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 Point _grabOffset;
    private double _resizeAspect;

    private readonly System.Collections.Generic.Dictionary<string, Storyboard> _activeBorderAnimations =
        new();

    private DispatcherTimer? _socialGlowTimer;
    private double _socialGlowAngle;

    public PreviewPane()
    {
        InitializeComponent();
    }

    // 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 || !vm.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 = 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)
        => 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(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;
    }
}