using System.IO;
using System.Windows;
using System.Windows.Threading;
using VideoDownloader.App.Core;

namespace VideoDownloader.App;

public partial class App : Application
{
    private static string CrashLogPath => Path.Combine(
        Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData), "VideoDownloader", "crash.log");

    // #14 글로벌 예외 핸들러: 잡히지 않은 예외를 crash.log 에 기록해 조용히 삼켜지는 것을 방지.
    protected override void OnStartup(StartupEventArgs e)
    {
        DispatcherUnhandledException += (_, de) => { LogCrash(de.Exception); de.Handled = true; };
        AppDomain.CurrentDomain.UnhandledException += (_, ue) => LogCrash(ue.ExceptionObject as Exception);
        TaskScheduler.UnobservedTaskException += (_, ue) => { LogCrash(ue.Exception); ue.SetObserved(); };
        base.OnStartup(e);

        ApplyTheme(ConfigStore.Load().Theme);
        new MainWindow().Show();
    }

    /// <summary>테마 색(dark/light) + Shared(스타일) 리소스사전을 App.Resources 에 주입.
    /// 주의: 반드시 색(brush) 사전을 스타일 사전보다 먼저 로드해야 Shared 의 템플릿이
    /// {StaticResource GlassBg} 등을 해석할 수 있다.</summary>
    public static void ApplyTheme(string theme)
    {
        var dicts = Current.Resources.MergedDictionaries;
        dicts.Clear();
        var themeSrc = theme.Equals("light", StringComparison.OrdinalIgnoreCase)
            ? "pack://application:,,,/Themes/Light.xaml" : "pack://application:,,,/Themes/Dark.xaml";
        dicts.Add(new ResourceDictionary { Source = new Uri(themeSrc, UriKind.Absolute) });
        dicts.Add(new ResourceDictionary { Source = new Uri("pack://application:,,,/Themes/Shared.xaml", UriKind.Absolute) });
    }

    /// <summary>현재 적용된 테마가 라이트인지 (DWM 타이틀바 색 연동용).</summary>
    public static bool IsLightTheme => ConfigStore.Load().Theme.Equals("light", StringComparison.OrdinalIgnoreCase);

    private static void LogCrash(Exception? ex)
    {
        if (ex == null) return;
        try
        {
            var dir = Path.GetDirectoryName(CrashLogPath);
            if (!string.IsNullOrEmpty(dir)) Directory.CreateDirectory(dir);
            File.AppendAllText(CrashLogPath,
                $"[{DateTime.Now:yyyy-MM-dd HH:mm:ss}] {ex}{Environment.NewLine}{new string('-', 60)}{Environment.NewLine}");
        }
        catch { }
    }
}