using System;
using System.IO;
using Paca.Browser.Diagnostics;
using Paca.Browser.Media;
using Xunit;

namespace Paca.Tests.App;

public class DesktopMediaSpeedAndDiagnosticsGateTests
{
    private readonly string _mainWindowCsPath;
    private readonly string _mainWindowXamlPath;

    public DesktopMediaSpeedAndDiagnosticsGateTests()
    {
        var baseDir = AppContext.BaseDirectory;
        var solutionDir = Path.GetFullPath(Path.Combine(baseDir, "..", "..", "..", "..", ".."));
        _mainWindowCsPath = Path.Combine(solutionDir, "src", "Paca.App", "MainWindow.xaml.cs");
        _mainWindowXamlPath = Path.Combine(solutionDir, "src", "Paca.App", "MainWindow.xaml");
    }

    [Fact]
    public void Gate_MediaSpeedController_StepUpAndDown_ClampsWithinRange()
    {
        var controller = new MediaSpeedController();
        Assert.Equal(1.0, controller.CurrentSpeed);

        controller.StepUp();
        Assert.Equal(1.1, controller.CurrentSpeed);

        controller.StepDown();
        Assert.Equal(1.0, controller.CurrentSpeed);

        // Clamp to Max
        controller.SetSpeed(5.0);
        Assert.Equal(MediaSpeedController.MaxSpeed, controller.CurrentSpeed);

        // Clamp to Min
        controller.SetSpeed(0.1);
        Assert.Equal(MediaSpeedController.MinSpeed, controller.CurrentSpeed);

        // Script generation
        var script = controller.GeneratePlaybackScript();
        Assert.Contains("media.playbackRate", script);
        Assert.Contains("preservesPitch", script);
    }

    [Fact]
    public void Gate_VideoFrameCaptureCoordinator_GeneratesCaptureScriptAndSnapshots()
    {
        var coordinator = new VideoFrameCaptureCoordinator();

        // 1. Suggested filename
        var fileName = coordinator.GenerateSuggestedFileName("Test Video: Title/Sample", 45.5);
        Assert.StartsWith("PACA_Frame_Test Video_ Title_Sample_45.5s", fileName);
        Assert.EndsWith(".png", fileName);

        // 2. Aspect ratio
        Assert.Equal("16:9", VideoFrameCaptureCoordinator.CalculateAspectRatio(1920, 1080));
        Assert.Equal("16:10", VideoFrameCaptureCoordinator.CalculateAspectRatio(1920, 1200));
        Assert.Equal("4:3", VideoFrameCaptureCoordinator.CalculateAspectRatio(1024, 768));

        // 3. Snapshot PNG encoding
        var rawRgba = new byte[4 * 4 * 4]; // 4x4 RGBA
        Array.Fill(rawRgba, (byte)255);
        var meta = new VideoFrameMetadata("vid1", "Test", 4, 4, 1.0, 10.0, 30.0, DateTime.UtcNow);
        var snapshot = coordinator.CreateSnapshot(meta, rawRgba, 4, 4);

        Assert.NotNull(snapshot);
        Assert.True(snapshot.ImageData.Length > 8);
        // Verify PNG magic bytes: 0x89, 'P', 'N', 'G', 0x0D, 0x0A, 0x1A, 0x0A
        byte[] expectedMagic = { 0x89, 0x50, 0x4E, 0x47, 0x0D, 0x0A, 0x1A, 0x0A };
        for (int i = 0; i < expectedMagic.Length; i++)
        {
            Assert.Equal(expectedMagic[i], snapshot.ImageData[i]);
        }
    }

    [Fact]
    public void Gate_AdvancedProcessTaskInspector_ParsesProcessesAndCalculatesSummaries()
    {
        var inspector = new AdvancedProcessTaskInspector();

        // 1. Categorization
        Assert.Equal(BrowserProcessCategory.Browser, inspector.CategorizeProcess("Paca", null));
        Assert.Equal(BrowserProcessCategory.Gpu, inspector.CategorizeProcess("Paca", "--type=gpu-process"));
        Assert.Equal(BrowserProcessCategory.Renderer, inspector.CategorizeProcess("Paca", "--type=renderer"));
        Assert.Equal(BrowserProcessCategory.Utility, inspector.CategorizeProcess("Paca", "--type=utility"));
        Assert.Equal(BrowserProcessCategory.Audio, inspector.CategorizeProcess("Paca", "utility-sub-type=audio"));

        // 2. Register processes and aggregate
        inspector.RegisterProcess(new ProcessTaskSnapshot(1001, "Paca", BrowserProcessCategory.Browser, "Main", "", 150_000_000, 2.5));
        inspector.RegisterProcess(new ProcessTaskSnapshot(1002, "Paca", BrowserProcessCategory.Renderer, "Tab 1", "--type=renderer", 250_000_000, 5.0));

        Assert.Equal(400_000_000, inspector.GetTotalWorkingSetBytes());
        Assert.Equal(7.5, inspector.GetTotalCpuPercent());

        var summaries = inspector.GetCategorySummaries();
        Assert.Contains(summaries, s => s.Category == BrowserProcessCategory.Renderer && s.ProcessCount == 1);
    }

    [Fact]
    public void Gate_DesktopApp_MainWindow_HasMediaSpeedAndFrameCaptureWiring()
    {
        Assert.True(File.Exists(_mainWindowCsPath), "MainWindow.xaml.cs exists");
        var cs = File.ReadAllText(_mainWindowCsPath);

        // Core fields and properties
        Assert.Contains("MediaSpeedController", cs);
        Assert.Contains("VideoFrameCaptureCoordinator", cs);
        Assert.Contains("AdvancedProcessTaskInspector", cs);

        // Shortcut & Action methods
        Assert.Contains("AdjustMediaSpeed", cs);
        Assert.Contains("CaptureCurrentVideoFrame", cs);
        Assert.Contains("UpdateTaskManagerPanelSummary", cs);

        // Key bindings for '[' and ']'
        Assert.Contains("Key.OemOpenBrackets", cs);
        Assert.Contains("Key.OemCloseBrackets", cs);
    }
}