32(9) != 0,
                    BorderColor = reader.IsDBNull(10) ? string.Empty : reader.GetString(10),
                    BorderOpacity = reader.IsDBNull(11) ? 1.0 : reader.GetDouble(11),
                    BorderWidth = reader.IsDBNull(12) ? 0 : reader.GetInt32(12),
                    BorderAnimation = Enum.TryParse<BorderAnimation>(reader.GetString(13), out var anim) ? anim : BorderAnimation.None,
                    RectWidth = reader.IsDBNull(14) ? null : reader.GetDouble(14),
                    RectHeight = reader.IsDBNull(15) ? null : reader.GetDouble(15),
                };
                if (!configsByScene.TryGetValue(sceneId, out var list))
                    configsByScene[sceneId] = list = new List<(WebcamSceneConfig, int)>();
                list.Add((config, reader.GetInt32(16)));
            }
        }
        foreach (var scene in scenes)
        {
            // Source and WebcamSceneConfig rows share ONE z-order space per scene
            // (both SortOrders = the element's index within scene.Elements). Merge
            // the two tables' rows by that shared z rather than appending all
            // sources before all configs — a webcam slotted between sources must
            // reload in place. Legacy rows (written before the unified space) may
            // tie at 0: break ties sources-first, so old data reads back stacked
            // the same way it did pre-unification.
            var ordered = new List<(int Sort, SceneElement Element)>();
            if (sourcesByScene.TryGetValue(scene.Id, out var sources))
                foreach (var (source, sort) in sources)
                    ordered.Add((sort, source));
            if (configsByScene.TryGetValue(scene.Id, out var configs))
                foreach (var (config, sort) in configs)
                    ordered.Add((sort, config));
            foreach (var (_, element) in ordered.OrderBy(e => e.Sort).ThenBy(e => e.Element is Source ? 0 : 1))
                scene.Elements.Add(element);
            var bg = scene.Elements.OfType<Source>().FirstOrDefault(s => s.IsBackground);
            if (bg != null)
            {
                // Load from source-keyed settings (new) or scene-keyed (legacy migration)
                var path = GetSetting($"BackgroundPath_{bg.Id}");
                if (string.IsNullOrWhiteSpace(path))
                    path = GetSetting($"BackgroundPath_{scene.Id}");
                if (!string.IsNullOrWhiteSpace(path))
                    bg.CustomBackgroundPath = path;
                var useDefault = GetSetting($"BackgroundUseDefault_{bg.Id}");
                if (string.IsNullOrWhiteSpace(useDefault))
                    useDefault = GetSetting($"BackgroundUseDefault_{scene.Id}");
                if (useDefault == "0")
                    bg.UseDefaultBackground = false;
            }
        }
        return scenes;
    }
 }
@@ -0,0 +1,552 @@
 using Microsoft.Data.Sqlite;
 using ytLive.Models;
 namespace ytLive.Services;
 public partial class LayoutStore : IDisposable
 {
    private void EnsureSchema()
    {
        string[] statements =
        {
            """
            CREATE TABLE IF NOT EXISTS Scene (
                Id TEXT PRIMARY KEY,
                Name TEXT NOT NULL,
                IsHidden INTEGER NOT NULL DEFAULT 0,
                IsChatScene INTEGER NOT NULL DEFAULT 0,
                HasBackground INTEGER NOT NULL DEFAULT 1,
                SortOrder INTEGER NOT NULL DEFAULT 0
            );
            """,
            """
            CREATE TABLE IF NOT EXISTS Asset (
                Id TEXT PRIMARY KEY,
                Hash TEXT NOT NULL UNIQUE,
                Data BLOB NOT NULL,
                PixelWidth INTEGER NOT NULL DEFAULT 0,
                PixelHeight INTEGER NOT NULL DEFAULT 0
            );
            """,
            """
            CREATE TABLE IF NOT EXISTS Source (
                Id TEXT PRIMARY KEY,
                SceneId TEXT NOT NULL REFERENCES Scene(Id) ON DELETE CASCADE,
                AssetId TEXT REFERENCES Asset(Id),
                Type TEXT NOT NULL,
                Name TEXT NOT NULL,
                IsEnabled INTEGER NOT NULL DEFAULT 1,
                X REAL NOT NULL DEFAULT 0,
                Y REAL NOT NULL DEFAULT 0,
                Width REAL NOT NULL DEFAULT 0,
                Height REAL NOT NULL DEFAULT 0,
                Opacity REAL NOT NULL DEFAULT 1,
                MonitorIndex INTEGER,
                DeviceId TEXT,
                ClipShape TEXT NOT NULL DEFAULT 'Traditional',
                IsMirrored INTEGER NOT NULL DEFAULT 0,
                IsBackground INTEGER NOT NULL DEFAULT 0,
                CaptureKey TEXT,
                SortOrder INTEGER NOT NULL DEFAULT 0
            );
            """,
            """
            CREATE TABLE IF NOT EXISTS Webcam (
                Id TEXT PRIMARY KEY,
                DeviceId TEXT NOT NULL UNIQUE,
                Name TEXT NOT NULL
            );
            """,
            """
            CREATE TABLE IF NOT EXISTS WebcamSceneConfig (
                SceneId TEXT NOT NULL REFERENCES Scene(Id) ON DELETE CASCADE,
                WebcamId TEXT NOT NULL REFERENCES Webcam(Id) ON DELETE CASCADE,
                IsVisible INTEGER NOT NULL DEFAULT 1,
                X REAL NOT NULL DEFAULT 0,
                Y REAL NOT NULL DEFAULT 0,
                Width REAL NOT NULL DEFAULT 0,
                Height REAL NOT NULL DEFAULT 0,
                Opacity REAL NOT NULL DEFAULT 1,
                ClipShape TEXT NOT NULL DEFAULT 'Traditional',
                IsMirrored INTEGER NOT NULL DEFAULT 0,
                RectWidth REAL,
                RectHeight REAL,
                BorderColor TEXT,
                BorderOpacity REAL NOT NULL DEFAULT 1,
                BorderWidth INTEGER NOT NULL DEFAULT 0,
                BorderAnimation TEXT NOT NULL DEFAULT 'None',
                SortOrder INTEGER NOT NULL DEFAULT 0,
                PRIMARY KEY (SceneId, WebcamId)
            );
            """,
            """
            CREATE TABLE IF NOT EXISTS Socials (
                Id TEXT PRIMARY KEY,
                BarPosition TEXT NOT NULL DEFAULT 'Bottom',
                BarJustify TEXT NOT NULL DEFAULT 'Center'
            );
            """,
            """
            CREATE TABLE IF NOT EXISTS SocialEntry (
                Id TEXT PRIMARY KEY,
                SocialsId TEXT NOT NULL REFERENCES Socials(Id) ON DELETE CASCADE,
                Service TEXT NOT NULL,
                Handle TEXT NOT NULL,
                ProfileUrl TEXT NOT NULL,
                SortOrder INTEGER NOT NULL DEFAULT 0
            );
            """,
            """
            CREATE TABLE IF NOT EXISTS Music (
                Id TEXT PRIMARY KEY,
                TrackPath TEXT NOT NULL,
                IsEnabled INTEGER NOT NULL DEFAULT 0
            );
            """,
            """
            CREATE TABLE IF NOT EXISTS Settings (
                Key TEXT PRIMARY KEY,
                Value TEXT NOT NULL
            );
            """,
            // v9 → v10 (TASK 39): YPP journey-tracker snapshots, appended on every
            // stats refresh. The history is the raw data a later analytics slice
            // reads to compute velocity/(de)acceleration/ETA.
            """
            CREATE TABLE IF NOT EXISTS YppSnapshot (
                CapturedAtUtc TEXT NOT NULL PRIMARY KEY,
                SubscriberCount INTEGER NOT NULL,
                VideoCount INTEGER NOT NULL,
                TotalViews INTEGER NOT NULL,
                UploadsLast90Days INTEGER NOT NULL,
                CommunityGuidelinesGoodStanding INTEGER NOT NULL,
                CopyrightStrikesGoodStanding INTEGER NOT NULL,
                ContentIdClaimsGoodStanding INTEGER NOT NULL,
                OverallGoodStanding INTEGER NOT NULL
            );
            """,
        };
        foreach (var sql in statements)
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = sql;
            cmd.ExecuteNonQuery();
        }
        MigrateSourceTable();
        MigrateWebcamConfigTable();
        MigrateSceneTable();
        MigrateSceneSocialBarColumn();
        MigrateSocialsTable();
        MigrateSocialEntryTable();
        if (GetUserVersion() < 3)
            MigrateToV3();
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = "PRAGMA user_version = 10;";
            cmd.ExecuteNonQuery();
        }
    }
    // v1 → v2: Source gains ClipShape + IsMirrored (webcam clip/mirror prefs).
    // CREATE TABLE IF NOT EXISTS doesn't touch existing tables, so pre-v2 DBs
    // get the columns here instead.
    private void MigrateSourceTable()
    {
        var columns = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = "PRAGMA table_info(Source);";
            using var reader = cmd.ExecuteReader();
            while (reader.Read())
                columns.Add(reader.GetString(1));
        }
        if (!columns.Contains("ClipShape"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN ClipShape TEXT NOT NULL DEFAULT 'Traditional';";
            cmd.ExecuteNonQuery();
        }
        if (!columns.Contains("AlertDisplayMethod"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN AlertDisplayMethod INTEGER NOT NULL DEFAULT 0;";
            cmd.ExecuteNonQuery();
        }
        if (!columns.Contains("IsMirrored"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN IsMirrored INTEGER NOT NULL DEFAULT 0;";
            cmd.ExecuteNonQuery();
        }
        if (columns.Contains("IsBackdrop"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source RENAME COLUMN IsBackdrop TO IsBackground;";
            cmd.ExecuteNonQuery();
        }
        else if (!columns.Contains("IsBackground"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN IsBackground INTEGER NOT NULL DEFAULT 0;";
            cmd.ExecuteNonQuery();
        }
        if (!columns.Contains("CaptureKey"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN CaptureKey TEXT;";
            cmd.ExecuteNonQuery();
        }
        // TASK 3.18: ChatBox overlay source
        if (!columns.Contains("ChatFontSize"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN ChatFontSize REAL NOT NULL DEFAULT 16;";
            cmd.ExecuteNonQuery();
        }
        if (!columns.Contains("ChatFontColor"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN ChatFontColor TEXT NOT NULL DEFAULT '#FFFFFF';";
            cmd.ExecuteNonQuery();
        }
        if (!columns.Contains("ChatBackgroundColor"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN ChatBackgroundColor TEXT NOT NULL DEFAULT '#80000000';";
            cmd.ExecuteNonQuery();
        }
        if (!columns.Contains("ChatMaxMessages"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN ChatMaxMessages INTEGER NOT NULL DEFAULT 5;";
            cmd.ExecuteNonQuery();
        }
        if (!columns.Contains("ChatShowTimestamps"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN ChatShowTimestamps INTEGER NOT NULL DEFAULT 1;";
            cmd.ExecuteNonQuery();
        }
        if (!columns.Contains("ChatShowBadges"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN ChatShowBadges INTEGER NOT NULL DEFAULT 1;";
            cmd.ExecuteNonQuery();
        }
        if (!columns.Contains("ChatMemberColor"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN ChatMemberColor TEXT NOT NULL DEFAULT '#e94560';";
            cmd.ExecuteNonQuery();
        }
        if (!columns.Contains("ChatSuperChatColor"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN ChatSuperChatColor TEXT NOT NULL DEFAULT '#eab308';";
            cmd.ExecuteNonQuery();
        }
        if (!columns.Contains("ShowDesktop"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN ShowDesktop INTEGER NOT NULL DEFAULT 0;";
            cmd.ExecuteNonQuery();
        }
        if (!columns.Contains("WebUri"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN WebUri TEXT;";
            cmd.ExecuteNonQuery();
        }
        // TASK 21: Media source (video/audio file playback)
        if (!columns.Contains("MediaPath"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN MediaPath TEXT;";
            cmd.ExecuteNonQuery();
        }
        if (!columns.Contains("MediaIsLooping"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN MediaIsLooping INTEGER NOT NULL DEFAULT 0;";
            cmd.ExecuteNonQuery();
        }
        if (!columns.Contains("MediaVolume"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN MediaVolume REAL NOT NULL DEFAULT 1;";
            cmd.ExecuteNonQuery();
        }
        if (!columns.Contains("MediaPlaybackState"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN MediaPlaybackState TEXT NOT NULL DEFAULT 'Stopped';";
            cmd.ExecuteNonQuery();
        }
        // TASK 47: alert video config. The default clip asset id + the creator's
        // replacement path (a FILE reference, never a stored BLOB) + the pill,
        // ticker toggle and volume live on the row.
        if (!columns.Contains("AlertVideoAssetId"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN AlertVideoAssetId TEXT;";
            cmd.ExecuteNonQuery();
        }
        if (!columns.Contains("AlertVideoPath"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN AlertVideoPath TEXT;";
            cmd.ExecuteNonQuery();
        }
        if (!columns.Contains("AlertUseDefaultVideo"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN AlertUseDefaultVideo INTEGER NOT NULL DEFAULT 1;";
            cmd.ExecuteNonQuery();
        }
        if (!columns.Contains("AlertShowTicker"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN AlertShowTicker INTEGER NOT NULL DEFAULT 1;";
            cmd.ExecuteNonQuery();
        }
        if (!columns.Contains("AlertVideoVolume"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Source ADD COLUMN AlertVideoVolume REAL NOT NULL DEFAULT 1;";
            cmd.ExecuteNonQuery();
        }
        // Rename legacy "Backdrop" display name to "Background" in existing rows
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = "UPDATE Source SET Name = 'Background' WHERE Name = 'Backdrop';";
            cmd.ExecuteNonQuery();
        }
    }
    // v3 → v4: WebcamSceneConfig gains RectWidth/RectHeight (the pre-Round rect,
    // so a reloaded Round webcam restores its aspect on toggle-back).
    private void MigrateWebcamConfigTable()
    {
        var columns = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = "PRAGMA table_info(WebcamSceneConfig);";
            using var reader = cmd.ExecuteReader();
            while (reader.Read())
                columns.Add(reader.GetString(1));
        }
        if (!columns.Contains("RectWidth"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE WebcamSceneConfig ADD COLUMN RectWidth REAL;";
            cmd.ExecuteNonQuery();
        }
        if (!columns.Contains("RectHeight"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE WebcamSceneConfig ADD COLUMN RectHeight REAL;";
            cmd.ExecuteNonQuery();
        }
    }
    // v2 → v3: the webcam leaves the Source table. Any webcam Source rows become
    // one Webcam identity (first row — one camera app-wide) + a WebcamSceneConfig
    // per scene that had one, then the webcam rows are deleted. No backfill:
    // scenes without the webcam stay webcam-free.
    private void MigrateToV3()
    {
        var rows = new List<(string Id, string SceneId, string Name, double X, double Y, double W, double H, double Opacity, string DeviceId, string ClipShape, bool IsMirrored)>();
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = """
                SELECT Id, SceneId, Name, X, Y, Width, Height, Opacity, DeviceId, ClipShape, IsMirrored
                FROM Source WHERE Type = 'Webcam' ORDER BY SortOrder;
                """;
            using var reader = cmd.ExecuteReader();
            while (reader.Read())
            {
                rows.Add((
                    reader.GetString(0),
                    reader.GetString(1),
                    reader.GetString(2),
                    reader.GetDouble(3),
                    reader.GetDouble(4),
                    reader.GetDouble(5),
                    reader.GetDouble(6),
                    reader.GetDouble(7),
                    reader.IsDBNull(8) ? string.Empty : reader.GetString(8),
                    reader.GetString(9),
                    reader.GetInt32(10) != 0));
            }
        }
        if (rows.Count == 0) return;
        using var tx = _connection.BeginTransaction();
        var webcamId = Guid.NewGuid().ToString();
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = "INSERT INTO Webcam (Id, DeviceId, Name) VALUES ($id, $device, $name);";
            cmd.Transaction = tx;
            cmd.Parameters.AddWithValue("$id", webcamId);
            cmd.Parameters.AddWithValue("$device", rows[0].DeviceId);
            cmd.Parameters.AddWithValue("$name", rows[0].Name);
            cmd.ExecuteNonQuery();
        }
        foreach (var row in rows)
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = """
                INSERT INTO WebcamSceneConfig
                    (SceneId, WebcamId, IsVisible, X, Y, Width, Height, Opacity,
                     ClipShape, IsMirrored, BorderColor, BorderOpacity, BorderWidth, BorderAnimation, SortOrder)
                VALUES ($sceneId, $webcamId, 1, $x, $y, $w, $h, $opacity,
                        $clip, $mirrored, NULL, 1, 0, 'None', 0);
                """;
            cmd.Transaction = tx;
            cmd.Parameters.AddWithValue("$sceneId", row.SceneId);
            cmd.Parameters.AddWithValue("$webcamId", webcamId);
            cmd.Parameters.AddWithValue("$x", row.X);
            cmd.Parameters.AddWithValue("$y", row.Y);
            cmd.Parameters.AddWithValue("$w", row.W);
            cmd.Parameters.AddWithValue("$h", row.H);
            cmd.Parameters.AddWithValue("$opacity", row.Opacity);
            cmd.Parameters.AddWithValue("$clip", row.ClipShape);
            cmd.Parameters.AddWithValue("$mirrored", row.IsMirrored ? 1 : 0);
            cmd.ExecuteNonQuery();
        }
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = "DELETE FROM Source WHERE Type = 'Webcam';";
            cmd.Transaction = tx;
            cmd.ExecuteNonQuery();
        }
        tx.Commit();
    }
    // v5 → v6: Scene gains HasBackground. Added columns default to true; the
    // ONE-TIME backfill (runs only when the column is first added) turns every
    // non-Live canonical scene off and drops their background sources — the fix for
    // DBs saved before the Live-only policy. MainViewModel.NormalizeBackgrounds
    // re-runs the same normalization on every load for DBs that miss the backfill.
    private void MigrateSceneTable()
    {
        var columns = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = "PRAGMA table_info(Scene);";
            using var reader = cmd.ExecuteReader();
            while (reader.Read())
                columns.Add(reader.GetString(1));
        }
        if (columns.Contains("HasBackdrop"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Scene RENAME COLUMN HasBackdrop TO HasBackground;";
            cmd.ExecuteNonQuery();
        }
        else if (columns.Contains("HasBackground"))
        {
            return;
        }
        if (!columns.Contains("HasBackground"))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "ALTER TABLE Scene ADD COLUMN HasBackground INTEGER NOT NULL DEFAULT 1;";
            cmd.ExecuteNonQuery();
        }
        const string noBackground = "('starting', 'brb', 'chat', 'ending')";
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = $"UPDATE Scene SET HasBackground = 0 WHERE LOWER(TRIM(Name)) IN {noBackground};";
            cmd.ExecuteNonQuery();
        }
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = $"""
                DELETE FROM Source
                WHERE IsBackground = 1 AND SceneId IN
                    (SELECT Id FROM Scene WHERE LOWER(TRIM(Name)) IN {noBackground});
                """;
            cmd.ExecuteNonQuery();
        }
    }
    // v6 → v7: Scene gains HasSocialBar (the per-scene social-bar toggle).
    // Defaults to 0 (off) — the creator adds it explicitly via the footer [+].
    private void MigrateSceneSocialBarColumn()
    {
        var columns = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = "PRAGMA table_info(Scene);";
            using var reader = cmd.ExecuteReader();
            while (reader.Read())
                columns.Add(reader.GetString(1));
        }
        if (columns.Contains("HasSocialBar")) return;
        using var alter = _connection.CreateCommand();
        alter.CommandText = "ALTER TABLE Scene ADD COLUMN HasSocialBar INTEGER NOT NULL DEFAULT 0;";
        alter.ExecuteNonQuery();
    }
    // v7 → v8: Socials gains BarEnabled (the dialog's show/hide switch). The old
    // BarJustify column stays for back-compat but is no longer read or written.
    private void MigrateSocialsTable()
    {
        var columns = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = "PRAGMA table_info(Socials);";
            using var reader = cmd.ExecuteReader();
            while (reader.Read())
                columns.Add(reader.GetString(1));
        }
        if (columns.Contains("BarEnabled")) return;
        using var alter = _connection.CreateCommand();
        alter.CommandText = "ALTER TABLE Socials ADD COLUMN BarEnabled INTEGER NOT NULL DEFAULT 1;";
        alter.ExecuteNonQuery();
    }
    // v8 → v9: SocialEntry gains Software (the fediverse instance's nodeinfo
    // software name) so a reloaded entry still shows the right service logo.
    private void MigrateSocialEntryTable()
    {
        var columns = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = "PRAGMA table_info(SocialEntry);";
            using var reader = cmd.ExecuteReader();
            while (reader.Read())
                columns.Add(reader.GetString(1));
        }
        if (columns.Contains("Software")) return;
        using var alter = _connection.CreateCommand();
        alter.CommandText = "ALTER TABLE SocialEntry ADD COLUMN Software TEXT;";
        alter.ExecuteNonQuery();
    }
 }
@@ -0,0 +1,368 @@
 using Microsoft.Data.Sqlite;
 using ytLive.Models;
 namespace ytLive.Services;
 public partial class LayoutStore : IDisposable
 {
    public void Save(IEnumerable<Scene> scenes, Webcam? webcam, SocialsConfig? socials, Music? music = null)
    {
        using var tx = _connection.BeginTransaction();
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = "DELETE FROM WebcamSceneConfig;";
            cmd.Transaction = tx;
            cmd.ExecuteNonQuery();
        }
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = "DELETE FROM Source;";
            cmd.Transaction = tx;
            cmd.ExecuteNonQuery();
        }
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = "DELETE FROM Webcam;";
            cmd.Transaction = tx;
            cmd.ExecuteNonQuery();
        }
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = "DELETE FROM SocialEntry;";
            cmd.Transaction = tx;
            cmd.ExecuteNonQuery();
        }
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = "DELETE FROM Socials;";
            cmd.Transaction = tx;
            cmd.ExecuteNonQuery();
        }
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = "DELETE FROM Music;";
            cmd.Transaction = tx;
            cmd.ExecuteNonQuery();
        }
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = "DELETE FROM Scene;";
            cmd.Transaction = tx;
            cmd.ExecuteNonQuery();
        }
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = """
                INSERT INTO Scene (Id, Name, IsHidden, IsChatScene, HasBackground, HasSocialBar, SortOrder)
                VALUES ($id, $name, $isHidden, $isChat, $hasBackground, $hasSocialBar, $sort)
                """;
            cmd.Transaction = tx;
            var idP = cmd.Parameters.Add("$id", SqliteType.Text);
            var nameP = cmd.Parameters.Add("$name", SqliteType.Text);
            var hiddenP = cmd.Parameters.Add("$isHidden", SqliteType.Integer);
            var chatP = cmd.Parameters.Add("$isChat", SqliteType.Integer);
            var backgroundP = cmd.Parameters.Add("$hasBackground", SqliteType.Integer);
            var socialBarP = cmd.Parameters.Add("$hasSocialBar", SqliteType.Integer);
            var sortP = cmd.Parameters.Add("$sort", SqliteType.Integer);
            var sort = 0;
            foreach (var scene in scenes)
            {
                idP.Value = scene.Id;
                nameP.Value = scene.Name;
                hiddenP.Value = scene.IsHidden ? 1 : 0;
                chatP.Value = scene.IsChatScene ? 1 : 0;
                backgroundP.Value = scene.HasBackground ? 1 : 0;
                socialBarP.Value = scene.HasSocialBar ? 1 : 0;
                sortP.Value = sort++;
                cmd.ExecuteNonQuery();
            }
        }
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = """
                INSERT INTO Source (Id, SceneId, AssetId, Type, Name, IsEnabled,
                                    X, Y, Width, Height, Opacity, MonitorIndex,
                                    ClipShape, IsMirrored, IsBackground, CaptureKey, ShowDesktop, SortOrder,
                                    ChatFontSize, ChatFontColor, ChatBackgroundColor, ChatMaxMessages,
                                    ChatShowTimestamps, ChatShowBadges, ChatMemberColor, ChatSuperChatColor,
                                    WebUri, MediaPath, MediaIsLooping, MediaVolume, MediaPlaybackState,
                                    AlertVideoAssetId, AlertVideoPath, AlertUseDefaultVideo, AlertShowTicker, AlertVideoVolume,
                                    AlertDisplayMethod)
                VALUES ($id, $sceneId, $assetId, $type, $name, $isEnabled,
                        $x, $y, $w, $h, $opacity, $monitor,
                        $clip, $mirrored, $isBackground, $captureKey, $showDesktop, $sort,
                        $chatFontSize, $chatFontColor, $chatBgColor, $chatMaxMsgs,
                        $chatTimestamps, $chatBadges, $chatMemberColor, $chatSuperChatColor,
                        $webUri, $mediaPath, $mediaIsLooping, $mediaVolume, $mediaPlaybackState,
                        $alertVideoAssetId, $alertVideoPath, $alertUseDefaultVideo, $alertShowTicker, $alertVideoVolume,
                        $alertDisplayMethod)
                """;
            cmd.Transaction = tx;
            var idP = cmd.Parameters.Add("$id", SqliteType.Text);
            var sceneIdP = cmd.Parameters.Add("$sceneId", SqliteType.Text);
            var assetIdP = cmd.Parameters.Add("$assetId", SqliteType.Text);
            var typeP = cmd.Parameters.Add("$type", SqliteType.Text);
            var nameP = cmd.Parameters.Add("$name", SqliteType.Text);
            var enabledP = cmd.Parameters.Add("$isEnabled", SqliteType.Integer);
            var xP = cmd.Parameters.Add("$x", SqliteType.Real);
            var yP = cmd.Parameters.Add("$y", SqliteType.Real);
            var wP = cmd.Parameters.Add("$w", SqliteType.Real);
            var hP = cmd.Parameters.Add("$h", SqliteType.Real);
            var opacityP = cmd.Parameters.Add("$opacity", SqliteType.Real);
            var monitorP = cmd.Parameters.Add("$monitor", SqliteType.Integer);
            var clipP = cmd.Parameters.Add("$clip", SqliteType.Text);
            var mirroredP = cmd.Parameters.Add("$mirrored", SqliteType.Integer);
            var isBackgroundP = cmd.Parameters.Add("$isBackground", SqliteType.Integer);
            var captureKeyP = cmd.Parameters.Add("$captureKey", SqliteType.Text);
            var showDesktopP = cmd.Parameters.Add("$showDesktop", SqliteType.Integer);
            var sortP = cmd.Parameters.Add("$sort", SqliteType.Integer);
            var chatFontSizeP = cmd.Parameters.Add("$chatFontSize", SqliteType.Real);
            var chatFontColorP = cmd.Parameters.Add("$chatFontColor", SqliteType.Text);
            var chatBgColorP = cmd.Parameters.Add("$chatBgColor", SqliteType.Text);
            var chatMaxMsgsP = cmd.Parameters.Add("$chatMaxMsgs", SqliteType.Integer);
            var chatTimestampsP = cmd.Parameters.Add("$chatTimestamps", SqliteType.Integer);
            var chatBadgesP = cmd.Parameters.Add("$chatBadges", SqliteType.Integer);
            var chatMemberColorP = cmd.Parameters.Add("$chatMemberColor", SqliteType.Text);
            var chatSuperChatColorP = cmd.Parameters.Add("$chatSuperChatColor", SqliteType.Text);
            var webUriP = cmd.Parameters.Add("$webUri", SqliteType.Text);
            var mediaPathP = cmd.Parameters.Add("$mediaPath", SqliteType.Text);
            var mediaIsLoopingP = cmd.Parameters.Add("$mediaIsLooping", SqliteType.Integer);
            var mediaVolumeP = cmd.Parameters.Add("$mediaVolume", SqliteType.Real);
            var mediaPlaybackStateP = cmd.Parameters.Add("$mediaPlaybackState", SqliteType.Text);
            var alertVideoAssetIdP = cmd.Parameters.Add("$alertVideoAssetId", SqliteType.Text);
            var alertVideoPathP = cmd.Parameters.Add("$alertVideoPath", SqliteType.Text);
            var alertUseDefaultVideoP = cmd.Parameters.Add("$alertUseDefaultVideo", SqliteType.Integer);
            var alertShowTickerP = cmd.Parameters.Add("$alertShowTicker", SqliteType.Integer);
            var alertVideoVolumeP = cmd.Parameters.Add("$alertVideoVolume", SqliteType.Real);
            var alertDisplayMethodP = cmd.Parameters.Add("$alertDisplayMethod", SqliteType.Integer);
            // Source and WebcamSceneConfig share ONE z-order space per scene:
            // each element gets its index within scene.Elements regardless of
            // table, so a webcam slotted between sources survives save→load.
            // (Pre-unified rows tie at 0 — load breaks ties sources-first.)
            foreach (var scene in scenes)
            {
                var z = 0;
                foreach (var element in scene.Elements)
                {
                    if (element is not Source source) { z++; continue; }
                    idP.Value = source.Id;
                    sceneIdP.Value = scene.Id;
                    assetIdP.Value = (object?)source.AssetId ?? DBNull.Value;
                    typeP.Value = source.Type.ToString();
                    nameP.Value = source.Name;
                    enabledP.Value = source.IsEnabled ? 1 : 0;
                    xP.Value = source.X;
                    yP.Value = source.Y;
                    wP.Value = source.Width;
                    hP.Value = source.Height;
                    opacityP.Value = source.Opacity;
                    monitorP.Value = (object?)source.MonitorIndex ?? DBNull.Value;
                    clipP.Value = source.ClipShape.ToString();
                    mirroredP.Value = source.IsMirrored ? 1 : 0;
                    isBackgroundP.Value = source.IsBackground ? 1 : 0;
                    captureKeyP.Value = (object?)source.CaptureKey ?? DBNull.Value;
                    showDesktopP.Value = source.ShowDesktop ? 1 : 0;
                    sortP.Value = z++;
                    chatFontSizeP.Value = source.ChatFontSize;
                    chatFontColorP.Value = source.ChatFontColor;
                    chatBgColorP.Value = source.ChatBackgroundColor;
                    chatMaxMsgsP.Value = source.ChatMaxMessages;
                    chatTimestampsP.Value = source.ChatShowTimestamps ? 1 : 0;
                    chatBadgesP.Value = source.ChatShowBadges ? 1 : 0;
                    chatMemberColorP.Value = source.ChatMemberColor;
                    chatSuperChatColorP.Value = source.ChatSuperChatColor;
                    webUriP.Value = (object?)source.WebUri ?? DBNull.Value;
                    mediaPathP.Value = (object?)source.MediaPath ?? DBNull.Value;
                    mediaIsLoopingP.Value = source.MediaIsLooping ? 1 : 0;
                    mediaVolumeP.Value = source.MediaVolume;
                    mediaPlaybackStateP.Value = source.MediaPlaybackState.ToString();
                    alertVideoAssetIdP.Value = (object?)source.AlertVideoAssetId ?? DBNull.Value;
                    alertVideoPathP.Value = (object?)source.AlertVideoPath ?? DBNull.Value;
                    alertUseDefaultVideoP.Value = source.AlertUseDefaultVideo ? 1 : 0;
                    alertShowTickerP.Value = source.AlertShowTicker ? 1 : 0;
                    alertVideoVolumeP.Value = source.AlertVideoVolume;
                    alertDisplayMethodP.Value = (int)source.AlertDisplayMethod;
                    cmd.ExecuteNonQuery();
                }
            }
        }
        if (webcam != null)
        {
            using (var cmd = _connection.CreateCommand())
            {
                cmd.CommandText = "INSERT INTO Webcam (Id, DeviceId, Name) VALUES ($id, $device, $name);";
                cmd.Transaction = tx;
                cmd.Parameters.AddWithValue("$id", webcam.Id);
                cmd.Parameters.AddWithValue("$device", webcam.DeviceId);
                cmd.Parameters.AddWithValue("$name", webcam.Name);
                cmd.ExecuteNonQuery();
            }
            using (var cmd = _connection.CreateCommand())
            {
                cmd.CommandText = """
                    INSERT INTO WebcamSceneConfig
                        (SceneId, WebcamId, IsVisible, X, Y, Width, Height, Opacity,
                         ClipShape, IsMirrored, BorderColor, BorderOpacity, BorderWidth, BorderAnimation,
                         RectWidth, RectHeight, SortOrder)
                    VALUES ($sceneId, $webcamId, $isVisible, $x, $y, $w, $h, $opacity,
                            $clip, $mirrored, $borderColor, $borderOpacity, $borderWidth, $borderAnimation,
                            $rectWidth, $rectHeight, $sort)
                    """;
                cmd.Transaction = tx;
                var sceneIdP = cmd.Parameters.Add("$sceneId", SqliteType.Text);
                var webcamIdP = cmd.Parameters.Add("$webcamId", SqliteType.Text);
                var visibleP = cmd.Parameters.Add("$isVisible", SqliteType.Integer);
                var xP = cmd.Parameters.Add("$x", SqliteType.Real);
                var yP = cmd.Parameters.Add("$y", SqliteType.Real);
                var wP = cmd.Parameters.Add("$w", SqliteType.Real);
                var hP = cmd.Parameters.Add("$h", SqliteType.Real);
                var opacityP = cmd.Parameters.Add("$opacity", SqliteType.Real);
                var clipP = cmd.Parameters.Add("$clip", SqliteType.Text);
                var mirroredP = cmd.Parameters.Add("$mirrored", SqliteType.Integer);
                var colorP = cmd.Parameters.Add("$borderColor", SqliteType.Text);
                var borderOpacityP = cmd.Parameters.Add("$borderOpacity", SqliteType.Real);
                var borderWidthP = cmd.Parameters.Add("$borderWidth", SqliteType.Integer);
                var animationP = cmd.Parameters.Add("$borderAnimation", SqliteType.Text);
                var rectWidthP = cmd.Parameters.Add("$rectWidth", SqliteType.Real);
                var rectHeightP = cmd.Parameters.Add("$rectHeight", SqliteType.Real);
                var sortP = cmd.Parameters.Add("$sort", SqliteType.Integer);
                foreach (var scene in scenes)
                {
                    var z = 0;
                    foreach (var element in scene.Elements)
                    {
                        if (element is not WebcamSceneConfig config) { z++; continue; }
                        sceneIdP.Value = scene.Id;
                        webcamIdP.Value = config.WebcamId;
                        visibleP.Value = config.IsVisible ? 1 : 0;
                        xP.Value = config.X;
                        yP.Value = config.Y;
                        wP.Value = config.Width;
                        hP.Value = config.Height;
                        opacityP.Value = config.Opacity;
                        clipP.Value = config.ClipShape.ToString();
                        mirroredP.Value = config.IsMirrored ? 1 : 0;
                        colorP.Value = (object?)(string.IsNullOrEmpty(config.BorderColor) ? null : config.BorderColor) ?? DBNull.Value;
                        borderOpacityP.Value = config.BorderOpacity;
                        borderWidthP.Value = config.BorderWidth;
                        animationP.Value = config.BorderAnimation.ToString();
                        rectWidthP.Value = (object?)config.RectWidth ?? DBNull.Value;
                        rectHeightP.Value = (object?)config.RectHeight ?? DBNull.Value;
                        sortP.Value = z++;
                        cmd.ExecuteNonQuery();
                    }
                }
            }
        }
        if (socials != null && socials.Entries.Count > 0)
        {
            var socialsId = Guid.NewGuid().ToString();
            using (var cmd = _connection.CreateCommand())
            {
                cmd.CommandText = "INSERT INTO Socials (Id, BarPosition, BarEnabled) VALUES ($id, $pos, $enabled);";
                cmd.Transaction = tx;
                cmd.Parameters.AddWithValue("$id", socialsId);
                cmd.Parameters.AddWithValue("$pos", socials.BarPosition.ToString());
                cmd.Parameters.AddWithValue("$enabled", socials.BarEnabled ? 1 : 0);
                cmd.ExecuteNonQuery();
            }
            using var entryCmd = _connection.CreateCommand();
            entryCmd.CommandText = """
                INSERT INTO SocialEntry (Id, SocialsId, Service, Handle, ProfileUrl, Software, SortOrder)
                VALUES ($id, $socialsId, $service, $handle, $url, $software, $sort)
                """;
            entryCmd.Transaction = tx;
            var eId = entryCmd.Parameters.Add("$id", SqliteType.Text);
            var eSocialsId = entryCmd.Parameters.Add("$socialsId", SqliteType.Text);
            var eService = entryCmd.Parameters.Add("$service", SqliteType.Text);
            var eHandle = entryCmd.Parameters.Add("$handle", SqliteType.Text);
            var eUrl = entryCmd.Parameters.Add("$url", SqliteType.Text);
            var eSoftware = entryCmd.Parameters.Add("$software", SqliteType.Text);
            var eSort = entryCmd.Parameters.Add("$sort", SqliteType.Integer);
            var entrySort = 0;
            foreach (var entry in socials.Entries)
            {
                eId.Value = Guid.NewGuid().ToString();
                eSocialsId.Value = socialsId;
                eService.Value = entry.Service.ToString();
                eHandle.Value = entry.Handle;
                eUrl.Value = entry.ProfileUrl;
                eSoftware.Value = (object?)entry.FediverseSoftware ?? DBNull.Value;
                eSort.Value = entrySort++;
                entryCmd.ExecuteNonQuery();
            }
        }
        if (music != null && !string.IsNullOrWhiteSpace(music.TrackPath))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "INSERT INTO Music (Id, TrackPath, IsEnabled) VALUES ($id, $path, $enabled);";
            cmd.Transaction = tx;
            cmd.Parameters.AddWithValue("$id", Guid.NewGuid().ToString());
            cmd.Parameters.AddWithValue("$path", music.TrackPath);
            cmd.Parameters.AddWithValue("$enabled", music.IsEnabled ? 1 : 0);
            cmd.ExecuteNonQuery();
        }
        using (var cmd = _connection.CreateCommand())
        {
            cmd.CommandText = """
                DELETE FROM Asset WHERE Id NOT IN (
                    SELECT AssetId FROM Source WHERE AssetId IS NOT NULL
                    UNION
                    SELECT AlertVideoAssetId FROM Source WHERE AlertVideoAssetId IS NOT NULL
                    UNION
                    SELECT Value FROM Settings WHERE Key = 'AlertDefaultVideoAssetId'
                );
                """;
            cmd.Transaction = tx;
            cmd.ExecuteNonQuery();
        }
        // Save custom background paths and use-default flags per background source
        foreach (var scene in scenes)
        {
            var bg = scene.Elements.OfType<Source>().FirstOrDefault(s => s.IsBackground);
            if (bg == null) continue;
            var pathKey = $"BackgroundPath_{bg.Id}";
            if (!string.IsNullOrWhiteSpace(bg.CustomBackgroundPath))
                UpsertSetting(pathKey, bg.CustomBackgroundPath);
            else
            {
                using var del = _connection.CreateCommand();
                del.CommandText = "DELETE FROM Settings WHERE Key = $key;";
                del.Parameters.AddWithValue("$key", pathKey);
                del.ExecuteNonQuery();
            }
            var defaultKey = $"BackgroundUseDefault_{bg.Id}";
            UpsertSetting(defaultKey, bg.UseDefaultBackground ? "1" : "0");
        }
        // Purge background settings left behind by deleted/duplicated rows
        // (TASK 25 heal drops extras; their keys must not accumulate).
        using (var purge = _connection.CreateCommand())
        {
            purge.Transaction = tx;
            purge.CommandText =
                @"DELETE FROM Settings
                  WHERE (Key LIKE 'BackgroundUseDefault\_%' ESCAPE '\'
                      OR Key LIKE 'BackgroundPath\_%' ESCAPE '\')
                  AND SUBSTR(Key, INSTR(Key, '_') + 1) NOT IN (SELECT Id FROM Source);";
            purge.ExecuteNonQuery();
        }
        tx.Commit();
    }
 }
@@ -0,0 +1,329 @@
 using Microsoft.Data.Sqlite;
 using ytLive.Models;
 namespace ytLive.Services;
 public partial class LayoutStore : IDisposable
 {
    /// <summary>The last picked mic source name, or null if never chosen. Restored
    /// at startup so the sound bar reconnects to the same, already-vetted device.</summary>
    public string? LoadMicSourceName()
    {
        using var cmd = _connection.CreateCommand();
        cmd.CommandText = "SELECT Value FROM Settings WHERE Key = 'MicSourceName';";
        var value = cmd.ExecuteScalar() as string;
        return string.IsNullOrWhiteSpace(value) ? null : value;
    }
    public void SaveMicSourceName(string? name)
    {
        using var cmd = _connection.CreateCommand();
        cmd.CommandText = "DELETE FROM Settings WHERE Key = 'MicSourceName';";
        cmd.ExecuteNonQuery();
        if (string.IsNullOrWhiteSpace(name))
            return;
        using var insert = _connection.CreateCommand();
        insert.CommandText = "INSERT INTO Settings (Key, Value) VALUES ('MicSourceName', $name);";
        insert.Parameters.AddWithValue("$name", name);
        insert.ExecuteNonQuery();
    }
    /// <summary>The global audio-sync offset in milliseconds (TASK 22), −500..500,
    /// default 0: positive delays the mix (audio ahead of video), negative
    /// advances it (audio behind video). Restored at startup so the mixer starts
    /// on the user's offset.</summary>
    public int LoadAudioSyncOffsetMs()
    {
        var value = GetSetting("Audio.SyncOffsetMs");
        return int.TryParse(value, out var ms) ? Math.Clamp(ms, -500, 500) : 0;
    }
    public void SaveAudioSyncOffsetMs(int ms)
    {
        UpsertSetting("Audio.SyncOffsetMs", Math.Clamp(ms, -500, 500).ToString());
    }
    /// <summary>The user's chosen record output folder (TASK 18), or null to use the
    /// default <c>%APPDATA%\ytLlive\recordings</c>. Restored at startup.</summary>
    public string? LoadRecordFolder()
    {
        using var cmd = _connection.CreateCommand();
        cmd.CommandText = "SELECT Value FROM Settings WHERE Key = 'RecordFolder';";
        var value = cmd.ExecuteScalar() as string;
        return string.IsNullOrWhiteSpace(value) ? null : value;
    }
    public void SaveRecordFolder(string? folder)
    {
        using var cmd = _connection.CreateCommand();
        cmd.CommandText = "DELETE FROM Settings WHERE Key = 'RecordFolder';";
        cmd.ExecuteNonQuery();
        if (string.IsNullOrWhiteSpace(folder))
            return;
        using var insert = _connection.CreateCommand();
        insert.CommandText = "INSERT INTO Settings (Key, Value) VALUES ('RecordFolder', $folder);";
        insert.Parameters.AddWithValue("$folder", folder);
        insert.ExecuteNonQuery();
    }
    /// <summary>The cached reusable stream (TASK 5), or null if never created.
    /// Survives restarts so the pump has its RTMP URL the moment go-live starts
    /// instead of waiting on the YouTube round-trip.</summary>
    public ReusableStream? LoadReusableStream()
    {
        using var cmd = _connection.CreateCommand();
        cmd.CommandText = "SELECT Value FROM Settings WHERE Key = 'ReusableStream';";
        var value = cmd.ExecuteScalar() as string;
        if (string.IsNullOrWhiteSpace(value)) return null;
        var parts = value.Split('\u001F');
        return parts.Length == 3
            ? new ReusableStream(parts[0], parts[1], parts[2])
            : null;
    }
    public void SaveReusableStream(ReusableStream? stream)
    {
        using var cmd = _connection.CreateCommand();
        cmd.CommandText = "DELETE FROM Settings WHERE Key = 'ReusableStream';";
        cmd.ExecuteNonQuery();
        if (stream == null) return;
        using var insert = _connection.CreateCommand();
        insert.CommandText = "INSERT INTO Settings (Key, Value) VALUES ('ReusableStream', $value);";
        insert.Parameters.AddWithValue("$value", $"{stream.Id}\u001F{stream.IngestionAddress}\u001F{stream.StreamName}");
        insert.ExecuteNonQuery();
    }
    public string? LoadLicenseKey()
    {
        using var cmd = _connection.CreateCommand();
        cmd.CommandText = "SELECT Value FROM Settings WHERE Key = 'LicenseKey';";
        var value = cmd.ExecuteScalar() as string;
        return string.IsNullOrWhiteSpace(value) ? null : value;
    }
    public void SaveLicenseKey(string? key)
    {
        using var cmd = _connection.CreateCommand();
        cmd.CommandText = "DELETE FROM Settings WHERE Key = 'LicenseKey';";
        cmd.ExecuteNonQuery();
        if (string.IsNullOrWhiteSpace(key)) return;
        using var insert = _connection.CreateCommand();
        insert.CommandText = "INSERT INTO Settings (Key, Value) VALUES ('LicenseKey', $value);";
        insert.Parameters.AddWithValue("$value", key);
        insert.ExecuteNonQuery();
    }
    /// <summary>When the license was last validated online (ISO 8601), or null if never.</summary>
    public DateTime? LoadLicenseValidatedAt()
    {
        using var cmd = _connection.CreateCommand();
        cmd.CommandText = "SELECT Value FROM Settings WHERE Key = 'LicenseValidatedAt';";
        var value = cmd.ExecuteScalar() as string;
        if (string.IsNullOrWhiteSpace(value)) return null;
        return DateTime.TryParse(value, out var dt) ? dt : null;
    }
    public void SaveLicenseValidatedAt(DateTime? dt)
    {
        using var cmd = _connection.CreateCommand();
        cmd.CommandText = "DELETE FROM Settings WHERE Key = 'LicenseValidatedAt';";
        cmd.ExecuteNonQuery();
        if (dt == null) return;
        using var insert = _connection.CreateCommand();
        insert.CommandText = "INSERT INTO Settings (Key, Value) VALUES ('LicenseValidatedAt', $value);";
        insert.Parameters.AddWithValue("$value", dt.Value.ToString("o"));
        insert.ExecuteNonQuery();
    }
    /// <summary>Cached premium state (1 = premium, 0 = free). Used for offline
    /// grace period — the app checks online at startup but uses this cached
    /// value when offline.</summary>
    public bool LoadIsPremium()
    {
        using var cmd = _connection.CreateCommand();
        cmd.CommandText = "SELECT Value FROM Settings WHERE Key = 'IsPremium';";
        var value = cmd.ExecuteScalar() as string;
        return value == "1";
    }
    public void SaveIsPremium(bool isPremium)
    {
        using var cmd = _connection.CreateCommand();
        cmd.CommandText = "DELETE FROM Settings WHERE Key = 'IsPremium';";
        cmd.ExecuteNonQuery();
        using var insert = _connection.CreateCommand();
        insert.CommandText = "INSERT INTO Settings (Key, Value) VALUES ('IsPremium', $value);";
        insert.Parameters.AddWithValue("$value", isPremium ? "1" : "0");
        insert.ExecuteNonQuery();
    }
    public (string TransitionType, double DurationMs) LoadTransitionSettings()
    {
        using var cmd = _connection.CreateCommand();
        cmd.CommandText = "SELECT Value FROM Settings WHERE Key = 'TransitionType';";
        var type = cmd.ExecuteScalar() as string;
        using var cmd2 = _connection.CreateCommand();
        cmd2.CommandText = "SELECT Value FROM Settings WHERE Key = 'TransitionDurationMs';";
        var dur = cmd2.ExecuteScalar() as string;
        return (type ?? "Fade", dur != null && double.TryParse(dur, out var d) ? d : 300);
    }
    public void SaveTransitionSettings(string transitionType, double durationMs)
    {
        UpsertSetting("TransitionType", transitionType);
        UpsertSetting("TransitionDurationMs", durationMs.ToString("F0"));
    }
    // ─── Broadcast metadata (broadcast pull-out) + window geometry ───
    public Models.BroadcastMetadata LoadBroadcastMetadata()
    {
        return new Models.BroadcastMetadata
        {
            Title = GetSetting("Broadcast.Title") ?? string.Empty,
            Description = GetSetting("Broadcast.Description") ?? string.Empty,
            TagsCsv = GetSetting("Broadcast.TagsCsv") ?? string.Empty,
            Visibility = GetSetting("Broadcast.Visibility") ?? "private",
            MadeForKids = GetSetting("Broadcast.MadeForKids") == "1",
            ScheduledStartTime = DateTime.TryParse(GetSetting("Broadcast.ScheduledStartTime"), out var t) ? t : null,
        };
    }
    public void SaveBroadcastMetadata(Models.BroadcastMetadata meta)
    {
        UpsertSetting("Broadcast.Title", meta.Title);
        UpsertSetting("Broadcast.Description", meta.Description);
        UpsertSetting("Broadcast.TagsCsv", meta.TagsCsv);
        UpsertSetting("Broadcast.Visibility", meta.Visibility);
        UpsertSetting("Broadcast.MadeForKids", meta.MadeForKids ? "1" : "0");
        UpsertSetting("Broadcast.ScheduledStartTime",
            meta.ScheduledStartTime?.ToString("o") ?? string.Empty);
    }
    // ─── Hotkey bindings (TASK 20 step 2) ───
    /// <summary>
    /// Load saved hotkey bindings. Returns only entries that have been explicitly
    /// saved — missing HotkeyIds are unbound (not in the returned dictionary).
    /// Caller fills in defaults for any missing entries as needed.
    /// </summary>
    public Dictionary<HotkeyId, HotkeyChord> LoadHotkeyBindings()
    {
        var result = new Dictionary<HotkeyId, HotkeyChord>();
        foreach (HotkeyId id in Enum.GetValues(typeof(HotkeyId)))
        {
            var raw = GetSetting($"Hotkey.{id}");
            if (raw == null) continue; // not saved = unbound
            if (raw == "none") continue; // explicitly unbound
            try
            {
                result[id] = HotkeyChord.ParseStorage(raw);
            }
            catch (FormatException)
            {
                // corrupt entry — skip, will fall back to default
            }
        }
        return result;
    }
    /// <summary>
    /// Save hotkey bindings. Null entries in the dictionary mean "unbound" (stored
    /// as "none"). Only the provided entries are saved; previously saved entries
    /// for HotkeyIds not in the dictionary are deleted.
    /// </summary>
    public void SaveHotkeyBindings(Dictionary<HotkeyId, HotkeyChord?> bindings)
    {
        // Delete all existing hotkey settings first
        foreach (HotkeyId id in Enum.GetValues(typeof(HotkeyId)))
        {
            using var cmd = _connection.CreateCommand();
            cmd.CommandText = "DELETE FROM Settings WHERE Key = $key;";
            cmd.Parameters.AddWithValue("$key", $"Hotkey.{id}");
            cmd.ExecuteNonQuery();
        }
        // Save the new bindings
        foreach (var (id, chord) in bindings)
        {
            var value = chord?.ToString() ?? "none";
            UpsertSetting($"Hotkey.{id}", value);
        }
    }
    public (double Left, double Top, double Width, double Height, string State)? LoadWindowState()
    {
        var left = GetSetting("Window.Left");
        var top = GetSetting("Window.Top");
        var width = GetSetting("Window.Width");
        var height = GetSetting("Window.Height");
        var state = GetSetting("Window.State");
        if (left == null || top == null || width == null || height == null) return null;
        if (!double.TryParse(left, out var l) || !double.TryParse(top, out var t) ||
            !double.TryParse(width, out var w) || !double.TryParse(height, out var h))
            return null;
        return (l, t, w, h, state ?? "Normal");
    }
    public void SaveWindowState(double left, double top, double width, double height, string state)
    {
        UpsertSetting("Window.Left", left.ToString("F0"));
        UpsertSetting("Window.Top", top.ToString("F0"));
        UpsertSetting("Window.Width", width.ToString("F0"));
        UpsertSetting("Window.Height", height.ToString("F0"));
        UpsertSetting("Window.State", state);
    }
    public string? GetSetting(string key)
    {
        using var cmd = _connection.CreateCommand();
        cmd.CommandText = "SELECT Value FROM Settings WHERE Key = $key;";
        cmd.Parameters.AddWithValue("$key", key);
        return cmd.ExecuteScalar() as string;
    }
    public void UpsertSetting(string key, string value)
    {
        using var cmd = _connection.CreateCommand();
        cmd.CommandText = "DELETE FROM Settings WHERE Key = $key;";
        cmd.Parameters.AddWithValue("$key", key);
        cmd.ExecuteNonQuery();
        using var insert = _connection.CreateCommand();
        insert.CommandText = "INSERT INTO Settings (Key, Value) VALUES ($key, $value);";
        insert.Parameters.AddWithValue("$key", key);
        insert.Parameters.AddWithValue("$value", value);
        insert.ExecuteNonQuery();
    }
    internal const string AlertDefaultVideoKey = "AlertDefaultVideoAssetId";
    /// <summary>Stamps the shipped stream-alert placeholder clip (TASK 47): like any
    /// source image it lives as a BLOB in the internal Asset table, tracked by this
    /// Setting so the Save pruner keeps it alive. The creator's OWN replacement
    /// videos are never stored — they are plain path references (the 2026-09-26
    /// decision: the file the user picks stays at its real location on disk).
    /// <c>UpsertAsset</c> is hash-keyed, so re-stamping the same bytes returns the
    /// same id.</summary>
    public string EnsureAlertDefaultVideo(byte[] data)
    {
        var saved = GetSetting(AlertDefaultVideoKey);
        if (!string.IsNullOrWhiteSpace(saved) && GetAssetBytes(saved) != null)
            return saved;
        var id = UpsertAsset(data, 0, 0);
        UpsertSetting(AlertDefaultVideoKey, id);
        return id;
    }
    /// <summary>The stored default clip's Asset id, or null when never stamped.</summary>
    public string? GetAlertDefaultVideoId() => GetSetting(AlertDefaultVideoKey);
 }
@@ -0,0 +1,90 @@
 using Microsoft.Data.Sqlite;
 using ytLive.Models;
 namespace ytLive.Services;
 public partial class LayoutStore : IDisposable
 {
    // ─── YPP journey-tracker snapshots (TASK 39) ───
    /// <summary>Appends one YPP stats snapshot (append-only history; velocity/ETA
    /// read it in a later analytics slice).</summary>
    public void SaveYppSnapshot(YppStatSnapshot snapshot)
    {
        using var cmd = _connection.CreateCommand();
        cmd.CommandText = """
            INSERT INTO YppSnapshot (CapturedAtUtc, SubscriberCount, VideoCount, TotalViews,
                                     UploadsLast90Days, CommunityGuidelinesGoodStanding,
                                     CopyrightStrikesGoodStanding, ContentIdClaimsGoodStanding,
                                     OverallGoodStanding)
            VALUES ($captured, $subs, $videos, $views, $uploads, $cg, $cs, $cic, $overall);
            """;
        cmd.Parameters.AddWithValue("$captured", snapshot.CapturedAtUtc.ToString("o"));
        cmd.Parameters.AddWithValue("$subs", snapshot.SubscriberCount);
        cmd.Parameters.AddWithValue("$videos", snapshot.VideoCount);
        cmd.Parameters.AddWithValue("$views", snapshot.TotalViews);
        cmd.Parameters.AddWithValue("$uploads", snapshot.UploadsLast90Days);
        cmd.Parameters.AddWithValue("$cg", snapshot.CommunityGuidelinesGoodStanding ? 1 : 0);
        cmd.Parameters.AddWithValue("$cs", snapshot.CopyrightStrikesGoodStanding ? 1 : 0);
        cmd.Parameters.AddWithValue("$cic", snapshot.ContentIdClaimsGoodStanding ? 1 : 0);
        cmd.Parameters.AddWithValue("$overall", snapshot.OverallGoodStanding ? 1 : 0);
        cmd.ExecuteNonQuery();
    }
    /// <summary>Most recent snapshots, newest first (defaults to the full history).</summary>
    public List<YppStatSnapshot> LoadYppSnapshots(int limit = 365)
    {
        var result = new List<YppStatSnapshot>();
        using var cmd = _connection.CreateCommand();
        cmd.CommandText = """
            SELECT CapturedAtUtc, SubscriberCount, VideoCount, TotalViews, UploadsLast90Days,
                   CommunityGuidelinesGoodStanding, CopyrightStrikesGoodStanding,
                   ContentIdClaimsGoodStanding, OverallGoodStanding
            FROM YppSnapshot ORDER BY CapturedAtUtc DESC LIMIT $limit;
            """;
        cmd.Parameters.AddWithValue("$limit", limit);
        using var reader = cmd.ExecuteReader();
        while (reader.Read())
        {
            result.Add(new YppStatSnapshot
            {
                CapturedAtUtc = DateTime.TryParse(reader.GetString(0), out var captured) ? captured : DateTime.MinValue,
                SubscriberCount = reader.GetInt64(1),
                VideoCount = reader.GetInt64(2),
                TotalViews = reader.GetInt64(3),
                UploadsLast90Days = reader.GetInt32(4),
                CommunityGuidelinesGoodStanding = reader.GetInt32(5) != 0,
                CopyrightStrikesGoodStanding = reader.GetInt32(6) != 0,
                ContentIdClaimsGoodStanding = reader.GetInt32(7) != 0,
                OverallGoodStanding = reader.GetInt32(8) != 0,
            });
        }
        return result;
    }
    /// <summary>The manually self-reported YPP checklist state (2FA / AdSense are
    /// not readable from any YouTube API — the creator ticks them in-app).</summary>
    public (bool TwoFactorEnabled, bool AdSenseLinked) LoadYppChecklist()
    {
        return (GetSetting("Ypp.TwoFactorEnabled") == "1", GetSetting("Ypp.AdSenseLinked") == "1");
    }
    public void SaveYppChecklist(bool twoFactorEnabled, bool adsenseLinked)
    {
        UpsertSetting("Ypp.TwoFactorEnabled", twoFactorEnabled ? "1" : "0");
        UpsertSetting("Ypp.AdSenseLinked", adsenseLinked ? "1" : "0");
    }
    /// <summary>UTC timestamp of the last successful stats refresh (used to gate
    /// the once-daily auto-refresh against the analytics quota-thin API).</summary>
    public DateTime? LoadYppLastRefreshedAtUtc()
    {
        var value = GetSetting("Ypp.LastRefreshedAtUtc");
        return DateTime.TryParse(value, out var dt) ? dt : null;
    }
    public void SaveYppLastRefreshedAtUtc(DateTime utc)
    {
        UpsertSetting("Ypp.LastRefreshedAtUtc", utc.ToString("o"));
    }
 }
@@ -50,7 +50,9 @@ public sealed class MediaCaptureFrameSource : ICameraFrameSource
        // Fallback ladder: prefer the camera's VideoPreview stream, but if the
        // reader refuses to start there (NoVideoFrameAvailable), retry against
        // its VideoRecord stream — some devices only deliver through it.
-        // (MediaCaptureSharingMode.Exclusive is not projected by the 19041 SDK.)
+        // (The exclusive-lock upgrade is a separate, later unit — creator
        // ruling 2026-10-05; see HANDOFF.md. It is NOT blocked by an SDK gap:
        // `MediaCaptureSharingMode.ExclusiveControl` IS projected in 19041.)
        if (!await TryStartAsync(preferVideoRecord: false))
        {
            if (!await TryStartAsync(preferVideoRecord: true))
@@ -86,6 +88,20 @@ public sealed class MediaCaptureFrameSource : ICameraFrameSource
        }
    }
    /// <summary>
    /// Ordered reader-output-subtype candidates for a camera whose live media type
    /// is <paramref name="activeSubtype"/>. Bgra8 is the fast path (OnFrameArrived
    /// skips conversion) and works for uncompressed cameras; an MJPG-active source
    /// cannot be read as Bgra8 by a MediaFrameReader (no BGRA converter on the MJPG
    /// pipeline — StartAsync answers OutputFormatNotSupported), so MJPG leads with
    /// NV12 and falls back to the reader's default (null). Every candidate that is
    /// not Bgra8 is converted in OnFrameArrived.
    /// </summary>
    internal static string?[] ReaderSubtypeCandidates(string? activeSubtype) =>
        string.Equals(activeSubtype, "MJPG", StringComparison.OrdinalIgnoreCase)
            ? new string?[] { MediaEncodingSubtypes.Nv12, null }
            : new string?[] { MediaEncodingSubtypes.Bgra8, MediaEncodingSubtypes.Nv12, null };
    private async Task<bool> TryStartAsync(bool preferVideoRecord)
    {
        MediaCapture? capture = null;
@@ -102,6 +118,43 @@ public sealed class MediaCaptureFrameSource : ICameraFrameSource
            };
            await capture.InitializeAsync(settings);
            // MediaFrameReader defaults to the camera's FIRST media type — on UVC webcams
            // (Logitech C920 et al.) that is often YUY2 at a crippled rate (720p5!), and a
            // real-time 60fps container then shows a 5-20fps face cam as "every few frames
            // cut out". OBS's mechanism, available via VideoDeviceController (VideoProfile
            // is NOT projected in the 19041 SDK): negotiate the stream property. Pick the
            // best MJPEG >=640x360 @>=30fps (largest, fastest), set it BEFORE the frame
            // reader is created, fall back to device default on refusal, and log the live
            // media type so the next diagnosis starts from facts.
            try
            {
                var controller = capture.VideoDeviceController;
                var candidates = controller == null
                    ? new System.Collections.Generic.List<Windows.Media.MediaProperties.VideoEncodingProperties>()
                    : controller
                    .GetAvailableMediaStreamProperties(MediaStreamType.VideoPreview)
                    .OfType<Windows.Media.MediaProperties.VideoEncodingProperties>()
                    .Where(v => string.Equals(v.Subtype, "MJPG", StringComparison.OrdinalIgnoreCase)
                                && v.Width >= 640 && v.Height >= 360
                                && v.FrameRate.Denominator > 0
                                && v.FrameRate.Numerator / v.FrameRate.Denominator >= 30.0)
                    .OrderByDescending(v => v.FrameRate.Numerator / (double)Math.Max(1, v.FrameRate.Denominator))
                    .ThenByDescending(v => (long)v.Width * v.Height)
                    .ToList();
                if (candidates.Count > 0)
                {
                    var pick = candidates
                        .OrderBy(v => (long)v.Width * v.Height)
                        .LastOrDefault(v => v.Width <= 1280) ?? candidates[0];
                    await controller!.SetMediaStreamPropertiesAsync(MediaStreamType.VideoPreview, pick);
                }
            }
            catch (Exception fmtEx)
            {
                AppLog.Write($"MediaCaptureFrameSource: MJPG negotiation refused ({fmtEx.Message}); " +
                             "keeping device-default media type");
            }
            // Post-init resource validation: the capture must actually be bound to
            // the device we asked for and must expose a live video controller.
            if (!string.Equals(capture.MediaCaptureSettings?.VideoDeviceId, _deviceId,
@@ -143,21 +196,82 @@ public sealed class MediaCaptureFrameSource : ICameraFrameSource
            capture.Failed += OnCaptureFailed;
            capture.CameraStreamStateChanged += OnCameraStreamStateChanged;
-            reader = await capture.CreateFrameReaderAsync(colorSource, MediaEncodingSubtypes.Bgra8);
+            // The reader must output a subtype the source can actually produce, else
-            if (reader == null)
+            // StartAsync refuses (OutputFormatNotSupported). An uncompressed camera
-                throw new InvalidOperationException($"Camera '{_deviceId}' created no frame reader.");
+            // converts to Bgra8 fine (the fast path); a camera sitting in MJPG — which
            // is what we find when ANOTHER app left it there and ours can't re-negotiate
            // under SharedReadOnly contention — cannot be read as Bgra8 by a
            // MediaFrameReader (the MJPG pipeline exposes NV12 output, not BGRA). Walk
            // the candidate ladder; anything that isn't Bgra8 is converted in
            // OnFrameArrived anyway.
            string? activeSubtype = null;
            try
            {
                var active = capture.VideoDeviceController?
                    .GetMediaStreamProperties(colorSource.Info.MediaStreamType);
                if (active is Windows.Media.MediaProperties.VideoEncodingProperties vep)
                {
                    activeSubtype = vep.Subtype;
                    AppLog.Write($"Camera '{_deviceId}' media type: {vep.Subtype} " +
                                 $"{vep.Width}x{vep.Height} @ {vep.FrameRate.Numerator}/{vep.FrameRate.Denominator}fps");
                }
            }
            catch { /* logging must never kill acquisition */ }
-            reader.FrameArrived += OnFrameArrived;
+            // Each candidate is allocated AND started under its own catch: a WinRT
-            var status = await reader.StartAsync();
+            // call answering an unsupported subtype can THROW (E_INVALIDARG / "value
-            if (status != MediaFrameReaderStartStatus.Success)
+            // does not fall within the expected range") instead of returning a start
-                throw new InvalidOperationException(
+            // status, so every throw must degrade to the next candidate — never let
-                    $"Camera '{_deviceId}' frame reader refused to start: {status}.");
+            // one rejected format abort the whole acquisition. Individual rejections
            // are logged and collected; only the last-resort net below (the outer
            // try/catch of this method) keeps cowboying device-level errors.
            var refused = new List<string>();
            foreach (var outputSubtype in ReaderSubtypeCandidates(activeSubtype))
            {
                var attempt = outputSubtype ?? "<default>";
                try
                {
                    reader = outputSubtype is null
                        ? await capture.CreateFrameReaderAsync(colorSource)
                        : await capture.CreateFrameReaderAsync(colorSource, outputSubtype);
                    if (reader == null)
                    {
                        refused.Add($"{attempt}: no frame reader");
                        continue;
                    }
-            _capture = capture;
+                    reader.FrameArrived += OnFrameArrived;
-            _frameReader = reader;
+                    var status = await reader.StartAsync();
-            _lastError = null;
+                    if (status == MediaFrameReaderStartStatus.Success)
-            _isFailed = false;
+                    {
-            return true;
+                        _capture = capture;
                        _frameReader = reader;
                        _lastError = null;
                        _isFailed = false;
                        StartCadenceWindow();
                        return true;
                    }
                    reader.FrameArrived -= OnFrameArrived;
                    reader.Dispose();
                    reader = null;
                    refused.Add($"{attempt}: {status}");
                }
                catch (Exception ex)
                {
                    AppLog.Write($"MediaCaptureFrameSource: reader as '{attempt}' refused: {ex.Message}");
                    if (reader != null)
                    {
                        reader.FrameArrived -= OnFrameArrived;
                        reader.Dispose();
                        reader = null;
                    }
                    refused.Add($"{attempt}: {ex.Message}");
                }
            }
            throw new InvalidOperationException(
                $"Camera '{_deviceId}' frame reader refused to start: {string.Join(", ", refused)}.");
        }
        catch (Exception ex)
        {
@@ -176,6 +290,30 @@ public sealed class MediaCaptureFrameSource : ICameraFrameSource
        }
    }
    private const int CadenceWindowSeconds = 5;
    private void StartCadenceWindow()
    {
        _arrivalCadence.Reset();
        _cameraCadence.Reset();
        _cadenceNextReportTicks = System.Diagnostics.Stopwatch.GetTimestamp()
            + System.Diagnostics.Stopwatch.Frequency * CadenceWindowSeconds;
    }
    /// <summary>Logs one cadence window and opens the next. The size rides along
    /// because the whole question started as "the webcam is soft": a future format
    /// change must be readable in the SAME line that proves the frame rate.</summary>
    private void ReportCadence(int width, int height)
    {
        _cadenceNextReportTicks = System.Diagnostics.Stopwatch.GetTimestamp()
            + System.Diagnostics.Stopwatch.Frequency * CadenceWindowSeconds;
        var arrivals = _arrivalCadence.Summarize();
        var camera = _cameraCadence.Summarize();
        _arrivalCadence.Reset();
        _cameraCadence.Reset();
        AppLog.Write($"Camera cadence {width}x{height}: {arrivals.Describe("arrivals")} | {camera.Describe("camera")}");
    }
    private void UnsubscribeCaptureEvents(MediaCapture capture)
    {
        capture.Failed -= OnCaptureFailed;
@@ -209,12 +347,64 @@ public sealed class MediaCaptureFrameSource : ICameraFrameSource
        }
    }
    // Buffer recycling (same lesson as the screen capture): a fresh ~3.7MB byte[]
    // per device frame at 30-60fps is 110-220MB/s of LOH churn — gen2 pauses land
    // on the frame pump as 35-40ms render spikes. An 8-deep ring (take-14 rule:
    // depth × source period must exceed the worst consumer hold), rotated on the
    // single frame-reader thread, with per-frame Epoch so the identity-keyed paste
    // cache can never serve a recycled array as unchanged.
    private readonly byte[]?[] _frameRing = new byte[8][];
    private int _ringNext;
    private long _epoch;
    private byte[] RentRingBuffer(int size)
    {
        for (var tries = 0; tries < _frameRing.Length; tries++)
        {
            var idx = (_ringNext + tries) % _frameRing.Length;
            var buf = _frameRing[idx];
            if (buf != null && buf.Length == size)
            {
                _ringNext = (idx + 1) % _frameRing.Length;
                return buf;
            }
        }
        var slot = _ringNext;
        _ringNext = (slot + 1) % _frameRing.Length;
        var fresh = new byte[size];
        _frameRing[slot] = fresh;
        return fresh;
    }
    // Arrival vs production cadence (UNIT 0, 2026-10-05): the recorded file cannot
    // tell a dropped camera frame from a padded repeat — rawvideo stamps frames by
    // ARRIVAL at the declared 60fps, so a webcam delivering 25 of its 30 frames still
    // muxes a full-length file. Two counters, one reader, settle it: the camera's OWN
    // SystemRelativeTime stamps (device/USB/driver cadence) against the moment the
    // reader handed each frame to us (our cadence, including coalescing drops — the
    // reader deliberately keeps only the LATEST frame, so falling behind is silent).
    // Steady camera + ragged arrivals = we are behind. Ragged in both = the device.
    private readonly FrameCadence _arrivalCadence = new();
    private readonly FrameCadence _cameraCadence = new();
    private long _cadenceNextReportTicks;
    private void OnFrameArrived(MediaFrameReader sender, MediaFrameArrivedEventArgs args)
    {
        var arrivedTicks = System.Diagnostics.Stopwatch.GetTimestamp();
        using var frame = sender.TryAcquireLatestFrame();
        var videoFrame = frame?.VideoMediaFrame?.SoftwareBitmap;
        if (videoFrame == null) return;
        // SystemRelativeTime is QPC-domain, the same clock Stopwatch reads here, so the
        // camera's own frame spacing is measurable without a second conversion. It is
        // NULLABLE in the projection (null = the device supplied no stamp), so the
        // production side of the comparison is then simply missing from the line —
        // arrivals alone still measure what reached us.
        _arrivalCadence.Add(arrivedTicks);
        if (frame!.SystemRelativeTime is { } cameraStamp)
            _cameraCadence.Add((long)(cameraStamp.TotalSeconds * System.Diagnostics.Stopwatch.Frequency));
        if (arrivedTicks >= _cadenceNextReportTicks) ReportCadence(videoFrame.PixelWidth, videoFrame.PixelHeight);
        var bitmap = videoFrame.BitmapPixelFormat == BitmapPixelFormat.Bgra8
            ? videoFrame
            : SoftwareBitmap.Convert(videoFrame, BitmapPixelFormat.Bgra8);
@@ -225,9 +415,14 @@ public sealed class MediaCaptureFrameSource : ICameraFrameSource
            using var reference = buffer.CreateReference();
            if (WindowsRuntimeMarshal.TryGetDataUnsafe(reference, out var pixelsPtr, out var capacity))
            {
-                var pixels = new byte[capacity];
+                var pixels = RentRingBuffer((int)capacity);
                Marshal.Copy(pixelsPtr, pixels, 0, (int)capacity);
-                FrameAvailable?.Invoke(new VideoFrame(bitmap.PixelWidth, bitmap.PixelHeight, pixels));
+
                // MediaCapture video carries no alpha plane — the OS fills 255.
                var outFrame = new VideoFrame(bitmap.PixelWidth, bitmap.PixelHeight, pixels)
                    { IsOpaque = true, Epoch = ++_epoch };
                FrameAvailable?.Invoke(outFrame);
            }
        }
        catch (Exception ex)
@@ -0,0 +1,147 @@
 using System.Diagnostics;
 using System.IO;
 using ytLive.Services.Encoder;
 namespace ytLive.Services;
 /// <summary>
 /// TASK 21: decodes a local media file (any format ffmpeg handles) into
 /// <see cref="VideoFrame"/>s for a MediaSource. Implements
 /// <see cref="IMediaFrameSource"/>: raises <see cref="FrameAvailable"/> per
 /// frame and <see cref="IMediaFrameSource.Completed"/> on natural EOF (unless
 /// <see cref="IMediaFrameSource.Looping"/>). Spawns ffmpeg with
 /// <c>-f rawvideo -pix_fmt bgra</c> and drains the raw BGRA pipe via
 /// <see cref="RawVideoFrameReader"/>. The decoder process and emitters are seams
 /// so tests run without a real codec or audio device.
 /// </summary>
 public sealed class MediaVideoSource : IMediaFrameSource
 {
    public event Action<VideoFrame>? FrameAvailable;
    public event Action? Completed;
    public string Key => _path;
    public bool Looping { get; set; }
    private readonly string _path;
    private readonly int _width;
    private readonly int _height;
    private readonly IFfmpegLocator _locator;
    private readonly Func<IDecodeProcess> _processFactory;
    private readonly IFrameRateProbe? _probe;
    private readonly Func<TimeSpan, CancellationToken, Task> _delay;
    private readonly CancellationTokenSource _cts = new();
    private IDisposable? _run;
    private IDecodeProcess? _active;
    public MediaVideoSource(
        string path,
        int width,
        int height,
        IFfmpegLocator locator,
        Func<IDecodeProcess> processFactory,
        IFrameRateProbe? frameRateProbe = null,
        Func<TimeSpan, CancellationToken, Task>? delay = null)
    {
        _path = path;
        _width = width;
        _height = height;
        _locator = locator;
        _processFactory = processFactory;
        _probe = frameRateProbe;
        _delay = delay ?? ((t, ct) => Task.Delay(t, ct));
    }
    public Task StartAsync(CancellationToken cancellationToken = default)
    {
        if (_run != null) return Task.CompletedTask;
        _run = _cts.Token.Register(StopInternal);
        _ = Task.Run(RunAsync, CancellationToken.None);
        return Task.CompletedTask;
    }
    public Task StopAsync()
    {
        _cts.Cancel();
        _run = null;
        return Task.CompletedTask;
    }
    public void Dispose()
    {
        _cts.Cancel();
        _cts.Dispose();
        _active?.Dispose();
    }
    private void StopInternal() => KillProcess();
    private async Task RunAsync()
    {
        try
        {
            double? frameRate = null;
            if (_probe != null)
                frameRate = await _probe.ProbeAsync(_path, _cts.Token).ConfigureAwait(false);
            var frameDuration = frameRate is > 0 ? TimeSpan.FromSeconds(1.0 / frameRate.Value) : TimeSpan.Zero;
            var ffmpegPath = await _locator.LocateAsync(_cts.Token).ConfigureAwait(false);
            var args =
                $"-hide_banner -loglevel error -i \"{_path}\" " +
                $"-f rawvideo -pix_fmt bgra -vf scale={_width}:{_height} -an -";
            var startInfo = new ProcessStartInfo
            {
                FileName = ffmpegPath,
                Arguments = args,
                UseShellExecute = false,
                RedirectStandardOutput = true,
                RedirectStandardError = true,
                CreateNoWindow = true,
            };
            do
            {
                using (var process = _processFactory())
                {
                    _active = process;
                    process.Start(startInfo);
                    var reader = new RawVideoFrameReader(_width, _height);
                    var buffer = new byte[65536];
                    var stream = process.StandardOutput;
                    while (!_cts.IsCancellationRequested && !process.HasExited)
                    {
                        var read = await stream.ReadAsync(buffer, 0, buffer.Length, _cts.Token).ConfigureAwait(false);
                        if (read <= 0) break;
                        foreach (var frame in reader.Feed(buffer.AsSpan(0, read).ToArray()))
                        {
                            FrameAvailable?.Invoke(frame);
                            if (frameDuration > TimeSpan.Zero)
                                await _delay(frameDuration, _cts.Token).ConfigureAwait(false);
                        }
                    }
                }
                _active = null;
            }
            while (Looping && !_cts.IsCancellationRequested);
        }
        catch (OperationCanceledException)
        {
        }
        catch (Exception ex)
        {
            Fail($"Media decode failed: {ex.Message}");
            return;
        }
        if (!_cts.IsCancellationRequested)
            Completed?.Invoke();
    }
    private void Fail(string message) => Console.Error.WriteLine(message);
    private void KillProcess()
    {
        try { _active?.Kill(); } catch { /* already exited */ }
    }
 }
@@ -0,0 +1,256 @@
 using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
 using System.Windows;
 using System.Windows.Media;
 using System.Windows.Media.Imaging;
 using System.Windows.Threading;
 using ytLive.Helpers;
 namespace ytLive.Services;
 /// <summary>
 /// TASK 21: owns media-file decode sessions app-wide, refcounted by file path.
 /// One file = at most one decoder, one shared WriteableBitmap; the last release
 /// stops and disposes the source. Frames arrive on a worker thread and are
 /// coalesced onto the UI dispatcher (at most one pending copy per session, using
 /// the latest frame). Mirrors ScreenCaptureManager/CameraManager.
 /// </summary>
 public sealed class MediaVideoSourceManager : IDisposable
 {
    private sealed class MediaSession
    {
        public string Key { get; }
        public IMediaFrameSource Source { get; }
        public Action<VideoFrame>? FrameHandler;
        public int RefCount;
        public bool Started;
        public WriteableBitmap? PreviewBitmap;
        public VideoFrame? LatestFrame;
        public bool FramePending;
        public MediaSession(string key, IMediaFrameSource source)
        {
            Key = key;
            Source = source;
            RefCount = 1;
        }
    }
    private readonly Func<string, IMediaFrameSource?> _sourceFactory;
    private readonly Dispatcher? _uiDispatcher;
    private readonly Dictionary<string, MediaSession> _sessions = new();
    private readonly object _gate = new();
    /// <summary>Raised on the UI thread when a media file's shared preview bitmap is first created.</summary>
    public event Action<string, WriteableBitmap>? PreviewBitmapChanged;
    /// <summary>Raised when a media decoder cannot be created (bad path).</summary>
    public event Action<string, string>? MediaFailed;
    public MediaVideoSourceManager(Func<string, IMediaFrameSource?> sourceFactory, Dispatcher? uiDispatcher = null)
    {
        _sourceFactory = sourceFactory;
        _uiDispatcher = uiDispatcher;
    }
    /// <summary>Increments the refcount for a file, starting the decoder the first time.</summary>
    public async Task<bool> AcquireAsync(string key)
    {
        if (string.IsNullOrWhiteSpace(key)) return false;
        MediaSession session;
        bool shouldStart;
        lock (_gate)
        {
            if (_sessions.TryGetValue(key, out var existing))
            {
                existing.RefCount++;
                shouldStart = false;
                session = existing;
            }
            else
            {
                IMediaFrameSource? source;
                try
                {
                    source = _sourceFactory(key);
                }
                catch (Exception ex)
                {
                    AppLog.Write($"MediaSource: creating decoder '{key}' failed: {ex.Message}");
                    MediaFailed?.Invoke(key, ex.Message);
                    return false;
                }
                if (source == null)
                {
                    MediaFailed?.Invoke(key, "No decoder for this file");
                    return false;
                }
                session = new MediaSession(key, source);
                session.FrameHandler = frame => OnFrameAvailable(session, frame);
                session.Source.FrameAvailable += session.FrameHandler;
                _sessions[key] = session;
                shouldStart = true;
            }
        }
        if (!shouldStart) return session.Started;
        try
        {
            await session.Source.StartAsync();
            session.Started = true;
            return true;
        }
        catch (Exception ex)
        {
            lock (_gate)
                _sessions.Remove(key);
            session.Source.FrameAvailable -= session.FrameHandler;
            AppLog.Write($"MediaSource: failed to start decoder '{key}': {ex.Message}");
            MediaFailed?.Invoke(key, ex.Message);
            await SafeStopAsync(session.Source);
            return false;
        }
    }
    public async Task ReleaseAsync(string key)
    {
        MediaSession? toStop = null;
        lock (_gate)
        {
            if (!_sessions.TryGetValue(key, out var session)) return;
            if (--session.RefCount > 0) return;
            _sessions.Remove(key);
            toStop = session;
        }
        if (toStop == null) return;
        toStop.Source.FrameAvailable -= toStop.FrameHandler;
        await SafeStopAsync(toStop.Source);
        toStop.PreviewBitmap = null;
    }
    /// <summary>Releases a file unconditionally (every ref) — used on layout reloads.</summary>
    public async Task ReleaseAllAsync(string key)
    {
        MediaSession? toStop = null;
        lock (_gate)
        {
            if (!_sessions.TryGetValue(key, out var session)) return;
            session.RefCount = 0;
            _sessions.Remove(key);
            toStop = session;
        }
        if (toStop == null) return;
        toStop.Source.FrameAvailable -= toStop.FrameHandler;
        await SafeStopAsync(toStop.Source);
        toStop.PreviewBitmap = null;
    }
    /// <summary>The most recent decoded frame for a file, or null before the first
    /// frame (or if the file has no session). The live compositor reads media from here.</summary>
    public VideoFrame? GetLatestFrame(string key)
    {
        lock (_gate)
            return _sessions.TryGetValue(key, out var session) ? session.LatestFrame : null;
    }
    /// <summary>The shared preview bitmap for a file (so a config created after the
    /// first frame can adopt the running bitmap), or null.</summary>
    public WriteableBitmap? GetPreviewBitmap(string key)
    {
        lock (_gate)
            return _sessions.TryGetValue(key, out var session) ? session.PreviewBitmap : null;
    }
    public void Dispose()
    {
        List<MediaSession> sessions;
        lock (_gate)
        {
            sessions = new List<MediaSession>(_sessions.Values);
            _sessions.Clear();
        }
        foreach (var session in sessions)
        {
            session.Source.FrameAvailable -= session.FrameHandler;
            _ = SafeStopAsync(session.Source);
        }
    }
    private static async Task SafeStopAsync(IMediaFrameSource source)
    {
        try
        {
            await source.StopAsync();
        }
        catch (Exception ex)
        {
            AppLog.Write($"MediaSource: stopping decoder failed: {ex.Message}");
        }
    }
    private bool TryGetActiveSession(MediaSession session)
    {
        lock (_gate)
            return _sessions.TryGetValue(session.Key, out var current) && ReferenceEquals(current, session);
    }
    private void OnFrameAvailable(MediaSession session, VideoFrame frame)
    {
        if (!TryGetActiveSession(session)) return;
        session.LatestFrame = frame;
        if (session.PreviewBitmap == null)
        {
            if (_uiDispatcher == null) return;
            if (_uiDispatcher.CheckAccess())
                EnsurePreviewBitmap(session);
            else
                _uiDispatcher.BeginInvoke(() =>
                {
                    if (TryGetActiveSession(session))
                        EnsurePreviewBitmap(session);
                }, DispatcherPriority.Render);
            return;
        }
        if (_uiDispatcher == null || _uiDispatcher.CheckAccess())
        {
            CopyFrame(session);
            return;
        }
        if (session.FramePending) return;
        session.FramePending = true;
        _uiDispatcher.BeginInvoke(() =>
        {
            session.FramePending = false;
            if (TryGetActiveSession(session) && session.PreviewBitmap != null)
                CopyFrame(session);
        }, DispatcherPriority.Render);
    }
    private void EnsurePreviewBitmap(MediaSession session)
    {
        if (session.PreviewBitmap != null || session.LatestFrame == null) return;
        var frame = session.LatestFrame;
        var bitmap = new WriteableBitmap(frame.Width, frame.Height, 96, 96, PixelFormats.Bgra32, null);
        bitmap.WritePixels(new Int32Rect(0, 0, frame.Width, frame.Height), frame.BgraPixels, frame.Stride, 0);
        session.PreviewBitmap = bitmap;
        PreviewBitmapChanged?.Invoke(session.Key, bitmap);
    }
    private void CopyFrame(MediaSession session)
    {
        var bitmap = session.PreviewBitmap;
        var frame = session.LatestFrame;
        if (bitmap == null || frame == null) return;
        if (frame.Width != bitmap.PixelWidth || frame.Height != bitmap.PixelHeight) return;
        bitmap.WritePixels(new Int32Rect(0, 0, frame.Width, frame.Height), frame.BgraPixels, frame.Stride, 0);
    }
 }
@@ -0,0 +1,30 @@
 using System;
 using System.Threading;
 namespace ytLive.Services;
 /// <summary>
 /// An atomic "publish only if strictly newer" gate for the capture's latest-wins
 /// hand-out. Screen capture conversions may now overlap (slice 17), so two
 /// conversions can finish briefly out of order; without a monotonic gate the slower
 /// (older) completion would overwrite the faster (newer) one's LatestFrame and the
 /// compositor would render STALE content — a time hole in the other direction.
 /// Sequence must be a strictly increasing per-source counter
 /// (<c>Interlocked.Increment</c> in <c>ScreenCaptureFrameSource</c>).
 /// </summary>
 internal sealed class MonotonicGate
 {
    private long _last;
    /// <summary>Returns true iff <paramref name="seq"/> is strictly newer than every
    /// seq accepted so far (and records it).</summary>
    public bool TryPublish(long seq)
    {
        while (true)
        {
            var current = Interlocked.Read(ref _last);
            if (seq <= current) return false;
            if (Interlocked.CompareExchange(ref _last, seq, current) == current) return true;
        }
    }
 }
@@ -0,0 +1,59 @@
 namespace ytLive.Services;
 /// <summary>
 /// TASK 21: parses a stream of tightly-packed raw BGRA frames into
 /// <see cref="VideoFrame"/>s. The consumer of an ffmpeg <c>-f rawvideo -pix_fmt
 /// bgra</c> stdout pipe: every frame is exactly <c>width*height*4</c> bytes, so a
 /// frame is emitted whenever that many bytes have accumulated. Pure and fully
 /// deterministic, so it is tested with a synthetic byte stream — no ffmpeg, no
 /// process, no audio device needed.
 /// </summary>
 public sealed class RawVideoFrameReader
 {
    private readonly int _frameBytes;
    private readonly int _width;
    private readonly int _height;
    private byte[]? _pending;
    public RawVideoFrameReader(int width, int height)
    {
        _width = width;
        _height = height;
        _frameBytes = width * height * 4;
    }
    /// <summary>Feeds <paramref name="bytes"/> read from the pipe and returns any
    /// whole frames reconstructed so far. Partial/pending bytes are kept for the
    /// next call — frames never split or merge across reads.</summary>
    public List<VideoFrame> Feed(byte[] bytes)
    {
        var pending = _pending;
        byte[] combined;
        if (pending != null && pending.Length > 0)
        {
            combined = new byte[pending.Length + bytes.Length];
            Buffer.BlockCopy(pending, 0, combined, 0, pending.Length);
            Buffer.BlockCopy(bytes, 0, combined, pending.Length, bytes.Length);
            _pending = null;
        }
        else
        {
            combined = bytes;
        }
        var frames = new List<VideoFrame>();
        var offset = 0;
        while (combined.Length - offset >= _frameBytes)
        {
            var frame = new byte[_frameBytes];
            Buffer.BlockCopy(combined, offset, frame, 0, _frameBytes);
            frames.Add(new VideoFrame(_width, _height, frame));
            offset += _frameBytes;
        }
        if (offset < combined.Length)
            _pending = combined[offset..];
        return frames;
    }
 }
@@ -2,11 +2,17 @@ namespace ytLive.Services;
 /// <summary>
 /// Pure filename logic for local recordings (TASK 18). The user-requested naming
-/// is <c>ty-yyyymmdd-hhmm-hh2mm2.mp4</c>: <c>ty</c> is the brand marker, the first
+/// is <c>ty-yyyymmdd-hhmm-fff-hh2mm2.mp4</c>: <c>ty</c> is the brand marker, the first
-/// <c>hhmm</c> is the hour+minute the recording STARTED (saved), and the second
+/// <c>hhmm</c> is the hour+minute the recording STARTED (saved), <c>fff</c> is
-/// <c>hh2mm2</c> is the hour+minute of the recording's LENGTH. Length is only known
+/// milliseconds on the same start timestamp, and the last <c>hh2mm2</c> is the
-/// when recording ends, so the file is created with a <c>0000</c> length and renamed
+/// hour+minute of the recording's LENGTH. Length is only known when recording ends,
-/// on stop (see <see cref="FinalizeFileName"/>).
+/// so the file is created with a <c>0000</c> length and renamed on stop (see
 /// <see cref="FinalizeFileName"/>).
 /// <para>The <c>fff</c> exists so two instances started in the same minute cannot
 /// compute the same path — the dev multi-instance use case (record one instance
 /// with the other) would otherwise have both ffmpeg processes writing one file.
 /// Both names derive from the same <c>_recordStartTime</c>, so the segment survives
 /// the rename.</para>
 /// </summary>
 public static class RecordingFile
 {
@@ -14,14 +20,14 @@ public static class RecordingFile
    public const string StartLengthSuffix = "0000";
    public static string BuildStartName(DateTime start)
-        => $"ty-{start:yyyyMMdd}-{start:HHmm}-{StartLengthSuffix}";
+        => $"ty-{start:yyyyMMdd}-{start:HHmm}-{start:fff}-{StartLengthSuffix}";
    /// <summary>Final name with the real recording length (fractional hour+minute),
-    /// e.g. 75 minutes → <c>ty-20260829-1405-0115.mp4</c>.</summary>
+    /// e.g. 75 minutes → <c>ty-20260829-1405-000-0115.mp4</c>.</summary>
    public static string BuildFinalName(DateTime start, TimeSpan length)
    {
        var hh2 = (int)length.TotalHours;
        var mm2 = length.Minutes;
-        return $"ty-{start:yyyyMMdd}-{start:HHmm}-{hh2:00}{mm2:00}";
+        return $"ty-{start:yyyyMMdd}-{start:HHmm}-{start:fff}-{hh2:00}{mm2:00}";
    }
 }
@@ -0,0 +1,159 @@
 using System;
 using System.Collections.Generic;
 using System.Collections.ObjectModel;
 using System.Linq;
 using ytLive.Models;
 using ytLive.Services.Compositor;
 namespace ytLive.Services;
 /// <summary>
 /// The scene graph (TASK 31): single owner of the scene collection and the
 /// element inventory / mutation surface, plus the static/dynamic classification
 /// queries the compositor optimization depends on.
 ///
 /// Scenes are referenced (not owned): the same <see cref="Scene"/> instances live
 /// on the ViewModel's bindable surface; SceneGraph adds/removes/reorders their
 /// <see cref="Scene.Elements"/> and answers queries (background / webcam / chat /
 /// split point) that used to be scattered LINQ across MainViewModel.
 ///
 /// Classification: <see cref="ElementKind.Static"/> (images, background art) is
 /// baked once; <see cref="ElementKind.Dynamic"/> (webcam, live capture, chat, web)
 /// is composited per frame. The <b>split point</b> is the index of the first
 /// dynamic element — everything below it forms the baked base.
 /// </summary>
 public sealed class SceneGraph
 {
    private readonly Dictionary<string, SceneRegion> _regionCache = new(StringComparer.Ordinal);
    private readonly object _gate = new();
    /// <summary>The shared scene collection (same instances the ViewModel binds).</summary>
    public ObservableCollection<Scene> Scenes { get; } = new();
    /// <summary>The one Background row for a scene — null when the scene has none.</summary>
    public Source? GetBackground(Scene scene)
        => scene.Elements.OfType<Source>().FirstOrDefault(s => s.IsBackground);
    /// <summary>This scene's webcam usage, if any.</summary>
    public WebcamSceneConfig? GetWebcam(Scene scene)
        => scene.Elements.OfType<WebcamSceneConfig>().FirstOrDefault();
    /// <summary>All chat-box elements across every scene (for ChatOverlayLayer).</summary>
    public IEnumerable<Source> GetChatBoxes()
        => Scenes.SelectMany(s => s.Elements.OfType<Source>().Where(x => x.Type == SourceType.ChatBox));
    /// <summary>Index of the first dynamic element (the split point). If no dynamic
    /// element exists this equals <see cref="Scene.Elements"/> count — fully baked.</summary>
    public int GetSplitPoint(Scene scene)
    {
        var elements = scene.Elements;
        for (var i = 0; i < elements.Count; i++)
        {
            if (elements[i].Kind == ElementKind.Dynamic)
                return i;
        }
        return elements.Count;
    }
    /// <summary>True when the whole scene is static (no dynamic element) — the
    /// compositor can bake it once and skip per-frame compositing.</summary>
    public bool IsStatic(Scene scene)
        => scene.Elements.All(e => e.Kind == ElementKind.Static);
    /// <summary>Invalidate the cached bake region for a scene after any mutation
    /// (element add/remove/reorder, static resize/opacity/visibility, asset change).</summary>
    public void InvalidateBake(Scene scene)
    {
        lock (_gate) _regionCache.Remove(scene.Id);
    }
    // ─── Mutation surface (single owner of element operations) ───
    /// <summary>Append an element to a scene and (re)bake accordingly.</summary>
    public void AddElement(Scene scene, SceneElement element)
    {
        scene.Elements.Add(element);
        InvalidateBake(scene);
    }
    /// <summary>Insert an element at a specific z-index and (re)bake accordingly.</summary>
    public void InsertElement(Scene scene, int index, SceneElement element)
    {
        scene.Elements.Insert(index, element);
        InvalidateBake(scene);
    }
    /// <summary>Remove an element and (re)bake accordingly.</summary>
    public bool RemoveElement(Scene scene, SceneElement element)
    {
        var removed = scene.Elements.Remove(element);
        if (removed) InvalidateBake(scene);
        return removed;
    }
    /// <summary>Reorder an element in z-space and (re)bake accordingly.</summary>
    public void MoveElement(Scene scene, SceneElement element, int newIndex)
    {
        var current = scene.Elements.IndexOf(element);
        if (current < 0) return;
        scene.Elements.Move(current, newIndex);
        InvalidateBake(scene);
    }
    /// <summary>Add a scene to the collection (wiring is handled by the ViewModel).</summary>
    public void AddScene(Scene scene) => Scenes.Add(scene);
    /// <summary>Get (or bake) the cached static base for a scene. Null means "no static
    /// base" (first layer is dynamic or the scene is empty) — caller falls back to full render.</summary>
    public VideoFrame? GetBakedBase(
        Scene scene,
        Func<SceneElement, VideoFrame?> frameFor,
        Func<CompositorOptions> options,
        VideoFrame? socialBarFrame = null,
        int socialBarTop = 0,
        VideoFrame? flashFrame = null)
    {
        var split = GetSplitPoint(scene);
        if (split == 0) return null;
        lock (_gate)
        {
            if (_regionCache.TryGetValue(scene.Id, out var cached)
                && cached.Matches(scene, split))
                return cached.Frame;
        }
        var baked = SceneCompositor.BakeStaticBase(
            scene, split, frameFor, options, socialBarFrame, socialBarTop, flashFrame);
        if (baked == null) return null;
        lock (_gate)
        {
            _regionCache[scene.Id] = new SceneRegion(baked, scene.Elements.Take(split).ToList());
        }
        return baked;
    }
    /// <summary>The baked frame + the element identity it was baked from (for invalidation).</summary>
    private sealed class SceneRegion
    {
        public VideoFrame Frame { get; }
        private readonly string[] _staticElementIds;
        public SceneRegion(VideoFrame frame, List<SceneElement> staticBelow)
        {
            Frame = frame;
            _staticElementIds = staticBelow.Select(e => e.Id).ToArray();
        }
        /// <summary>Only static layers below the split are part of the base. Two bakes
        /// match iff the same static element identities, in the same order, are below
        /// the split — dynamic-only pixel/layout changes never invalidate.</summary>
        public bool Matches(Scene scene, int split)
        {
            var below = scene.Elements.Take(split).Select(e => e.Id).ToArray();
            return below.Length == _staticElementIds.Length
                && below.SequenceEqual(_staticElementIds);
        }
    }
 }
@@ -1,6 +1,8 @@
 using System;
 using System.Diagnostics;
 using System.Runtime.InteropServices;
 using System.Runtime.InteropServices.WindowsRuntime;
 using System.Threading;
 using System.Threading.Tasks;
 using Windows.Graphics;
 using Windows.Graphics.Capture;
@@ -27,9 +29,23 @@ public sealed class ScreenCaptureFrameSource : IScreenCaptureSource
    private GraphicsCaptureSession? _session;
    private SizeInt32 _poolSize;
    private bool _started;
-    private bool _framePending;
+    private int _convertInFlight;
    private DateTime _lastErrorLog = DateTime.MinValue;
    // Buffer recycling (take-11 spikes, 2026-09-04; slice 16, 2026-09-14): a fresh
    // ~8.3MB byte[] per DWM frame ≈ 500MB/s of LOH churn — the gen2 pauses it forced
    // surfaced as the "worst render 35-65ms" spikes that capped fps at ~42. The pool
    // is a reuse-distance ring: a buffer is only rewritten after ≥ redLine rents have
    // cycled since its last hand-out (FrameRingBuffer), so a frame a consumer still
    // holds — session.LatestFrame survives across conversions and the dispatcher
    // preview copy lags — can never be overwritten in place (the 1742 tear, a ring
    // slot rewritten under the consumer's read, handed the compositor one
    // new-top/old-bottom frame). Each hand-out still carries an Epoch so identity-keyed
    // consumers (the compositor's paste cache) cannot false-hit a recycled array.
    private readonly FrameRingBuffer _ring = new(8, redLine: 4);
    private long _epoch;
    private readonly MonotonicGate _publishGate = new();
    // The composition master frame (see ai.md "Resolution tiers"): the background
    // is an input layer, so we never hold a CPU frame bigger than the master.
    private const int MaxBackgroundWidth = 1920;
@@ -38,6 +54,28 @@ public sealed class ScreenCaptureFrameSource : IScreenCaptureSource
    // A failing conversion must not re-flood the log at frame rate.
    private static readonly TimeSpan ErrorLogThrottle = TimeSpan.FromSeconds(5);
    // Conversion cadence (slice 16, 2026-09-14; slice 17, 2026-09-14): the monitor
    // delivers at the 240Hz DWM cadence (~4.2ms) while slots are 16.6ms. A 10ms floor
    // between conversion starts keeps the open edge above the ~60 conversions/s the pump
    // can use. What actually bounded the desktop feed on takes 1742/1824 was the SERIAL
    // GPU→CPU readback (`CreateCopyFromSurfaceAsync` ≈ 40-50ms of the ~47ms conversion
    // on a 240Hz-HDR box shared with the encoder), capping captures at ~17-20/s.
    // Slice 17 overlaps up to MaxConcurrentConversions readbacks (pool sized to
    // accommodate in-flight frames) and publishes only monotonically newer frames
    // (MonotonicGate — a slow older completion must never overwrite a newer LatestFrame).
    private static readonly TimeSpan MinConvertInterval = TimeSpan.FromMilliseconds(10);
    private static readonly TimeSpan TelemetryInterval = TimeSpan.FromSeconds(2);
    private const int MaxConcurrentConversions = 3;
    private const int PoolBufferCount = 5;
    private DateTime _lastConvertAt = DateTime.MinValue;
    private DateTime _telemetryFrom = DateTime.UtcNow;
    private DateTime _lastTelemetry = DateTime.UtcNow;
    private long _skippedCadence;
    private long _skippedBusy;
    private long _conversions;
    private long _convertMsTotal;
    private long _convertMsMax;
    public string Key { get; }
    public event Action<VideoFrame>? FrameAvailable;
@@ -74,7 +112,7 @@ public sealed class ScreenCaptureFrameSource : IScreenCaptureSource
            var item = _item;
            var device = Direct3D11Helper.CreateDevice();
            var framePool = Direct3D11CaptureFramePool.CreateFreeThreaded(
-                device, DirectXPixelFormat.B8G8R8A8UIntNormalized, 2, item.Size);
+                device, DirectXPixelFormat.B8G8R8A8UIntNormalized, PoolBufferCount, item.Size);
            _poolSize = item.Size;
            var session = framePool.CreateCaptureSession(item);
            framePool.FrameArrived += OnFrameArrived;
@@ -91,7 +129,7 @@ public sealed class ScreenCaptureFrameSource : IScreenCaptureSource
        lock (_gate)
        {
            _started = false;
-            _framePending = false;
+            _convertInFlight = 0;
            if (_framePool != null)
                _framePool.FrameArrived -= OnFrameArrived;
            _session?.Dispose();
@@ -106,6 +144,7 @@ public sealed class ScreenCaptureFrameSource : IScreenCaptureSource
    {
        var frame = sender.TryGetNextFrame();
        if (frame == null) return;
        lock (_gate)
        {
            if (!_started)
@@ -113,33 +152,54 @@ public sealed class ScreenCaptureFrameSource : IScreenCaptureSource
                frame.Dispose();
                return;
            }
        }
-        if (frame.ContentSize.Width != _poolSize.Width || frame.ContentSize.Height != _poolSize.Height)
+            if (frame.ContentSize.Width != _poolSize.Width || frame.ContentSize.Height != _poolSize.Height)
-        {
+            {
-            sender.Recreate(Direct3D11Helper.CreateDevice(),
+                sender.Recreate(Direct3D11Helper.CreateDevice(),
-                DirectXPixelFormat.B8G8R8A8UIntNormalized, 2, frame.ContentSize);
+                    DirectXPixelFormat.B8G8R8A8UIntNormalized, PoolBufferCount, frame.ContentSize);
-            _poolSize = frame.ContentSize;
+                _poolSize = frame.ContentSize;
-        }
+            }
-        if (_framePending)
+            // Up to MaxConcurrentConversions readbacks in flight (slice 17), spaced by
-        {
+            // MinConvertInterval (slice 16): the 240Hz delivery otherwise queued one
-            frame.Dispose();
+            // conversion every ~4.2ms, and the serial ~47ms readback pinned the desktop
-            return;
+            // layer to ~17 updates/s on the 1824 take.
            if (_convertInFlight >= MaxConcurrentConversions)
            {
                _skippedBusy++;
                frame.Dispose();
                return;
            }
            var now = DateTime.UtcNow;
            if (now - _lastConvertAt < MinConvertInterval)
            {
                _skippedCadence++;
                frame.Dispose();
                return;
            }
            _lastConvertAt = now;
            _convertInFlight++;
        }
        _framePending = true;
        _ = ProcessFrameAsync(frame);
    }
    private async Task ProcessFrameAsync(Direct3D11CaptureFrame frame)
    {
        var sw = Stopwatch.StartNew();
        try
        {
            using (frame)
            using (var softwareBitmap = await SoftwareBitmap.CreateCopyFromSurfaceAsync(
                frame.Surface, BitmapAlphaMode.Ignore))
            {
-                FrameAvailable?.Invoke(CopyToVideoFrame(softwareBitmap));
+                // Monotonic sequencing across the overlapping conversions (slice 17): a
                // completed readback is published only if strictly newer than the last
                // one published — a slow older completion must never overwrite a newer
                // LatestFrame (that would be a time hole in the other direction).
                var epoch = Interlocked.Increment(ref _epoch);
                var videoFrame = CopyToVideoFrame(softwareBitmap, epoch);
                if (_publishGate.TryPublish(epoch))
                    FrameAvailable?.Invoke(videoFrame);
            }
        }
        catch (Exception ex)
@@ -153,11 +213,41 @@ public sealed class ScreenCaptureFrameSource : IScreenCaptureSource
        }
        finally
        {
-            _framePending = false;
+            lock (_gate)
            {
                EmitTelemetry(sw.ElapsedMilliseconds);
                _convertInFlight--;
            }
        }
    }
-    private static VideoFrame CopyToVideoFrame(SoftwareBitmap bitmap)
+    private void EmitTelemetry(long conversionMs)
    {
        _conversions++;
        _convertMsTotal += conversionMs;
        if (conversionMs > _convertMsMax) _convertMsMax = conversionMs;
        var now = DateTime.UtcNow;
        if (now - _lastTelemetry < TelemetryInterval) return;
        var span = now - _telemetryFrom;
        var perSecond = span.TotalSeconds > 0 ? _conversions / span.TotalSeconds : 0;
        AppLog.Write(
            $"ScreenCapture telemetry [{Key}]: {_conversions} frames in {span.TotalSeconds:F1}s " +
            $"({perSecond:F0}/s), conv avg {( _conversions == 0 ? 0 : _convertMsTotal / _conversions )}ms " +
            $"max {_convertMsMax}ms, skip busy {_skippedBusy} cadence {_skippedCadence}, " +
            $"ring allocs {_ring.ConsumeAllocations()}");
        _lastTelemetry = now;
        _telemetryFrom = now;
        _conversions = 0;
        _convertMsTotal = 0;
        _convertMsMax = 0;
        _skippedBusy = 0;
        _skippedCadence = 0;
    }
    private VideoFrame CopyToVideoFrame(SoftwareBitmap bitmap, long epoch)
    {
        var sw = bitmap.PixelWidth;
        var sh = bitmap.PixelHeight;
@@ -177,45 +267,61 @@ public sealed class ScreenCaptureFrameSource : IScreenCaptureSource
            var scale = Math.Min(MaxBackgroundWidth / (double)sw, MaxBackgroundHeight / (double)sh);
            var dw = Math.Max(1, (int)(sw * scale));
            var dh = Math.Max(1, (int)(sh * scale));
-            return new VideoFrame(dw, dh, DownscaleBgra(data, sw, sh, srcStride, dw, dh));
+            // DWM delivers an opaque surface (alpha 255); bilinear keeps it 255.
            var scaled = _ring.Rent(dw * dh * 4);
            return new VideoFrame(dw, dh, DownscaleBgra(data, sw, sh, srcStride, dw, dh, scaled))
                { IsOpaque = true, Epoch = epoch };
        }
-        var pixels = new byte[count];
+        var pixels = _ring.Rent(count);
        Marshal.Copy(data, pixels, 0, pixels.Length);
-        return new VideoFrame(sw, sh, pixels);
+        return new VideoFrame(sw, sh, pixels) { IsOpaque = true, Epoch = epoch };
    }
-    // Bilinear downscale to the master frame. Reads each source row pair through
+    // Integer 8.8 fixed-point bilinear downscale to the master frame (slice 16,
-    // Marshal.Copy (no unsafe), writing tightly packed BGRA output.
+    // 2026-09-14: the two-stage math from SceneCompositor.Bilinear — the same "shift
-    private static byte[] DownscaleBgra(IntPtr src, int sw, int sh, int srcStride, int dw, int dh)
+    // only at the end" rule from MyMistakes item on fixed-point blending). The previous
    // double-per-pixel version ran ~30-45ms per 2.5K→1080p frame on a quiet desktop
    // and the 1742 take's stall measured ~150ms/frame under load (90%-frozen desktop,
    // ~6 fresh frames/s); integer math keeps the same bilinear result within ±1 while
    // dropping the cost to the row-pair Marshal.Copy. Rows are read once per source
    // row pair through Marshal.Copy (no unsafe), writing tightly packed BGRA output.
    private byte[] DownscaleBgra(IntPtr src, int sw, int sh, int srcStride, int dw, int dh, byte[] dst)
    {
        // Row scratch is per-conversion (overlapping conversions since slice 17 each
        // bring their own — two 10KB arrays, no shared state). Size: a 2560-wide row
        // pair, the largest the monitor path delivers before the downscale.
        var row0 = new byte[srcStride];
        var row1 = new byte[srcStride];
        var dst = new byte[dw * dh * 4];
        var xs = sw / (double)dw;
        var ys = sh / (double)dh;
        for (var y = 0; y < dh; y++)
        {
-            var sy = Math.Min(sh - 1, (int)(y * ys));
+            var sy8 = (int)((long)y * sh * 256 / dh);
            var sy = sy8 >> 8;
            var sy1 = Math.Min(sh - 1, sy + 1);
-            var fy = (y * ys) - sy;
+            var fy8 = sy8 & 255;
            var fyInv = 256 - fy8;
            Marshal.Copy(IntPtr.Add(src, sy * srcStride), row0, 0, srcStride);
            Marshal.Copy(IntPtr.Add(src, sy1 * srcStride), row1, 0, srcStride);
            var dRow = y * dw * 4;
            for (var x = 0; x < dw; x++)
            {
-                var sx = Math.Min(sw - 1, (int)(x * xs));
+                var sx8 = (int)((long)x * sw * 256 / dw);
                var sx = Math.Min(sw - 1, sx8 >> 8);
                var sx1 = Math.Min(sw - 1, sx + 1);
-                var fx = (x * xs) - sx;
+                var fx8 = sx8 & 255;
-                for (var c = 0; c < 4; c++)
+                var fxInv = 256 - fx8;
                var i0 = sx * 4;
                var i1 = sx1 * 4;
                var j = dRow + x * 4;
                for (var c = 0; c < 4; c++, i0++, i1++, j++)
                {
-                    var i0 = sx * 4 + c;
+                    // Two-stage in one 16.8 scale: top/bot ≤ 65280, ×256 + round ≤ 33.5M — int-safe.
-                    var i1 = sx1 * 4 + c;
+                    var top = row0[i0] * fxInv + row0[i1] * fx8;
-                    var top = row0[i0] + (row0[i1] - row0[i0]) * fx;
+                    var bot = row1[i0] * fxInv + row1[i1] * fx8;
-                    var bottom = row1[i0] + (row1[i1] - row1[i0]) * fx;
+                    dst[j] = (byte)((top * fyInv + bot * fy8 + 32768) >> 16);
                    dst[dRow + x * 4 + c] = (byte)(top + (bottom - top) * fy);
                }
            }
        }
@@ -38,7 +38,11 @@ public sealed class ScreenCaptureSourceFactory
        if (key.StartsWith("window:", StringComparison.OrdinalIgnoreCase))
        {
-            var hexText = key.AsSpan("window:".Length);
+            // Keys are written as "window:0x<Hwnd:X>" (CaptureInterop/WindowInfo),
            // but NumberStyles.HexNumber does not accept the "0x" prefix — strip it.
            var hexText = key.AsSpan("window:".Length).TrimStart();
            if (hexText.Length >= 2 && hexText[0] == '0' && (hexText[1] == 'x' || hexText[1] == 'X'))
                hexText = hexText[2..];
            if (long.TryParse(hexText, NumberStyles.HexNumber, CultureInfo.InvariantCulture, out var hwnd))
                return ScreenCaptureFrameSource.CreateForWindow(new IntPtr(hwnd));
            return null;
@@ -0,0 +1,237 @@
 using System;
 using System.Threading.Tasks;
 using System.Windows.Input;
 using ytLive.Helpers;
 using ytLive.Models;
 namespace ytLive.Services;
 /// <summary>
 /// TASK 41 — the Test Stream pull-out (the "TEST" tab at the bottom of the Live
 /// screen's right rail). Drives a private test broadcast's chat tooling:
 /// Mock Chat Input sends a REAL liveChat/messages.insert (round-tripping through
 /// the normal ~2s poll and the live overlay path), and the simulated-event buttons
 /// inject synthetic member / SuperChat / subscriber rows through the exact
 /// MessageReceived seam the real poll uses — local-only, never sent to YouTube
 /// (the insert API only creates text). The broadcast itself runs through the real
 /// private go-live pipeline; this VM only owns the dock.
 /// </summary>
 public sealed class TestSessionViewModel : ViewModelBase
 {
    private readonly YouTubeStreamService _stream;
    private readonly YouTubeChatService _chat;
    private readonly Action? _onEndStream;
    private bool _isDrawerOpen;
    private bool _isTestSession;
    private string? _broadcastId;
    private string? _liveChatId;
    private string _sendMessageText = string.Empty;
    private bool _isSending;
    private string? _lastEventText;
    private int _eventCounter;
    /// <summary>Fake viewer names for simulated events — several backs make the
    /// rows look like a real muted room.</summary>
    private static readonly string[] SimulatedViewers = { "PixelPasta", "NightskyNick", "LunaGlow", "CactusFox" };
    public TestSessionViewModel(
        YouTubeStreamService stream,
        YouTubeChatService chat,
        Action? onEndStream = null)
    {
        _stream = stream;
        _chat = chat;
        _onEndStream = onEndStream;
        SendTestMessageCommand = new RelayCommand(_ => _ = SendTestMessageAsync(), _ => CanSendTestMessage);
        SimulateSubscriberCommand = new RelayCommand(_ => Simulate(SimulatedSubscriber()));
        SimulateMemberCommand = new RelayCommand(_ => Simulate(SimulatedMember()));
        SimulateSuperChatCommand = new RelayCommand(_ => Simulate(SimulatedSuperChat()));
        EndTestCommand = new RelayCommand(_ => _onEndStream?.Invoke());
        ToggleDrawerCommand = new RelayCommand(_ => IsDrawerOpen = !IsDrawerOpen);
        CloseDrawerCommand = new RelayCommand(_ => IsDrawerOpen = false);
    }
    public ICommand SendTestMessageCommand { get; }
    public RelayCommand SimulateSubscriberCommand { get; }
    public RelayCommand SimulateMemberCommand { get; }
    public RelayCommand SimulateSuperChatCommand { get; }
    public RelayCommand EndTestCommand { get; }
    public RelayCommand ToggleDrawerCommand { get; }
    public RelayCommand CloseDrawerCommand { get; }
    public bool IsDrawerOpen
    {
        get => _isDrawerOpen;
        set => SetProperty(ref _isDrawerOpen, value);
    }
    /// <summary>Whether a test broadcast is currently live (ended by BeginTest /
    /// EndTestSilently; EndTestCommand asks the app to stop, which routes back here).</summary>
    public bool IsTestSession
    {
        get => _isTestSession;
        private set
        {
            if (SetProperty(ref _isTestSession, value))
            {
                OnPropertyChanged(nameof(SessionCaption));
                OnPropertyChanged(nameof(ChatIdLine));
                OnPropertyChanged(nameof(CanSendTestMessage));
            }
        }
    }
    public string? BroadcastId => _broadcastId;
    public string ChatIdLine => _liveChatId == null ? "liveChatId: —" : $"liveChatId: {_liveChatId}";
    public string SessionCaption => IsTestSession
        ? "Test stream is live — private to you, zero notifications, real chat."
        : "No test in progress — hit the Test button in the top bar to start a private broadcast and check your chat overlay.";
    public string SendMessageText
    {
        get => _sendMessageText;
        set
        {
            if (SetProperty(ref _sendMessageText, value))
                OnPropertyChanged(nameof(CanSendTestMessage));
        }
    }
    public bool IsSending
    {
        get => _isSending;
        private set
        {
            if (SetProperty(ref _isSending, value))
                OnPropertyChanged(nameof(CanSendTestMessage));
        }
    }
    public bool CanSendTestMessage => IsTestSession && !IsSending && _liveChatId != null
        && !string.IsNullOrWhiteSpace(SendMessageText);
    /// <summary>Feedback line for the last send / simulated event (null = nothing yet).</summary>
    public string? LastEventText
    {
        get => _lastEventText;
        private set => SetProperty(ref _lastEventText, value);
    }
    /// <summary>Called once by MainViewModel when the test broadcast is live and its
    /// liveChatId resolved — opens the dock so the chat tools are immediately usable.</summary>
    public void BeginTest(string broadcastId, string? liveChatId)
    {
        _broadcastId = broadcastId;
        _liveChatId = string.IsNullOrWhiteSpace(liveChatId) ? null : liveChatId;
        SendMessageText = string.Empty;
        LastEventText = _liveChatId == null
            ? "Chat polling couldn't start — Mock Chat Input is disabled."
            : null;
        IsTestSession = true;
        IsDrawerOpen = true;
    }
    /// <summary>Called by MainViewModel's stop path when the broadcast ends — the
    /// dock forgets the ended session (idempotent).</summary>
    public void EndTestSilently()
    {
        _broadcastId = null;
        _liveChatId = null;
        IsTestSession = false;
        IsSending = false;
    }
    /// <summary>Mock Chat Input: real liveChat/messages.insert. The inserted text
    /// arrives through the normal poll and renders via the live overlay path — the
    /// whole point is that the round-trip is the real one.</summary>
    public async Task SendTestMessageAsync()
    {
        if (!CanSendTestMessage || _liveChatId == null) return;
        var text = SendMessageText.Trim();
        IsSending = true;
        SendMessageText = string.Empty;
        LastEventText = null;
        try
        {
            var error = await _stream.InsertChatMessageAsync(_liveChatId, text);
            LastEventText = error == null
                ? $"Sent — “{text}” should appear on the chat overlay within a couple of seconds."
                : $"Couldn't send: {error}";
        }
        catch (Exception ex)
        {
            AppLog.Write($"Test chat message send failed: {ex.Message}");
            LastEventText = "Couldn't send that message — try again.";
        }
        finally
        {
            IsSending = false;
        }
    }
    private void Simulate(ChatMessage message)
    {
        if (!IsTestSession) return;
        _chat.InjectSimulatedMessage(message);
        _eventCounter++;
        LastEventText = $"Fired #{_eventCounter}: {Describe(message)} — renders on any visible chat overlay.";
        AppLog.Write($"Test chat simulation {_eventCounter} injected");
    }
    /// <summary>Subscriptions aren't chat events on YouTube, so a "subscriber" row
    /// is a plain text-shaped message carrying the count — honest: the chat overlay
    /// shows it as a regular row, which is exactly what a sub looks like in chat.
    /// It carries <see cref="ChatEventKind.None"/> on purpose: no alert animation
    /// fires for free subs — the chat mention is the announcement (creator ruling).</summary>
    private ChatMessage SimulatedSubscriber()
    {
        var author = NextViewer();
        return NewSimulated(author, "New subscriber — welcome to the herd! 🦙 (simulated subscribe)");
    }
    private ChatMessage SimulatedMember()
    {
        var author = NextViewer();
        var message = NewSimulated(author, $"🎉 {author} became a member!");
        message.IsMember = true;
        message.MembershipLevel = "New member";
        message.Kind = ChatEventKind.NewMember;
        return message;
    }
    private ChatMessage SimulatedSuperChat()
    {
        var author = NextViewer();
        var message = NewSimulated(author, "Keep the streams flowing, llama power 🦙");
        message.IsSuperChat = true;
        message.SuperChatAmount = 5.00;
        message.SuperChatCurrency = "$";
        message.SuperChatDisplayString = "$5.00";
        message.Kind = ChatEventKind.SuperChat;
        return message;
    }
    private ChatMessage NewSimulated(string author, string text)
    {
        return new ChatMessage
        {
            AuthorName = author,
            Message = text,
            Timestamp = DateTime.Now,
            IsSimulated = true,
        };
    }
    private string NextViewer() => SimulatedViewers[_eventCounter % SimulatedViewers.Length];
    private static string Describe(ChatMessage m)
    {
        if (m.IsSuperChat) return $"{m.AuthorName} pledged {m.SuperChatCurrency}{m.SuperChatAmount:0.00} in a Super Chat";
        if (m.IsMember) return $"{m.AuthorName} just became a member ({m.MembershipLevel})";
        return $"{m.AuthorName} subscribed";
    }
 }
@@ -13,6 +13,43 @@ public sealed class VideoFrame
    public byte[] BgraPixels { get; }
    public int Stride => Width * 4;
    /// <summary>Producer frame epoch — a monotonically increasing number stamped by
    /// sources that RECYCLE their pixel buffers (the screen-capture ring, take-11 spike
    /// fix). Consumers that key caches on buffer identity (the compositor's paste cache)
    /// MUST include it, or a recycled array false-hits with stale content. Producers
    /// that hand out fresh arrays per frame leave it 0 — identity alone is then enough.</summary>
    public long Epoch { get; init; }
    /// <summary>Producer contract: every alpha byte in <see cref="BgraPixels"/> is 255
    /// (DWM capture surfaces and MediaCapture video carry no alpha — the OS fills 255).
    /// Lets the compositor take a straight-copy fast path for a full-canvas opaque
    /// layer instead of 2M per-pixel blends. NEVER set it for paths whose pixels can
    /// be transparent (static art, web overlays, chat, the social-bar strip).</summary>
    public bool IsOpaque { get; init; }
    /// <summary>WebSource crop metadata: the alpha bounding box of the widget content
    /// within the full canvas (X/Y/W/H in pixels). When set, the compositor uses these
    /// bounds for Fill-style scaling (stretch to cover, no aspect preservation) instead of
    /// UniformToFill. The transparent margins of the full canvas are preserved so they
    /// reveal layers beneath — the crop defines the actual content region.</summary>
    public (int X, int Y, int W, int H)? CropBounds { get; init; }
    /// <summary>Where a SMALLER-than-canvas overlay composites, in master pixels
    /// (creator ruling 2026-09-26: the alert ticker draws INSIDE the Stream Alerts video
    /// box, not as a full-width strip pinned to the top edge). <c>null</c> — the default
    /// — means the canvas origin, which is what every full-canvas overlay wants.
    /// <para>This is deliberately NOT a full-canvas frame: at 30–60fps a 1920×1080
    /// overlay is 8.3MB of large-object-heap garbage per tick, and a 10s alert would
    /// churn ~2.5GB. A box-sized strip is ~370KB, so the position travels on the frame
    /// instead of in a 1920-wide transparent margin.</para></summary>
    public (int X, int Y)? Placement { get; init; }
    /// <summary>Composite origin X: <see cref="Placement"/> if set, else 0.</summary>
    public int OriginX => Placement?.X ?? 0;
    /// <summary>Composite origin Y: <see cref="Placement"/> if set, else 0.</summary>
    public int OriginY => Placement?.Y ?? 0;
    public VideoFrame(int width, int height, byte[] bgraPixels)
    {
        Width = width;
@@ -0,0 +1,232 @@
 using System;
 using System.Runtime.InteropServices;
 using System.Runtime.InteropServices.WindowsRuntime;
 using System.Threading.Tasks;
 using Windows.Graphics;
 using Windows.Graphics.Capture;
 using Windows.Graphics.DirectX;
 using Windows.Graphics.DirectX.Direct3D11;
 using Windows.Graphics.Imaging;
 using ytLive.Helpers;
 namespace ytLive.Services;
 /// <summary>
 /// The frame-driven web capture for one widget: a GraphicsCaptureItem backed by
 /// the widget's Windows.UI.Composition visual (see WebView2Manager). Owns the
 /// item, a free-threaded Direct3D11CaptureFramePool and the capture session;
 /// frames arrive in step with Chromium's own presentation (~60Hz on a real
 /// animation), replacing the old CapturePreviewAsync PNG poll whose ~35-165ms
 /// encode cost capped the recording at ~10Hz and the preview at ~5fps.
 ///
 /// The capture surface holds a REAL alpha channel (the controller renders onto
 /// a transparent composition visual), so the GPU→CPU copy uses
 /// <see cref="BitmapAlphaMode.Straight"/> and the frame is
 /// <see cref="VideoFrame.IsOpaque"/> = false — the compositor's straight-alpha
 /// blend math ("web layer transparency", 2026-09-13) requires the readback to
 /// keep premultiplication OFF. Unlike the screen source there is no master-size
 /// downscale: the controller renders at the RAW 1920×1080 master canvas, so the
 /// CPU never holds a larger frame.
 ///
 /// Per-frame the alpha bounding box of the widget (<see cref="FindContentBounds"/>)
 /// is measured on this capture worker thread and stamped onto the frame as
 /// <see cref="VideoFrame.CropBounds"/> — same alpha-bbox contract as the old
 /// PNG path, but off the UI thread (a 2M-pixel scan per frame there is exactly
 /// the cost this redesign exists to remove).
 /// </summary>
 public sealed class WebCaptureFrameSource : IScreenCaptureSource
 {
    private readonly object _gate = new();
    private GraphicsCaptureItem _item;
    private Direct3D11CaptureFramePool? _framePool;
    private GraphicsCaptureSession? _session;
    private SizeInt32 _poolSize;
    private bool _started;
    private bool _framePending;
    private DateTime _lastErrorLog = DateTime.MinValue;
    // Buffer recycling: identical to the screen source's ring+Epoch contract
    // (see ScreenCaptureFrameSource) — the compositor's paste cache is keyed on
    // array identity, so recycled buffers must carry a monotonic Epoch or a
    // reused array false-hits with stale content.
    private readonly byte[]?[] _frameRing = new byte[8][];
    private int _ringNext;
    private long _epoch;
    private static readonly TimeSpan ErrorLogThrottle = TimeSpan.FromSeconds(5);
    public string Key { get; }
    public event Action<VideoFrame>? FrameAvailable;
    internal WebCaptureFrameSource(string key, GraphicsCaptureItem item)
    {
        Key = key;
        _item = item;
    }
    /// <summary>Wraps an item created from a composition visual by the web manager.</summary>
    public static WebCaptureFrameSource CreateForVisual(string key, GraphicsCaptureItem item)
        => new(key, item);
    public Task StartAsync()
    {
        lock (_gate)
        {
            if (_started) return Task.CompletedTask;
            var item = _item;
            var device = Direct3D11Helper.CreateDevice();
            var framePool = Direct3D11CaptureFramePool.CreateFreeThreaded(
                device, DirectXPixelFormat.B8G8R8A8UIntNormalized, 2, item.Size);
            _poolSize = item.Size;
            var session = framePool.CreateCaptureSession(item);
            framePool.FrameArrived += OnFrameArrived;
            session.StartCapture();
            _framePool = framePool;
            _session = session;
            _started = true;
        }
        return Task.CompletedTask;
    }
    public Task StopAsync()
    {
        lock (_gate)
        {
            _started = false;
            _framePending = false;
            if (_framePool != null)
                _framePool.FrameArrived -= OnFrameArrived;
            _session?.Dispose();
            _session = null;
            _framePool?.Dispose();
            _framePool = null;
        }
        return Task.CompletedTask;
    }
    private void OnFrameArrived(Direct3D11CaptureFramePool sender, object args)
    {
        var frame = sender.TryGetNextFrame();
        if (frame == null) return;
        lock (_gate)
        {
            if (!_started)
            {
                frame.Dispose();
                return;
            }
        }
        if (frame.ContentSize.Width != _poolSize.Width || frame.ContentSize.Height != _poolSize.Height)
        {
            sender.Recreate(Direct3D11Helper.CreateDevice(),
                DirectXPixelFormat.B8G8R8A8UIntNormalized, 2, frame.ContentSize);
            _poolSize = frame.ContentSize;
        }
        if (_framePending)
        {
            frame.Dispose();
            return;
        }
        _framePending = true;
        _ = ProcessFrameAsync(frame);
    }
    private async Task ProcessFrameAsync(Direct3D11CaptureFrame frame)
    {
        try
        {
            using (frame)
            using (var softwareBitmap = await SoftwareBitmap.CreateCopyFromSurfaceAsync(
                frame.Surface, BitmapAlphaMode.Straight))
            {
                FrameAvailable?.Invoke(CopyToVideoFrame(softwareBitmap));
            }
        }
        catch (Exception ex)
        {
            var now = DateTime.UtcNow;
            if (now - _lastErrorLog >= ErrorLogThrottle)
            {
                _lastErrorLog = now;
                AppLog.Write($"WebCaptureFrameSource: frame conversion failed: {ex.Message}");
            }
        }
        finally
        {
            _framePending = false;
        }
    }
    private byte[] RentRingBuffer(int size)
    {
        for (var tries = 0; tries < _frameRing.Length; tries++)
        {
            var idx = (_ringNext + tries) % _frameRing.Length;
            var buf = _frameRing[idx];
            if (buf is { Length: var len } && len == size)
            {
                _ringNext = (idx + 1) % _frameRing.Length;
                return buf;
            }
        }
        var slot = _ringNext;
        _ringNext = (slot + 1) % _frameRing.Length;
        var fresh = new byte[size];
        _frameRing[slot] = fresh;
        return fresh;
    }
    private VideoFrame CopyToVideoFrame(SoftwareBitmap bitmap)
    {
        var sw = bitmap.PixelWidth;
        var sh = bitmap.PixelHeight;
        using var buffer = bitmap.LockBuffer(BitmapBufferAccessMode.Read);
        using var reference = buffer.CreateReference();
        if (!WindowsRuntimeMarshal.TryGetDataUnsafe(reference, out var data, out var capacity))
            throw new InvalidOperationException("Could not access the frame buffer.");
        var srcStride = sw * 4;
        var count = (int)Math.Min(capacity, (uint)(sh * srcStride));
        var pixels = RentRingBuffer(count);
        Marshal.Copy(data, pixels, 0, pixels.Length);
        var (cropX, cropY, cropW, cropH) = FindContentBounds(pixels, sw, sh, srcStride);
        return new VideoFrame(sw, sh, pixels)
        {
            IsOpaque = false,
            Epoch = ++_epoch,
            CropBounds = (cropX, cropY, cropW, cropH),
        };
    }
    // The widget's extent is measured from the captured frame itself: the
    // bounding box of non-transparent pixels (the background is injected
    // transparent, so the alpha channel IS the widget). Immune to DOM timing
    // (fonts/images/animations), needs no JS round-trip, and CANNOT break the
    // render: a widget that fills the canvas gets the full frame; a widget that
    // floats in transparent margin gets exactly its content box — used for the
    // preview bitmap / selection. The frame handed to the compositor is always
    // the FULL canvas, so the page's transparent margins keep revealing the
    // layers beneath (the "black square over webcam" was the crop fed to the
    // compositor: UniformToFill zoomed the opaque content box over the element).
    internal static (int X, int Y, int W, int H) FindContentBounds(byte[] pixels, int pixW, int pixH, int stride)
    {
        int minX = pixW, minY = pixH, maxX = -1, maxY = -1;
        for (var y = 0; y < pixH; y++)
        {
            var row = y * stride;
            for (var x = 0; x < pixW; x++)
            {
                if (pixels[row + x * 4 + 3] == 0) continue;
                if (x < minX) minX = x;
                if (x > maxX) maxX = x;
                if (y < minY) minY = y;
                if (y > maxY) maxY = y;
            }
        }
        if (maxX < minX || maxY < minY) return (0, 0, pixW, pixH);
        return (minX, minY, maxX - minX + 1, maxY - minY + 1);
    }
 }
@@ -1,86 +1,93 @@
 using System;
 using System.Collections.Generic;
 using System.Drawing;
 using System.IO;
-using System.Text.Json;
+using System.Runtime.InteropServices;
 using System.Threading.Tasks;
 using System.Windows;
 using System.Windows.Controls;
 using System.Windows.Media;
 using System.Windows.Media.Imaging;
 using System.Windows.Threading;
 using Microsoft.Web.WebView2.Core;
-using Microsoft.Web.WebView2.Wpf;
+using Windows.Graphics.Capture;
 using Windows.System;
 using Windows.UI.Composition;
 using ytLive.Helpers;
 using ytLive.Models;
 namespace ytLive.Services;
 /// <summary>
 /// Owns the composition-based web sources (one per widget). A session renders
 /// its widget through a <see cref="CoreWebView2CompositionController"/> whose
 /// visual tree lives off-screen on the WPF UI thread (OBS web-source model:
 /// the page renders at the MASTER CANVAS size 1920×1080, stable, never tracked);
 /// the controller's root visual is captured by a <see cref="WebCaptureFrameSource"/>
 /// at Chromium's own presentation cadence. The preview is crop-copied to a shared
 /// WriteableBitmap on the UI thread (dispatcher-coalesced latest-wins, mirror of
 /// ScreenCaptureManager); the FramePump reads <see cref="GetLatestFrame"/>.
 ///
 /// The composition stack needs a DispatcherQueue on this thread (CsWinRT does not
 /// project <c>CreateOnCurrentThread</c> on the 19041 SDK — only the dedicated
 /// variant — so it is installed via a CoreMessaging P/Invoke, the documented
 /// fallback the WebView2CompositionControl / webview_windows embedders use).
 /// Everything composition-side therefore runs on the WPF UI thread; only the
 /// frame conversion and alpha-bbox scan run on the capture worker.
 ///
 /// Seam: an internal <c>Func&lt;string, IScreenCaptureSource&gt;</c> source
 /// factory substitutes the whole WebView2+item creation in tests — the manager
 /// then owns the session/coalesce/crop/preview plumbing exactly as in production.
 /// </summary>
 public sealed class WebView2Manager : IDisposable
 {
    private readonly Panel _hostPanel;
    private readonly Dispatcher _dispatcher;
    private readonly Func<string, IScreenCaptureSource>? _sessionSourceFactory;
    private readonly Dictionary<string, WebSourceSession> _sessions = new();
    private Task<CoreWebView2Environment>? _environmentTask;
    private DispatcherQueueController? _dispatcherQueueController;
    private Windows.UI.Composition.Compositor? _compositor;
    public event Action<string, WriteableBitmap>? PreviewBitmapChanged;
    private sealed class WebSourceSession
    {
-        public required WebView2 Control { get; init; }
+        public required string Key { get; init; }
-        public required DispatcherTimer CaptureTimer { get; init; }
+        public CoreWebView2? Web;
        public CoreWebView2CompositionController? Controller;
        public IScreenCaptureSource? Source;
        public Action<VideoFrame>? FrameHandler;
        public VideoFrame? LatestFrame;
        public WriteableBitmap? PreviewBitmap;
        // Buffer reuse (2026-09-04 lesson): the preview crop copy reuses one
        // scratch array while the widget's extent holds — no per-frame LOH mint.
        public byte[]? CropScratch;
        public bool Disposed;
        public bool Initialized;
        public bool FramePending;
        public bool FirstCaptureLogged;
        public int WidgetLogsRemaining;
    }
-    public WebView2Manager(Panel hostPanel, Dispatcher dispatcher)
+    public WebView2Manager(Dispatcher dispatcher)
        : this(dispatcher, null)
    {
    }
    /// <summary>Test seam: the source factory replaces WebView2+composition
    /// creation, so the session/coalesce/crop/preview plumbing is testable
    /// without the runtime.</summary>
    internal WebView2Manager(Dispatcher dispatcher, Func<string, IScreenCaptureSource>? sessionSourceFactory)
    {
        _hostPanel = hostPanel;
        _dispatcher = dispatcher;
        _sessionSourceFactory = sessionSourceFactory;
    }
    public void Register(Source source)
    {
        if (_sessions.ContainsKey(source.Id)) return;
-
+        _sessions[source.Id] = new WebSourceSession { Key = source.Id };
-        // OBS model: the page renders at the MASTER CANVAS size (1920×1080),
+        _ = InitializeAsync(source, _sessions[source.Id]);
        // stable, never tracked. Full-bleed widgets (designed for the canvas)
        // render fully instead of being clipped to a small box-sized viewport;
        // dragging the box never reflows the page. The capture is tightly
        // cropped to the widget's ALPHA bounding box (FindContentBounds) and
        // the display (Stretch=Fill) maps it flush under the box, anchored at
        // (0,0) — no DOM query, so no timing fragility; worst case is the
        // full frame, which is the confirmed-good rendering.
        var webView = new WebView2
        {
            Width = 1920,
            Height = 1080,
            DefaultBackgroundColor = System.Drawing.Color.Transparent,
            Visibility = System.Windows.Visibility.Visible,
        };
        Canvas.SetLeft(webView, -5000);
        Canvas.SetTop(webView, -5000);
        _hostPanel.Children.Add(webView);
        var timer = new DispatcherTimer
        {
            Interval = TimeSpan.FromMilliseconds(100),
        };
        var session = new WebSourceSession
        {
            Control = webView,
            CaptureTimer = timer,
        };
        _sessions[source.Id] = session;
        timer.Tick += (_, _) =>
        {
            if (!session.Disposed && session.Initialized)
                _ = CaptureFrame(source.Id);
        };
        _ = InitializeAsync(source, session);
    }
    public void Unregister(string sourceId) => RemoveSession(sourceId);
@@ -93,7 +100,7 @@ public sealed class WebView2Manager : IDisposable
        if (string.IsNullOrEmpty(source.WebUri))
        {
            session.LatestFrame = null;
-            session.Control.CoreWebView2?.NavigateToString(
+            session.Web?.NavigateToString(
                "<html><body style='background:transparent;margin:0'></body></html>");
            return;
        }
@@ -106,42 +113,116 @@ public sealed class WebView2Manager : IDisposable
        return _sessions.TryGetValue(sourceId, out var session) ? session.LatestFrame : null;
    }
    // Injected BEFORE the document is parsed (AddScriptToExecuteOnDocumentCreatedAsync) so
    // the widget page's own CSS/scripts cannot repaint html/body opaque — the reason the
    // late NavigationStarting/NavigationCompleted ExecuteScriptAsync injection lost the
    // fight (page styles ran first). A transparent capture REQUIRES the transparency in
    // place before the page paints, on the composition surface too.
    //
    // The OLD inline `element.style.background='transparent'` form lost to any page CSS:
    // a widget that paints a background-COLOR on a container (or html/body with stronger
    // specificity) after connect re-opaques the capture → the "black opaque box" in the
    // recording while the early frames were transparent. This is a solved problem in the
    // overlay ecosystem — OBS browser sources use a Custom CSS override and the decade-
    // validated formula for arbitrary pages is a `!important` background-color wipe
    // (OBS Forums 2016 "body { background-color: rgba(0,0,0,0) !important }",
    // https://obsproject.com/forum/threads/translucent-transparent-browser-source.59549/,
    // and the div-level variant for stubborn widgets, woahtech.com OBS custom-CSS guide).
    // A `<style>` node injected before parse, with `!important`, outranks every page rule
    // (only an author !important beats a later document-order !important; ours runs first).
    // Only background-COLOR was wiped at first — the 15:34 take showed the widget's own
    // full-canvas backdrop surviving as the box's black void: that paint is a CSS
    // background-IMAGE (gradient/backdrop), and the OBS fix for the same symptom is
    // `background: none !important` / background-image none, not color alone
    // (obsproject/obs-studio#6659 — "set the CSS for html and body to background: none
    // !important"). Wipe background-image too; HTML overlay art (the widget's content) is
    // <img>/DOM/CSS shapes and survives — only container decorations are removed, which is
    // OBS-browser-source semantics for a transparent overlay.
    internal const string TransparentBackgroundScript =
        "(function(){" +
        "if(document.getElementById('ytl-transparent-bg'))return;" +
        "var s=document.createElement('style');" +
        "s.id='ytl-transparent-bg';" +
        "s.appendChild(document.createTextNode(" +
        "'html,body{background-color:transparent!important;background-image:none!important;margin:0!important;overflow:hidden!important;}'" +
        "'html,body,html *{background-color:transparent!important;background-image:none!important;}'" +
        "));" +
        "(document.head||document.documentElement).appendChild(s);" +
        "})();";
    private async Task InitializeAsync(Source source, WebSourceSession session)
    {
        try
        {
-            await session.Control.EnsureCoreWebView2Async();
+            IScreenCaptureSource sourceImpl;
-
+            if (_sessionSourceFactory != null)
            var cws = session.Control.CoreWebView2!;
            cws.NavigationStarting += (_, _) =>
            {
-                _ = cws.ExecuteScriptAsync(
+                // Test path: the factory hands over a fully-configured source; the
-                    "document.documentElement.style.background='transparent';" +
+                // branch has no awaits, so Register() completes the session inline.
-                    "document.documentElement.style.overflow='hidden';" +
+                sourceImpl = _sessionSourceFactory(source.Id);
-                    "document.body.style.background='transparent';" +
+            }
-                    "document.body.style.overflow='hidden';");
+            else
            };
            cws.NavigationCompleted += (_, _) =>
            {
-                _ = cws.ExecuteScriptAsync(
+                var controller = await CreateControllerAsync();
-                    "document.documentElement.style.background='transparent';" +
+                if (controller == null)
-                    "document.documentElement.style.overflow='hidden';" +
+                {
-                    "document.body.style.background='transparent';" +
+                    RemoveSession(source.Id);
-                    "document.body.style.overflow='hidden';");
+                    return;
-                _ = CaptureFrame(source.Id);
+                }
            };
                session.Controller = controller;
                session.Web = controller.CoreWebView2;
                if (session.Web == null)
                {
                    RemoveSession(source.Id);
                    return;
                }
                // Pre-page hook: runs after the global object exists but BEFORE the document
                // parses / any page script runs — must complete before navigating away from
                // about:blank for it to apply to the widget document.
                await session.Web.AddScriptToExecuteOnDocumentCreatedAsync(TransparentBackgroundScript);
                session.Web.NavigationStarting += (_, _) =>
                {
                    _ = session.Web?.ExecuteScriptAsync(TransparentBackgroundScript);
                };
                session.Web.NavigationCompleted += (_, e) =>
                {
                    _ = session.Web?.ExecuteScriptAsync(TransparentBackgroundScript);
                    if (e.IsSuccess && session.Web?.Source is { } src && src != "about:blank")
                    {
                        // Log-only diagnostic on the REAL widget document (a few post-paint
                        // frames so styles/backgrounds settle). The first-capture dump only
                        // ever saw about:blank; the old PNG widget dumps are gone with the
                        // PNG path — alpha stats now ride the frame-driven channel.
                        session.WidgetLogsRemaining = 3;
                        var rearm = session;
                        _ = Task.Run(async () =>
                        {
                            await Task.Delay(TimeSpan.FromSeconds(30));
                            if (!rearm.Disposed) rearm.WidgetLogsRemaining = 3;
                        });
                    }
                };
                session.Web.NavigateToString(
                    "<html><body style='background:transparent;margin:0'></body></html>");
                if (!string.IsNullOrEmpty(source.WebUri))
                    Navigate(source.WebUri, session);
                session.Initialized = true;
                sourceImpl = new WebCaptureFrameSource(source.Id, CreateCaptureItem(controller));
            }
            session.Source = sourceImpl;
            session.FrameHandler = frame => OnFrameAvailable(session, frame);
            sourceImpl.FrameAvailable += session.FrameHandler;
            await sourceImpl.StartAsync();
            session.Initialized = true;
            session.Control.CoreWebView2.NavigateToString(
                "<html><body style='background:transparent;margin:0'></body></html>");
            if (!string.IsNullOrEmpty(source.WebUri))
                Navigate(source.WebUri, session);
            session.CaptureTimer.Start();
        }
        catch (Exception ex)
        {
@@ -150,116 +231,246 @@ public sealed class WebView2Manager : IDisposable
        }
    }
    // The environment MUST exist before the controller is created — it's created once
    // and shared by every session (one browser process). These flags (the
    // Electron-class embedder answer to Chromium throttling hidden pages — the moment
    // the app window is unfocused or covered, rAF parks and timers clamp to ~1s) keep
    // the renderer at full rate: --disable-backgrounding-occluded-windows,
    // --disable-renderer-backgrounding, and disable the native-window occlusion
    // detector that marks the page hidden.
    private Task<CoreWebView2Environment> GetEnvironmentAsync()
    {
        if (_environmentTask != null) return _environmentTask;
        var options = new CoreWebView2EnvironmentOptions
        {
            AdditionalBrowserArguments =
                "--disable-backgrounding-occluded-windows --disable-renderer-backgrounding --disable-features=CalculateNativeWinOcclusion",
        };
        // Per-instance user data folder in DEBUG: Chromium locks it exclusively, so
        // without this the second dev instance of the same exe fails to start at all.
        // Release passes null and WebView2 uses its default.
        var userData = InstanceProfile.WebViewDataFolder;
        if (userData != null) Directory.CreateDirectory(userData);
        return _environmentTask = CoreWebView2Environment.CreateAsync(null, userData, options);
    }
    /// <summary>Creates the composition controller off-screen under the main
    /// window (the parent HWND is required, the visual never mounts a window
    /// target). Set up is copied from the WebView2CompositionControl /
    /// webview_windows embedders: raw-pixel bounds at the master canvas,
    /// fixed rasterization scale, transparent default background.</summary>
    private async Task<CoreWebView2CompositionController?> CreateControllerAsync()
    {
        var mainWindow = Application.Current?.MainWindow;
        var hwnd = mainWindow == null
            ? IntPtr.Zero
            : new System.Windows.Interop.WindowInteropHelper(mainWindow).Handle;
        if (hwnd == IntPtr.Zero)
        {
            AppLog.Write("WebView2Manager: main window handle unavailable — web source not created");
            return null;
        }
        var env = await GetEnvironmentAsync();
        if (_compositor == null) _compositor = CreateCompositorForCurrentThread();
        var controller = await env.CreateCoreWebView2CompositionControllerAsync(hwnd);
        controller.Bounds = new Rectangle(0, 0, 1920, 1080);
        controller.BoundsMode = CoreWebView2BoundsMode.UseRawPixels;
        controller.ShouldDetectMonitorScaleChanges = false;
        controller.RasterizationScale = 1.0;
        controller.IsVisible = true;
        controller.DefaultBackgroundColor = System.Drawing.Color.Transparent;
        return controller;
    }
    private void Navigate(string url, WebSourceSession session)
    {
-        try { session.Control.CoreWebView2?.Navigate(url); }
+        try { session.Web?.Navigate(url); }
        catch (Exception ex) { AppLog.Write($"WebView2Manager: navigate failed: {ex.Message}"); }
    }
-    // The widget's extent is measured from the captured frame itself: the
+    // The visual tree webview_windows wires (offscreen mode): a root container
-    // bounding box of non-transparent pixels (the background is injected
+    // visual sized to the master canvas (the captured subject — the Flutter
-    // transparent, so the alpha channel IS the widget). This is immune to
+    // plugin calls GraphicsCaptureItem.CreateFromVisual on this root), with the
-    // DOM timing (fonts/images/animations), needs no JS round-trip, and
+    // controller's root visual target set to a child that fills the root via
-    // CANNOT break rendering: if the widget fills the canvas the box equals
+    // RelativeSizeAdjustment. BoundsMode raw pixels + RasterizationScale 1.0 keep
-    // the full frame (identical to the confirmed-good uncropped display); if
+    // the capture at exactly 1920×1080 regardless of monitor scale.
-    // it floats in transparent margin, the crop maps it flush under the box.
+    private GraphicsCaptureItem CreateCaptureItem(CoreWebView2CompositionController controller)
    internal static (int X, int Y, int W, int H) FindContentBounds(byte[] pixels, int pixW, int pixH, int stride)
    {
-        int minX = pixW, minY = pixH, maxX = -1, maxY = -1;
+        var compositor = _compositor!;
-        for (var y = 0; y < pixH; y++)
+        var root = compositor.CreateContainerVisual();
-        {
+        root.Size = new System.Numerics.Vector2(1920f, 1080f);
-            var row = y * stride;
+        root.IsVisible = true;
-            for (var x = 0; x < pixW; x++)
+
-            {
+        var webViewVisual = compositor.CreateContainerVisual();
-                if (pixels[row + x * 4 + 3] == 0) continue;
+        webViewVisual.RelativeSizeAdjustment = new System.Numerics.Vector2(1f, 1f);
-                if (x < minX) minX = x;
+        root.Children.InsertAtTop(webViewVisual);
-                if (x > maxX) maxX = x;
+
-                if (y < minY) minY = y;
+        controller.RootVisualTarget = webViewVisual;
-                if (y > maxY) maxY = y;
+        return GraphicsCaptureItem.CreateFromVisual(root);
            }
        }
        if (maxX < minX || maxY < minY) return (0, 0, pixW, pixH);
        return (minX, minY, maxX - minX + 1, maxY - minY + 1);
    }
-    private async Task CaptureFrame(string sourceId)
+    // CsWinRT does not project DispatcherQueueController.CreateOnCurrentThread
    // on the 19041 SDK (only CreateOnDedicatedThread [CS0117, verified by probe]);
    // the documented fallback — "how to create a DispatcherQueue on the current
    // thread" (learn.microsoft.com CoreMessaging docs) — is CreateDispatcherQueueController
    // from CoreMessaging.dll, wrapped via FromAbi (the CaptureInterop pattern). One
    // per UI thread, then new Compositor() (which requires the DQ) works here.
    private Windows.UI.Composition.Compositor CreateCompositorForCurrentThread()
    {
-        if (!_sessions.TryGetValue(sourceId, out var session) || session.Disposed) return;
+        var options = new DispatcherQueueOptions
        try
        {
-            var webView = session.Control;
+            DwSize = Marshal.SizeOf<DispatcherQueueOptions>(),
-            if (webView.CoreWebView2 == null) return;
+            ThreadType = 2,    // DQTYPE_THREAD_CURRENT
            ApartmentType = 2, // DQTAT_COM_STA — the WPF UI thread is STA
        };
        var hr = CreateDispatcherQueueController(options, out var controllerPtr);
        if (hr != 0)
            throw Marshal.GetExceptionForHR(hr)!;
        _dispatcherQueueController = DispatcherQueueController.FromAbi(controllerPtr);
        return new Windows.UI.Composition.Compositor();
    }
-            using var ms = new MemoryStream();
+    [StructLayout(LayoutKind.Sequential)]
-            await webView.CoreWebView2.CapturePreviewAsync(
+    private struct DispatcherQueueOptions
-                CoreWebView2CapturePreviewImageFormat.Png, ms);
+    {
        public int DwSize;
        public int ThreadType;
        public int ApartmentType;
    }
-            ms.Position = 0;
+    [DllImport("CoreMessaging.dll")]
    private static extern int CreateDispatcherQueueController(
        DispatcherQueueOptions options, out IntPtr dispatcherQueueController);
-            var bitmap = new BitmapImage();
+    private void OnFrameAvailable(WebSourceSession session, VideoFrame frame)
-            bitmap.BeginInit();
+    {
-            bitmap.StreamSource = ms;
+        if (session.Disposed) return;
-            bitmap.CacheOption = BitmapCacheOption.OnLoad;
+        session.LatestFrame = frame;
            bitmap.EndInit();
            bitmap.Freeze();
-            var formatted = new FormatConvertedBitmap(bitmap,
+        if (_dispatcher.CheckAccess())
-                PixelFormats.Bgra32, null, 0);
+        {
            UpdatePreview(session);
            return;
        }
        if (session.FramePending) return;
        session.FramePending = true;
        _dispatcher.BeginInvoke(() =>
        {
            session.FramePending = false;
            if (!session.Disposed)
                UpdatePreview(session);
        }, DispatcherPriority.Render);
    }
-            var pixW = formatted.PixelWidth;
+    private void UpdatePreview(WebSourceSession session)
-            var pixH = formatted.PixelHeight;
+    {
        var frame = session.LatestFrame;
        if (frame == null) return;
-            if (pixW < 1 || pixH < 1) return;
+        var (cropX, cropY, cropW, cropH) = frame.CropBounds ?? (0, 0, frame.Width, frame.Height);
        if (cropW < 1 || cropH < 1)
        {
            cropX = 0; cropY = 0;
            cropW = frame.Width; cropH = frame.Height;
        }
-            var pixels = new byte[pixW * pixH * 4];
+        // The preview is sized to the widget's alpha bounding box (the compositor
-            formatted.CopyPixels(pixels, pixW * 4, 0);
+        // gets the FULL canvas + CropBounds; the crop is only for the preview).
        // A fresh box (widget resizes / first content paints) mints a new bitmap
        // once — WPF re-renders a reused mutable bitmap after WritePixels, so
        // later frames only re-copy into the same one.
        if (session.PreviewBitmap == null
            || session.PreviewBitmap.PixelWidth != cropW
            || session.PreviewBitmap.PixelHeight != cropH)
        {
            session.PreviewBitmap = new WriteableBitmap(cropW, cropH, 96, 96, PixelFormats.Bgra32, null);
            PreviewBitmapChanged?.Invoke(session.Key, session.PreviewBitmap);
        }
-            var stride = pixW * 4;
+        var need = cropW * cropH * 4;
        var scratch = session.CropScratch is { } s && s.Length >= need
            ? s
            : (session.CropScratch = new byte[need]);
        var stride = frame.Stride;
        if (cropW == frame.Width && cropH == frame.Height && cropX == 0 && cropY == 0)
            Buffer.BlockCopy(frame.BgraPixels, 0, scratch, 0, need);
        else
            for (var r = 0; r < cropH; r++)
                Buffer.BlockCopy(frame.BgraPixels, (cropY + r) * stride + cropX * 4, scratch, r * cropW * 4, cropW * 4);
-            var (cropX, cropY, cropW, cropH) = FindContentBounds(pixels, pixW, pixH, stride);
+        session.PreviewBitmap.WritePixels(new Int32Rect(0, 0, cropW, cropH), scratch, cropW * 4, 0);
-            var outPixels = pixels;
+        // alpha[min/max/mean/zero%] — the one number that decides whether a widget's
-            if (cropW != pixW || cropH != pixH || cropX != 0 || cropY != 0)
+        // capture really has transparent margins (0% = opaque, ~100% if the page
        // painted transparent-only). Sampled every 16th pixel like the original log.
        if (!session.FirstCaptureLogged)
        {
            session.FirstCaptureLogged = true;
            AppLog.Write(
                $"WebView2Manager: first capture for '{session.Key}' {frame.Width}x{frame.Height} " +
                $"{AlphaStats(frame.BgraPixels, frame.Width, frame.Height, stride)} " +
                $"contentBounds=({cropX},{cropY},{cropW},{cropH})");
        }
        if (session.WidgetLogsRemaining > 0)
        {
            var dumpNo = 3 - session.WidgetLogsRemaining + 1;
            session.WidgetLogsRemaining--;
            AppLog.Write(
                $"WebView2Manager: widget capture [{dumpNo}/3] for '{session.Key}' {frame.Width}x{frame.Height} " +
                $"{AlphaStats(frame.BgraPixels, frame.Width, frame.Height, stride)} " +
                $"contentBounds=({cropX},{cropY},{cropW},{cropH})");
        }
    }
    private static string AlphaStats(byte[] pixels, int pixW, int pixH, int stride)
    {
        int minA = 255, maxA = 0;
        long sumA = 0, nA = 0, zeroA = 0;
        for (var y = 0; y < pixH; y += 16)
        {
            var row = y * stride;
            for (var x = 0; x < pixW; x += 16)
            {
-                var dstStride = cropW * 4;
+                var a = pixels[row + x * 4 + 3];
-                outPixels = new byte[dstStride * cropH];
+                if (a < minA) minA = a;
-                for (var r = 0; r < cropH; r++)
+                if (a > maxA) maxA = a;
-                    Buffer.BlockCopy(pixels, (cropY + r) * stride + cropX * 4, outPixels, r * dstStride, dstStride);
+                sumA += a;
                if (a == 0) zeroA++;
                nA++;
            }
            var wb = new WriteableBitmap(cropW, cropH, 96, 96, PixelFormats.Bgra32, null);
            wb.WritePixels(new Int32Rect(0, 0, cropW, cropH), outPixels, cropW * 4, 0);
            wb.Freeze();
            session.LatestFrame = new VideoFrame(cropW, cropH, outPixels);
            _ = _dispatcher.BeginInvoke(() =>
            {
                PreviewBitmapChanged?.Invoke(sourceId, wb);
            });
        }
        catch (ObjectDisposedException) { }
        catch (InvalidOperationException) { }
        catch (Exception ex)
        {
            AppLog.Write($"WebView2Manager: capture failed for '{sourceId}': {ex.Message}");
        }
        return $"alpha[min={minA},max={maxA},mean={sumA / (double)nA:F1},zero={100.0 * zeroA / nA:F1}%]";
    }
    private void RemoveSession(string sourceId)
    {
        if (!_sessions.TryGetValue(sourceId, out var session)) return;
        session.Disposed = true;
-        session.CaptureTimer.Stop();
+
-        _hostPanel.Children.Remove(session.Control);
+        var src = session.Source;
-        try { session.Control.Dispose(); } catch { }
+        if (src != null)
        {
            if (session.FrameHandler != null)
                src.FrameAvailable -= session.FrameHandler;
            _ = SafeStopAsync(src);
        }
        try { session.Controller?.Close(); } catch { }
        session.Web = null;
        _sessions.Remove(sourceId);
    }
    private static async Task SafeStopAsync(IScreenCaptureSource source)
    {
        try { await source.StopAsync(); }
        catch (Exception ex) { AppLog.Write($"WebView2Manager: stopping web capture failed: {ex.Message}"); }
    }
    public void Dispose()
    {
        foreach (var id in _sessions.Keys.ToList())
            RemoveSession(id);
    }
-}
+}
@@ -0,0 +1,122 @@
 using System;
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.Runtime.InteropServices;
 using System.Text;
 using ytLive.Models;
 namespace ytLive.Services;
 /// <summary>
 /// Win32 implementation of <see cref="IWindowEnumerator"/>. Enumerates visible
 /// top-level windows for the "Capture Window…" submenu, mirroring the style of
 /// <see cref="Win32FullScreenDetector"/>: visible, non-cloaked, zero-rect
 /// excluded, and windows belonging to this process excluded (the app must never
 /// offer itself for pinning). Ordered by process name, then title.
 /// </summary>
 public sealed class Win32WindowEnumerator : IWindowEnumerator
 {
    private static readonly IntPtr OwnProcessId = new(Environment.ProcessId);
    public IReadOnlyList<WindowInfo> Enumerate()
    {
        var results = new List<WindowInfo>();
        EnumWindows((hwnd, _) =>
        {
            if (TryDescribe(hwnd, out var info))
                results.Add(info);
            return true; // keep enumerating
        }, IntPtr.Zero);
        results.Sort(static (a, b) =>
        {
            var byProcess = string.Compare(a.ProcessName, b.ProcessName, StringComparison.OrdinalIgnoreCase);
            return byProcess != 0 ? byProcess
                : string.Compare(a.Title, b.Title, StringComparison.OrdinalIgnoreCase);
        });
        return results;
    }
    private static bool TryDescribe(IntPtr hwnd, out WindowInfo info)
    {
        info = null!;
        if (GetWindowThreadProcessId(hwnd, out var pid) == 0) return false;
        if (pid == 0 || new IntPtr((long)pid) == OwnProcessId) return false;
        if (!IsWindowVisible(hwnd)) return false;
        if (IsCloaked(hwnd)) return false;
        if (!TryGetRect(hwnd, out var rect) || rect.Right <= rect.Left || rect.Bottom <= rect.Top) return false;
        var title = GetTitle(hwnd);
        if (string.IsNullOrWhiteSpace(title)) return false;
        var processName = ProcessName((int)pid);
        if (string.IsNullOrWhiteSpace(processName)) return false;
        info = new WindowInfo(title, processName, hwnd.ToInt64(), (int)pid);
        return true;
    }
    private static string ProcessName(int pid)
    {
        try
        {
            using var process = Process.GetProcessById(pid);
            return process.ProcessName;
        }
        catch { return string.Empty; }
    }
    private static string GetTitle(IntPtr hwnd)
    {
        var length = GetWindowTextLength(hwnd);
        if (length <= 0) return string.Empty;
        var sb = new StringBuilder(length + 1);
        GetWindowText(hwnd, sb, sb.Capacity);
        return sb.ToString();
    }
    private static bool IsCloaked(IntPtr hwnd)
    {
        const int DWMWA_CLOAKED = 14;
        var cloaked = 0;
        return DwmGetWindowAttribute(hwnd, DWMWA_CLOAKED, out cloaked, sizeof(int)) == 0 && cloaked != 0;
    }
    private static bool TryGetRect(IntPtr hwnd, out Rect rect)
    {
        rect = default;
        return GetWindowRect(hwnd, out rect);
    }
    [StructLayout(LayoutKind.Sequential)]
    private struct Rect
    {
        public int Left;
        public int Top;
        public int Right;
        public int Bottom;
    }
    private delegate bool EnumWindowsProc(IntPtr hwnd, IntPtr lParam);
    [DllImport("user32.dll")]
    private static extern bool EnumWindows(EnumWindowsProc lpEnumFunc, IntPtr lParam);
    [DllImport("user32.dll")]
    private static extern bool IsWindowVisible(IntPtr hWnd);
    [DllImport("user32.dll", CharSet = CharSet.Unicode)]
    private static extern int GetWindowText(IntPtr hWnd, StringBuilder lpString, int nMaxCount);
    [DllImport("user32.dll", CharSet = CharSet.Unicode)]
    private static extern int GetWindowTextLength(IntPtr hWnd);
    [DllImport("user32.dll")]
    private static extern uint GetWindowThreadProcessId(IntPtr hWnd, out uint lpdwProcessId);
    [DllImport("user32.dll")]
    private static extern bool GetWindowRect(IntPtr hWnd, out Rect lpRect);
    [DllImport("dwmapi.dll")]
    private static extern int DwmGetWindowAttribute(IntPtr hwnd, int dwAttribute, out int pvAttribute, int cbAttribute);
 }
@@ -15,22 +15,60 @@ public class YouTubeAuthService
 {
    private const string AuthorizationEndpoint = "https://accounts.google.com/o/oauth2/v2/auth";
    private const string TokenEndpoint = "https://oauth2.googleapis.com/token";
-    private const string Scope = "https://www.googleapis.com/auth/youtube https://www.googleapis.com/auth/youtube.force-ssl";
+    /// <summary>
    /// The single scope the app requests: <c>auth/youtube</c> ("Manage your YouTube
    /// account"). It is the **broadest** YouTube scope and is unavoidable — no narrower one
    /// covers live broadcast create/transition, and Google's own <c>liveBroadcasts.insert</c>
    /// reference lists it as an accepted alternative to <c>youtube.force-ssl</c>, so every
    /// endpoint this app touches (<c>channels</c>, <c>liveBroadcasts</c>, <c>liveStreams</c>,
    /// <c>liveChat</c>, <c>playlistItems</c>) is covered by it.
    ///
    /// <para><c>auth/youtube.force-ssl</c> used to be requested alongside it and was
    /// <b>dropped 2026-09-28 as redundant</b>: its grant is "see, edit, and permanently delete
    /// your YouTube videos, ratings, comments and captions", a strict subset of what
    /// <c>auth/youtube</c> already grants. Requesting both meant two consent lines and two
    /// scopes to justify for one capability. Removing a scope can never narrow capability,
    /// because the scope being kept is the broader of the two.
    ///
    /// No forced re-consent: a refresh token keeps the scopes it was originally granted, so an
    /// existing session is unaffected; the reduced set applies from the next fresh sign-in.</para>
    /// </summary>
    private const string Scope = "https://www.googleapis.com/auth/youtube";
    private readonly string _clientId;
    private readonly string _clientSecret;
    private readonly HttpClient _http;
    private readonly Action<YouTubeChannel>? _sessionChanged;
    private readonly Action<string> _openBrowser;
    /// <summary>Serialises "take over from the previous attempt". Without this, two
    /// overlapping calls both see a free port and race to bind it, which is the same
    /// failure the cancel-and-await is meant to prevent.</summary>
    private readonly SemaphoreSlim _authGate = new(1, 1);
    /// <summary>The attempt currently holding the loopback callback port, if any.
    /// A creator who abandons the Google account chooser gives the app no signal, so
    /// the attempt simply waits out its 5-minute timeout while still holding port
    /// 8765 — and a retry in that window cannot bind. A new attempt cancels and
    /// awaits the abandoned one first, which releases the port (creator report
    /// 2026-09-27: "cannot sign-in because the callback url was not released").
    /// Both fields below are only touched while holding <see cref="_authGate"/>.</summary>
    private Task<YouTubeChannel?>? _authInFlight;
    private CancellationTokenSource? _authCts;
    public YouTubeChannel? CurrentChannel { get; private set; }
    public YouTubeAuthService(string clientId, string clientSecret, HttpClient? http = null,
-        Action<YouTubeChannel>? sessionChanged = null)
+        Action<YouTubeChannel>? sessionChanged = null,
        Action<string>? openBrowser = null)
    {
        _clientId = clientId;
        _clientSecret = clientSecret;
        _http = http ?? new HttpClient();
        _sessionChanged = sessionChanged;
        // Seam: the real flow shells out to the default browser, which a test must not do.
        _openBrowser = openBrowser ?? (url =>
            Process.Start(new ProcessStartInfo(url) { UseShellExecute = true }));
    }
    /// <summary>Replaces the current session (used when a saved token loads at startup).</summary>
@@ -65,23 +103,53 @@ public class YouTubeAuthService
    public async Task<YouTubeChannel?> AuthenticateAsync()
    {
        const int port = 8765;
        var redirectUri = $"http://localhost:{port}/oauth2/callback";
        if (string.IsNullOrWhiteSpace(_clientId) || string.IsNullOrWhiteSpace(_clientSecret))
            return null;
        // Taking over from an abandoned attempt has to be atomic: cancel it, wait for
        // it to actually let go of the port, then bind. Letting the gate go before the
        // bind reopens the race the takeover exists to close.
        Task<YouTubeChannel?> attempt;
        await _authGate.WaitAsync().ConfigureAwait(false);
        try
        {
            var previousCts = _authCts;
            _authCts = null;
            previousCts?.Cancel();
            if (_authInFlight is { } previous)
            {
                try { await previous.ConfigureAwait(false); } catch { /* its result is irrelevant */ }
                _authInFlight = null;
            }
            var cts = new CancellationTokenSource(TimeSpan.FromMinutes(5));
            _authCts = cts;
            _authInFlight = attempt = RunAuthFlowAsync(cts.Token);
        }
        finally
        {
            _authGate.Release();
        }
        return await attempt.ConfigureAwait(false);
    }
    private async Task<YouTubeChannel?> RunAuthFlowAsync(CancellationToken cancellationToken)
    {
        const int port = 8765;
        var redirectUri = $"http://localhost:{port}/oauth2/callback";
        using var listener = new HttpListener();
        listener.Prefixes.Add($"{redirectUri}/");
        listener.Start();
-        Process.Start(new ProcessStartInfo(GetAuthorizationUrl(redirectUri)) { UseShellExecute = true });
+        _openBrowser(GetAuthorizationUrl(redirectUri));
        HttpListenerContext context;
        try
        {
-            using var cts = new CancellationTokenSource(TimeSpan.FromMinutes(5));
+            context = await listener.GetContextAsync().WaitAsync(cancellationToken);
            context = await listener.GetContextAsync().WaitAsync(cts.Token);
        }
        catch (OperationCanceledException)
        {
@@ -6,16 +6,22 @@ namespace ytLive.Services;
 /// <summary>
 /// Polls YouTube Live Chat API for messages.
-/// YouTube doesn't have WebSocket for chat — polling is the only option.
+/// YouTube doesn't have WebSocket for chat — polling is the only option. The
 /// cadence follows the server's <c>pollingIntervalMillis</c> (the streamList
 /// connection semantics: reconnect with nextPageToken on that cadence, never
 /// faster than the refresh rate — YouTube rejects requests sent too quickly).
 /// The chat feed IS YouTube's event feed: Super Chats, stickers, memberships,
 /// gifts and milestones arrive here as typed messages (see <see cref="ChatEventKind"/>).
 /// </summary>
 public class YouTubeChatService : IDisposable
 {
    private readonly YouTubeAuthService _auth;
-    private readonly HttpClient _http = new();
+    private readonly HttpClient _http;
    private Timer? _pollTimer;
    private string? _nextPageToken;
    private string? _liveChatId;
    private bool _isRunning;
    private int _intervalMs = 2000;
    public event Action<ChatMessage>? MessageReceived;
@@ -24,9 +30,10 @@ public class YouTubeChatService : IDisposable
        PropertyNameCaseInsensitive = true
    };
-    public YouTubeChatService(YouTubeAuthService auth)
+    public YouTubeChatService(YouTubeAuthService auth, HttpClient? http = null)
    {
        _auth = auth;
        _http = http ?? new HttpClient();
    }
    public void Start(string liveChatId, int pollIntervalMs = 2000)
@@ -34,7 +41,9 @@ public class YouTubeChatService : IDisposable
        _liveChatId = liveChatId;
        _isRunning = true;
        _nextPageToken = null;
-        _pollTimer = new(async _ => await Poll(), null, 0, pollIntervalMs);
+        _intervalMs = Math.Clamp(pollIntervalMs, 1000, 6000);
        _pollTimer = new Timer(async _ => await Poll(), null, Timeout.Infinite, Timeout.Infinite);
        _pollTimer.Change(0, Timeout.Infinite);
    }
    public void Stop()
@@ -44,16 +53,24 @@ public class YouTubeChatService : IDisposable
        _pollTimer = null;
    }
    /// <summary>TASK 41: injects a synthetic message through the exact seam the real
    /// poll uses (MessageReceived), so a simulated member / SuperChat / subscriber
    /// event renders through the whole overlay pipeline. YouTube's insert API only
    /// creates text messages — these events are local-only by design and never
    /// reach YouTube (marked <see cref="ChatMessage.IsSimulated"/>).</summary>
    public void InjectSimulatedMessage(ChatMessage message)
        => MessageReceived?.Invoke(message);
    private async Task Poll()
    {
        if (!_isRunning || _liveChatId == null || _auth.CurrentChannel == null) return;
        try
        {
            if (!_isRunning || _liveChatId == null || _auth.CurrentChannel == null) return;
            if (_auth.CurrentChannel.TokenExpiry <= DateTime.UtcNow.AddMinutes(5))
                await _auth.RefreshToken();
-            var url = $"https://www.googleapis.com/youtube/v3/liveChat/messages?liveChatId={_liveChatId}&part=snippet,authorDetails&maxResults=50";
+            var url = $"https://www.googleapis.com/youtube/v3/liveChat/messages?liveChatId={_liveChatId}&part=snippet,authorDetails&maxResults=2000";
            if (_nextPageToken != null)
                url += $"&pageToken={_nextPageToken}";
@@ -62,76 +79,182 @@ public class YouTubeChatService : IDisposable
            if (!response.IsSuccessStatusCode) return;
            var json = await response.Content.ReadAsStringAsync();
-            var data = JsonSerializer.Deserialize<JsonElement>(json);
+            var page = ParsePage(json);
-            if (data.TryGetProperty("nextPageToken", out var token))
+            if (page.NextPageToken != null)
-                _nextPageToken = token.GetString();
+                _nextPageToken = page.NextPageToken;
-
+            if (page.PollIntervalMs > 0 && page.PollIntervalMs != _intervalMs)
-            if (!data.TryGetProperty("items", out var items)) return;
+                _intervalMs = page.PollIntervalMs;
            foreach (var item in items.EnumerateArray())
            {
                var snippet = item.GetProperty("snippet");
                var author = item.GetProperty("authorDetails");
                var type = snippet.GetProperty("type").GetString() ?? "textMessageEvent";
                var message = new ChatMessage
                {
                    Id = item.GetProperty("id").GetString()!,
                    AuthorName = author.GetProperty("displayName").GetString()!,
                    AuthorChannelId = author.GetProperty("channelId").GetString()!,
                    AuthorImageUrl = author.GetProperty("profileImageUrl").GetString()!,
                    Timestamp = DateTime.Parse(snippet.GetProperty("publishedAt").GetString()!),
                    IsMember = author.GetProperty("isChatSponsor").GetBoolean(),
                    MembershipLevel = author.TryGetProperty("badgeText", out var badgeText)
                        ? badgeText.GetString()
                        : null
                };
                switch (type)
                {
                    case "superChatEvent":
                        message.IsSuperChat = true;
                        if (snippet.TryGetProperty("superChatDetails", out var scDetails))
                        {
                            message.SuperChatAmount = scDetails.TryGetProperty("amountMicros", out var amt)
                                ? amt.GetDouble() / 1_000_000.0
                                : 0;
                            message.SuperChatCurrency = scDetails.TryGetProperty("currency", out var cur)
                                ? cur.GetString()
                                : null;
                            message.Message = scDetails.TryGetProperty("userComment", out var comment)
                                ? comment.GetString() ?? string.Empty
                                : string.Empty;
                        }
                        break;
                    case "newSponsorEvent":
                        message.Message = $"🎉 {message.AuthorName} became a member!";
                        if (snippet.TryGetProperty("membershipDetails", out var memDetails))
                        {
                            message.MembershipLevel = memDetails.TryGetProperty("memberLevelName", out var level)
                                ? level.GetString()
                                : message.MembershipLevel;
                        }
                        break;
                    default: // textMessageEvent
                        message.Message = snippet.TryGetProperty("textMessageDetails", out var textDetails)
                            ? textDetails.TryGetProperty("messageText", out var text)
                                ? text.GetString() ?? string.Empty
                                : string.Empty
                            : string.Empty;
                        break;
                }
            foreach (var message in page.Messages)
                MessageReceived?.Invoke(message);
            }
        }
        catch (Exception ex)
        {
            System.Diagnostics.Debug.WriteLine($"Chat poll error: {ex.Message}");
        }
        finally
        {
            // Re-arm the one-shot poll on the server's cadence. Guarded by
            // _isRunning so a concurrent Stop() (dispose + null) can't race a
            // Change() back onto the disposed timer.
            if (_isRunning)
                _pollTimer?.Change(_intervalMs, Timeout.Infinite);
        }
    }
    /// <summary>One liveChat/messages page → typed chat messages + pagination +
    /// the server's poll cadence. Internal + separated from the HTTP so the six
    /// event parses are deterministically testable without any network.</summary>
    internal static ChatPage ParsePage(string json)
    {
        var data = JsonSerializer.Deserialize<JsonElement>(json);
        var messages = new List<ChatMessage>();
        var nextPageToken = data.TryGetProperty("nextPageToken", out var token)
            ? token.GetString()
            : null;
        var intervalMs = data.TryGetProperty("pollingIntervalMillis", out var interval)
            && interval.ValueKind == JsonValueKind.Number
            ? interval.GetInt32()
            : 0;
        if (!data.TryGetProperty("items", out var items)) return new ChatPage(messages, nextPageToken, intervalMs);
        foreach (var item in items.EnumerateArray())
        {
            var snippet = item.GetProperty("snippet");
            var type = snippet.TryGetProperty("type", out var t) && t.ValueKind == JsonValueKind.String
                ? t.GetString()
                : "textMessageEvent";
            var message = new ChatMessage
            {
                Id = item.TryGetProperty("id", out var idProp) ? idProp.GetString() ?? Guid.NewGuid().ToString() : Guid.NewGuid().ToString(),
                Timestamp = DateTime.UtcNow,
            };
            if (item.TryGetProperty("authorDetails", out var author))
            {
                message.AuthorName = author.TryGetProperty("displayName", out var dn) ? dn.GetString() ?? string.Empty : string.Empty;
                message.AuthorChannelId = author.TryGetProperty("channelId", out var cid) ? cid.GetString() ?? string.Empty : string.Empty;
                message.AuthorImageUrl = author.TryGetProperty("profileImageUrl", out var im) ? im.GetString() ?? string.Empty : string.Empty;
                message.IsMember = author.TryGetProperty("isChatSponsor", out var sp) ? sp.GetBoolean() : false;
                message.MembershipLevel = author.TryGetProperty("badgeText", out var badge)
                    ? badge.GetString()
                    : null;
            }
            if (snippet.TryGetProperty("publishedAt", out var published)
                && DateTime.TryParse(published.GetString(), out var publishedAt))
                message.Timestamp = publishedAt;
            switch (type)
            {
                case "superChatEvent":
                    message.IsSuperChat = true;
                    message.Kind = ChatEventKind.SuperChat;
                    if (snippet.TryGetProperty("superChatDetails", out var scDetails))
                    {
                        if (scDetails.TryGetProperty("displayString", out var display)
                            && display.ValueKind == JsonValueKind.String)
                            message.SuperChatDisplayString = display.GetString();
                        if (scDetails.TryGetProperty("amountMicros", out var amt)
                            && amt.ValueKind == JsonValueKind.Number)
                            message.SuperChatAmount = amt.GetDouble() / 1_000_000.0;
                        message.SuperChatCurrency = scDetails.TryGetProperty("currency", out var cur)
                            ? cur.GetString()
                            : null;
                        message.Message = scDetails.TryGetProperty("userComment", out var comment)
                            ? comment.GetString() ?? string.Empty
                            : string.Empty;
                    }
                    break;
                case "superStickerEvent":
                    message.Kind = ChatEventKind.SuperSticker;
                    if (snippet.TryGetProperty("superStickerDetails", out var stickerDetails))
                    {
                        message.SuperStickerDescription = stickerDetails.TryGetProperty("stickerDescription", out var desc)
                            ? desc.GetString()
                            : stickerDetails.TryGetProperty("description", out var descAlt)
                                ? descAlt.GetString()
                                : null;
                        if (stickerDetails.TryGetProperty("displayString", out var display)
                            && display.ValueKind == JsonValueKind.String)
                            message.SuperChatDisplayString = display.GetString();
                        message.SuperChatCurrency = stickerDetails.TryGetProperty("currency", out var cur)
                            ? cur.GetString()
                            : null;
                        message.Message = stickerDetails.TryGetProperty("userComment", out var comment)
                            ? comment.GetString() ?? string.Empty
                            : string.Empty;
                    }
                    break;
                case "newSponsorEvent":
                    message.Kind = ChatEventKind.NewMember;
                    message.IsMember = true;
                    message.Message = $"🎉 {message.AuthorName} became a member!";
                    if (snippet.TryGetProperty("membershipDetails", out var memDetails))
                    {
                        message.MembershipLevel = memDetails.TryGetProperty("memberLevelName", out var level)
                            ? level.GetString()
                            : message.MembershipLevel;
                    }
                    break;
                case "membershipGiftingEvent":
                    message.Kind = ChatEventKind.MemberGift;
                    if (snippet.TryGetProperty("membershipGiftingDetails", out var giftingDetails)
                        && giftingDetails.TryGetProperty("giftNewMembersCount", out var count)
                        && count.ValueKind == JsonValueKind.Number)
                        message.GiftNewMembersCount = count.GetInt32();
                    message.Message = message.GiftNewMembersCount > 0
                        ? $"🎁 {message.AuthorName} gifted {message.GiftNewMembersCount} memberships!"
                        : $"🎁 {message.AuthorName} gifted memberships!";
                    break;
                case "giftMembershipReceivedEvent":
                    message.Kind = ChatEventKind.GiftReceived;
                    if (snippet.TryGetProperty("giftMembershipReceivedDetails", out var giftReceived)
                        && giftReceived.TryGetProperty("gifterName", out var gifter))
                        message.GifterName = gifter.GetString();
                    message.Message = message.GifterName != null
                        ? $"{message.GifterName} gifted you a membership! 🎉"
                        : $"{message.AuthorName} received a membership gift! 🎉";
                    break;
                case "memberMilestoneChatEvent":
                    message.Kind = ChatEventKind.MemberMilestone;
                    message.IsMember = true;
                    message.Message = snippet.TryGetProperty("textMessageDetails", out var msd)
                        ? msd.TryGetProperty("messageText", out var mst)
                            ? mst.GetString() ?? string.Empty
                            : string.Empty
                        : string.Empty;
                    if (message.Message.Length > 0)
                    {
                        var match = System.Text.RegularExpressions.Regex.Match(message.Message, @"(\d+)\s*month", System.Text.RegularExpressions.RegexOptions.IgnoreCase);
                        if (match.Success && int.TryParse(match.Groups[1].Value, out var months))
                            message.MilestoneMonths = months;
                    }
                    break;
                default: // textMessageEvent and anything else — anonymous chat rows only.
                    message.Message = snippet.TryGetProperty("textMessageDetails", out var textDetails)
                        ? textDetails.TryGetProperty("messageText", out var text)
                            ? text.GetString() ?? string.Empty
                            : string.Empty
                        : string.Empty;
                    break;
            }
            messages.Add(message);
        }
        return new ChatPage(messages, nextPageToken, intervalMs);
    }
    public void Dispose()
@@ -140,3 +263,7 @@ public class YouTubeChatService : IDisposable
        _http.Dispose();
    }
 }
 /// <summary>Decoded liveChat/messages response: the messages + where to resume +
 /// how long to wait before reconnecting.</summary>
 internal sealed record ChatPage(List<ChatMessage> Messages, string? NextPageToken, int PollIntervalMs);
@@ -29,7 +29,12 @@ public class YouTubeStreamService
        return true;
    }
-    public async Task<string?> CreateBroadcast(string title, string description, DateTime scheduledStartTime, string? streamId = null)
+    /// <param name="scheduledStartTime"/> — note there is deliberately NO streamId
    /// parameter (2026-10-04). It used to be here and was ignored: sending
    /// `contentDetails.boundStreamId` does not bind the broadcast. A parameter that looks
    /// meaningful but cannot affect the outcome is a defect — it is exactly what made the
    /// week-long misdiagnosis possible — so the signature now says what it actually does.</param>
    public async Task<string?> CreateBroadcast(string title, string description, DateTime scheduledStartTime)
    {
        if (!await EnsureToken()) return null;
@@ -50,9 +55,16 @@ public class YouTubeStreamService
                selfDeclaredMadeForKids = false
            },
            // One-click go-live (TASK 5 design decision 1): auto start/stop with
-            // no monitor stream and low latency. A reusable stream, when given,
+            // no monitor stream and low latency.
-            // binds here (boundStreamId) so no second bind round-trip is needed.
+            //
-            contentDetails = BuildContentDetails(streamId)
+            // ⛔ `boundStreamId` is DELIBERATELY NOT SENT HERE (2026-10-04). It used to
            // be, on the assumption that binding at insert saved a round-trip. It does
            // not bind anything — proven: the insert was accepted, sibling fields in
            // this same object took effect, and the broadcast still read `bound=NONE`,
            // stayed in lifeCycleStatus `created`, and never went live. Binding is done
            // by the explicit BindBroadcastAsync call instead. Leaving the field out
            // stops the next reader trusting it; see that method for the full account.
            contentDetails = BuildContentDetails()
        };
        _http.DefaultRequestHeaders.Authorization = new("Bearer", _auth.CurrentChannel!.AccessToken);
@@ -66,17 +78,17 @@ public class YouTubeStreamService
        return data.GetProperty("id").GetString();
    }
-    private static Dictionary<string, object?> BuildContentDetails(string? streamId)
+    private static Dictionary<string, object?> BuildContentDetails()
    {
-        var details = new Dictionary<string, object?>
+        // No `boundStreamId` here on purpose — it does not bind (proven 2026-10-04).
        // Binding is the explicit BindBroadcastAsync call; see CreateBroadcast.
        return new Dictionary<string, object?>
        {
            ["enableAutoStart"] = true,
            ["enableAutoStop"] = true,
            ["enableMonitorStream"] = false,
            ["latencyPreference"] = "low",
        };
        if (streamId != null) details["boundStreamId"] = streamId;
        return details;
    }
    /// <summary>
@@ -124,6 +136,264 @@ public class YouTubeStreamService
        return $"YouTube rejected the update ({(int)response.StatusCode})";
    }
    /// <summary>Proper close-out (TASK 9 design decision 6 — implemented 2026-09-01;
    /// until then we relied entirely on enableAutoStop, leaving viewers on a frozen
    /// "stream offline" screen for ~a minute): POST liveBroadcasts.transition
    /// broadcastStatus=complete. MUST be called AFTER the encoder closed the RTMP
    /// push so no frames post-date the end. **Pre-flight (2026-09-22):** the POST is
    /// now gated on the broadcast's OWN lifeCycleStatus — every 2026-09-22 end
    /// logged 403 invalidTransition because enableAutoStop/YouTube had already marked
    /// the broadcast complete; a blind complete only earned the 403 + log noise. We
    /// skip ONLY on a confirmed already-ended status (complete/revoked) — an
    /// inconclusive check still posts (old behavior) rather than silently stranding a
    /// live broadcast. The POST is never-throwing: a rare still-failing transition
    /// surfaces as an error string, never a throw — the stop path must not fail over a
    /// cosmetic close-out.</summary>
    public async Task<string?> EndBroadcastAsync(string broadcastId)
    {
        if (!await EnsureToken()) return "not signed in";
        _http.DefaultRequestHeaders.Authorization = new("Bearer", _auth.CurrentChannel!.AccessToken);
        var lifeCycle = await GetLifeCycleStatusAsync(broadcastId);
        if (lifeCycle is "complete" or "revoked")
        {
            // Already ended (autoStop/YouTube raced us) — a blind complete only
            // earns a 403 + noise. enableAutoStop finished it.
            AppLog.Write($"End close-out: {broadcastId} already at lifeCycleStatus '{lifeCycle}' — skipping complete");
            return null;
        }
        var response = await _http.PostAsync(
            $"{ApiBase}/liveBroadcasts/transition?broadcastStatus=complete&id={Uri.EscapeDataString(broadcastId)}&part=status",
            content: null);
        if (response.IsSuccessStatusCode) return null;
        var body = await response.Content.ReadAsStringAsync();
        AppLog.Write($"Broadcast transition(complete) failed ({(int)response.StatusCode}): {body}");
        return $"YouTube rejected the end transition ({(int)response.StatusCode})";
    }
    /// <summary>One liveBroadcasts.list (part=status) read of the broadcast's own
    /// lifeCycleStatus — the only reliable "can we complete?" signal. Null when the
    /// list fails or the status is missing (caller degrades gracefully).</summary>
    private async Task<string?> GetLifeCycleStatusAsync(string broadcastId)
    {
        var response = await _http.GetAsync(
            $"{ApiBase}/liveBroadcasts?part=status&id={Uri.EscapeDataString(broadcastId)}");
        if (!response.IsSuccessStatusCode) return null;
        var json = JsonSerializer.Deserialize<JsonElement>(await response.Content.ReadAsStringAsync());
        if (!json.TryGetProperty("items", out var items) || items.GetArrayLength() == 0) return null;
        if (!items[0].TryGetProperty("status", out var status)) return null;
        return status.TryGetProperty("lifeCycleStatus", out var lifeCycle)
            ? lifeCycle.GetString()
            : null;
    }
    /// <summary>One compact log line answering the only question that matters while a
    /// stream is running: is the broadcast actually bound to the stream we are pushing
    /// to, and has it moved off `ready`?
    ///
    /// Added 2026-10-04 after two test runs proved the push itself is healthy — ffmpeg
    /// delivered 101,229 KiB video + 1,419 KiB audio over 112s with no socket error,
    /// yet `enableAutoStart` never fired and close-out 403'd with `invalidTransition`.
    /// The config is correct by Google's documentation (boundStreamId is a valid
    /// contentDetails field with no restriction against reusable streams), so the only
    /// way forward is to observe rather than guess. Everything the API reports about
    /// this broadcast and its stream goes in one greppable line:
    /// lifeCycleStatus (so the caller can stop asking once it is live), privacyStatus, the boundStreamId
    /// *compared against the stream we think we are pushing*, enableAutoStart/Stop, liveChatId
    /// presence, the stream's own status.streamStatus, and the CDN settings we declared.
    /// Never throws.</summary>
    public async Task<string?> LogBroadcastDiagnosticsAsync(string broadcastId, string? streamId)
    {
        if (!await EnsureToken()) return null;
        _http.DefaultRequestHeaders.Authorization = new("Bearer", _auth.CurrentChannel!.AccessToken);
        try
        {
            var broadcastList = await GetJsonAsync($"liveBroadcasts?part=status,contentDetails,snippet&id={Uri.EscapeDataString(broadcastId)}");
            // FIX 2026-10-04: liveBroadcasts.list returns a LIST wrapper, so the
            // broadcast lives at items[0]. The first version of this diagnostic read
            // the wrapper's root and reported every field as "?" — which then made
            // BoundMatches report a confident "NO-BINDING" from a parse that never
            // happened. A diagnostic that lies when it fails is worse than none.
            var broadcast = FirstItem(broadcastList);
            var read = broadcast.ValueKind == JsonValueKind.Object;
            var status = Nested(broadcast, "status");
            var details = Nested(broadcast, "contentDetails");
            var snippet = Nested(broadcast, "snippet");
            var lifeCycle = Text(status, "lifeCycleStatus") ?? "?";
            var bound = Text(details, "boundStreamId");
            JsonElement? stream = string.IsNullOrWhiteSpace(streamId)
                ? null
                : await GetJsonAsync($"liveStreams?part=status,cdn&id={Uri.EscapeDataString(streamId)}");
            var streamItem = stream is { } present ? FirstItem(present) : default(JsonElement);
            AppLog.Write(
                $"Broadcast diag: id={broadcastId} lifeCycle={lifeCycle} privacy={Text(status, "privacyStatus") ?? "?"} " +
                $"recording={Text(status, "recordingStatus") ?? "?"} bound={(read ? (bound ?? "NONE") : "UNREAD")} " +
                $"expect={streamId ?? "none"} boundMatches={(read ? BoundMatches(bound, streamId) : "unread")} " +
                $"boundLastUpdate={Text(details, "boundStreamLastUpdateTimeMs") ?? "?"} " +
                $"autoStart={Flag(details, "enableAutoStart")} autoStop={Flag(details, "enableAutoStop")} " +
                $"liveChatId={(string.IsNullOrWhiteSpace(Text(snippet, "liveChatId")) ? "none" : "present")} | " +
                $"streamId={Text(streamItem, "id") ?? "none"} streamStatus={Text(Nested(streamItem, "status"), "streamStatus") ?? "?"} " +
                $"activeChat={(string.IsNullOrWhiteSpace(Text(Nested(streamItem, "status"), "activeLiveChatId")) ? "none" : "present")} " +
                $"cdn={Text(Nested(streamItem, "cdn"), "ingestionType") ?? "?"}/{Text(Nested(streamItem, "cdn"), "resolution") ?? "?"}@{Text(Nested(streamItem, "cdn"), "frameRate") ?? "?"}");
            return lifeCycle;
        }
        catch (Exception ex)
        {
            AppLog.Write($"Broadcast diag failed: {ex.Message}");
            return null;
        }
    }
    /// <summary>Descends into a `*.list` response and returns its single item. Every list
    /// endpoint wraps the resource in `items[]`, so reading the response root reads
    /// the wrapper and silently yields nothing — which is exactly the bug this
    /// exists to prevent. Returns <c>default</c> when there is no item (empty list,
    /// or a shape we do not recognise) so callers can tell "absent" from "present".</summary>
    internal static JsonElement FirstItem(JsonElement listResponse)
    {
        return listResponse.ValueKind == JsonValueKind.Object
            && listResponse.TryGetProperty("items", out var items)
            && items.ValueKind == JsonValueKind.Array
            && items.GetArrayLength() > 0
                ? items[0]
                : default;
    }
    /// <summary>The bound stream must be the one we are actually feeding. A mismatch is
    /// the failure mode where ingest succeeds (the reusable stream happily accepts the
    /// bytes) while the broadcast waits forever for a stream that is not sending.</summary>
    internal static string BoundMatches(string? boundStreamId, string? expectedStreamId)
    {
        if (string.IsNullOrWhiteSpace(boundStreamId)) return "NO-BINDING";
        if (string.IsNullOrWhiteSpace(expectedStreamId)) return "unknown";
        return boundStreamId == expectedStreamId ? "yes" : "MISMATCH";
    }
    private async Task<JsonElement> GetJsonAsync(string pathAndQuery)
    {
        var response = await _http.GetAsync($"{ApiBase}/{pathAndQuery}");
        if (!response.IsSuccessStatusCode)
        {
            AppLog.Write($"Broadcast diag GET {pathAndQuery.Split('?')[0]} failed ({(int)response.StatusCode})");
            return default;
        }
        return JsonSerializer.Deserialize<JsonElement>(await response.Content.ReadAsStringAsync());
    }
    private static JsonElement Nested(JsonElement parent, string name) =>
        parent.ValueKind == JsonValueKind.Object && parent.TryGetProperty(name, out var child) ? child : default;
    private static string? Text(JsonElement parent, string name) =>
        parent.ValueKind == JsonValueKind.Object && parent.TryGetProperty(name, out var value) && value.ValueKind == JsonValueKind.String
            ? value.GetString()
            : null;
    private static string Flag(JsonElement parent, string name) =>
        parent.ValueKind == JsonValueKind.Object && parent.TryGetProperty(name, out var value)
            ? (value.ValueKind == JsonValueKind.True ? "true" : value.ValueKind == JsonValueKind.False ? "false" : value.ValueKind.ToString())
            : "unset";
    /// <summary>Binds the broadcast to its stream — THE call that actually makes a broadcast
    /// go live, and the reason it took a week to find (2026-10-04).
    ///
    /// `POST liveBroadcasts/bind?id=…&streamId=…&part=id`, no request body, `youtube.force-ssl`.
    ///
    /// **Sending `contentDetails.boundStreamId` on `liveBroadcasts.insert` does NOT bind the
    /// broadcast.** Proven, not assumed: the insert carried `boundStreamId`, the API accepted the
    /// request (sibling fields in the same `contentDetails` — `enableAutoStart`, `enableAutoStop` —
    /// demonstrably took effect), and the created broadcast still came back
    /// `bound=NONE`. YouTube's own migration guide says so outright: *"a liveBroadcast must be bound
    /// to exactly one stream before the live broadcast can actually start. The broadcast is not bound
    /// to any streams at the time that it's created."*
    ///
    /// The failure it produces is a **silent stall, not an error**, which is why it survived so long:
    /// an unbound broadcast reports `lifeCycleStatus = created` ("incomplete settings, not ready to
    /// transition to a live or testing status"), so `enableAutoStart` has no bound stream to fire
    /// from, the broadcast never leaves `created`, and close-out then 403s with `invalidTransition`
    /// because `created → complete` is not a legal edge. Meanwhile ffmpeg pushes ~99 MB happily into
    /// the reusable stream, because a reusable stream accepts bytes for a broadcast that is not
    /// watching. Every symptom pointed away from the binding.
    ///
    /// Returns null on success, otherwise a human-readable error naming the ACTUAL cause.
    /// Never throws.</summary>
    public async Task<string?> BindBroadcastAsync(string broadcastId, string streamId)
    {
        if (!await EnsureToken()) return "not signed in";
        _http.DefaultRequestHeaders.Authorization = new("Bearer", _auth.CurrentChannel!.AccessToken);
        var response = await _http.PostAsync(
            $"{ApiBase}/liveBroadcasts/bind?part=id&id={Uri.EscapeDataString(broadcastId)}&streamId={Uri.EscapeDataString(streamId)}",
            content: null);
        if (response.IsSuccessStatusCode)
        {
            AppLog.Write($"Broadcast bound: {broadcastId} -> stream {streamId}");
            return null;
        }
        var body = await response.Content.ReadAsStringAsync();
        var reason = ErrorReason(body);
        AppLog.Write($"Broadcast bind failed ({(int)response.StatusCode}/{reason ?? "unknown"}) for {broadcastId} -> {streamId}: {body}");
        return BindFailureMessage((int)response.StatusCode, reason);
    }
    /// <summary>Pulls `errors[0].reason` out of a Google API error body. Needed because
    /// "rejected the binding" alone is not actionable — the reason is what tells the
    /// creator whether to re-auth, wait, or suspect our own ordering.</summary>
    internal static string? ErrorReason(string body)
    {
        try
        {
            using var doc = JsonDocument.Parse(body);
            if (doc.RootElement.TryGetProperty("error", out var error)
                && error.TryGetProperty("errors", out var errors)
                && errors.GetArrayLength() > 0
                && errors[0].TryGetProperty("reason", out var reason))
                return reason.GetString();
        }
        catch (JsonException)
        {
            // A non-JSON error body tells us nothing actionable; the status code is enough.
        }
        return null;
    }
    /// <summary>Bind failures are NOT all "sign in again" (2026-10-04). Google documents six
    /// distinct reasons and only one is an auth problem, so a single sign-in message
    /// actively misdirects: `liveBroadcastBindingNotAllowed` in particular means OUR
    /// ordering is wrong, and telling the creator to re-authenticate would hide a bug in
    /// our own code behind a plausible excuse. Each documented reason gets its own text,
    /// because the caller's only lever is the string it shows.</summary>
    internal static string BindFailureMessage(int status, string? reason) => reason switch
    {
        "liveBroadcastBindingNotAllowed" =>
            "YouTube won't bind a broadcast in its current state — it may already be live. End the session and start again.",
        "liveStreamNotFound" =>
            "YouTube couldn't find the reusable stream. Sign in again so it can be recreated.",
        "liveBroadcastNotFound" =>
            "YouTube couldn't find the broadcast that was just created. Try again.",
        "liveStreamingNotEnabled" =>
            "This channel isn't enabled for live streaming — check the channel's live settings in YouTube Studio.",
        "insufficientLivePermissions" =>
            "This account doesn't have permission to stream live. Check the YouTube sign-in.",
        "internalError" =>
            "YouTube hit an internal error binding the stream. Try again.",
        "userRequestsExceededRateLimit" =>
            "YouTube is rate-limiting us. Wait a moment and try again.",
        // Unknown or absent reason: keep it verbatim. Never collapse distinct causes into
        // one bucket — an unmapped reason must stay greppable against the raw API response.
        null => $"YouTube rejected the stream binding (HTTP {status}, no reason in the body — see startup.log).",
        _ => $"YouTube rejected the stream binding (HTTP {status}, reason '{reason}' — see startup.log).",
    };
    /// <summary>Returns the channel's reusable stream (TASK 5 design decision 2):
    /// lists existing streams first and reuses the one with cdn.isReusable=true,
    /// creating it with variable resolution/frame rate on first use. Binding to a
@@ -209,43 +479,114 @@ public class YouTubeStreamService
        if (items.GetArrayLength() == 0) return null;
        var status = items[0].GetProperty("status");
-        var health = new StreamHealth
+        // The real API nests health as status.healthStatus = { status, lastUpdateTimeSeconds,
        // configurationIssues[] }. The flat "healthStatus":"bad" shape is our old wrong
        // assumption — accept both so neither crashes the report-by-exception poll.
        var health = new StreamHealth();
        var issueElements = new List<JsonElement>();
        if (status.TryGetProperty("healthStatus", out var healthStatus))
        {
-            HealthStatus = status.TryGetProperty("healthStatus", out var healthStatus)
+            if (healthStatus.ValueKind == JsonValueKind.String)
                ? healthStatus.GetString()
                : null,
        };
        if (status.TryGetProperty("configurationIssues", out var issues))
        {
            foreach (var issue in issues.EnumerateArray())
            {
-                var severity = issue.TryGetProperty("severity", out var sev) ? sev.GetString() : null;
+                health.HealthStatus = healthStatus.GetString();
                var type = issue.TryGetProperty("type", out var t) ? t.GetString() : null;
                health.ConfigurationIssues.Add(new StreamConfigurationIssue
                {
                    Severity = severity switch
                    {
                        "error" => StreamIssueSeverity.Error,
                        "warning" => StreamIssueSeverity.Warning,
                        _ => StreamIssueSeverity.Info,
                    },
                    Type = type,
                });
            }
            else if (healthStatus.TryGetProperty("status", out var inner) &&
                     inner.ValueKind == JsonValueKind.String)
            {
                health.HealthStatus = inner.GetString();
            }
            if (healthStatus.TryGetProperty("configurationIssues", out var nested))
                issueElements.AddRange(nested.EnumerateArray());
        }
        if (status.TryGetProperty("configurationIssues", out var flat))
            issueElements.AddRange(flat.EnumerateArray());
        foreach (var issue in issueElements)
        {
            var severity = issue.TryGetProperty("severity", out var sev) && sev.ValueKind == JsonValueKind.String
                ? sev.GetString()
                : null;
            var type = issue.TryGetProperty("type", out var t) && t.ValueKind == JsonValueKind.String
                ? t.GetString()
                : null;
            health.ConfigurationIssues.Add(new StreamConfigurationIssue
            {
                Severity = severity switch
                {
                    "error" => StreamIssueSeverity.Error,
                    "warning" => StreamIssueSeverity.Warning,
                    _ => StreamIssueSeverity.Info,
                },
                Type = type,
            });
        }
        return health;
    }
-    /// <summary>Returns the liveChatId for a broadcast by fetching its contentDetails.
+    /// <summary>TASK 41 — mock chat input: posts a real text message into the live
-    /// The liveChatId is needed to poll chat messages. Called after broadcast creation
+    /// chat via <c>liveChat/messages.insert</c>. Requires the same OAuth scopes the
-    /// in PrepareAndStartLiveAsync.</summary>
+    /// app already holds (youtube.force-ssl). Returns itself or a human-readable
-    public async Task<string?> GetBroadcastLiveChatIdAsync(string broadcastId)
+    /// error; never throws. The inserted message round-trips back through the normal
    /// chat poll (~2s) and renders through the live overlay path.</summary>
    public async Task<string?> InsertChatMessageAsync(string liveChatId, string messageText)
    {
        if (!await EnsureToken()) return "not signed in";
        var body = new
        {
            snippet = new
            {
                liveChatId,
                type = "textMessageEvent",
                textMessageDetails = new { messageText }
            }
        };
        _http.DefaultRequestHeaders.Authorization = new("Bearer", _auth.CurrentChannel!.AccessToken);
        var response = await _http.PostAsJsonAsync(
            $"{ApiBase}/liveChat/messages?part=snippet", body);
        if (response.IsSuccessStatusCode)
        {
            AppLog.Write($"Test chat message inserted into {liveChatId}");
            return null;
        }
        var errorBody = await response.Content.ReadAsStringAsync();
        AppLog.Write($"Chat message insert failed ({(int)response.StatusCode}): {errorBody}");
        return $"YouTube rejected the message ({(int)response.StatusCode})";
    }
    /// <summary>Resolves the broadcast's liveChatId (needed to poll chat). Two facts
    /// pin this down (2026-09-25, from the official liveBroadcasts reference + the
    /// GetLiveChatId.java sample):
    /// 1. It lives under <c>snippet.liveChatId</c> — <c>contentDetails</c> has no such
    ///    property, so part=contentDetails could NEVER resolve it (the "Chat polling
    ///    couldn't start" report).
    /// 2. YouTube only populates it once the broadcast is <c>live</c> (the sample lists
    ///    broadcastStatus=active) — fetching right after insert (lifecycleStatus
    ///    <c>ready</c>) returns no id. So this polls with a bounded retry, which the
    ///    caller must run AFTER the encoder starts pushing RTMP (enableAutoStart flips
    ///    the broadcast to live). Returns the id or null after the retries exhaust;
    ///    never throws.</summary>
    public async Task<string?> GetBroadcastLiveChatIdAsync(
        string broadcastId, int maxAttempts = 10, int delayMs = 2000)
    {
        for (var attempt = 0; attempt < maxAttempts; attempt++)
        {
            if (attempt > 0) await Task.Delay(delayMs);
            var liveChatId = await FetchLiveChatIdAsync(broadcastId);
            if (liveChatId != null) return liveChatId;
        }
        return null;
    }
    private async Task<string?> FetchLiveChatIdAsync(string broadcastId)
    {
        if (!await EnsureToken()) return null;
        _http.DefaultRequestHeaders.Authorization = new("Bearer", _auth.CurrentChannel!.AccessToken);
        var response = await _http.GetAsync(
-            $"{ApiBase}/liveBroadcasts?part=contentDetails&id={broadcastId}");
+            $"{ApiBase}/liveBroadcasts?part=snippet&id={broadcastId}");
        if (!response.IsSuccessStatusCode) return null;
        var json = await response.Content.ReadAsStringAsync();
@@ -253,8 +594,8 @@ public class YouTubeStreamService
        var items = data.GetProperty("items");
        if (items.GetArrayLength() == 0) return null;
-        var contentDetails = items[0].GetProperty("contentDetails");
+        var snippet = items[0].GetProperty("snippet");
-        if (contentDetails.TryGetProperty("liveChatId", out var liveChatId))
+        if (snippet.TryGetProperty("liveChatId", out var liveChatId))
            return liveChatId.GetString();
        return null;
@@ -0,0 +1,282 @@
 using System.Diagnostics;
 using System.Windows.Input;
 using ytLive.Helpers;
 using ytLive.Models;
 namespace ytLive.Services;
 /// <summary>
 /// Backing VM for the YPP pull-out (the "YPP" tab below Stream Settings on the
 /// Live screen's right edge). Shows the connected channel's current position
 /// toward the YPP tier thresholds (subscribers + 90-day uploads via the Data
 /// API), a compliance checklist (2FA/AdSense self-reported — channel standing is
 /// NOT exposed to ordinary apps, so the drawer deep-links to the Earn page for it)
 /// and the "what counts" education the creator would otherwise have to leave the
 /// app to find. Snapshots are appended to SQLite on every refresh so a later
 /// analytics slice can compute velocity/ETA from history.
 /// Drawer open/close lives here (mirrors LiveBroadcastFormViewModel).
 /// </summary>
 public sealed class YppTrackerViewModel : ViewModelBase
 {
    private const double BarMaxWidth = 220;
    private readonly Func<LayoutStore> _store;
    private readonly Func<ChannelStatsService> _stats;
    private readonly Func<bool> _isConnected;
    private readonly Func<string?> _displayName;
    private bool _isDrawerOpen;
    private bool _isLoading;
    private bool _isRefreshing;
    private string? _loadError;
    private string _displayNameText = string.Empty;
    private long _subscriberCount;
    private long _videoCount;
    private long _totalViews;
    private int _uploadsLast90Days;
    private bool _hasSnapshot;
    private bool _twoFactorEnabled;
    private bool _adsenseLinked;
    private DateTime? _lastRefreshedAtUtc;
    public YppTrackerViewModel(
        Func<LayoutStore> store,
        Func<ChannelStatsService> stats,
        Func<bool> isConnected,
        Func<string?> displayName)
    {
        _store = store;
        _stats = stats;
        _isConnected = isConnected;
        _displayName = displayName;
        RefreshCommand = new RelayCommand(_ => _ = RefreshAsync());
        ToggleDrawerCommand = new RelayCommand(_ => IsDrawerOpen = !IsDrawerOpen);
        CloseDrawerCommand = new RelayCommand(_ => IsDrawerOpen = false);
        OpenEarnCommand = new RelayCommand(_ => OpenUrl(EarnUrl));
        OpenTwoStepCommand = new RelayCommand(_ => OpenUrl(TwoStepVerificationUrl));
        OpenAdsenseCommand = new RelayCommand(_ => OpenUrl(AdsenseGuideUrl));
        (_twoFactorEnabled, _adsenseLinked) = _store().LoadYppChecklist();
        _lastRefreshedAtUtc = _store().LoadYppLastRefreshedAtUtc();
    }
    // Deep links — the parts of the checklist YouTube does NOT expose to any API
    // resolve in the browser; everything API-derived stays in-app.
    private const string EarnUrl = "https://www.youtube.com/earn";
    private const string TwoStepVerificationUrl = "https://myaccount.google.com/signinoptions/two-step-verification";
    private const string AdsenseGuideUrl = "https://support.google.com/youtube/answer/72851";
    public RelayCommand RefreshCommand { get; }
    public RelayCommand ToggleDrawerCommand { get; }
    public RelayCommand CloseDrawerCommand { get; }
    public RelayCommand OpenEarnCommand { get; }
    public RelayCommand OpenTwoStepCommand { get; }
    public RelayCommand OpenAdsenseCommand { get; }
    public bool IsDrawerOpen
    {
        get => _isDrawerOpen;
        set
        {
            if (SetProperty(ref _isDrawerOpen, value) && value)
                _ = EnsureLoadedAsync();
        }
    }
    public bool IsLoading
    {
        get => _isLoading;
        private set => SetProperty(ref _isLoading, value);
    }
    public bool IsSignedOut => !_isConnected();
    public string? LoadError
    {
        get => _loadError;
        private set => SetProperty(ref _loadError, value);
    }
    public string DisplayName => _displayNameText;
    // ─── Live numbers (from the Data API snapshot) ───
    public long SubscriberCount => _subscriberCount;
    public long VideoCount => _videoCount;
    public long TotalViews => _totalViews;
    public int UploadsLast90Days => _uploadsLast90Days;
    /// <summary>True once a snapshot has successfully captured at least once this
    /// session (drives the standing detail text's "sign in to load" state).</summary>
    public bool HasSnapshot => _hasSnapshot;
    // ─── Manual checklist (2FA / AdSense — no API exposes them) ───
    public bool TwoFactorEnabled
    {
        get => _twoFactorEnabled;
        set
        {
            if (SetProperty(ref _twoFactorEnabled, value))
                PersistChecklist();
        }
    }
    public bool AdSenseLinked
    {
        get => _adsenseLinked;
        set
        {
            if (SetProperty(ref _adsenseLinked, value))
                PersistChecklist();
        }
    }
    // ─── Progress rows (subscribers is fixed; uploads is a 3/90d bar) ───
    public double Tier1SubsProgress => Progress(SubscriberCount, YppThresholds.Tier1.Subscribers);
    public double Tier2SubsProgress => Progress(SubscriberCount, YppThresholds.Tier2Now.Subscribers);
    public double UploadsProgress => Progress(UploadsLast90Days, YppThresholds.UploadsRequiredPer90Days);
    public double Tier1SubsBarWidth => Progress(SubscriberCount, YppThresholds.Tier1.Subscribers) * BarMaxWidth;
    public double Tier2SubsBarWidth => Progress(SubscriberCount, YppThresholds.Tier2Now.Subscribers) * BarMaxWidth;
    public double UploadsBarWidth => Progress(UploadsLast90Days, YppThresholds.UploadsRequiredPer90Days) * BarMaxWidth;
    public string Tier1SubsText => $"{SubscriberCount:N0} / {YppThresholds.Tier1.Subscribers:N0}";
    public string Tier2SubsText => $"{SubscriberCount:N0} / {YppThresholds.Tier2Now.Subscribers:N0}";
    public string UploadsText => $"{UploadsLast90Days} / {YppThresholds.UploadsRequiredPer90Days} in the last 90 days";
    public string StandingDetailText
    {
        get
        {
            if (!HasSnapshot) return "Sign in to load your channel's progress from YouTube.";
            return "Channel standing isn't exposed to YouTube apps — check the Earn page for your live status.";
        }
    }
    public string LastUpdatedText
    {
        get
        {
            if (_lastRefreshedAtUtc == null) return "Not refreshed yet";
            var local = _lastRefreshedAtUtc.Value.ToLocalTime();
            return local.Date == DateTime.Today
                ? $"Updated today at {local:HH:mm}"
                : $"Updated {local:g}";
        }
    }
    public string WhatCountsText { get; } =
        "Long-form watch hours: valid public VODs and livestreams watched in the trailing 12 " +
        "months — Shorts-feed views don't count, and private, unlisted, deleted or ad-campaign " +
        "time is excluded. Shorts views: valid public Shorts viewed in the Shorts feed over 90 " +
        "days. Uploads: valid public long-form videos posted in the last 90 days. Zero active " +
        "Community Guidelines strikes, 2-Step Verification switched on, and a linked AdSense " +
        "account complete the checklist. Figures here are API-derived and close to — but not " +
        "identical to — YouTube Studio's Earn tab.";
    /// <summary>Account sign-in/out changed (fires from MainViewModel): reset the
    /// signed-out state and refresh when a session now exists.</summary>
    public void OnAccountChanged()
    {
        OnPropertyChanged(nameof(IsSignedOut));
        OnPropertyChanged(nameof(DisplayName));
        if (_hasSnapshot && !_isConnected())
        {
            _hasSnapshot = false;
            OnPropertyChanged(nameof(HasSnapshot));
        }
        if (_isConnected())
            _ = EnsureLoadedAsync();
    }
    /// <summary>Loads once per session/day (quota-honest: the analytics slice that
    /// gives watch-hours/shorts has a thin targeted-query budget, so this gate is
    /// baked in now). A manual "Refresh" always goes to the wire.</summary>
    public async Task EnsureLoadedAsync()
    {
        if (!_isConnected() || _hasSnapshot) return;
        var last = _store().LoadYppLastRefreshedAtUtc();
        if (last != null && DateTime.UtcNow - last.Value < TimeSpan.FromHours(24)) return;
        await RefreshAsync();
    }
    public async Task RefreshAsync()
    {
        if (_isRefreshing) return;
        _isRefreshing = true;
        IsLoading = true;
        LoadError = null;
        try
        {
            if (!_isConnected())
            {
                _lastRefreshedAtUtc = null;
                OnPropertyChanged(nameof(LastUpdatedText));
                return;
            }
            var snapshot = await _stats().CaptureCurrentAsync();
            if (snapshot == null)
            {
                LoadError = "Couldn't reach YouTube — try again.";
                return;
            }
            ApplySnapshot(snapshot);
            _store().SaveYppSnapshot(snapshot);
            _lastRefreshedAtUtc = snapshot.CapturedAtUtc;
            _store().SaveYppLastRefreshedAtUtc(snapshot.CapturedAtUtc);
            OnPropertyChanged(nameof(LastUpdatedText));
        }
        catch (Exception ex)
        {
            AppLog.Write($"YPP refresh failed: {ex}");
            LoadError = "Refresh failed — try again.";
        }
        finally
        {
            _isRefreshing = false;
            IsLoading = false;
        }
    }
    private void ApplySnapshot(YppStatSnapshot snapshot)
    {
        _displayNameText = _displayName() ?? string.Empty;
        _subscriberCount = snapshot.SubscriberCount;
        _videoCount = snapshot.VideoCount;
        _totalViews = snapshot.TotalViews;
        _uploadsLast90Days = snapshot.UploadsLast90Days;
        _hasSnapshot = true;
        OnPropertyChanged(nameof(DisplayName));
        OnPropertyChanged(nameof(SubscriberCount));
        OnPropertyChanged(nameof(VideoCount));
        OnPropertyChanged(nameof(TotalViews));
        OnPropertyChanged(nameof(UploadsLast90Days));
        OnPropertyChanged(nameof(HasSnapshot));
        OnPropertyChanged(nameof(Tier1SubsProgress));
        OnPropertyChanged(nameof(Tier2SubsProgress));
        OnPropertyChanged(nameof(UploadsProgress));
        OnPropertyChanged(nameof(Tier1SubsBarWidth));
        OnPropertyChanged(nameof(Tier2SubsBarWidth));
        OnPropertyChanged(nameof(UploadsBarWidth));
        OnPropertyChanged(nameof(Tier1SubsText));
        OnPropertyChanged(nameof(Tier2SubsText));
        OnPropertyChanged(nameof(UploadsText));
        OnPropertyChanged(nameof(StandingDetailText));
    }
    private void PersistChecklist() => _store().SaveYppChecklist(TwoFactorEnabled, AdSenseLinked);
    private static double Progress(long current, long target)
        => target <= 0 ? 0 : Math.Clamp((double)current / target, 0, 1);
    private static void OpenUrl(string url)
    {
        Process.Start(new ProcessStartInfo(url) { UseShellExecute = true });
    }
 }
@@ -6,10 +6,15 @@ External-facing logic: YouTube API, persistence. See
 | File | Purpose |
 |------|---------|
 | `YouTubeAuthService.cs` | OAuth2 via Google: loopback callback (`http://localhost:8765/oauth2/callback`), token exchange, refresh, channel fetch. Constructor takes optional `HttpClient` + `sessionChanged` callback (test seam + save hook); session persists via `Helpers/TokenStore` (DPAPI); `ClearSession()` signs out (called by `MainViewModel.StopStream` on End Livestream) |
-| `YouTubeStreamService.cs` | Broadcast/stream management via the v3 API. **`CreateBroadcast` always sends `privacyStatus = "private"`** (ship step 7 — private-only until v1) and the one-click v3 flags (`enableAutoStart/Stop`, `enableMonitorStream=false`, `latencyPreference=low`); injectable `HttpClient? http = null` ctor seam so tests can fake the API. **`GetOrCreateReusableStreamAsync` (TASK 9, shipped 2026-08-16)** returns the channel's `ReusableStream` — lists `liveStreams?mine=true` and reuses the existing `cdn.isReusable` stream, inserting once only on first use (`resolution=variable`, `frameRate=variable`, `isReusable=true`); a stream id given to `CreateBroadcast` binds at insert via `contentDetails.boundStreamId`. RTMP URL = `ingestionAddress + "/" + streamName`. **`GetStreamHealthAsync(streamId)` (TASK 9 item 3, shipped 2026-08-16)** polls `liveStreams?part=status` → `StreamHealth` with parsed `configurationIssues[]` |
+| `YouTubeStreamService.cs` | Broadcast/stream management via the v3 API. **`CreateBroadcast` always sends `privacyStatus = "private"`** (ship step 7 — private-only until v1) and the one-click v3 flags (`enableAutoStart/Stop`, `enableMonitorStream=false`, `latencyPreference=low`); injectable `HttpClient? http = null` ctor seam so tests can fake the API. **`GetOrCreateReusableStreamAsync` (TASK 9, shipped 2026-08-16)** returns the channel's `ReusableStream` — lists `liveStreams?mine=true` and reuses the existing `cdn.isReusable` stream, inserting once only on first use (`resolution=variable`, `frameRate=variable`, `isReusable=true`); a stream id given to `CreateBroadcast` binds at insert via `contentDetails.boundStreamId`. RTMP URL = `ingestionAddress + "/" + streamName`. **`GetStreamHealthAsync(streamId)` (TASK 9 item 3, shipped 2026-08-16)** polls `liveStreams?part=status` → `StreamHealth` with parsed `configurationIssues[]` (NOTE 2026-09-22: the real API nests `status.healthStatus = {status, lastUpdateTimeSeconds, configurationIssues[]}` as an OBJECT — the parse reads the nested `.status` and tolerates the old flat-string shape; the object shape used to crash every poll) | **`EndBroadcastAsync` (2026-09-01; hardened 2026-09-22)** posts `liveBroadcasts/transition?broadcastStatus=complete&part=status` AFTER RTMP EOF with a pre-flight `liveBroadcasts.list` read of the broadcast's OWN `lifeCycleStatus`: only transitions from `live`/`testing`, skips already-complete broadcasts silently (2026-09-22: every blind end logged `invalidTransition` — autoStop races us to complete); `enableAutoStop` finishes every skip |
 | `StreamHealthReporter.cs` | Pure report-by-exception decision (TASK 9 item 3): `BannerFor(issues)` → `HealthIssueReport(Text?, IsError)` — null text on good/ok/noData/info-only, first warning/error issue produces its type text, error beats warning for color |
-| `YouTubeChatService.cs` | Polls `liveChat/messages`, raises `MessageReceived`; `IDisposable` |
+| `YouTubeChatService.cs` | Polls `liveChat/messages`, raises `MessageReceived`; `IDisposable`. **TASK 43 rewrite (2026-09-24):** re-arms its one-shot poll on the server's `pollingIntervalMillis` (streamList semantics — reconnect on that cadence with `nextPageToken`, clamp 1000–6000ms, `maxResults=2000`); `ParsePage` (internal static seam) decodes **all six** event types into `ChatMessage.Kind`/fields (superChat / superSticker / newSponsor / membershipGifting / giftMembershipReceived / memberMilestoneChat + milestone months best-effort regex); optional `HttpClient` ctor seam endures; `InjectSimulatedMessage` (TASK 41) preserved |
-| `LayoutStore.cs` | SQLite persistence (`Microsoft.Data.Sqlite`) at `%APPDATA%\ytLlive\ytLlive.db`; assets stored as BLOBs keyed by SHA-256 content hash; save/open layout files; schema `user_version` 6 (`Source.ClipShape`/`IsMirrored` via `ALTER TABLE` for pre-v2 DBs; v3 = singleton `Webcam` + per-scene `WebcamSceneConfig`, migrated idempotently **without backfill** — the stale `Source.DeviceId` column remains but is no longer read/written; v4 = `WebcamSceneConfig.RectWidth`/`RectHeight`, the pre-Round rect for the round-to-rect restore; v5 = `Source.IsBackdrop` + `Source.CaptureKey`, the live-capture backdrop; v6 = `Scene.HasBackdrop` — Live-only policy, one-time backfill turns Starting/BRB/Chat/Ending off + drops their backdrop sources; `MainViewModel.NormalizeBackgrounds` re-normalizes on every load — TASK 25: one locked "Background" per canonical screen (static art everywhere, DisplayCapture on Live), duplicates dropped, index 0, orphaned `BackgroundUseDefault_*`/`BackgroundPath_*` Settings keys purged at save). Settings key/value table holds app state: `MicSourceName`, `ReusableStream` (TASK 9 — the cached reusable stream's id/address/name so the pump has its RTMP URL at startup) |
+| `ChatBoxRenderer.cs` | Chat overlay rasterizer (WPF FormattedText → BGRA `VideoFrame`), live rows + Super Chat/member styling |
 | `ChatOverlayLayer.cs` | **The chat component (Commit G):** owns the message buffer, `ChatBoxRenderer`, fade/mock timers, per-source preview renders, live `RenderFrame`; raster-on-change cache pattern (OBS text-source contract) |
 | `AlertRenderer.cs` | **The alert rasterizer (TASK 43, 2026-09-24):** renders one event's celebration animation into a BGRA `VideoFrame` — SIX DISTINCT animations (SuperChat slide-up/shine/count-up, SuperSticker scale-pop, NewMember drop-in/flash-band, MemberGift slide-left/chip-fan, GiftReceived confetti scale-in, MemberMilestone rise/growth-bar), enter/hold/exit phases, brand line on every card. **Still the fallback** when no alert clip is playable (TASK 47) |
 | `AlertOverlayLayer.cs` | **The native alert-box component (TASK 43; video branch TASK 47):** event queue (cap 10) + 33ms dispatch ticker + `RenderFrame` cache-first live path + `UpdatePreview`; **`Advance(double)` is the deterministic test clock** (tests never start the timer); `ChatEventKind.None` rows (sub mentions) never enqueue; idle = transparent (null frame). Since TASK 47 a clip branch owns `IAlertClipDecoder` per play — ctor seams `(clipDecoderFactory, clipPathResolver, audioSink)`, fade in/out over `FadeDurationSeconds = 0.30` (straight-alpha copies + volume×fade audio), EOF freeze-frame → drain, and `AlertTickerFrame` composes the scrolling message strip |
 | `AlertClipDecoder.cs` | **Per-play alert video decoder (TASK 47):** `IAlertClipDecoder` (Start/Stop/Dispose + `FrameAvailable`/`AudioReady`/`Completed`) + ffmpeg child emitting `rawvideo bgra` (`-vf scale=W:H`, read via `RawVideoFrameReader`) and `f32le -ar 48000 -ac 2` on a **carry-buffer** audio loop (float boundary straddles never drop samples), both real-time paced; bgra is opaque (layer owns alpha). One-shot lifetime — created per alert, disposed at drain; tests inject a fake |
 | `LayoutStore.cs` | SQLite persistence (`Microsoft.Data.Sqlite`) at `%APPDATA%\ytLlive\ytLlive.db`; assets stored as BLOBs keyed by SHA-256 content hash; save/open layout files; schema `user_version` 10 (`Source.ClipShape`/`IsMirrored` via `ALTER TABLE` for pre-v2 DBs; v3 = singleton `Webcam` + per-scene `WebcamSceneConfig`, migrated idempotently **without backfill** — the stale `Source.DeviceId` column remains but is no longer read/written; v4 = `WebcamSceneConfig.RectWidth`/`RectHeight`, the pre-Round rect for the round-to-rect restore; v5 = `Source.IsBackdrop` + `Source.CaptureKey`, the live-capture backdrop; v6 = `Scene.HasBackdrop` — Live-only policy, one-time backfill turns Starting/BRB/Chat/Ending off + drops their backdrop sources; v9→v10 (TASK 39) = `YppSnapshot` history table; all later columns stay additive guarded ALTERs — TASK 47 adds the five alert `Source` columns (`AlertVideoAssetId`/`AlertVideoPath`/`AlertUseDefaultVideo`/`AlertShowTicker`/`AlertVideoVolume`) without a version bump; `MainViewModel.NormalizeBackgrounds` re-normalizes on every load — TASK 25: one locked "Background" per canonical screen (static art everywhere, DisplayCapture on Live), duplicates dropped, index 0, orphaned `BackgroundUseDefault_*`/`BackgroundPath_*` Settings keys purged at save). Settings key/value table holds app state: `MicSourceName`, `ReusableStream` (TASK 9 — the cached reusable stream's id/address/name so the pump has its RTMP URL at startup), `AlertDefaultVideoAssetId` (TASK 47 — the stamped built-in alert clip's asset row; save's prune exempts it via UNION) |
 | `VideoFrame.cs` | Normalized CPU frame seam (`Width`/`Height`/tightly-packed BGRA `byte[]`) — the only pixel type the rest of the app knows about; future capture sources (screen, background-removed webcam) feed the same seam |
 | `CameraDeviceInfo.cs` | `(Id, DisplayName)` for a physical capture device |
 | `ICameraEnumerator.cs` | `GetCamerasAsync()` — seam so the picker/`CameraManager` never touch WinRT (tests inject fakes) |
@@ -28,13 +33,16 @@ External-facing logic: YouTube API, persistence. See
 | `ScreenCaptureFrameSource.cs` | One `Direct3D11CaptureFramePool` (free-threaded, 2 buffers) + session per target; frames → `SoftwareBitmap.CreateCopyFromSurfaceAsync` (BGRA, alpha ignored) → `VideoFrame`, bytes read via `WindowsRuntimeMarshal.TryGetDataUnsafe` (CsWinRT-safe — the `IMemoryBufferByteAccess` ComImport cast fails on every frame and is gone). Surfaces > 1920×1080 downscaled bilinearly to the master; conversion failures logged ≤ once/5 s. DRM content = black frames (OS limit). `CreateForMonitor`/`CreateForWindow`/`CreateForPicker` |
 | `ScreenCaptureManager.cs` | Screen-capture ownership mirroring `CameraManager`: refcounted by target key, one shared `WriteableBitmap`, dispatcher-coalesced latest-frame copies; `PreviewBitmapChanged`/`CaptureFailed` events; `ReleaseAllAsync` used on re-designation |
 | `ScreenCaptureSourceFactory.cs` | `Resolve(key)` parses `monitor:<n>` / `window:<hwnd>` / `picker:<name>` into a source; `PickAsync()` shows the OS `GraphicsCapturePicker` and returns the `picker:` key (transient — a reload falls back to auto-detection) |
-| `Compositor/SceneCompositor.cs` | **The output compositor (TASK 4 ship step 1)**: renders a scene into the encoder's master `VideoFrame` (tightly-packed BGRA8), mirroring the XAML preview minus editing chrome — backdrop → background → elements (`UniformToFill` cover-crop, round clip, mirror, opacity, border) → branding flash → social bar (optional `socialBarFrame` + `socialBarTop` in master space, blitted last so the bar sits above the flash; the old `BlitFlash` generalized to `BlitOverlay` with source offsets). Pure and WPF-free: frames injected via a `Func<SceneElement, VideoFrame?>` resolver (webcam → DeviceId, image → AssetId, backdrop → CaptureKey); output sized by `CompositorOptions` (16:9 = full master 1:1; vertical 9:16 = 607×1080 crop → 1080×1920 bilinear). Preview stays XAML (editing view); this is the output view — see `ai.md` "Scene compositor" |
+| `WebView2Manager.cs` | **Web-source ownership (TASK 17, composition-capture since 2026-09-14):** per registered `Source { Type: WebSource }` it owns a `CoreWebView2CompositionController` + its visual tree (`RootVisualTarget` child under a 1920×1080 root `ContainerVisual` on one `Windows.UI.Composition.Compositor` created on the UI thread via the CoreMessaging `CreateDispatcherQueueController` P/Invoke), a wrapped `WebCaptureFrameSource`, and the shared crop-sized `WriteableBitmap` preview (dispatcher-coalesced copy at Render priority, `PreviewBitmapChanged` raised only on recreation). Nav + `TransparentBackgroundScript` injection unchanged. Public ctor `(Dispatcher)`; internal seam ctor `(Dispatcher, Func<string, IScreenCaptureSource>?)` for hermetic tests (no WinRT). Caller: `MainViewModel.InitWebView2()` (now invoked from `MainWindow_Loaded` — the parent HWND must exist). See `../ai.md` "Slice 14" |
 | `WebCaptureFrameSource.cs` | The `IScreenCaptureSource` for a web session: owns the `GraphicsCaptureItem` (`CreateFromVisual`) + a free-threaded `Direct3D11CaptureFramePool` (2 buffers) + session; readback via `SoftwareBitmap.CreateCopyFromSurfaceAsync` (BGRA, **`BitmapAlphaMode.Straight`** — the compositor blends straight alpha); per-frame `FindContentBounds` alpha-bbox (internal static, unit-tested) stamps `VideoFrame.CropBounds`; ring up to 2 fresh frames + Epoch reuse; `IsOpaque=false`. Mirror of `ScreenCaptureFrameSource` |
 | `Compositor/SceneCompositor.cs` | **The output compositor (TASK 4 ship step 1)**: renders a scene into the encoder's master `VideoFrame` (tightly-packed BGRA8), mirroring the XAML preview minus editing chrome — backdrop → background → elements (`UniformToFill` cover-crop, round clip, mirror, opacity, border) → branding flash → social bar (optional `socialBarFrame` + `socialBarTop` in master space, blitted last so the bar sits above the flash; the old `BlitFlash` generalized to `BlitOverlay` with source offsets). **TASK 47:** `Render` + `CompositeLayers` take a trailing `tickerFrame` blitted at (0,0) after the bar — the alert ticker is a message-scrolling dynamic overlay, never baked. Pure and WPF-free: frames injected via a `Func<SceneElement, VideoFrame?>` resolver (webcam → DeviceId, image → AssetId, backdrop → CaptureKey); output sized by `CompositorOptions` (16:9 = full master 1:1; vertical 9:16 = 607×1080 crop → 1080×1920 bilinear). Preview stays XAML (editing view); this is the output view — see `ai.md` "Scene compositor" |
 | `Compositor/CompositorOptions.cs` | The active tier's output rect (source space over the 1920×1080 master, integer-aligned — `MainViewModel.OutputRectX` can be 656.5) + target W×H |
 | `Compositor/StretchMath.cs` | Pure pixel math: the WPF `UniformToFill` cover-crop, clamped bilinear sample/scale (unit-tested half of the compositor) |
 | `Compositor/StaticPixelCache.cs` | Asset bytes → cached BGRA8 `VideoFrame`, decoded once per content hash — the output path's raw-pixel source (the preview uses ImageCache's `BitmapImage`) |
 | `Encoder/IFfmpegLocator.cs` | **TASK 4 ship step 2 seam**: resolves an absolute path to `ffmpeg.exe` (PATH first → cached `%APPDATA%\ytLlive\tools\ffmpeg.exe` → pinned BtbN LGPL-shared zip download). The encoder step and tests fake it |
 | `SocialValidator.cs` | `ISocialValidator` seam + `HttpSocialValidator` default: validates a social handle/URL by constructing the canonical profile URL and issuing an HTTP GET — the "act of validation" before adding to the bar. 200/redirect = exists; 404/connection failure = rejected. Fediverse `@user@domain` additionally does a best-effort nodeinfo lookup (`/.well-known/nodeinfo` → `software.name`) so the entry can show the instance's real logo; nodeinfo failure still validates (generic fediverse glyph). If the identity domain's nodeinfo is blocked (SSO) but the bare root 302s to the real instance (YunoHost default-app subdomains), the lookup follows the redirect and asks that host. Since the bar bug-fix branch the resolution **probes well-known subdomains** (`mastodon.`, `social.`, ... order in `FediverseSubdomainCandidates`) when both the identity domain and its redirect come up empty, bounded by a ~15s linked-CTS budget; `ResolveFediverseSoftwareAsync(domain, ct)` on the seam powers the load-time heal. Constructor takes optional `HttpClient` + `Action<string>` log for tests |
 | `Compositor/SocialBarRenderer.cs` | **Social bar output strip** (bar bug-fix branch): rasterizes the global social bar into a transparent straight-alpha BGRA8 `VideoFrame` strip (1920 wide, 40px content + 24px glow pad) via `RenderTargetBitmap` — one Path (logo) + one TextBlock (handle) per entry, white on transparent with the preview's green `#2ecc71` glow baked in (Pbgra32 → straight-alpha unpremultiply). UI thread only; the frame is immutable afterwards so the `FramePump` reads it from its own thread |
 | `Compositor/AlertTickerRenderer.cs` | **Alert message ticker strip (TASK 47):** marquee overlay rendered per call by pure byte-math onto a 1920×48 transparent BGRA frame — the text pill ("Author — Kind · amount") is rasterized once per text on the UI thread (cached, unpremultiplied straight alpha) and scrolled at 140px/s with a repeat-gap wrap, so the pump can call `Render(elapsed, text)` from its own thread without locking. **Dynamic overlay — never baked** (unlike the social bar) |
 | `Encoder/EncoderOptions.cs` | One go-live's encoder config: full `RtmpUrl` (ingest + stream key), W×H/FPS/bitrate from the quality tier, `VideoEncoder` (null = probe), audio sample rate/channels, `GopSize` = FPS×4 (the ≤4s keyframe bound) |
 | `Encoder/IFfmpegEncoder.cs` | **TASK 4 ship step 3 seam**: start/feed/stop the live encoder; `HealthUpdated` (parsed `StreamHealth`), `ProcessFailed` on unexpected non-zero exit. Constructor-injected locator + process factory (tests fake both) |
 | `Encoder/FfmpegEncoder.cs` | The default encoder: spawn `ffmpeg.exe` (probe `-encoders` first → hardware NVENC/QSV/AMF, OpenH264 fallback — never libx264), feed raw BGRA frames into stdin, parse `-stats` lines into `StreamHealth`, graceful stop via stdin EOF + 10s kill watchdog. Constructed by `MainViewModel` since ship step 5 (`new FfmpegEncoder(new FfmpegLocator())`), driven by the `FramePump` |
@@ -43,7 +51,7 @@ External-facing logic: YouTube API, persistence. See
 | `Encoder/FfmpegArgs.cs` | Pure FFmpeg command-line builder: rawvideo `pipe:0` input, `anullsrc` silent audio (WASAPI replaces it), H.264+AAC, closed GOP (`-g fps×4 -keyint_min -sc_threshold 0 -bf 0`, `yuv420p`), FLV → RTMP |
 | `Encoder/FfmpegProgressParser.cs` | Pure parser for `frame=/fps=/size=/time=/bitrate=` stats lines → `FfmpegProgress` |
 | `Encoder/FfmpegEncoderPicker.cs` | Pure H.264 encoder picker from `-encoders` output: NVENC → QSV → AMF → OpenH264; **never returns libx264** (GPL) |
-| `Encoder/FramePump.cs` | **TASK 4 ship step 5**: the live frame producer — while live it snapshots the active scene each tick, resolves every element to its latest frame (`Func<SceneElement, VideoFrame?>` resolver), composites it into the tier's output frame, and paces frames into the encoder at the tier's FPS. All collaborators constructor-injected seams; free of WPF and the capture managers. `StartAsync` never throws (failures log + `Failed`); no RTMP URL = encoder skipped; `StopAsync` stops the encoder before awaiting the loop (backpressure deadlock); `ProcessFailed` self-stops. Since the bar bug-fix branch it takes an optional `socialBar: Func<(VideoFrame? Frame, SocialBarPosition Position)>?` seam — a pre-rendered bar strip composited last (above the flash) at the top edge or `SourceRectHeight − bar height`. See `ai.md` "Live frame pipeline" |
+| `Encoder/FramePump.cs` | **TASK 4 ship step 5**: the live frame producer — while live it snapshots the active scene each tick, resolves every element to its latest frame (`Func<SceneElement, VideoFrame?>` resolver), composites it into the tier's output frame, and paces frames into the encoder at the tier's FPS. All collaborators constructor-injected seams; free of WPF and the capture managers. `StartAsync` never throws (failures log + `Failed`); no RTMP URL = encoder skipped; `StopAsync` stops the encoder before awaiting the loop (backpressure deadlock); `ProcessFailed` self-stops. Since the bar bug-fix branch it takes an optional `socialBar: Func<(VideoFrame? Frame, SocialBarPosition Position)>?` seam — a pre-rendered bar strip composited last (above the flash) at the top edge or `SourceRectHeight − bar height`. **TASK 47:** adds an `alertTicker: Func<VideoFrame?>?` ctor seam (parallel to `socialBar`), read per tick and threaded through `RenderScene`/`RenderFull` + **mixed into `BuildFullRenderSignature`** so the ticker scroll changes the cache key. See `ai.md` "Live frame pipeline" |
 | `Encoder/FfmpegLocator.cs` | The default locator: PATH probe wins, then the cache, then pull+extract (`ffmpeg.exe` **+ the `libav*.dll` family** via a staging dir, failures via `AppLog`). Pinned to BtbN `autobuild-2026-08-09-13-03` **lgpl-shared** (dynamic linking = LGPL compliance without static-relink §6 material; no GPL libx264; NVENC/QSV/AMF + libopenh264 + native AAC — see `ai.md` → Licensing). Search dirs / tools dir / downloader constructor-injected for hermetic tests. Wired into the encoder since ship step 5 |
 | `INotificationService.cs` | **Toast seam (TASK 24)**: `Show(title, message, AppNotificationSeverity)` + `AppNotificationSeverity { Info, Success, Warning, Error }` + `Info/Success/Warning/Error` extension methods — non-blocking user-facing messages; VMs/services raise through this so failures surface without MessageBox blocking the UI thread |
 | `NotificationService.cs` | The default seam impl (Notification.Wpf 11.0.0, MIT): wraps a library `NotificationManager`; routes to the in-window `NotificationArea` named `ToastArea` (MainWindow bottom-right above the footer); lifetimes via the pure `BuildRequest` mapping + `Cards` tint table — Info/Success ~4s, Warning ~8s auto-dismiss, Error sticky (`NeverExpires()` = `TimeSpan.MaxValue`, never null); dark card tints matching the health-banner language; all Show calls marshal to the captured Dispatcher. See [`../ai.md`](../ai.md) "Toast notifications" |
@@ -51,7 +59,7 @@ External-facing logic: YouTube API, persistence. See
 | `Audio/AudioSample.cs` | One captured chunk: interleaved PCM float (-1..1) + sample rate + channels |
 | `Audio/WasapiLoopbackAudioSource.cs` | Desktop/game capture: NAudio `WasapiLoopbackCapture` on the default render device — automatic at unity; the game bar's meter consumes it |
 | `Audio/WasapiMicAudioSource.cs` | Mic capture: NAudio `WasapiCapture` with the device resolved by `FriendlyName` matching `MicSourceName` (DisplayName only), default capture endpoint fallback; name provider `Func<string?>` re-read at each `Start` so a device picked mid-session takes effect immediately (the mixer restarts the mic on pick) |
-| `Audio/AudioMixer.cs` | Owns both sources; capture starts once at startup (`MainViewModel.StartMicCaptureAsync`) and stops on `Shutdown` — NOT go-live (preview monitoring). Mic samples → `AudioLevelMeter` → `MicLevelChanged`; loopback samples → the game bar's meter via `LoopbackLevelChanged`. Surfaces mic connection state: `MicConnected`/`MicFailed` (drives the status dot) + `RestartMic()` (device swap mid-session, keeps loopback). Failures log via `AppLog`; mic failure zeroes the meter, loopback failure doesn't kill the mic. Note: the meter `Push` is unconditional (the `?.` on the event would otherwise skip the argument when nothing is subscribed) |
+| `Audio/AudioMixer.cs` | Owns both sources; capture starts once at startup (`MainViewModel.StartMicCaptureAsync`) and stops on `Shutdown` — NOT go-live (preview monitoring). Mic samples → `AudioLevelMeter` → `MicLevelChanged`; loopback samples → the game bar's meter via `LoopbackLevelChanged`. Surfaces mic connection state: `MicConnected`/`MicFailed` (drives the status dot) + `RestartMic()` (device swap mid-session, keeps loopback). Failures log via `AppLog`; mic failure zeroes the meter, loopback failure doesn't kill the mic. Note: the meter `Push` is unconditional (the `?.` on the event would otherwise skip the argument when nothing is subscribed). **TASK 47 — alert audio:** `EnqueueAlertAudio` writes a dedicated 8s stereo-48k ring (`AlertBufferSeconds`), drained in `FillAndMix` pre-limiter and added at **unity (never ducked)**; `StartLive` clears the ring |
 | `Audio/AudioLevelMeter.cs` | Pure smoothed RMS level (0..1): `Push(AudioSample)` + `Reset` — the unit-tested math behind `AudioLevel` and `GameAudioLevel`. `ToDisplay(float)` maps the raw linear RMS onto the meter's display scale (−60..0 dBFS spread across 0..1, with **+10 dB input amplification** so real speech peaks hit the red zone at maxed volume) — real speech/game RMS (~0.01..0.1) would otherwise leave a flat scale looking dead; ≤0.001 linear reads as zero (never idles on background noise) |
 | `Audio/WaveToFloat.cs` | Pure WASAPI buffer → float conversion: IEEE float 32-bit direct, PCM 16-bit normalized, `WaveFormatExtensible` IEEE-float subformat GUID, trailing partial samples ignored |
 | `Audio/MasterLimiter.cs` | **Master output limiter**: a **−1 dBFS ceiling** (`Ceiling = 0.891`) applied after the live mix so the honest gains can never sum past 0 dBFS and clip the AAC encode. Instant attack per frame (a hot frame is scaled exactly to the ceiling — no overshoot), smoothed release toward unity so loud passages don't pump. Pure — unit-tested |
@@ -0,0 +1,461 @@
 # ytLlive — Windows Store & code-signing certification research (authoritative)
 > Catalog: [`TASKS.md`](../TASKS.md) · memory map: [`schema.md`](../schema.md) · distribution plan: [`Distribution.md`](../Distribution.md)
 >
 > **Researched 2026-09-27** against **Microsoft Store Policies version 7.20** (published
 > 2026-09-15, effective 2026-10-22) and the MSIX packaging docs. Policy version moves —
 > re-check the version before acting on any line here.
 >
 > **This file is the "why".** The executable checklist lives in
 > [`task-48-distribution-msix.md`](task-48-distribution-msix.md). No code changed as a
 > result of this research; it only decides what task-48 will eventually do.
 ---
 ## 1. Bottom line
 **✅ ROUTE DECIDED 2026-09-27 — the creator chose route A: Microsoft Store, MSIX package,
 Store IAP.** The research below is what the decision was made from, and it stays as the
 audit trail so the choice is never re-litigated. The executable checklist is
 `TASKS/task-48-distribution-msix.md`; the ruling and the criteria behind it are in that
 file's item 0.
 **MSIX packaging is viable.** One real blocker, and it is a code change we should want
 anyway (§4). Three technical blockers that normally kill a Store submission — drivers,
 per-user services, elevation — we **do not trip** (§7).
 **Nothing else is open on distribution.** The only number still unverified is the Store
 revenue-share rate (§11 item 4), which is a *pricing* input, not a distribution one.
 ---
 ## 2. ⚠️ The one line in `Distribution.md` that is now wrong
 `Distribution.md:318` currently says:
 > Buy an EV (Extended Validation) code-signing certificate from DigiCert or Sectigo
 > ($200-400/year). EV certificates get instant SmartScreen reputation; DV/OV certs
 > trigger SmartScreen warnings for months.
 **The EV half of that is false.** Microsoft removed the SmartScreen instant-bypass for EV
 certificates in **March 2024**. An EV-signed file now accumulates reputation exactly the
 way an OV-signed file does. Paying $400+/yr buys precisely what paying $150 buys.
 `schema.md` rule 4: stale facts get FIXED, not appended. Corrected in `Distribution.md`
 (2026-09-27).
 Also worth knowing before budgeting:
 - **Cert validity is capped at 460 days** (CA/B Forum CSC-31, effective 2026-03-01). This
  is a recurring annual line item, not a one-time purchase.
 - **Private keys must live on an HSM or hardware token** (CA/B rule since 2023-05). Budget
  for the token or a cloud HSM.
 - **Signing does not clear the warning on day one.** A valid cert stops the *malware*
  warning immediately; the "unrecognized publisher" warning clears as SmartScreen accrues
  reputation from real download volume. Expect a ramp on every route.
 - **Third-party AV vendors layer their own reputation blocking on top of SmartScreen**, so
  signed-but-new can still warn on consumer machines. The Store route is the only one that
  is warning-free, because Microsoft holds the reputation.
 ---
 ## 3. Signing economics
 | Route | Cert cost | SmartScreen | Install UX | Notes |
 |---|---|---|---|---|
 | **Microsoft Store, MSIX package** | **$0** — Microsoft re-signs | No warning | Normal | Store review, public listing, updates handled by Store |
 | **Microsoft Store, EXE/MSI (10.2.9)** | **$150–300/yr — your own cert** | Warning ramp | **Silent install only** | Store does NOT re-sign; you maintain a versioned URL |
 | **Direct + OV cert** | $150–300/yr | Warning ramp | Yours | Worldwide availability |
 | **Direct + Azure Artifact Signing** | ~$9.99/mo ≈ $120/yr | Warning ramp | Yours | **Individuals: USA/Canada only.** Identity validation required |
 | **Direct + EV cert** | $400+/yr | Same as OV | Yours | **Do not buy.** No benefit since March 2024 |
 | **Unsigned direct** | $0 | Strong block | Yours | Unusable for public download |
 ### Four real combinations
 | # | Distribute | Verify payment | Cert | Revenue cut |
 |---|---|---|---|---|
 | **A** | Store | Store IAP | $0 | yes |
 | **B** | Store | **Polar** | $0 | no |
 | **C** | Polar file hosting | Polar | $150–300/yr | no |
 | **D** | Store EXE (10.2.9) | Polar | $150–300/yr | no |
 **✅ A was chosen (2026-09-27)** — the creator's criteria were "zero headaches, minimal
 maintenance (for me) while still providing accountability and a reasonably easy upgrade
 flow," and A is the only option where *every* one of those is solved by handing the work to
 Microsoft rather than to a certificate vendor. The rest of this section stays as the record
 of what was rejected and why, so the decision is not reopened by a later session that
 remembers only that "certs cost $150/yr."
 **A** is the only one where Polar becomes unnecessary — the Store handles payment,
 entitlement, and refunds, and `PolarLicenseService` and the customer-portal plumbing are
 deleted. That is a *distribution* choice that happens to subsume licensing.
 **B** is the compromise that was **not** taken: the Store would have solved the SmartScreen
 problem and the annual cert bill while Polar stayed the licensing system. Rejected because
 it keeps a licensing backend, a customer portal, activation limits, and an offline-grace
 machine alive — the exact maintenance the ruling was made to eliminate.
 **C** is the status quo previously sketched in `Distribution.md:14` / `:296` — Polar hosts
 the signed exe (10GB, signed personal download URLs, SHA-256 included). **The Store is not
 needed for delivery at all**; its only unique value is *free Microsoft signing with no
 SmartScreen warning*, and its cost is MSIX packaging work, Store review, and a public
 listing. Note the irony: C is the only option with a recurring cost *and* the only one where
 the creator maintains payment plumbing themselves.
 **D is dominated** — strictly worse than both A and C: cert required anyway, silent install
 required, and we maintain the versioned download URL. Documented in one line so it is
 never re-litigated.
 ---
 ## 4. ⛔ The one real blocker: 10.2.2 (dynamic code inclusion)
 **Policy 10.2.2:**
 > Your product must not attempt to fundamentally change or extend its described
 > functionality or introduce features or functionality that is in violation of Store
 > Policies **through any form of dynamic inclusion of code**. Your product should not, for
 > example, **download a remote script and subsequently execute that script** in a manner
 > that is not consistent with the described functionality.
 **What we do today:** `Services/Encoder/FfmpegLocator.cs:37-38` pins a GitHub release URL,
 and `LocateAsync` downloads the zip (line 69), extracts it (line 73), and the encoder then
 executes that binary. On a cold cache the app **downloads an unsigned executable from the
 internet and runs it.**
 That is the pattern 10.2.2 names. The word is "script," so a narrow reviewer might quibble
 about a PE binary — but 10.2.3 reinforces it, and 10.2.9 separately requires all PE files
 to chain to the Microsoft Trusted Root Program, which a downloaded BtbN build does not.
 **The fix:** bundle `ffmpeg.exe` + `ffprobe.exe` + the `libav*.dll` family **inside the
 package** instead of downloading. No dynamic code inclusion, so 10.2.2 is satisfied.
 **This is a fix we want regardless of route.** `FfmpegLocator.cs:30-35` records that the
 previous daily pin aged out of GitHub retention and **404'd on the first real recording
 attempt (2026-09-01)**. Bundling kills that entire class of cold-start failure permanently,
 and it also removes the startup network dependency.
 The LGPL-shared licensing reasoning in `FfmpegLocator` is unaffected — dynamic linking was
 the deliberate choice for LGPL §6 compliance, not for download avoidance. Confirm
 `THIRD-PARTY-NOTICES.txt` (already shipped) covers the bundled build.
 **What I got wrong initially:** I believed MSIX might forbid *launching* a bundled
 executable. It does not — see §5.
 ---
 ## 5. MSIX technical facts (full trust vs AppContainer)
 MSIX packages run at one of two trust levels, chosen by the manifest:
 | Trust level | Behavior |
 |---|---|
 | **`mediumIL` / full trust** | **Same permissions as a standard desktop app.** Package identity + some file/registry virtualization. **Can spawn child processes.** ← this is what a WPF broadcast tool wants |
 | `appContainer` | Strictly isolated. Process and children see only explicitly granted resources. File/registry virtualized. |
 **A packaged WPF app declaring `runFullTrust` runs at medium integrity — it is not an
 AppContainer.** Bundling and launching ffmpeg from inside the package is therefore fine.
 This is the "Desktop Bridge" / `packagedClassicApp` model.
 **Critical file-write consequence:** "Writes to user profile locations (such as AppData) are
 redirected to per-package locations for AppContainer apps, or **pass through for full-trust
 apps**." The package install folder itself is read-only.
 **Manifest this app needs:**
 - `rescap:Capability Name="runFullTrust"` — medium integrity
 - `webcam` and `microphone` capabilities
 - `uap10:TrustLevel="mediumIL"`
 - `uap10:RuntimeBehavior="packagedClassicApp"`
 ### The full-trust recording invariant (durable architectural fact)
 `ViewModels/MainViewModel.Recording.cs` writes recordings to
 `%USERPROFILE%\Downloads` or `SpecialFolder.MyVideos` (`DefaultRecordFolder()`, line
 173–179), with `Microsoft.Win32.OpenFolderDialog` for overrides (`ChooseRecordFolder()`,
 line 151). The whole temp-write-then-move lifecycle stays inside one directory
 (line 131–132).
 **This works only because we are full trust.** At `mediumIL` those writes pass through
 unvirtualized and `OpenFolderDialog` is an ordinary Win32 folder browser with no capability
 token involved. **No `broadFileSystemAccess` is needed.**
 ⚠️ **If anyone ever flips the manifest to `appContainer`, recording silently breaks** —
 `Directory.CreateDirectory` and `File.Move` start resolving to a per-package virtualized
 location. A code comment belongs at `DefaultRecordFolder()` **when the manifest lands**, not
 before (a comment describing a manifest that does not exist is worse than no comment).
 ---
 ## 6. Store policy verdicts — what binds, what doesn't
 Policy 7.20. "Binds" = must be satisfied to submit.
 ### ⛔ Binds — blockers or real work
 | Policy | Requirement | Our status |
 |---|---|---|
 | **10.2.2** | No dynamic code inclusion (download-and-execute) | ❌ **VIOLATED** — see §4. Fix: bundle ffmpeg |
 | **10.3.1** | Login required → supply a **working demo account** in certification notes | ☐ TODO — we require YouTube sign-in |
 | **10.5.1** | **Privacy policy mandatory**; URL in Partner Center. Desktop Bridge + Win32 **always** need one. Must state what PI is accessed/collected/transmitted, how used/stored/secured, types of parties disclosed to, controls the user has, compliance with law, and be kept current | ☐ TODO — `llamachile.shop` can host it |
 | **10.5.4** | Collect/store/transmit PI securely with modern cryptography | ✅ DPAPI for tokens, HTTPS to YouTube |
 | **10.5.5** | No highly sensitive PI (health/**financial**) unless tied to functionality + express consent | ⚠️ **SuperChat/reward path touches financial data** — keep display-text-only processing, never log payloads |
 | **10.6** | Declared capabilities must relate to the product's functions; **must not circumvent OS checks** | ✅ camera/mic for a broadcast tool is self-evident; must use standard MF/DShow/WASAPI paths |
 | **10.7** | Localize for every declared language; declare **English only** | ☐ Keep the manifest to one language |
 | **10.1.1** | Title must be unique, **no marketing or descriptive text, no extraneous keywords** | Store name is exactly `LlamaCasty` |
 | **10.1.3** | Search terms: max 7, no pricing terms, **no other product titles** unless you published them | ☐ Cannot list `OBS` or `StreamYard` as search terms |
 | **10.1.4** | Distinct informative metadata + **active Store presence** | ☐ Listing must not be a stub |
 | **10.2.7** | Must enable clean uninstall | ☐ MSIX gives this free |
 | **10.4.2** | Start promptly, stay responsive, shut down gracefully, survive native API exceptions | ✅ `AppLog` + dispatcher handlers exist |
 | **10.11.1** | **IARC age-rating questionnaire** required | ☐ General-audience streaming tool, 12+ territory |
 | **10.11.2** | Keep the rating accurate as features change | ☐ Re-visit if audience-facing features shift |
 | **11.12** | **User Generated Content** — see §9 | ⚠️ Judgment call, documented not built |
 | **10.8.1** | Non-game PC products **may** use a secure third-party purchase API **or** Store IAP | ✅ **Superseded 2026-09-27: we chose Store IAP, not Polar.** The third-party-purchase path is no longer the plan |
 | **10.8.2** | Third-party purchase: identify provider, authenticate user, obtain confirmation, PCI DSS, note in Partner Center | ⛔ **Void — Polar is being torn down (TASK 10).** Store IAP is the Microsoft commerce engine, so the third-party-provider/PCI-DSS obligations do not apply |
 | **10.8.3** | **Individual** accounts cannot require financial info for primary functionality; requiring it forces a **Company** account | ⚠️ **Open question** — see §11 |
 | **10.14** | Individual accounts usually fine for a solo dev; Company required if the product needs financial info for primary functionality, or a consumer would read the name as a business | ⚠️ Same question as 10.8.3 |
 | **10.8.7** | Pricing must follow the FTC Guides Against Deceptive Pricing and must not be irrationally high vs. features | ☐ A pricing decision, not a code task |
 | **10.5.8** | Must **follow** applicable safety/privacy laws re children | ☐ Follow-the-law obligation — see §8 |
 | **10.1.5** | May enable acquisition of your other Store products or add-ons | N/A |
 ### ✅ Does NOT bind — recorded so it is never re-raised
 | Policy | Why it doesn't apply |
 |---|---|
 | **10.10** (Advertising) | **Ads are injected server-side by YouTube after the RTMP handoff.** LlamaCasty displays no ads, renders no ad SDK, and controls no ad decision. Every 10.10 clause is conditioned on ads *your product displays*. Not applicable. |
 | **10.2.5** (Store-only install) | 7.20 applies "installed and updated only through the Store" to **game products and Xbox console products**. A non-game PC app is not locked to MSIX. *(The 2018 v7.7 wording said "all of your apps" — that language has been narrowed.)* |
 | **10.2.3** (secondary software) | ffmpeg **enhances** the product's functionality, and once bundled it is not "offered to install" as separate software |
 | **10.2.8** (Windows settings) | `RegisterHotKey` and standard DShow/MF paths are supported APIs. No accessibility-API or undocumented-API tricks |
 | **10.10.1 / 10.10.2** | Follows from 10.10 — no ads displayed |
 | **11.13** (Storefront) | Not a storefront |
 | **11.14** (Gambling) | Not applicable |
 | **11.15** (Child Safety) | Prohibits products enabling exploitation/grooming/sexualization/sextortion/trafficking, and adult-themed products targeting children. A broadcast tool is not in this class. Nothing LlamaCasty does creates, uploads, or distributes child-exploiting content |
 | **10.5.2** | We do not publish a customer's PI to an outside service beyond the stream they themselves broadcast |
 | **10.5.7** (location) | No device location access |
 | **10.2.9** | Only if we chose the Store EXE route. It would bind — see §3, route D is dominated |
 ### Certification mechanics
 - Technical compliance is tested by the **Windows App Certification Kit** before submission.
 - Certification takes **up to 3 business days**; the listing appears ~15 min after publish.
 - MSIX package requirements: SHA2-256 block map, `StoreManifest`, 25 GB max.
 - Partner Center account: individual vs company — see §11.
 ---
 ## 7. MSIX disqualifiers we do NOT trip
 Verified by grep across the codebase 2026-09-27. The MSIX prep docs list four hard
 disqualifiers; **all four are clear**:
 | Disqualifier | Our status |
 |---|---|
 | "Your application requires a Windows driver. MSIX doesn't support Windows drivers." | ✅ We **consume** DShow filters, we don't install a driver. (A creator's third-party Virtual Capture Device is their hardware, not something we ship.) |
 | "Your application requires a user Windows service. MSIX doesn't support per-user Windows services." | ✅ No service installation anywhere |
 | Apps requiring **elevation** for any functionality are not accepted | ✅ No `requireAdministrator` / `highestAvailable` / UAC manifest |
 | "Your app's modules are loaded in-process to processes that are not in your Windows app package" (shell extensions, etc.) | ✅ No shell extensions, no in-process module loading, no jump lists |
 Also verified: there is **no `.manifest` file in the repo at all** today, so packaging is
 purely additive — a new `Package.appxmanifest` plus a packaging project. The existing
 unpackaged exe keeps working.
 ### Other store rules worth knowing while listing
 - **10.1.4** requires an active Store presence — the listing cannot be a placeholder.
 - **10.7** — declare English only, or localize the description into every declared language.
 - **10.9** — the app must stay functional when notifications are disabled. Our toast stack
  must not be load-bearing.
 ---
 ## 8. Minors, COPPA, and the age question
 ### The operator is 13+ by construction
 YouTube Terms of Service:
 - **"You must be at least 13 years old to use the Service"**
 - 13–17 permitted **with parent/guardian permission**
 - **Under 13 cannot create an account** — exceptions are YouTube Kids and supervised
  accounts via Family Link or Google Workspace for Education
 - Google Accounts: 13 is the minimum to self-manage
 - **The floor varies by region** — at least one YouTube ToS variant states 14, tracking EU
  digital-consent ages. Treat it as 13–14, not a fixed 13.
 **Why this does real work:** LlamaCasty *requires* a YouTube account to operate, because
 streaming requires one. So the person running the broadcast is 13+ by construction. A
 COPPA theory premised on "a service collecting personal information from children under 13"
 has no purchase against the operator — and that is true **by construction, not by promise**.
 That is the cleanest sentence available for a certification note.
 ### The residual exposure
 The **viewers** may still be under 13 on supervised/family-linked accounts, so the chat
 ingestion point does not fully disappear. It weakens substantially, because:
 - Live chat is restricted/disabled on supervised YouTube kid accounts
 - YouTube moderates the messages before we ever see them (§9)
 - Our mitigation: **retain nothing** — parse, display, discard (see `task-49`)
 ### COPPA is very unlikely to bind
 COPPA applies to child-directed services and to operators collecting PI from children under
 13. The three-factor test (subject matter, audience, evidence of child focus) is nowhere
 near met by a broadcast tool aimed at a gaming audience. **10.5.8 is a follow-the-law
 obligation, not a be-child-safe obligation** — it says "follow all applicable laws," it does
 not impose COPPA duties on us directly.
 **But note the enforcement trend** (FTC, September 2025 Apitor settlement): operators are
 held responsible for **what third-party components collect on their behalf**, and the FTC
 expects a real inquiry into third-party collection practices. That case was about an SDK;
 the principle is what matters for a chat pipe. This is a documentation obligation, and the
 answer is "we integrate no third-party analytics or ad SDKs, and we persist no chat or
 reward payloads."
 ---
 ## 9. 11.12 User Generated Content — the judgment call
 11.12 triggers on "content that users contribute to a product and which can be viewed or
 accessed by other users **in an online state**." **Chat is literally that.** If a reviewer
 classifies the chat surface as UGC, the requirements are:
 1. Published **terms of service, code of conduct, and/or content guidelines** for UGC,
   accessible **in-product and on your website**
 2. A **means for users to report** inappropriate/illegal/harmful UGC to the developer for
   review, and/or proactive detection
 3. Respect **user safety, parental, and content privilege settings**, and handle restricted
   access gracefully
 4. **Remove or disable UGC when requested by Microsoft**
 5. Disclose that content is **not created by the developer/publisher** where appropriate
 ### The argument: YouTube discharges the moderation obligation upstream
 | 11.12 asks for | How YouTube already covers it |
 |---|---|
 | Published ToS / CoC / content guidelines | Community Guidelines, linkable from our listing |
 | A reporting mechanism | Creator-side chat reporting; YouTube enforces |
 | Respect parental / privilege settings | YouTube's restricted + supervised accounts |
 | Remove/disable on request | YouTube removes; we never hosted the original |
 | Disclose third-party UGC origin | Visibly YouTube chat; YouTube is platform of record |
 **And the enforcement is demonstrably real.** YouTube's transparency report for
 **Jan–Mar 2026**: approximately **1.6 billion comments removed in a single quarter**, with
 **child safety the #2 removal reason at 124,624,293** (hateful/abusive 15,977,127;
 harassment/cyberbullying 71,326,861; spam/scams 1.31 B).
 **The certification-note sentence:**
 > UGC is mirrored from YouTube, which moderates it at industrial scale upstream. We render
 > transiently, persist nothing, and provide no user-to-user communication surface.
 **The "persist nothing" half is ours to keep** — and it is the same property
 `task-49` (profanity filter) needs. Convenient, not coincidental.
 **Our read:** 11.12 targets products hosting a UGC *community*. A chat *mirror* rendered
 from YouTube — where YouTube is the platform of record and already supplies reporting,
 age-gating, and parental controls — is arguably not "our" UGC. **This is a judgment call,
 and we resolve it by documenting the position rather than building features on a guess.**
 State the reasoning in the certification notes; Microsoft reads them.
 ### The documentation we owe regardless
 | Artifact | Requirement |
 |---|---|
 | **Privacy policy** on `llamachile.shop` | 10.5.1. Must state: camera/mic access is user-directed and OS-gated; **no retention** of chat or reward payloads; no viewer data collected; **ffmpeg is bundled, nothing is fetched at runtime** |
 | **Code of conduct + content guidelines** | 11.12 / 11.15. General audience; explicitly not directed at under-13s |
 | **IARC age-rating questionnaire** | 10.11.1 |
 | **Certification notes** | the 11.12 reading, the YouTube age-gate argument, the Polar third-party purchase box, the demo account |
 ---
 ## 10. Camera, microphone, and "only when the user says so"
 **We do not write that certification. Windows does it — and the Store forbids us from
 bypassing it.** Three layers:
 1. **Policy 10.6** — "You must not circumvent operating system checks for capability
   usage." Route through the standard OS consent path; do not roll our own.
 2. **Windows privacy settings** — Settings → Privacy & security → Camera / Microphone.
   Since **Windows 10 1903**, *"Let desktop apps access your camera/microphone"* is the
   toggle that governs a Win32 broadcast app. Turn it off and the app loses access. **That
   is the "explicit user direction" mechanism, enforced by the OS, not by our EULA.**
 3. **Hardware/OS indicators** — camera light (or a notification when there is no light) and
   a microphone icon in the taskbar tray. Automatic. The OS is the disclosure mechanism, so
   we get neither credit nor blame from it.
 ### ⚠️ The open question — measure, don't assume
 Microsoft's own support page carries this caveat:
 > Desktop apps may not always appear in the list of apps available to the Camera and
 > Microphone settings pages or might still be able to access your camera or microphone even
 > when these settings are turned off.
 **Untested: does the Win11 desktop-app camera toggle reliably gate a DShow webcam and a
 capture card?**
 - If it **does** gate them, we can make privacy-forward claims after verifying.
 - If it **does not**, that is **not** a Store certification failure — we declared `webcam`
  honestly and use supported APIs — but it is a real user-trust issue, and we must not
  write privacy-forward marketing copy on the assumption that it works.
 **Tracked as an open item in `TASKS.md`. A guard note in `MARCOM.md` blocks privacy-forward
 copy until it passes.**
 ---
 ## 11. Open questions
 1. **Individual or Company Partner Center account?** (10.8.3 / 10.14.) Individual accounts
   are "usually appropriate for a single developer working on their own," and a Company
   account is required if the product requires financial account information **for primary
   functionality**. Polar collects payment externally and we never ask the user for card
   details, so we look like a clean individual case — but it is a question for Partner
   Center, and getting it wrong means re-enrolling.
 2. **Does the desktop-app camera toggle gate DShow?** (§10) — gates the `MARCOM.md`
   privacy claim.
 3. **MSIX write behavior under a real package identity** — full trust passes writes through
   per the docs, but worth confirming on a real packaged build before trusting it with
   recordings.
 4. **Store revenue-share terms** — do not plan on any specific percentage. The terms have
   moved more than once and small indie apps sometimes qualify for better rates. Verify
   current terms and conditions before pricing against them.
 5. **`liveBroadcasts.insert` requires `status.selfDeclaredMadeForKids`** (COPPA) — already
   known, see [`research-youtube-api.md`](research-youtube-api.md) item 1. Confirm the
   dialog wording is right for a tool that is never child-directed.
 ---
 ## 12. Profanity filter — design constraints (feeds `task-49`)
 YouTube's Community Guidelines carry a specific **Vulgar language policy** under
 "Sensitive content," alongside nudity/sexual content, child safety, and self-harm. So
 profanity is a named policy surface, not an edge case.
 Three external reasons it earns a slot, plus the real one:
 1. YouTube treats it as policy-relevant, so 11.12's "proactive detection" language has
   something to attach to
 2. Competitive parity — overlay tools in this lane generally offer it
 3. It is a reasonable reading of 11.12's proactive-detection language
 4. **The real reason: we control what gets projected on screen.** That is the creator's
   call, not YouTube's.
 **Four constraints, because they protect the privacy story rather than complicate it:**
 1. **Local and on-device only.** No server, no telemetry of message content, nothing leaves
   the machine.
 2. **Non-persistent.** Filter at ingest, discard the raw text, keep only the display
   string. Same property that makes the 11.12 answer in §9 strong.
 3. **User-supplied word list**, opt-in, stored locally. **Not a hardcoded slur list baked
   into the binary** — that is an unpleasant artifact, generates false positives across
   dialects and languages, and becomes our problem the moment someone extracts it. A
   user-curated list is also simply more useful: streamers know their community's
   euphemisms and we do not.
 4. **Match display text only.** Never the SuperChat amount or any reward-event field —
   those are financial data under 10.5.5, and matching on them would be a real mistake.
 The existing alert box already has a ticker and three display methods
 (`Controls/OverlayHost.xaml`, `ViewModels/MainViewModel.Chat.cs`), so there is probably a
 **single insertion point** rather than scattered call sites. Verify before building.
@@ -0,0 +1,33 @@
 # ytLlive — YouTube Live API research facts (authoritative)
 > Catalog: [`TASKS.md`](../TASKS.md) · memory map: [`schema.md`](../schema.md).
 ## YouTube Live API — research facts (authoritative, v3 build)
 Lifecycle: `created → ready → [testing] → live → complete` (transitional `liveStarting` / `testStarting`).
 1. **liveBroadcasts.insert** requires: `snippet.title`, `snippet.scheduledStartTime`, `status.privacyStatus`, `status.selfDeclaredMadeForKids` (COPPA).
 2. **liveStreams.insert** requires: `snippet.title`, `cdn.frameRate`, `cdn.ingestionType`, `cdn.resolution`. **None of the four (except title) can ever change after creation** — changing them means delete + recreate the stream. This is the hard constraint behind the quality grey-out.
 3. **Title / description / privacy**: editable at any time, including while live (`liveBroadcasts.update`, part=`snippet,status`).
 4. **contentDetails** (DVR, recordFromStart, monitorStream, embed, latency): editable only in `created` / `ready`.
 5. **Transition to live** only allowed when the bound stream's `status.streamStatus == active`.
 ### Two features that reshape the design
 1. **enableAutoStart / enableAutoStop** — instant one-click go-live, no transition call. With `enableAutoStart=true` we never call `transition(live)`: the broadcast auto-goes-live the moment the encoder starts. Combined with `enableMonitorStream=false` (our preview pane replaces YouTube's monitor stream — the thing that forces a testing stage), the flow is **create → bind → Start Stream → encoder starts → YouTube brings it live**. No testing, no transition polling, no liveStarting stuck-state handling.
 2. **`cdn.resolution=variable` / `cdn.frameRate=variable`** — free auto step-down. YouTube auto-detects what we send; since we ARE the encoder we can drop bitrate/resolution on the fly with zero API calls. Declaring an explicit resolution instead (e.g. 1080p) requires a new stream, which can't happen mid-broadcast. Variable is the enabler for the whole auto step-down feature. **(Claim-check 2026-09-01: the enabler is real, the governor is not built — the drop-side policy ships as TASK 33, v1 per the complete-v1 ruling.)**
 ### Compliance gotchas (maps perfectly to report-by-exception)
 1. `liveStreams.status.healthStatus`: `good | ok | bad | noData` plus `configurationIssues[]` with `type` + `severity` (`info|warning|error`). Literally built for report-by-exception — poll it, render nothing on good/ok, surface a banner only on warning/error. No need to invent our own health logic.
 2. Encoder must comply or YouTube flags it: keyframes ≤ 4s (`gopSizeLong`), closed GOP, H.264, audio AAC/MP3 @ 44.1/48kHz, mono/stereo only.
 3. Error codes to handle: `errorStreamInactive`, `invalidTransition`, `redundantTransition`, `liveStreamDeletionNotAllowed`, `liveStreamModificationNotAllowed`, `liveBroadcastBindingNotAllowed`.
 ### Tips we should take advantage of
 1. **Reusable streams** (`isReusable=true`): one stream per channel, cache its ingestion URL + stream name, reuse for every broadcast. No rebinding dance each go-live. This is exactly the manual-stream-key baseline.
 2. **Backup ingestion address**: YouTube provides a simultaneous-push backup — future hardening, not v1.
 3. **`recordFromStart` + `enableDvr` default true** → every live is auto-recorded and immediately replayable. Free VOD archive, matches the v0.2 recording goal.
 4. **`latencyPreference`: `normal | low | ultraLow`** — for homelab streamers talking to chat, `low` (or `ultraLow`, capped at 1080p) is a real feature.
 5. **Broadcast ID == Video ID** — one ID to track everything.
@@ -0,0 +1,15 @@
 # TASK 1 — Initial Scaffold
 > Catalog: [`TASKS.md`](../TASKS.md) — status and requirements live here.
 **Goal:** Working C# / WPF project with MVVM architecture, dark-theme main window, and YouTube service stubs.
 ### Status: ✅ Done
 1. ✅ Models: Scene, Source, StreamConfig, StreamHealth, YouTubeChannel, ChatMessage
 2. ✅ Services: YouTubeAuthService (OAuth2), YouTubeStreamService (broadcast/health), YouTubeChatService (chat polling)
 3. ✅ MainViewModel: scene management, stream controls, chat
 4. ✅ MainWindow: scene/source panel, preview area, chat panel, status bar
 5. ✅ Clean build, 0 warnings (WSL + Windows)
@@ -0,0 +1,37 @@
 # TASK 2 — YouTube OAuth2 Authentication
 > Catalog: [`TASKS.md`](../TASKS.md) — status and requirements live here.
 **Goal:** Fully working Google OAuth2 flow — user clicks "YouTube", browser opens, authorization callback lands, channel info is stored.
 ### Status: ✅ Done
 1. ✅ Two-state Start/End Stream button, go-live dialog (account + title/description/visibility), red top bar, pulsing LIVE badge + elapsed timer, preview glow, taskbar red dot
 2. ✅ Real OAuth2 wiring — baked-in Google credentials (desktop client; loopback callback) + `YouTubeAuthService` complete: browser launch, `HttpListener` callback, token exchange, refresh, channel fetch
 3. ✅ Token persistence via Windows DPAPI (`Helpers/TokenStore.cs` → `%APPDATA%\ytLlive\ytLlive.auth`), best-effort reload + proactive refresh at startup, saved after every exchange/refresh
 4. ✅ Account sign-in/change surfaced in the GoLive dialog (saved account shown with "Change Account"; "Sign in to YouTube" when none; Start disabled until signed in)
 5. ✅ ~~**End Livestream signs out**~~ **SUPERSEDED by TASK 18 (2026-08-29): explicit sign-out only** — `StopStream()` no longer clears the session (sign out via Logout / Change Account, `SignOutYouTubeAsync`); stopping a stream or recording leaves the creator signed in. Originally shipped as: a graceful end completes the session: `StopStream()` calls `YouTubeAuthService.ClearSession()` + `TokenStore.Clear()` + `IsConnected = false`, so the next Start Stream dialog requires a fresh sign-in. A crash never runs End, so the DPAPI token survives and the creator stays signed in. Resume/reconnect after a midstream crash is deliberately deferred to TASK 3: the socket can't be resumed (it dies with the process), so "resume" = fast reconnect with a saved broadcast ID/stream key within YouTube's disconnect-grace window; too slow and `enableAutoStop` ends the broadcast. **Orphan closed 2026-09-01:** this mechanism is owned by **TASK 32 (Stream resilience)** — in-session blip retry inside the grace window; cross-process "resume" of a dead broadcast is officially out-of-product (the API makes it impossible — creator ruling).
 6. ✅ Tests in `ytLive.Tests` (xUnit, net8.0-windows): TokenStore DPAPI roundtrip/corrupt/missing/clear + mocked exchange channel-parse + refresh expiry bump + `ClearSession` — 7 passing
 **Design constraint:** Sign-in must NEVER block core exploration. Users can build scenes, add sources, and audition the software without authenticating. But **going live requires authentication** — the "Start Stream" dialog is where the account sign-in lives, alongside all stream metadata.
 **Two-state flow:** There is no separate "Connect" button. The top bar shows a single button — **Start Stream** when idle, **End Stream** when live. Clicking Start Stream opens one dialog that supplies everything: account (previously-saved account shown as default, with a Change Account action) + title/description/visibility.
 **Live indicators (unmissable):** Top bar + window title bar flip red, a pulsing **● LIVE** badge with elapsed timer appears in the top bar, the preview area gets a red glow, and the taskbar icon shows a red overlay dot. Window title bar shows the stream title once validated.
 ### Requirements:
 1. **Google Cloud OAuth credentials** — client ID + secret, **baked into `Helpers/OAuthCredentials.cs`** (desktop "Desktop app" OAuth client; loopback callback — no console redirect URI registration needed; creators never configure)
 2. **Local HTTP listener** — `HttpListener` on `http://localhost:PORT/oauth2/callback` to catch the redirect
 3. **Browser launch** — open the authorization URL in the default browser
 4. **Token persistence** — store access/refresh tokens securely (Windows DPAPI), reload on startup
 5. **UI state** — account shown in the Start Stream dialog; "Change Account" action triggers re-auth
 6. **Go Live gated on auth** — Start Stream dialog requires sign-in to enable the Start button; scene building works without it
 ### Tests:
 1. Mock token exchange response, verify channel info parsed
 2. Verify token refresh triggers when near expiry
 3. Verify credential load/save roundtrip
--- a/Show More
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