using System;
using System.Linq;
using Xunit;
using ytLive.Models;
using ytLive.Services;
using ytLive.ViewModels;

namespace ytLive.Tests;

/// <summary>
/// A scene switch in edit mode raises the preview transition with the chosen type and
/// length, before the staged scene changes, so the preview can animate the old picture.
/// </summary>
[Collection("RealApp")]
public sealed class PreviewTransitionTests
{
    private readonly RealAppHost _app;

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

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

    private static void Run()
    {
        var tempDb = System.IO.Path.Combine(System.IO.Path.GetTempPath(), $"ytLlive-preview-{Guid.NewGuid():N}.db");
        MainViewModel.LayoutPathOverride = tempDb;
        try
        {
            using (var schema = new LayoutStore(tempDb)) { }
            Microsoft.Data.Sqlite.SqliteConnection.ClearAllPools();

            var vm = new MainViewModel();
            var from = vm.StagedScene!;
            var to = vm.Scenes.First(s => s != from && !s.IsHidden);
            vm.SelectedTransitionType = TransitionType.Fade;
            vm.TransitionDurationMs = 800;

            Scene? stagedWhenRaised = null;
            TransitionType? typeRaised = null;
            double? msRaised = null;
            vm.PreviewTransition += (type, ms) =>
            {
                stagedWhenRaised = vm.StagedScene;
                typeRaised = type;
                msRaised = ms;
            };

            vm.TransitionToScene(to);

            Assert.Same(from, stagedWhenRaised);
            Assert.Equal(TransitionType.Fade, typeRaised);
            Assert.Equal(800, msRaised);
            Assert.Same(to, vm.StagedScene);
        }
        finally
        {
            MainViewModel.LayoutPathOverride = null;
            Microsoft.Data.Sqlite.SqliteConnection.ClearAllPools();
            try { System.IO.File.Delete(tempDb); } catch { }
        }
    }
}