using System;
using System.Threading;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using Notification.Core;
using Notification.Wpf.Controls;
using Xunit;
using ytLive.Services;

namespace ytLive.Tests;

/// <summary>
/// TASK 24 integration: the real NotificationService against a real window-hosted
/// ToastArea. Transient notifications expire on their own; errors stick until the
/// area goes away. ONE integration test per the Good Dog Rule.
/// </summary>
[Collection("RealApp")]
public class NotificationAreaIntegrationTests
{
    private readonly RealAppHost _app;

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

    [Fact]
    public void Info_Auto_Dismisses_And_Error_Sticks()
    {
        Window? window = null;
        NotificationArea? area = null;
        NotificationService? service = null;
        _app.Run(() =>
        {
            area = new NotificationArea { Name = NotificationService.AreaName, Position = NotificationPosition.BottomRight, MaxItems = 4 };
            var grid = new Grid();
            grid.Children.Add(area);
            window = new Window { Content = grid, Width = 400, Height = 300, WindowStartupLocation = WindowStartupLocation.Manual, Left = -32000, Top = 0, ShowInTaskbar = false, ShowActivated = false };
            window.Show();
            service = new NotificationService();
        });

        try
        {
            service!.Info("Hello", "transient");
            Assert.True(WaitFor(() => ItemCount(area!) == 1), "info toast never appeared");

            Assert.True(WaitFor(() => ItemCount(area!) == 0, TimeSpan.FromSeconds(8)),
                "info toast never auto-dismissed");

            service!.Error("Broken", "sticky");
            Assert.True(WaitFor(() => ItemCount(area!) == 1), "error toast never appeared");

            Thread.Sleep(1200);
            Assert.Equal(1, ItemCount(area!));
        }
        finally
        {
            _app.Run(() => window!.Close());
        }
    }

    private int ItemCount(NotificationArea area)
    {
        var count = 0;
        _app.Run(() => count = CountItems(area));
        return count;
    }

    private static int CountItems(NotificationArea area)
    {
        var count = 0;
        Walk(area, ref count);
        return count;

        static void Walk(DependencyObject node, ref int count)
        {
            if (node is Panel panel && panel.Name == "PART_Items")
            {
                count += panel.Children.Count;
                return;
            }
            for (var i = 0; i < VisualTreeHelper.GetChildrenCount(node); i++)
                Walk(VisualTreeHelper.GetChild(node, i), ref count);
        }
    }

    private static bool WaitFor(Func<bool> condition, TimeSpan? timeout = null)
    {
        var deadline = DateTime.UtcNow + (timeout ?? TimeSpan.FromSeconds(3));
        while (DateTime.UtcNow < deadline)
        {
            if (condition()) return true;
            Thread.Sleep(50);
        }
        return condition();
    }
}