using OrpaonVision.Core.Abstractions;
using System.Windows;
using System.Windows.Threading;

namespace OrpaonVision.ConfigApp.Infrastructure.Diagnostics;

/// <summary>
/// 全局未处理异常捕获器。
/// </summary>
public sealed class GlobalExceptionHandler : IDisposable
{
    private readonly IAppLogger _logger;

    private bool _registered;

    /// <summary>
    /// 构造全局异常处理器。
    /// </summary>
    /// <param name="logger">日志记录器。</param>
    public GlobalExceptionHandler(IAppLogger logger)
    {
        _logger = logger;
    }

    /// <summary>
    /// 注册全局异常事件。
    /// </summary>
    public void Register()
    {
        if (_registered)
        {
            return;
        }

        Application.Current.DispatcherUnhandledException += OnDispatcherUnhandledException;
        AppDomain.CurrentDomain.UnhandledException += OnUnhandledException;
        TaskScheduler.UnobservedTaskException += OnUnobservedTaskException;
        _registered = true;
    }

    /// <summary>
    /// 注销全局异常事件。
    /// </summary>
    public void Dispose()
    {
        if (!_registered)
        {
            return;
        }

        Application.Current.DispatcherUnhandledException -= OnDispatcherUnhandledException;
        AppDomain.CurrentDomain.UnhandledException -= OnUnhandledException;
        TaskScheduler.UnobservedTaskException -= OnUnobservedTaskException;
        _registered = false;
    }

    private void OnDispatcherUnhandledException(object sender, DispatcherUnhandledExceptionEventArgs e)
    {
        var traceId = CreateTraceId();
        _logger.LogError("捕获到 UI 线程未处理异常。", e.Exception, traceId);

        MessageBox.Show(
            $"程序发生未处理异常，操作已中断。{Environment.NewLine}TraceId: {traceId}",
            "OrpaonVision.ConfigApp",
            MessageBoxButton.OK,
            MessageBoxImage.Error);

        e.Handled = true;
    }

    private void OnUnhandledException(object? sender, UnhandledExceptionEventArgs e)
    {
        var traceId = CreateTraceId();
        var exception = e.ExceptionObject as Exception;

        _logger.LogError("捕获到应用域未处理异常。", exception, traceId);
    }

    private void OnUnobservedTaskException(object? sender, UnobservedTaskExceptionEventArgs e)
    {
        var traceId = CreateTraceId();
        _logger.LogError("捕获到未观察的任务异常。", e.Exception, traceId);
        e.SetObserved();
    }

    private static string CreateTraceId()
    {
        return Guid.NewGuid().ToString("N");
    }
}