using System.IO;
using System.Threading.Tasks;
using Microsoft.Data.Sqlite;
using Xunit;
using ytLive.Services.Audio;
using ytLive.ViewModels;

namespace ytLive.Tests;

/// <summary>2026-10-09 bug: pressing TRAX started the music but the status light stayed off —
/// and the toggle couldn't pause, because the playing state was never refreshed after Play.
/// TRAX is a toggle: the light is green while playing, red with a terse scrolling message on
/// failure, gray when idle.</summary>
[Collection("RealApp")]
public sealed class TraxToggleTests
{
    private sealed class FakePlayer : ITraxPlayer
    {
        public bool Starts = true;
        public event Action<Exception?>? PlaybackEnded;
        public string? TrackName { get; private set; }
        public bool IsPlaying { get; private set; }
        public float LocalGain { get; set; } = 1f;
        public float UserGain { get; set; } = 1f;
        public void Load(string path) => TrackName = Path.GetFileNameWithoutExtension(path);
        public void Play() => IsPlaying = Starts;
        public void Pause() => IsPlaying = false;
        public void Dispose() { }
        public void Fail() { IsPlaying = false; PlaybackEnded?.Invoke(new IOException("device lost")); }
    }

    private readonly RealAppHost _app;
    public TraxToggleTests(RealAppHost app) => _app = app;

    [Fact]
    public async Task Trax_Toggle_Lights_Green_While_Playing_And_Red_With_A_Terse_Error()
    {
        await _app.RunAsync(async () =>
        {
            var tempDb = Path.Combine(Path.GetTempPath(), $"ytLlive-test-{Guid.NewGuid():N}.db");
            var track = Path.Combine(Path.GetTempPath(), $"trax-{Guid.NewGuid():N}.mp3");
            File.WriteAllBytes(track, new byte[16]);
            var player = new FakePlayer();
            MainViewModel.LayoutPathOverride = tempDb;
            MainViewModel.TraxPlayerOverride = () => player;
            var window = new MainWindow();
            var vm = (MainViewModel)window.DataContext;
            try
            {
                await vm.SetTraxTrackAsync(track, play: false);
                Assert.False(vm.IsMusicPlaying);
                var idle = vm.TraxDotBrush.Color;

                vm.TraxLeftClick();                                   // press: plays → light on
                Assert.True(vm.IsMusicPlaying);
                var playing = vm.TraxDotBrush.Color;
                Assert.NotEqual(idle, playing);
                Assert.Null(vm.TraxError);

                vm.TraxLeftClick();                                   // press again: pauses → light off
                Assert.False(vm.IsMusicPlaying);
                Assert.Equal(idle, vm.TraxDotBrush.Color);

                player.Starts = false;                                // press: playback can't start
                vm.TraxLeftClick();
                Assert.False(vm.IsMusicPlaying);
                Assert.NotNull(vm.TraxError);
                Assert.True(vm.TraxError!.Length <= 32, $"error not terse: '{vm.TraxError}'");
                var red = vm.TraxDotBrush.Color;
                Assert.NotEqual(idle, red);
                Assert.NotEqual(playing, red);

                player.Starts = true;                                 // recovery clears the error
                vm.TraxLeftClick();
                Assert.True(vm.IsMusicPlaying);
                Assert.Null(vm.TraxError);
                Assert.Equal(playing, vm.TraxDotBrush.Color);

                player.Fail();                                        // device lost mid-play
                Assert.False(vm.IsMusicPlaying);
                Assert.Equal(red, vm.TraxDotBrush.Color);
            }
            finally
            {
                window.Close();
                MainViewModel.LayoutPathOverride = null;
                MainViewModel.TraxPlayerOverride = null;
                SqliteConnection.ClearAllPools();
                try { File.Delete(tempDb); File.Delete(track); } catch { /* best-effort cleanup */ }
            }
        });
    }
}