#include <iostream>
#include <Windows.h>

using namespace std;

/*
 0: ok
-1: error
*/
int addEnvPath(string envKey, string envValue) {
	HKEY hKey;
	const char *key = "Environment";
	DWORD dwType = REG_SZ;
	char data[1024] = {};
	DWORD dwSize = sizeof(data);
	string environment = data;

	if (RegOpenKeyEx(HKEY_CURRENT_USER, key, 0, KEY_READ | KEY_WRITE, &hKey) != ERROR_SUCCESS)
	{
		cout << "RegOpenKeyEx Failure!" << endl;
		return -1;
	}

	if (RegQueryValueEx(hKey, envKey.c_str(), NULL, &dwType, (LPBYTE)data, &dwSize) != ERROR_SUCCESS)
	{
		cout << "RegQueryValueEx Failure!" << endl;
		return -1;
	}

	if (environment.length() == 0)
	{
		environment = envValue;
	}
	else if (environment.find(envValue) != std::string::npos)
	{
		return 0;
	}
	else
	{
		environment += ";" + envValue;
	}

	if (RegSetValueEx(hKey, envKey.c_str(), NULL, REG_SZ, (const unsigned char *)environment.c_str(), strlen(environment.c_str())) != ERROR_SUCCESS)
	{
		cout << "RegSetValueEx Failure!" << endl;
		return -1;
	}
	RegCloseKey(hKey);

	return 0;
}

int main(int argc, char** argv) {
	addEnvPath("Path", "c:\\soft\\");
	addEnvPath("Path", "c:\\soft1\\");
	addEnvPath("Path", "c:\\soft1\\");
	return 0;
}