using System.Runtime.InteropServices;
using System.Windows.Controls.Primitives;
using System.Windows.Input;

namespace Melskin.Controls
{
    public class TrayIcon : FrameworkElement, IDisposable
    {
        // 1. 悬浮提示文本
        public static readonly DependencyProperty TipProperty =
            DependencyProperty.Register(nameof(Tip), typeof(string), typeof(TrayIcon),
                new PropertyMetadata(string.Empty, OnTextChanged));

        public string Tip
        {
            get => (string)GetValue(TipProperty);
            set => SetValue(TipProperty, value);
        }

        // 2. 双击命令
        public static readonly DependencyProperty DoubleClickCommandProperty =
            DependencyProperty.Register(nameof(DoubleClickCommand), typeof(ICommand), typeof(TrayIcon));

        public ICommand DoubleClickCommand
        {
            get => (ICommand)GetValue(DoubleClickCommandProperty);
            set => SetValue(DoubleClickCommandProperty, value);
        }

        public static readonly DependencyProperty ClickCommandProperty =
            DependencyProperty.Register(nameof(ClickCommand), typeof(ICommand), typeof(TrayIcon));

        public ICommand ClickCommand
        {
            get => (ICommand)GetValue(ClickCommandProperty);
            set => SetValue(ClickCommandProperty, value);
        }

        // 3. 【新增】图标本地路径 (例如: "app.ico")
        public static readonly DependencyProperty IconPathProperty =
            DependencyProperty.Register(nameof(IconPath), typeof(string), typeof(TrayIcon),
                new PropertyMetadata(string.Empty, OnIconPathChanged));

        public string IconPath
        {
            get => (string)GetValue(IconPathProperty);
            set => SetValue(IconPathProperty, value);
        }

        private static void OnTextChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            var ctrl = (TrayIcon)d;
            if (ctrl._isAdded)
            {
                ctrl._nid.szTip = e.NewValue?.ToString() ?? "";
                Shell_NotifyIcon(NIM_MODIFY, ref ctrl._nid);
            }
        }

        private static void OnIconPathChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
        {
            var ctrl = (TrayIcon)d;
            if (ctrl._isAdded)
            {
                ctrl._nid.hIcon = ctrl.LoadMyIcon(e.NewValue?.ToString());
                Shell_NotifyIcon(NIM_MODIFY, ref ctrl._nid);
            }
        }

        // --- Win32 API 声明 ---
        private const int NIM_ADD = 0x0000;
        private const int NIM_MODIFY = 0x0001;
        private const int NIM_DELETE = 0x0002;
        private const int NIF_MESSAGE = 0x0001;
        private const int NIF_ICON = 0x0002;
        private const int NIF_TIP = 0x0004;
        private const int WM_LBUTTONUP = 0x0202; // 左键弹起消息
        private const int WM_TRAYMOUSEMESSAGE = 0x0400 + 1024;
        private const int WM_LBUTTONDBLCLK = 0x0203;
        private const int WM_RBUTTONUP = 0x0205; [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
        private struct NOTIFYICONDATA
        {
            public int cbSize;
            public IntPtr hwnd;
            public int uID;
            public int uFlags;
            public int uCallbackMessage;
            public IntPtr hIcon; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 128)]
            public string szTip;
            public int dwState;
            public int dwStateMask; [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 256)]
            public string szInfo;
            public int uTimeoutOrVersion;
            [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 64)]
            public string szInfoTitle;
            public int dwInfoFlags;
            public Guid guidItem;
            public IntPtr hBalloonIcon;
        }
        [DllImport("shell32.dll", CharSet = CharSet.Unicode)]
        private static extern bool Shell_NotifyIcon(int dwMessage, ref NOTIFYICONDATA pnid);

        [DllImport("user32.dll")]
        [return: MarshalAs(UnmanagedType.Bool)]
        private static extern bool SetForegroundWindow(IntPtr hWnd);

        // 【新增】纯 Win32 加载本地图标 API
        [DllImport("user32.dll", CharSet = CharSet.Unicode)]
        private static extern IntPtr LoadImage(IntPtr hInst, string lpszName, uint uType, int cxDesired, int cyDesired, uint fuLoad);

        private IntPtr LoadMyIcon(string iconPath)
        {
            if (string.IsNullOrEmpty(iconPath)) return IntPtr.Zero;
            // 1 = IMAGE_ICON, 0x00000010 = LR_LOADFROMFILE
            return LoadImage(IntPtr.Zero, iconPath, 1, 0, 0, 0x00000010);
        }

        // --- 内部状态 ---
        private HwndSource _messageSink;
        private int _uID = 100;
        private bool _isAdded = false;
        private NOTIFYICONDATA _nid;

        public TrayIcon()
        {
            Visibility = Visibility.Collapsed;
            this.Loaded += OnLoaded;
            this.Unloaded += OnUnloaded;
            if (Application.Current != null)
                Application.Current.Exit += (s, e) => Dispose();
        }

        private void OnLoaded(object sender, RoutedEventArgs e)
        {
            if (_isAdded) return;

            HwndSourceParameters p = new HwndSourceParameters("TrayIconMessageSink")
            {
                Width = 0, Height = 0, WindowStyle = 0, ExtendedWindowStyle = 0x00000080
            };
            _messageSink = new HwndSource(p);
            _messageSink.AddHook(WndProc);

            _nid = new NOTIFYICONDATA
            {
                cbSize = Marshal.SizeOf(typeof(NOTIFYICONDATA)),
                hwnd = _messageSink.Handle,
                uID = _uID,
                uFlags = NIF_MESSAGE | NIF_TIP | NIF_ICON,
                uCallbackMessage = WM_TRAYMOUSEMESSAGE,
                szTip = this.Tip ?? "",
                // 加载属性中指定的图标
                hIcon = LoadMyIcon(this.IconPath)
            };

            Shell_NotifyIcon(NIM_ADD, ref _nid);
            _isAdded = true;
        }

        private IntPtr WndProc(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled)
        {
            if (msg == WM_TRAYMOUSEMESSAGE)
            {
                int mouseMsg = lParam.ToInt32();
                if (mouseMsg == WM_LBUTTONUP)
                {
                    if (ClickCommand?.CanExecute(null) == true)
                    {
                        ClickCommand.Execute(null);
                    }
                    handled = true;
                }
                else if (mouseMsg == WM_LBUTTONDBLCLK)
                {
                    if (DoubleClickCommand?.CanExecute(null) == true)
                        DoubleClickCommand.Execute(null);
                    handled = true;
                }
                else if (mouseMsg == WM_RBUTTONUP)
                {
                    ShowContextMenu();
                    handled = true;
                }
            }
            return IntPtr.Zero;
        }

        private void ShowContextMenu()
        {
            if (this.ContextMenu != null)
            {
                SetForegroundWindow(_messageSink.Handle);
                this.ContextMenu.PlacementTarget = null;
                this.ContextMenu.Placement = PlacementMode.MousePoint;
                this.ContextMenu.IsOpen = true;
            }
        }

        private void OnUnloaded(object sender, RoutedEventArgs e) => Dispose();

        public void Dispose()
        {
            if (_isAdded)
            {
                Shell_NotifyIcon(NIM_DELETE, ref _nid);
                _isAdded = false;
            }
            if (_messageSink != null)
            {
                _messageSink.RemoveHook(WndProc);
                _messageSink.Dispose();
                _messageSink = null;
            }
        }
    }
}