using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Management;
using System.Runtime.InteropServices;
using System.Security.Cryptography;
using System.Text;
using System.Threading.Tasks;

namespace godtier_patcher
{
    public class Patcherino
    {
        public const long FunctionRVA = 0x4A49;
        public readonly byte[] Shellcode = { 0x90, 0x90, 0x90, 0x90, 0x90 };

        public Process Process;
        public IntPtr ProcessHandle;

        [DllImport("kernel32.dll")]
        private static extern bool WriteProcessMemory(IntPtr hProcess, IntPtr lpBaseAddress, byte[] lpBuffer, uint nSize, uint lpNumberOfBytesWritten);

        public Patcherino(Process proc)
        {
            Process = proc;
            this.ProcessHandle = proc.Handle;
            if (this.ProcessHandle == IntPtr.Zero)
                throw new Exception("OpenProcess failed");
        }

        public bool WriteByteArray(long addr, byte[] buffer)
        {
            return WriteProcessMemory(ProcessHandle, (IntPtr)addr, buffer, (uint)buffer.Length, 0);
        }

        public async Task<bool> Patch()
        {
            Log.Info("Module Base Address -> 0x" + Process.MainModule.BaseAddress.ToString("X8"));
            var functionAddress = (long)Process.MainModule.BaseAddress + FunctionRVA;
            Log.Info("Instruction Address (RVA 0x4A49) -> 0x" + functionAddress.ToString("X8") + "\n");
            Log.Critical("Patching...");

            var success = WriteByteArray(functionAddress, Shellcode);

            if (success)
            {
                Log.Critical("Function patched successfully! Thanks for using! Press enter to close this!");
            }
            else
            {
                Log.Error("Could not patch function.");
            }

            return success;
        }
    }
}