using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Windows.Forms;
using PTMedicalInsurance.Forms;

namespace PTMedicalInsurance.Business
{
    class KeyBoardHook
    {

        public class KeyboardHook
        {
            private static LowLevelKeyboardProc _proc = HookCallback;
            private static IntPtr _hookID = IntPtr.Zero;

            public static void Start()
            {
                _hookID = SetHook(_proc);
            }

            public static void Stop()
            {
                UnhookWindowsHookEx(_hookID);
            }

            private static IntPtr SetHook(LowLevelKeyboardProc proc)
            {
                using (Process curProcess = Process.GetCurrentProcess())
                using (ProcessModule curModule = curProcess.MainModule)
                {
                    return SetWindowsHookEx(WH_KEYBOARD_LL, proc,
                        GetModuleHandle(curModule.ModuleName), 0);
                }
            }

            private delegate IntPtr LowLevelKeyboardProc(int nCode, IntPtr wParam, IntPtr lParam);

            private static IntPtr HookCallback(int nCode, IntPtr wParam, IntPtr lParam)
            {
                if (nCode >= 0 && wParam == (IntPtr)WM_KEYDOWN)
                {
                    int vkCode = Marshal.ReadInt32(lParam);
                    if (vkCode == (int)Keys.F12) // 使用F12键触发密码键盘
                    {
                        IntPtr foregroundWindow = GetForegroundWindow();
                        StringBuilder windowTitle = new StringBuilder(256);
                        GetWindowText(foregroundWindow, windowTitle, windowTitle.Capacity);

                        // 检测目标程序的窗口
                        if (windowTitle.ToString().Contains("目标程序标题"))
                        {
                            IntPtr focusedHandle = GetFocusedControl();
                            if (focusedHandle != IntPtr.Zero)
                            {
                                ShowPasswordKeyboard(focusedHandle);
                            }
                        }
                    }
                }
                return CallNextHookEx(_hookID, nCode, wParam, lParam);
            }

            private static void ShowPasswordKeyboard(IntPtr targetHandle)
            {
                
                PasswordKeyboardForm passwordKeyboard = new PasswordKeyboardForm(targetHandle);
                passwordKeyboard.ShowDialog();
            }

            private const int WH_KEYBOARD_LL = 13;
            private const int WM_KEYDOWN = 0x0100;

            [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
            private static extern IntPtr SetWindowsHookEx(int idHook, LowLevelKeyboardProc 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);

            [DllImport("user32.dll")]
            private static extern IntPtr GetForegroundWindow();

            [DllImport("user32.dll", CharSet = CharSet.Auto, SetLastError = true)]
            private static extern int GetWindowText(IntPtr hWnd, StringBuilder lpString, int nMaxCount);

            [DllImport("user32.dll")]
            private static extern IntPtr GetFocus();

            [DllImport("user32.dll")]
            private static extern IntPtr GetFocusedControl();
        }
    }
}