using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading.Tasks;

namespace KeyMon
{
    public class LowLevelKeyMonitor
    {

        #region WinAPI Constants
        public enum MouseMessages
        {
            WM_MOUSEMOVE = 0x0200,
            WM_MOUSEWHEEL = 0x020A,
        }

        public enum VKeys
        {
            // Losely based on http://www.pinvoke.net/default.aspx/Enums/VK.html

            // LBUTTON = 0x01,     // Left mouse button
            // RBUTTON = 0x02,     // Right mouse button
            CANCEL = 0x03,      // Control-break processing
            MBUTTON = 0x04,     // Middle mouse button (three-button mouse)
            XBUTTON1 = 0x05,    // Windows 2000/XP: X1 mouse button
            XBUTTON2 = 0x06,    // Windows 2000/XP: X2 mouse button
            //                  0x07   // Undefined
            BACK = 0x08,        // BACKSPACE key
            TAB = 0x09,         // TAB key
            //                  0x0A-0x0B,  // Reserved
            CLEAR = 0x0C,       // CLEAR key
            RETURN = 0x0D,      // ENTER key
            //                  0x0E-0x0F, // Undefined
            SHIFT = 0x10,       // SHIFT key
            CONTROL = 0x11,     // CTRL key
            MENU = 0x12,        // ALT key
            PAUSE = 0x13,       // PAUSE key
            CAPITAL = 0x14,     // CAPS LOCK key
            KANA = 0x15,        // Input Method Editor (IME) Kana mode
            HANGUL = 0x15,      // IME Hangul mode
            //                  0x16,  // Undefined
            JUNJA = 0x17,       // IME Junja mode
            FINAL = 0x18,       // IME final mode
            HANJA = 0x19,       // IME Hanja mode
            KANJI = 0x19,       // IME Kanji mode
            //                  0x1A,  // Undefined
            ESCAPE = 0x1B,      // ESC key
            CONVERT = 0x1C,     // IME convert
            NONCONVERT = 0x1D,  // IME nonconvert
            ACCEPT = 0x1E,      // IME accept
            MODECHANGE = 0x1F,  // IME mode change request
            SPACE = 0x20,       // SPACEBAR
            PRIOR = 0x21,       // PAGE UP key
            NEXT = 0x22,        // PAGE DOWN key
            END = 0x23,         // END key
            HOME = 0x24,        // HOME key
            LEFT = 0x25,        // LEFT ARROW key
            UP = 0x26,          // UP ARROW key
            RIGHT = 0x27,       // RIGHT ARROW key
            DOWN = 0x28,        // DOWN ARROW key
            SELECT = 0x29,      // SELECT key
            PRINT = 0x2A,       // PRINT key
            EXECUTE = 0x2B,     // EXECUTE key
            SNAPSHOT = 0x2C,    // PRINT SCREEN key
            INSERT = 0x2D,      // INS key
            DELETE = 0x2E,      // DEL key
            HELP = 0x2F,        // HELP key
            KEY_0 = 0x30,       // 0 key
            KEY_1 = 0x31,       // 1 key
            KEY_2 = 0x32,       // 2 key
            KEY_3 = 0x33,       // 3 key
            KEY_4 = 0x34,       // 4 key
            KEY_5 = 0x35,       // 5 key
            KEY_6 = 0x36,       // 6 key
            KEY_7 = 0x37,       // 7 key
            KEY_8 = 0x38,       // 8 key
            KEY_9 = 0x39,       // 9 key
            //                  0x3A-0x40, // Undefined
            KEY_A = 0x41,       // A key
            KEY_B = 0x42,       // B key
            KEY_C = 0x43,       // C key
            KEY_D = 0x44,       // D key
            KEY_E = 0x45,       // E key
            KEY_F = 0x46,       // F key
            KEY_G = 0x47,       // G key
            KEY_H = 0x48,       // H key
            KEY_I = 0x49,       // I key
            KEY_J = 0x4A,       // J key
            KEY_K = 0x4B,       // K key
            KEY_L = 0x4C,       // L key
            KEY_M = 0x4D,       // M key
            KEY_N = 0x4E,       // N key
            KEY_O = 0x4F,       // O key
            KEY_P = 0x50,       // P key
            KEY_Q = 0x51,       // Q key
            KEY_R = 0x52,       // R key
            KEY_S = 0x53,       // S key
            KEY_T = 0x54,       // T key
            KEY_U = 0x55,       // U key
            KEY_V = 0x56,       // V key
            KEY_W = 0x57,       // W key
            KEY_X = 0x58,       // X key
            KEY_Y = 0x59,       // Y key
            KEY_Z = 0x5A,       // Z key
            LWIN = 0x5B,        // Left Windows key (Microsoft Natural keyboard)
            RWIN = 0x5C,        // Right Windows key (Natural keyboard)
            APPS = 0x5D,        // Applications key (Natural keyboard)
            //                  0x5E, // Reserved
            SLEEP = 0x5F,       // Computer Sleep key
            NUMPAD0 = 0x60,     // Numeric keypad 0 key
            NUMPAD1 = 0x61,     // Numeric keypad 1 key
            NUMPAD2 = 0x62,     // Numeric keypad 2 key
            NUMPAD3 = 0x63,     // Numeric keypad 3 key
            NUMPAD4 = 0x64,     // Numeric keypad 4 key
            NUMPAD5 = 0x65,     // Numeric keypad 5 key
            NUMPAD6 = 0x66,     // Numeric keypad 6 key
            NUMPAD7 = 0x67,     // Numeric keypad 7 key
            NUMPAD8 = 0x68,     // Numeric keypad 8 key
            NUMPAD9 = 0x69,     // Numeric keypad 9 key
            MULTIPLY = 0x6A,    // Multiply key
            ADD = 0x6B,         // Add key
            SEPARATOR = 0x6C,   // Separator key
            SUBTRACT = 0x6D,    // Subtract key
            DECIMAL = 0x6E,     // Decimal key
            DIVIDE = 0x6F,      // Divide key
            F1 = 0x70,          // F1 key
            F2 = 0x71,          // F2 key
            F3 = 0x72,          // F3 key
            F4 = 0x73,          // F4 key
            F5 = 0x74,          // F5 key
            F6 = 0x75,          // F6 key
            F7 = 0x76,          // F7 key
            F8 = 0x77,          // F8 key
            F9 = 0x78,          // F9 key
            F10 = 0x79,         // F10 key
            F11 = 0x7A,         // F11 key
            F12 = 0x7B,         // F12 key
            F13 = 0x7C,         // F13 key
            F14 = 0x7D,         // F14 key
            F15 = 0x7E,         // F15 key
            F16 = 0x7F,         // F16 key
            F17 = 0x80,         // F17 key
            F18 = 0x81,         // F18 key
            F19 = 0x82,         // F19 key
            F20 = 0x83,         // F20 key
            F21 = 0x84,         // F21 key
            F22 = 0x85,         // F22 key, (PPC only) Key used to lock device.
            F23 = 0x86,         // F23 key
            F24 = 0x87,         // F24 key
            //                  0x88-0X8F,  // Unassigned
            NUMLOCK = 0x90,     // NUM LOCK key
            SCROLL = 0x91,      // SCROLL LOCK key
            //                  0x92-0x96,  // OEM specific
            //                  0x97-0x9F,  // Unassigned
            LSHIFT = 0xA0,      // Left SHIFT key
            RSHIFT = 0xA1,      // Right SHIFT key
            LCONTROL = 0xA2,    // Left CONTROL key
            RCONTROL = 0xA3,    // Right CONTROL key
            LMENU = 0xA4,       // Left MENU key
            RMENU = 0xA5,       // Right MENU key
            BROWSER_BACK = 0xA6,    // Windows 2000/XP: Browser Back key
            BROWSER_FORWARD = 0xA7, // Windows 2000/XP: Browser Forward key
            BROWSER_REFRESH = 0xA8, // Windows 2000/XP: Browser Refresh key
            BROWSER_STOP = 0xA9,    // Windows 2000/XP: Browser Stop key
            BROWSER_SEARCH = 0xAA,  // Windows 2000/XP: Browser Search key
            BROWSER_FAVORITES = 0xAB,  // Windows 2000/XP: Browser Favorites key
            BROWSER_HOME = 0xAC,    // Windows 2000/XP: Browser Start and Home key
            VOLUME_MUTE = 0xAD,     // Windows 2000/XP: Volume Mute key
            VOLUME_DOWN = 0xAE,     // Windows 2000/XP: Volume Down key
            VOLUME_UP = 0xAF,  // Windows 2000/XP: Volume Up key
            MEDIA_NEXT_TRACK = 0xB0,// Windows 2000/XP: Next Track key
            MEDIA_PREV_TRACK = 0xB1,// Windows 2000/XP: Previous Track key
            MEDIA_STOP = 0xB2, // Windows 2000/XP: Stop Media key
            MEDIA_PLAY_PAUSE = 0xB3,// Windows 2000/XP: Play/Pause Media key
            LAUNCH_MAIL = 0xB4,     // Windows 2000/XP: Start Mail key
            LAUNCH_MEDIA_SELECT = 0xB5,  // Windows 2000/XP: Select Media key
            LAUNCH_APP1 = 0xB6,     // Windows 2000/XP: Start Application 1 key
            LAUNCH_APP2 = 0xB7,     // Windows 2000/XP: Start Application 2 key
            //                  0xB8-0xB9,  // Reserved
            OEM_1 = 0xBA,       // Used for miscellaneous characters; it can vary by keyboard.
            // Windows 2000/XP: For the US standard keyboard, the ';:' key
            OEM_PLUS = 0xBB,    // Windows 2000/XP: For any country/region, the '+' key
            OEM_COMMA = 0xBC,   // Windows 2000/XP: For any country/region, the ',' key
            OEM_MINUS = 0xBD,   // Windows 2000/XP: For any country/region, the '-' key
            OEM_PERIOD = 0xBE,  // Windows 2000/XP: For any country/region, the '.' key
            OEM_2 = 0xBF,       // Used for miscellaneous characters; it can vary by keyboard.
            // Windows 2000/XP: For the US standard keyboard, the '/?' key
            OEM_3 = 0xC0,       // Used for miscellaneous characters; it can vary by keyboard.
            // Windows 2000/XP: For the US standard keyboard, the '`~' key
            //                  0xC1-0xD7,  // Reserved
            //                  0xD8-0xDA,  // Unassigned
            OEM_4 = 0xDB,       // Used for miscellaneous characters; it can vary by keyboard.
            // Windows 2000/XP: For the US standard keyboard, the '[{' key
            OEM_5 = 0xDC,       // Used for miscellaneous characters; it can vary by keyboard.
            // Windows 2000/XP: For the US standard keyboard, the '\|' key
            OEM_6 = 0xDD,       // Used for miscellaneous characters; it can vary by keyboard.
            // Windows 2000/XP: For the US standard keyboard, the ']}' key
            OEM_7 = 0xDE,       // Used for miscellaneous characters; it can vary by keyboard.
            // Windows 2000/XP: For the US standard keyboard, the 'single-quote/double-quote' key
            OEM_8 = 0xDF,       // Used for miscellaneous characters; it can vary by keyboard.
            //                  0xE0,  // Reserved
            //                  0xE1,  // OEM specific
            OEM_102 = 0xE2,     // Windows 2000/XP: Either the angle bracket key or the backslash key on the RT 102-key keyboard
            //                  0xE3-E4,  // OEM specific
            PROCESSKEY = 0xE5,  // Windows 95/98/Me, Windows NT 4.0, Windows 2000/XP: IME PROCESS key
            //                  0xE6,  // OEM specific
            PACKET = 0xE7,      // Windows 2000/XP: Used to pass Unicode characters as if they were keystrokes. The VK_PACKET key is the low word of a 32-bit Virtual Key value used for non-keyboard input methods. For more information, see Remark in KEYBDINPUT, SendInput, WM_KEYDOWN, and WM_KEYUP
            //                  0xE8,  // Unassigned
            //                  0xE9-F5,  // OEM specific
            ATTN = 0xF6,        // Attn key
            CRSEL = 0xF7,       // CrSel key
            EXSEL = 0xF8,       // ExSel key
            EREOF = 0xF9,       // Erase EOF key
            PLAY = 0xFA,        // Play key
            ZOOM = 0xFB,        // Zoom key
            NONAME = 0xFC,      // Reserved
            PA1 = 0xFD,         // PA1 key
            OEM_CLEAR = 0xFE    // Clear key
        }

        private const int WM_KEYDOWN = 0x100;
        private const int WM_SYSKEYDOWN = 0x104;
        private const int WM_KEYUP = 0x101;
        private const int WM_SYSKEYUP = 0x105;


        private const int WH_KEYBOARD_LL = 13;
        private const int WH_MOUSE_LL = 14;


        #endregion
        #region WinAPI

        [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
        private static extern IntPtr SetWindowsHookEx(int idHook, HookHandler lpfn, IntPtr hMod, uint dwThreadId);

        [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
        [return: MarshalAs(UnmanagedType.Bool)]
        private static extern bool UnhookWindowsHookEx(IntPtr hhk);

        [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
        private static extern IntPtr CallNextHookEx(IntPtr hhk, int nCode, IntPtr wParam, IntPtr lParam);

        [DllImport("kernel32.dll", CharSet = CharSet.Auto, SetLastError = true)]
        private static extern IntPtr GetModuleHandle(string lpModuleName);



        #endregion

        public delegate void KeyCallback(VKeys key);
        public event KeyCallback KeyboardEvent;
        public event KeyCallback MouseEvent;

        private delegate IntPtr HookHandler(int nCode, IntPtr wParam, IntPtr lParam);
        private HookHandler k_hookHandler;
        private HookHandler m_hookHandler;

        private IntPtr k_hookID = IntPtr.Zero;
        private IntPtr m_hookID = IntPtr.Zero;


        public LowLevelKeyMonitor()
        {
            k_hookHandler = KeyboardHookFunction;
            m_hookHandler = MouseHookFunction;

            k_hookID = SetKeyboardHook(k_hookHandler);
            m_hookID = SetMouseHook(m_hookHandler);

        }

        public void Die(object sender, EventArgs e)
        {
            UnhookWindowsHookEx(k_hookID);
            UnhookWindowsHookEx(m_hookID);
        }

        public IntPtr MouseHookFunction(int nCode, IntPtr wParam, IntPtr lParam)
        {
            File.WriteAllText("KeyMon.log",File.ReadAllText("KeyMon.log")+"\n Mouse Event Fired!");


            return CallNextHookEx(m_hookID, nCode, wParam, lParam);
        }

        public IntPtr KeyboardHookFunction(int nCode, IntPtr wParam, IntPtr lParam)
        {
            File.WriteAllText("KeyMon.log", File.ReadAllText("KeyMon.log") + "\n Keyboard Event Fired!");



            return CallNextHookEx(k_hookID, nCode, wParam, lParam);
        }

        private IntPtr SetMouseHook(HookHandler proc)
        {
            using (ProcessModule module = Process.GetCurrentProcess().MainModule)
                return SetWindowsHookEx(WH_MOUSE_LL, proc, GetModuleHandle(module.ModuleName), 0);
        }

        private IntPtr SetKeyboardHook(HookHandler proc)
        {
            using (ProcessModule module = Process.GetCurrentProcess().MainModule)
                return SetWindowsHookEx(WH_KEYBOARD_LL, proc, GetModuleHandle(module.ModuleName), 0);
        }
    }


}