#define _CRT_SECURE_NO_WARNINGS

#include <Windows.h>
#include <stdio.h>

char id = 1;

HANDLE createPortHandle(const char* port, int baudrate) {
	HANDLE portHandle = CreateFile(port, GENERIC_WRITE | GENERIC_READ, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0);

	if (portHandle == INVALID_HANDLE_VALUE) {
		printf("Cannot open port!\n");
		return INVALID_HANDLE_VALUE;
	}

	DCB params = { 0 };
	params.DCBlength = sizeof(params);
	GetCommState(portHandle, &params);
	params.BaudRate = baudrate;
	params.ByteSize = 8;
	params.StopBits = 0; // 0 == 1
	params.Parity = 0; //StartBit| xxxxxxxx |1or0| StopBit|
	SetCommState(portHandle, &params);

	COMMTIMEOUTS timeouts = { 0 };
	timeouts.ReadIntervalTimeout = 10;
	timeouts.ReadTotalTimeoutConstant = 1;
	timeouts.ReadTotalTimeoutMultiplier = 1;
	timeouts.WriteTotalTimeoutConstant = 50;
	timeouts.WriteTotalTimeoutMultiplier = 50;
	SetCommTimeouts(portHandle, &timeouts);

	return portHandle;
}

static bool terminate = false;

DWORD _stdcall readFunction(void* params) {
	HANDLE portHandle = *(HANDLE*)params;

	char message[256];
	char recvID[2];

	DWORD bytesRead;

	while (!terminate) {
		DWORD flags;
		WaitCommEvent(portHandle, &flags, 0);
		if (flags & EV_CTS) {
			ReadFile(portHandle, recvID, 2, &bytesRead, 0);
			ReadFile(portHandle, message, 256, &bytesRead, 0);
			if (bytesRead > 0) {
				if(id == recvID[0]){
					printf("Recieved message: %s\n", message);
				}
			}
		}
	}
	return 0;
}

int main() {
	char portName[100];
	char recvID[2];

	printf("Enter port: ");
	scanf("%s", portName);

	HANDLE portHandle = createPortHandle(portName, 115200);
	if (portHandle == INVALID_HANDLE_VALUE) {
		return -1;
	}

	DWORD threadID;
	HANDLE threadHandle = CreateThread(NULL, 0, readFunction, &portHandle, 0, &threadID);

	char message[256];
	do {
		printf("Enter reciever ID: ");
		fgets(recvID, 2, stdin);
		recvID[strlen(recvID) - 1] = '\0';
		printf("\n");
		if (strlen(recvID) > 0) {
			DWORD bytesSent;
			EscapeCommFunction(portHandle, SETRTS); //
			WriteFile(portHandle, recvID, strlen(recvID) + 1, &bytesSent, 0);
			EscapeCommFunction(portHandle, CLRRTS); //
			printf("*ID* Number of bytes sent: %ld\n", bytesSent);
		}

		printf("Message: ");
		scanf("%s", &message);
		//fgets(message, 256, stdin);
		message[strlen(message - 1)] = '\0';
		if (strlen(message) > 0) {
			DWORD bytesSent;

			EscapeCommFunction(portHandle, SETRTS); //
			WriteFile(portHandle, message, strlen(message) + 1, &bytesSent, 0);
			EscapeCommFunction(portHandle, CLRRTS); //
			printf("*MSG* Number of bytes sent: %ld\n", bytesSent);
		}
	} while (strcmp(message, "x") != 0);

	terminate = true;
	WaitForSingleObject(threadHandle, INFINITE);
	CloseHandle(threadHandle);

	CloseHandle(portHandle);

	return 0;
}