using System.Windows;
using System.Windows.Controls;
using System.Windows.Media.Imaging;
using Xunit;
using ytLive.Models;
using ytLive.Services;

namespace ytLive.Tests;

[Collection("RealApp")]
public sealed class TextOverlayRendererTests
{
    private readonly RealAppHost _app;

    public TextOverlayRendererTests(RealAppHost app) => _app = app;

    [Fact]
    public void Raster_IsCached_And_PreviewBitmap_Uses_The_Same_Transparent_Pixels()
    {
        _app.Run(() =>
        {
            var source = new Source
            {
                Type = SourceType.TextOverlay,
                TextContent = "Cached text",
                Width = 220,
                Height = 70,
                TextFontSize = 36,
                TextColor = "#80FFFFFF",
                TextBold = true,
                TextUnderline = true,
            };
            var renderer = new TextOverlayRenderer();
            renderer.UpdatePreview(source);

            var first = Assert.IsType<VideoFrame>(renderer.RenderFrame(source));
            var preview = Assert.IsType<WriteableBitmap>(source.VideoImageSource);
            var pixels = new byte[first.BgraPixels.Length];
            preview.CopyPixels(pixels, first.Stride, 0);
            Assert.Equal(first.BgraPixels, pixels);
            Assert.Contains(first.BgraPixels.Where((_, index) => index % 4 == 3), alpha => alpha > 0);
            Assert.Contains(first.BgraPixels.Where((_, index) => index % 4 == 3), alpha => alpha == 0);

            renderer.UpdatePreview(source);
            Assert.Same(first, renderer.RenderFrame(source));
            Assert.Same(preview, source.VideoImageSource);

            source.TextContent = "Changed";
            renderer.UpdatePreview(source);
            Assert.NotSame(first, renderer.RenderFrame(source));
            Assert.NotSame(preview, source.VideoImageSource);
        });
    }
}