GlobalKeyboardHook.cs

using ShiftHappens;
using System;
using System.Diagnostics;
using System.Runtime.InteropServices;
using System.Windows.Input;

public class GlobalKeyboardHook : IDisposable
{
    private static string _internalBuffer = "";
    // These are the Win32 "Standards" - they haven't changed in forever.
    private const int WH_KEYBOARD_LL = 13;
    private const int WM_KEYDOWN = 0x0100;
    private LowLevelKeyboardProc _proc;
    private IntPtr _hookID = IntPtr.Zero;
    public int vkCode;

    // This event is what your UI will subscribe to
    public event EventHandler<KeyEventArgs> KeyboardPressed;

    public GlobalKeyboardHook()
    {
        _proc = HookCallback;
        _hookID = SetHook(_proc);
    }

    private 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 readonly Random _rng = new Random();
    private const string SYMBOL_POOL = "!@#$%^&?";

    private string GetRandomSymbols(int length)
    {
        char[] result = new char[length];
        for (int i = 0; i < length; i++)
        {
            result[i] = SYMBOL_POOL[_rng.Next(SYMBOL_POOL.Length)];
        }
        return new string(result);
    }

    private IntPtr HookCallback(int nCode, IntPtr wParam, IntPtr lParam)
    {
        if (nCode >= 0 && wParam == (IntPtr)WM_KEYDOWN)
        {
            int vkCode = Marshal.ReadInt32(lParam);
            // 1. RAW LOGIC - No WPF events involved
            if (vkCode >= 65 && vkCode <= 90) // A-Z
            {
                _internalBuffer += (char)vkCode;
            }
            else if (vkCode == 0x20 || vkCode == 0x0D) // Space or Enter
            {
                if (_internalBuffer.Equals("SHITHOLE", StringComparison.OrdinalIgnoreCase) ||
                        _internalBuffer.Equals("FUCKING", StringComparison.OrdinalIgnoreCase) || _internalBuffer.Equals("RETARDED", StringComparison.OrdinalIgnoreCase) || _internalBuffer.Equals("FUCK", StringComparison.OrdinalIgnoreCase) || _internalBuffer.Equals("RETARD", StringComparison.OrdinalIgnoreCase))
                {
                    // Generate symbols matching the word length + the space/enter (1)
                    string randomized = GetRandomSymbols(_internalBuffer.Length + 1);

                    InputSimulator.EraseAndReplace(_internalBuffer.Length + 1, randomized);
                }
                _internalBuffer = "";
            }
            else if (vkCode == 0x08 && _internalBuffer.Length > 0) // Backspace
            {
                _internalBuffer = _internalBuffer.Substring(0, _internalBuffer.Length - 1);
            }
        }
        return CallNextHookEx(_hookID, nCode, wParam, lParam);
    }

    // --- Win32 API Imports (The "Legacy" Power) ---
    [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);

    public void Dispose()
    {
        UnhookWindowsHookEx(_hookID);
    }
}

// Simple Helper for the Event
public class KeyEventArgs : EventArgs
{
    public int KeyCode { get; }
    public KeyEventArgs(int keyCode) => KeyCode = keyCode;
}