using System.IO;
using System.Security.Cryptography;
using System.Text;
using System.Windows;
using System.Runtime.InteropServices;
using System.Windows.Interop;
using QSafe.Core;

namespace QSafe.Desktop;

public partial class App : Application
{
    private Mutex? single;
    private bool ownsMutex;
    protected override void OnStartup(StartupEventArgs e)
    {
        base.OnStartup(e);
        bool smoke = e.Args.Contains("--smoke-test");
        bool demo = smoke || e.Args.Contains("--demo");
        var path = demo ? Path.Combine(Path.GetTempPath(), "QSafe-Demo", Guid.NewGuid().ToString("N")) : Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), "Kusoft", "QSafe");
        single = new Mutex(false, "Local\\QSafe-" + Convert.ToHexString(SHA256.HashData(Encoding.UTF8.GetBytes(path)))[..20]);
        try { ownsMutex = single.WaitOne(0); } catch (AbandonedMutexException) { ownsMutex = true; }
        if (!ownsMutex) { MessageBox.Show("QSafe уже запущен. Откройте существующее окно.", "QSafe"); Shutdown(); return; }
        try
        {
            var store = new LocalStore(path);
            int connectionIndex = Array.IndexOf(e.Args, "--connection");
            if (!demo && connectionIndex >= 0)
            {
                if (connectionIndex + 1 >= e.Args.Length) throw new InvalidDataException("Укажите личный файл локального подключения.");
                store.Configure(Connection.Parse(LocalStore.ReadBounded(e.Args[connectionIndex + 1], 65536)));
            }
            if (!demo && e.Args.Contains("--configure-only")) { Shutdown(); return; }
            MainWindow = new MainWindow(store, demo); MainWindow.Show();
            if (smoke)
            {
                var timer = new System.Windows.Threading.DispatcherTimer { Interval = TimeSpan.FromSeconds(2) };
                timer.Tick += (_, _) => { timer.Stop(); MainWindow.Close(); }; timer.Start();
            }
        }
        catch { MessageBox.Show("Не удалось открыть локальное хранилище или защищённые настройки. Данные не изменены. Проверьте доступ к папке %LOCALAPPDATA%\\Kusoft\\QSafe.", "QSafe", MessageBoxButton.OK, MessageBoxImage.Error); Shutdown(1); }
    }
    protected override void OnExit(ExitEventArgs e)
    {
        if (ownsMutex) single?.ReleaseMutex(); single?.Dispose(); base.OnExit(e);
    }
}

public static class NativeWindow
{
    [DllImport("dwmapi.dll")] private static extern int DwmSetWindowAttribute(IntPtr hwnd, int attribute, ref int value, int size);
    [DllImport("user32.dll")] [return: MarshalAs(UnmanagedType.Bool)] private static extern bool SetWindowDisplayAffinity(IntPtr hwnd, uint affinity);
    public static void Style(Window window)
    {
        window.SourceInitialized += (_, _) =>
        {
            var handle = new WindowInteropHelper(window).Handle; int dark = 1;
            DwmSetWindowAttribute(handle, 20, ref dark, sizeof(int));
            // Demo contains only synthetic credentials and can be captured for interface review.
            SetProtection(window, !(Application.Current.MainWindow is MainWindow main && main.IsDemo));
        };
    }
    public static void SetProtection(Window window, bool enabled)
    {
        var handle = new WindowInteropHelper(window).Handle;
        if (handle != IntPtr.Zero) SetWindowDisplayAffinity(handle, enabled ? 0x11u : 0u);
    }
}