using System;
using System.Linq;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Shapes;
using Microsoft.Data.Sqlite;
using Xunit;
using ytLive.Models;
using ytLive.ViewModels;

namespace ytLive.Tests;

/// <summary>
/// Verifies the zoom box created by a right-click in the live preview: every
/// ZoomView shape procures the right bounding box CENTERED on the click (circle
/// square, phone 9:16, tablet 16:9), the box stays fully inside the 1920x1080
/// preview, and — because the box is now a real composited layer (TASK 51) —
/// a ZoomSceneElement placeholder sits at z-index 1 whose rect mirrors the box,
/// its Kind flips Dynamic only while active, and the output crop stays the tier
/// (the box is never the crop source).
/// </summary>
[Collection("RealApp")]
public sealed class ZoomBoxInteractionTests
{
    private readonly RealAppHost _app;

    public ZoomBoxInteractionTests(RealAppHost app)
    {
        _app = app;
    }

    [Fact]
    public void Zoom_Shape_Controls_Box_Aspect_Anchor_Layer_And_Render()
    {
        _app.Run(Run);
    }

    private void Run()
    {
        var tempDb = System.IO.Path.Combine(System.IO.Path.GetTempPath(), $"ytLlive-test-{Guid.NewGuid():N}.db");
        MainViewModel.LayoutPathOverride = tempDb;
        var window = new MainWindow();
        var vm = (MainViewModel)window.DataContext;
        try
        {
            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];
            Assert.False(placeholder.IsZoomActive);
            Assert.Equal(ElementKind.Static, placeholder.Kind);

            vm.IsRecording = true;
            var pane = (UserControl)window.FindName("PreviewPane")!;
            var zoomBox = (Grid)pane.FindName("ZoomBox")!;
            var rectOutline = (Rectangle)pane.FindName("ZoomRectOutline")!;
            var circleOutline = (Ellipse)pane.FindName("ZoomCircleOutline")!;

            // Circle: square box, click point is the CENTER.
            vm.ZoomShape = ZoomShape.Circle;
            vm.ActivateZoom(1000, 500);
            Assert.True(vm.IsZoomActive);
            Assert.Equal(vm.ZoomState.Width, vm.ZoomState.Height, 3);
            Assert.Equal(1000 - vm.ZoomState.Width / 2, vm.ZoomState.X, 3);
            Assert.Equal(500 - vm.ZoomState.Height / 2, vm.ZoomState.Y, 3);
            AssertTrueActiveLayer(vm);

            window.UpdateLayout();
            Assert.Equal(Visibility.Visible, zoomBox.Visibility);
            Assert.IsType<EllipseGeometry>(zoomBox.Clip);
            Assert.Equal(Visibility.Visible, circleOutline.Visibility);
            Assert.Equal(Visibility.Collapsed, rectOutline.Visibility);

            // Phone (vertical rectangle): tall 9:16 box, click point is the CENTER.
            vm.ZoomShape = ZoomShape.VerticalRectangle;
            vm.ActivateZoom(960, 540);
            Assert.True(vm.ZoomState.Height > vm.ZoomState.Width);
            Assert.Equal(9.0 / 16.0, vm.ZoomState.Width / vm.ZoomState.Height, 3);
            Assert.Equal(960 - vm.ZoomState.Width / 2, vm.ZoomState.X, 3);
            Assert.Equal(540 - vm.ZoomState.Height / 2, vm.ZoomState.Y, 3);
            AssertTrueActiveLayer(vm);

            window.UpdateLayout();
            Assert.Null(zoomBox.Clip);
            Assert.Equal(Visibility.Collapsed, circleOutline.Visibility);
            Assert.Equal(Visibility.Visible, rectOutline.Visibility);

            // Tablet (horizontal rectangle): wide 16:9 box, click point is the CENTER.
            vm.ZoomShape = ZoomShape.HorizontalRectangle;
            vm.ActivateZoom(960, 540);
            Assert.True(vm.ZoomState.Width > vm.ZoomState.Height);
            Assert.Equal(16.0 / 9.0, vm.ZoomState.Width / vm.ZoomState.Height, 3);
            Assert.Equal(960 - vm.ZoomState.Width / 2, vm.ZoomState.X, 3);
            Assert.Equal(540 - vm.ZoomState.Height / 2, vm.ZoomState.Y, 3);
            AssertTrueActiveLayer(vm);

            // Clamp keeps the box fully inside the 1920x1080 preview even for a
            // corner click that would otherwise overhang it.
            vm.ActivateZoom(2000, 2000);
            const double frameW = 1920, frameH = 1080;
            Assert.True(vm.ZoomState.X >= 0 && vm.ZoomState.Y >= 0);
            Assert.True(vm.ZoomState.X + vm.ZoomState.Width <= frameW);
            Assert.True(vm.ZoomState.Y + vm.ZoomState.Height <= frameH);
            AssertTrueActiveLayer(vm);

            // The box is a composited layer, NEVER the crop: output stays the tier.
            var opts = vm.BuildCompositorOptions();
            Assert.True(opts.SourceRectWidth > vm.ZoomState.Width);
            Assert.Equal((int)Math.Round(vm.OutputRectWidth), opts.SourceRectWidth);
            Assert.Equal((int)Math.Round(vm.OutputRectHeight), opts.SourceRectHeight);

            // Dismiss restores the inert placeholder (Kind back to Static).
            vm.DismissZoom();
            Assert.False(vm.IsZoomActive);
            Assert.False(placeholder.IsZoomActive);
            Assert.False(placeholder.IsVisible);
            Assert.Equal(ElementKind.Static, placeholder.Kind);
        }
        finally
        {
            window.Close();
            MainViewModel.LayoutPathOverride = null;
            SqliteConnection.ClearAllPools();
            try { System.IO.File.Delete(tempDb); } catch { }
        }
    }

    private static void AssertTrueActiveLayer(MainViewModel vm)
    {
        var zoom = Assert.IsType<ZoomSceneElement>(vm.StagedScene!.Elements[1]);
        Assert.True(zoom.IsZoomActive);
        Assert.True(zoom.IsVisible);
        Assert.Equal(ElementKind.Dynamic, zoom.Kind);
        Assert.Equal(vm.ZoomState.X, zoom.X, 3);
        Assert.Equal(vm.ZoomState.Y, zoom.Y, 3);
        Assert.Equal(vm.ZoomState.Width, zoom.Width, 3);
        Assert.Equal(vm.ZoomState.Height, zoom.Height, 3);
        Assert.Equal(vm.ZoomShape == ZoomShape.Circle ? ClipShape.Round : ClipShape.Traditional, zoom.ClipShape);
    }
}