#include <iostream>
#include <Windows.h>
#include <thread>
#include <atomic>
#include <chrono>
#include <mutex>

std::atomic<bool> isRunning(false);
std::thread simulationThread;
std::mutex simulationMutex;

HWND currentWindowHandle = nullptr;

void simulateSingleKeyPress(WORD key) {
	INPUT input = { 0 };
	input.type = INPUT_KEYBOARD;
	input.ki.wVk = key;

	SendInput(1, &input, sizeof(INPUT));

	input.ki.dwFlags = KEYEVENTF_KEYUP;
	SendInput(1, &input, sizeof(INPUT));
}

void keyPressTimer(WORD key, int delayMilliseconds) {
	while (true) {
		{
			std::lock_guard<std::mutex> lock(simulationMutex);
			if (!isRunning) break;
		}

		if (GetForegroundWindow() == currentWindowHandle) {
			simulateSingleKeyPress(key);
		}

		std::this_thread::sleep_for(std::chrono::milliseconds(delayMilliseconds));
	}
}

void startKeyPressSimulation(WORD key, int delayMilliseconds) {
	std::lock_guard<std::mutex> lock(simulationMutex);

	if (isRunning) {
		std::cout << "Simulation is already running.\n";
		return;
	}

	currentWindowHandle = GetConsoleWindow();
	if (!currentWindowHandle) {
		std::cout << "Failed to get the console window handle.\n";
		return;
	}

	isRunning = true;
	simulationThread = std::thread(keyPressTimer, key, delayMilliseconds);

	if (simulationThread.native_handle()) {
		SetThreadPriority(simulationThread.native_handle(), THREAD_PRIORITY_BELOW_NORMAL);
	}

	std::cout << "Simulation started.\n";
}

void stopKeyPressSimulation() {
	{
		std::lock_guard<std::mutex> lock(simulationMutex);
		if (!isRunning) {
			std::cout << "Simulation is not running.\n";
			return;
		}

		isRunning = false;
	}

	if (simulationThread.joinable()) {
		simulationThread.join();
	}

	std::cout << "Simulation stopped.\n";
}

int main() {
	const WORD key = VK_F11;
	const int delay = 1000;

	std::cout << "Key Press Simulator\n";
	std::cout << "1: Start Simulation\n";
	std::cout << "2: Stop Simulation\n";
	std::cout << "3: Exit\n";

	int choice;
	do {
		std::cout << "\nEnter your choice: ";
		std::cin >> choice;

		switch (choice) {
		case 1:
			startKeyPressSimulation(key, delay);
			break;
		case 2:
			stopKeyPressSimulation();
			break;
		case 3:
			stopKeyPressSimulation();
			std::cout << "Exiting program.\n";
			break;
		default:
			std::cout << "Invalid choice. Try again.\n";
		}
	} while (choice != 3);

	return 0;
}