using System;
using System.Runtime.InteropServices;
using System.Windows.Interop;

namespace Conjure.Arcade.Overlay
{
    public class HotkeyManager
    {
        [DllImport("user32.dll")]
        private static extern bool RegisterHotKey(IntPtr hWnd, int id, uint fsModifiers, uint vk);

        [DllImport("user32.dll")]
        private static extern bool UnregisterHotKey(IntPtr hWnd, int id);

        private const int HOTKEY_ID = 9000;
        private const uint MOD_ALT = 0x0001;
        private const uint MOD_CONTROL = 0x0002;

        private readonly IntPtr _windowHandle;
        private readonly Action _callback;

        public HotkeyManager(IntPtr windowHandle, Action callback)
        {
            _windowHandle = windowHandle;
            _callback = callback;
            ComponentDispatcher.ThreadPreprocessMessage += OnThreadPreprocessMessage;
        }

        public void Register()
        {
            // Register Ctrl+Alt+O as the hotkey
            RegisterHotKey(_windowHandle, HOTKEY_ID, MOD_CONTROL | MOD_ALT, 0x4F); // 0x4F is 'O'
        }

        public void Unregister()
        {
            UnregisterHotKey(_windowHandle, HOTKEY_ID);
            ComponentDispatcher.ThreadPreprocessMessage -= OnThreadPreprocessMessage;
        }

        private void OnThreadPreprocessMessage(ref MSG msg, ref bool handled)
        {
            if (msg.message == 0x0312 && msg.wParam.ToInt32() == HOTKEY_ID)
            {
                _callback();
                handled = true;
            }
        }
    }
}