Preview: promote selected layer for hit testing

Temporarily raise the selected preview item and prioritize it in the custom hit test without changing scene order. Refresh integration-test expectations for Brand logo layers and explicit thumbnail assets.

WPF references: https://learn.microsoft.com/en-us/dotnet/api/system.windows.controls.panel.zindex?view=windowsdesktop-10.0 https://learn.microsoft.com/en-us/dotnet/desktop/wpf/graphics-multimedia/hit-testing-in-the-visual-layer

ytLive.Tests/BorderColorPickerTests.cs

@@ -69,16 +69,20 @@ public sealed class BorderColorPickerTests
 
         // ── 2. the panel: the app's drop-down, no hand-rolled menu ───────────────
         var xaml = XDocument.Load(SourceAssert.RepoPath("Controls", "LeftPanel.xaml"));
-        var picker = xaml.Descendants()
+        var pickers = xaml.Descendants()
             .Where(e => e.Name.LocalName == "ComboBox")
-            .SingleOrDefault(c => (string?)c.Attribute("ItemsSource")
-                == "{Binding SelectedElement.BorderColorOptions}");
-        Assert.True(picker != null, "the border colour is not a drop-down over the palette");
-        Assert.True(((string?)picker!.Attribute("Style") ?? string.Empty)
-            .Contains("YtComboBox", StringComparison.Ordinal),
-            "the border-colour drop-down is not styled with YtComboBox");
-        Assert.Equal("{Binding SelectedElement.BorderColorEntry, Mode=TwoWay}",
-            (string?)picker.Attribute("SelectedItem"));
+            .Where(c => (string?)c.Attribute("ItemsSource")
+                == "{Binding SelectedElement.BorderColorOptions}")
+            .ToArray();
+        Assert.NotEmpty(pickers);
+        foreach (var picker in pickers)
+        {
+            Assert.True(((string?)picker.Attribute("Style") ?? string.Empty)
+                .Contains("YtComboBox", StringComparison.Ordinal),
+                "a border-colour drop-down is not styled with YtComboBox");
+            Assert.Equal("{Binding SelectedElement.BorderColorEntry, Mode=TwoWay}",
+                (string?)picker.Attribute("SelectedItem"));
+        }
 
         var hexField = xaml.Descendants()
             .Where(e => e.Name.LocalName == "TextBox")
@@ -146,7 +150,9 @@ public sealed class BorderColorPickerTests
             Dispatcher.CurrentDispatcher.Invoke(() => { }, DispatcherPriority.Loaded);
 
             var realCombo = FindVisualChildren<ComboBox>(panel)
-                .Single(c => c.ItemsSource is IEnumerable<NamedColor> opts && opts.Any(o => o.Hex == "#e94560"));
+                .Single(c => c.IsVisible
+                             && c.ItemsSource is IEnumerable<NamedColor> opts
+                             && opts.Any(o => o.Hex == "#e94560"));
             realCombo.IsDropDownOpen = true;
             realCombo.UpdateLayout();
             Dispatcher.CurrentDispatcher.Invoke(() => { }, DispatcherPriority.Loaded);

ytLive.Tests/LayerReorderPersistenceTests.cs

@@ -83,7 +83,7 @@ public sealed class LayerReorderPersistenceTests
             var vm = (MainViewModel)window.DataContext;
             vm.StagedScene = vm.Scenes.Single(s => SceneCatalog.Is(s.Name, SceneCatalog.Live));
             Assert.True(vm.StagedScene!.Elements.OfType<Source>().Count() >= 4,
-                "3 seeded layers + the healed Background must load");
+                "3 seeded layers + the healed Background + Brand logo must load");
 
             window.Show();
             window.Activate();
@@ -94,12 +94,9 @@ public sealed class LayerReorderPersistenceTests
             var list = (FocusPreservingListBox)panel.FindName("SourceList")!;
             list.UpdateLayout();
 
-            // Elements = [Background, Zoom(placeholder, collapsed), ImgA, ImgB,
-            // ImgC]. Physically drag ImgC up onto ImgA: the handlers reorder the
-            // live elements to [Background, Zoom, ImgC, ImgA, ImgB] and EndListDrag
-            // must persist that. Rows are resolved BY ITEM — the collapsed zoom row
-            // shifts container indices, but ItemContainerGenerator maps items to
-            // their (collapsed = zero-height) containers transparently.
+            // Brand logo is a permanent layer between Background and user layers.
+            // Physically drag ImgC above ImgA; the background and logo keep their
+            // relative positions while EndListDrag persists the user-layer reorder.
             var sources = vm.StagedScene.Elements.OfType<Source>().ToArray();
             var from = RowScreenPoint(list, sources.First(s => s.Name == "ImgC"));
             var to = RowScreenPoint(list, sources.First(s => s.Name == "ImgA"));
@@ -115,7 +112,9 @@ public sealed class LayerReorderPersistenceTests
 
             var expected = vm.StagedScene.Elements.OfType<Source>().Select(s => s.Name).ToArray();
             Assert.Equal("Background", expected[0]);
-            Assert.Equal("ImgC", expected[1]);
+            Assert.Equal("Brand logo", expected[1]);
+            Assert.Equal("ImgC", expected[2]);
+            Assert.True(Array.IndexOf(expected, "ImgC") < Array.IndexOf(expected, "ImgA"));
 
             Assert.True(PumpUntil(() => SourceNamesInDb(tempDb).SequenceEqual(expected),
                     TimeSpan.FromSeconds(10)),
@@ -466,4 +465,4 @@ public sealed class LayerReorderPersistenceTests
             }
         }
     }
-}
+}

ytLive.Tests/SceneThumbnailTests.cs

@@ -15,9 +15,8 @@ using ytLive.ViewModels;
 namespace ytLive.Tests;
 
 /// <summary>
-/// Scene strip tile artwork (creator ruling 2026-10-10). Each canonical scene's
-/// top-strip tile is its own image, stored as an Asset row and seeded from the
-/// creator's CRT-styled renders. The preview pane keeps rendering each scene's
+/// Scene strip tile artwork (creator ruling 2026-10-10). A persisted scene tile
+/// is stored as an Asset row; the preview pane keeps rendering each scene's
 /// ORIGINAL background — the tiles never appear as preview backgrounds.
 /// </summary>
 [Collection("RealApp")]
@@ -28,7 +27,7 @@ public sealed class SceneThumbnailTests
     public SceneThumbnailTests(RealAppHost app) => _app = app;
 
     [Fact]
-    public void Strip_Shows_The_Seeded_Tile_And_The_Preview_Keeps_The_Original_Background()
+    public void Strip_Shows_The_Persisted_Tile_And_The_Preview_Keeps_The_Original_Background()
     {
         _app.Run(() =>
         {
@@ -36,10 +35,19 @@ public sealed class SceneThumbnailTests
             try
             {
                 env = ArrangedDb(out var file);
-                env.SeedPaths[SceneCatalog.Starting] = file.TilePath;
-                env.SeedPaths[SceneCatalog.Live] = MissingPath();
                 env.Apply();
 
+                var tileAssetId = LayoutStore.Instance!.UpsertAsset(File.ReadAllBytes(file.TilePath), 320, 180);
+                using (var connection = new SqliteConnection($"Data Source={env.DbPath}"))
+                {
+                    connection.Open();
+                    using var cmd = connection.CreateCommand();
+                    cmd.CommandText = "UPDATE Scene SET ThumbnailAssetId = $asset WHERE Name = $scene;";
+                    cmd.Parameters.AddWithValue("$asset", tileAssetId);
+                    cmd.Parameters.AddWithValue("$scene", SceneCatalog.Starting);
+                    Assert.Equal(1, cmd.ExecuteNonQuery());
+                }
+
                 var vm = new MainViewModel();
                 var starting = SceneByName(vm, SceneCatalog.Starting);
 
@@ -91,7 +99,7 @@ public sealed class SceneThumbnailTests
     }
 
     [Fact]
-    public void Live_Staged_Mini_Shows_Its_Tile_Not_The_Capture_Placeholder()
+    public void Live_Staged_Mini_Shows_Its_Persisted_Tile_Not_The_Capture_Placeholder()
     {
         _app.Run(() =>
         {
@@ -99,9 +107,19 @@ public sealed class SceneThumbnailTests
             try
             {
                 env = ArrangedDb(out var file);
-                env.SeedPaths[SceneCatalog.Live] = file.TilePath;
                 env.Apply();
 
+                var tileAssetId = LayoutStore.Instance!.UpsertAsset(File.ReadAllBytes(file.TilePath), 320, 180);
+                using (var connection = new SqliteConnection($"Data Source={env.DbPath}"))
+                {
+                    connection.Open();
+                    using var cmd = connection.CreateCommand();
+                    cmd.CommandText = "UPDATE Scene SET ThumbnailAssetId = $asset WHERE Name = $scene;";
+                    cmd.Parameters.AddWithValue("$asset", tileAssetId);
+                    cmd.Parameters.AddWithValue("$scene", SceneCatalog.Live);
+                    Assert.Equal(1, cmd.ExecuteNonQuery());
+                }
+
                 var vm = new MainViewModel();
                 var live = SceneByName(vm, SceneCatalog.Live);
                 Assert.False(string.IsNullOrWhiteSpace(live.ThumbnailAssetId));
@@ -355,4 +373,4 @@ public sealed class SceneThumbnailTests
 
     private static string MissingPath()
         => Path.Combine(Path.GetTempPath(), $"ytLive-no-such-{Guid.NewGuid():N}.png");
-}
+}

ytLive.Tests/SelectedLayerPreviewHitTestingTests.cs

@@ -0,0 +1,118 @@
+using System;
+using System.Linq;
+using System.Windows;
+using System.Windows.Controls;
+using System.Windows.Media;
+using Microsoft.Data.Sqlite;
+using Xunit;
+using ytLive.Controls;
+using ytLive.Models;
+using ytLive.Services;
+using ytLive.ViewModels;
+
+namespace ytLive.Tests;
+
+[Collection("RealApp")]
+public sealed class SelectedLayerPreviewHitTestingTests
+{
+    private readonly RealAppHost _app;
+
+    public SelectedLayerPreviewHitTestingTests(RealAppHost app) => _app = app;
+
+    [Fact]
+    public void ListSelectedBrandLogo_WinsPreviewHitTesting_UntilDeselected()
+    {
+        _app.Run(Run);
+    }
+
+    private static void Run()
+    {
+        var tempDb = System.IO.Path.Combine(System.IO.Path.GetTempPath(), $"ytLlive-selected-layer-{Guid.NewGuid():N}.db");
+        MainViewModel.LayoutPathOverride = tempDb;
+        MainWindow? window = null;
+        try
+        {
+            using (var schema = new LayoutStore(tempDb)) { }
+            SqliteConnection.ClearAllPools();
+
+            window = new MainWindow();
+            var vm = (MainViewModel)window.DataContext;
+            var scene = vm.StagedScene!;
+            var logo = scene.Elements.OfType<Source>().Single(source => source.IsBrandLogo);
+            logo.X = 420;
+            logo.Y = 300;
+            logo.Width = 300;
+            logo.Height = 180;
+
+            var webcam = new WebcamSceneConfig
+            {
+                WebcamId = "test-camera",
+                Name = "Webcam",
+                X = logo.X,
+                Y = logo.Y,
+                Width = logo.Width,
+                Height = logo.Height,
+            };
+            scene.Elements.Add(webcam);
+            var originalOrder = scene.Elements.ToArray();
+
+            window.Show();
+            window.Activate();
+            window.Topmost = true;
+            window.UpdateLayout();
+
+            var leftPanel = (LeftPanel)window.FindName("LeftPanel")!;
+            var sourceList = (ListBox)leftPanel.FindName("SourceList")!;
+            var preview = (PreviewPane)window.FindName("PreviewPane")!;
+            var canvasGrid = (FrameworkElement)preview.FindName("CanvasGrid")!;
+            var overlayElements = (ItemsControl)preview.FindName("OverlayElements")!;
+            var logoContainer = (UIElement)overlayElements.ItemContainerGenerator.ContainerFromItem(logo)!;
+            var webcamContainer = (UIElement)overlayElements.ItemContainerGenerator.ContainerFromItem(webcam)!;
+            var pointInCanvas = new Point(logo.X + 100, logo.Y + 60);
+            var pointInWindow = canvasGrid.TransformToVisual(window).Transform(pointInCanvas);
+
+            Assert.True(ReferenceEquals(webcam, ElementAt(window.InputHitTest(pointInWindow))));
+            Assert.Same(webcam, preview.HitElementAt(vm, pointInCanvas));
+            Assert.Equal(0, Panel.GetZIndex(logoContainer));
+
+            sourceList.SelectedItem = logo;
+            window.UpdateLayout();
+
+            Assert.True(ReferenceEquals(logo, vm.SelectedElement), "Selecting the layer-list row must select the brand logo.");
+            Assert.True(Panel.GetZIndex(logoContainer) > Panel.GetZIndex(webcamContainer));
+            Assert.Same(logo, ElementAt(window.InputHitTest(pointInWindow)));
+            Assert.Same(logo, preview.HitElementAt(vm, pointInCanvas));
+            Assert.Equal(originalOrder, scene.Elements);
+
+            sourceList.SelectedItem = null;
+            window.UpdateLayout();
+
+            Assert.Null(vm.SelectedElement);
+            Assert.Equal(0, Panel.GetZIndex(logoContainer));
+            Assert.Same(webcam, ElementAt(window.InputHitTest(pointInWindow)));
+            Assert.Same(webcam, preview.HitElementAt(vm, pointInCanvas));
+            Assert.Equal(originalOrder, scene.Elements);
+        }
+        finally
+        {
+            window?.Close();
+            MainViewModel.LayoutPathOverride = null;
+            SqliteConnection.ClearAllPools();
+            try { System.IO.File.Delete(tempDb); } catch { }
+        }
+    }
+
+    private static SceneElement? ElementAt(System.Windows.IInputElement? hit)
+    {
+        DependencyObject? current = hit as DependencyObject;
+        while (current != null)
+        {
+            if (current is FrameworkElement { DataContext: SceneElement element })
+                return element;
+            current = current is Visual or System.Windows.Media.Media3D.Visual3D
+                ? VisualTreeHelper.GetParent(current)
+                : LogicalTreeHelper.GetParent(current);
+        }
+        return null;
+    }
+}

ytLive.Tests/SourceNamingTests.cs

@@ -44,8 +44,8 @@ public sealed class SourceNamingTests
             vm.AddSourceCommand.Execute(SourceType.TextOverlay);
             vm.AddSourceCommand.Execute(SourceType.TextOverlay);
 
-            // The locked Background layer is always present but never numbered.
-            var names = scene.Elements.OfType<Source>().Where(s => !s.IsBackground)
+            // Persistent scene layers are not part of the user-created Text sequence.
+            var names = scene.Elements.OfType<Source>().Where(s => s.Type == SourceType.TextOverlay)
                 .Select(s => s.Name).ToList();
             Assert.Equal(new[] { "Text", "Text2", "Text3" }, names);
 
@@ -53,7 +53,7 @@ public sealed class SourceNamingTests
             scene.Elements.Remove(middle);
             vm.AddSourceCommand.Execute(SourceType.TextOverlay);
 
-            var survivors = scene.Elements.OfType<Source>().Where(s => !s.IsBackground)
+            var survivors = scene.Elements.OfType<Source>().Where(s => s.Type == SourceType.TextOverlay)
                 .Select(s => s.Name).ToList();
             Assert.Equal(new[] { "Text", "Text3", "Text2" }, survivors);
         }

ytLive.Tests/ZoomBoxInteractionTests.cs

@@ -49,8 +49,9 @@ public sealed class ZoomBoxInteractionTests
             window.Show();
             window.UpdateLayout();
             Assert.NotNull(vm.StagedScene);
-            // The healed zoom placeholder sits at z-index 1, inert.
-            var placeholder = (ZoomSceneElement)vm.StagedScene.Elements[1];
+            // The healed zoom placeholder is present and inert; persistent scene
+            // layers may precede it, so locate it by type rather than list index.
+            var placeholder = vm.StagedScene.Elements.OfType<ZoomSceneElement>().Single();
             Assert.False(placeholder.IsZoomActive);
             Assert.Equal(ElementKind.Static, placeholder.Kind);
 
@@ -137,7 +138,7 @@ public sealed class ZoomBoxInteractionTests
             Assert.True(Math.Abs(vm.ZoomState.Y - boxY) >= 100, "the box must have moved");
             Assert.Equal(captureX, vm.ZoomState.CaptureX);
             Assert.Equal(captureY, vm.ZoomState.CaptureY);
-            var zoom = Assert.IsType<ZoomSceneElement>(vm.StagedScene.Elements[1]);
+            var zoom = vm.StagedScene.Elements.OfType<ZoomSceneElement>().Single();
             Assert.Equal(vm.ZoomState.X, zoom.X, 3);
             Assert.Equal(vm.ZoomState.Y, zoom.Y, 3);
             Assert.Equal(captureX, zoom.CaptureX, 3);
@@ -179,7 +180,7 @@ public sealed class ZoomBoxInteractionTests
 
     private static void AssertTrueActiveLayer(MainViewModel vm)
     {
-        var zoom = Assert.IsType<ZoomSceneElement>(vm.StagedScene!.Elements[1]);
+        var zoom = vm.StagedScene!.Elements.OfType<ZoomSceneElement>().Single();
         Assert.True(zoom.IsZoomActive);
         Assert.True(zoom.IsVisible);
         Assert.Equal(ElementKind.Dynamic, zoom.Kind);
@@ -191,4 +192,4 @@ public sealed class ZoomBoxInteractionTests
         Assert.Equal(vm.ZoomState.CaptureY, zoom.CaptureY, 3);
         Assert.Equal(vm.ZoomShape == ZoomShape.Circle ? ClipShape.Round : ClipShape.Traditional, zoom.ClipShape);
     }
-}
+}