using System;
using System.IO;
using System.Linq;
using Microsoft.Data.Sqlite;
using Xunit;
using ytLive.Models;
using ytLive.ViewModels;

namespace ytLive.Tests;

/// <summary>
/// TASK 27 integration: the (+) menu's YouTube Chat row gates on one chat layer
/// per layout (same rule as the webcam's app-wide identity), and ChatBox layers
/// created before the "YouTube Chat" default (legacy name "Chat") heal to the
/// picklist's label on load — creator renames stay untouched.
/// Real-App + temp-DB pattern (see WebcamMenuGateTests).
/// </summary>
[Collection("RealApp")]
public sealed class ChatLayerGateTests
{
    [Fact]
    public void LegacyChatName_Heals_And_CanAddYouTubeChat_Gates_On_The_Existing_Layer()
    {
        _app.Run(Run);
    }

    private readonly RealAppHost _app;

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

    private void Run()
    {
        var tempDb = Path.Combine(Path.GetTempPath(), $"ytLlive-chatgate-{Guid.NewGuid():N}.db");
        MainViewModel.LayoutPathOverride = tempDb;
        var window = default(MainWindow);
        try
        {
            using (var schema = new ytLive.Services.LayoutStore(tempDb)) { }
            SqliteConnection.ClearAllPools();
            SeedDatabaseWithLegacyChatLayer(tempDb);

            window = new MainWindow();
            var vm = (MainViewModel)window.DataContext;

            var starting = vm.Scenes.Single(s => SceneCatalog.Is(s.Name, SceneCatalog.Starting));
            var live = vm.Scenes.Single(s => SceneCatalog.Is(s.Name, SceneCatalog.Live));

            var chatLayer = Assert.Single(starting.Elements.OfType<Source>()
                .Where(s => s.Type == SourceType.ChatBox).ToList());
            Assert.Equal("YouTube Chat", chatLayer.Name);

            vm.StagedScene = live;
            Assert.False(vm.CanAddYouTubeChat,
                "chat layer exists in another scene — Add YouTube Chat must be greyed out");

            vm.StagedScene = starting;
            Assert.False(vm.CanAddYouTubeChat, "staged scene itself has the chat layer");

            vm.SaveLayoutNow();
            using (var connection = new SqliteConnection($"Data Source={tempDb}"))
            {
                connection.Open();
                using var names = connection.CreateCommand();
                names.CommandText =
                    "SELECT Name FROM Source WHERE Type = 'ChatBox';";
                Assert.Equal("YouTube Chat", (string)names.ExecuteScalar()!);
            }

            vm.RemoveSourceCommand.Execute(chatLayer);
            Assert.True(vm.CanAddYouTubeChat,
                "the only chat layer was removed — the (+) item re-enables");
        }
        finally
        {
            window?.Close();
            MainViewModel.LayoutPathOverride = null;
            SqliteConnection.ClearAllPools();
            try { File.Delete(tempDb); } catch { /* best-effort cleanup */ }
        }
    }

    /// <summary>Five canonical scenes + a ChatBox layer still carrying the
    /// pre-rename default name "Chat" in Starting.</summary>
    private static void SeedDatabaseWithLegacyChatLayer(string path)
    {
        using var connection = new SqliteConnection($"Data Source={path}");
        connection.Open();

        var scenes = new (string Id, string Name)[]
        {
            ("scene-starting", "Starting"),
            ("scene-live", "Live"),
            ("scene-brb", "BRB"),
            ("scene-chat", "Chat"),
            ("scene-ending", "Ending"),
        };
        foreach (var (id, name) in scenes)
        {
            using var cmd = connection.CreateCommand();
            cmd.CommandText =
                "INSERT INTO Scene (Id, Name, HasBackground, SortOrder) VALUES ($id, $name, 1, $order);";
            cmd.Parameters.AddWithValue("$id", id);
            cmd.Parameters.AddWithValue("$name", name);
            cmd.Parameters.AddWithValue("$order", Array.IndexOf(scenes, (id, name)));
            cmd.ExecuteNonQuery();
        }

        using (var background = connection.CreateCommand())
        {
            background.CommandText =
                @"INSERT INTO Source (Id, SceneId, Type, Name, IsEnabled, X, Y, Width, Height, IsBackground, SortOrder)
                  VALUES ('bg-1', 'scene-starting', 'Background', 'Background', 1, 0, 0, 1920, 1080, 1, 0);";
            background.ExecuteNonQuery();
        }

        using (var chat = connection.CreateCommand())
        {
            chat.CommandText =
                @"INSERT INTO Source (Id, SceneId, Type, Name, IsEnabled, X, Y, Width, Height, IsBackground, SortOrder)
                  VALUES ('chat-1', 'scene-starting', 'ChatBox', 'Chat', 1, 1400, 20, 500, 648, 0, 1);";
            chat.ExecuteNonQuery();
        }
    }
}