#include "serial.h"

// port - quel port utiliser (1-4)
Serial::Serial(int port) {
	COM[0] = 'C'; COM[1] = 'O'; COM[2] = 'M'; COM[3] = '0'+port; COM[4] = 0;
	intbuf = new char[1025];
	memset(intbuf, 0, 1025);
}

Serial::~Serial() {
	CloseHandle(hCOM);
	delete intbuf;
}

// Serial::Setup - opens and initializes the COM port to specified settings
// returns false if something went wrong; use GetLastError() to find out specifics
// baud - the baud rate to use; default is 9600
// bits - number of bits/byte; default is 8
// parity - whether or not to use parity; default is NOPARITY  (look up "DCB" in the help file for constants)
// stopbits - number of stopbits; default is ONESTOPBIT (look up "DCB" in the help file for constants)
// flowcontrol - one of HARDWARE (using RTS/CTS), XONXOFF, or NOFLOW; default is HARDWARE
// inbuf/outbuf - input and output buffer sizes; default is 128
bool Serial::Setup(int baud, int bits, int parity, int stopbits, int flowcontrol, int inbuf, int outbuf) {
	DCB dcb;  
	if( (hCOM = CreateFile( COM, GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, NULL))==INVALID_HANDLE_VALUE) return false;
	if( !SetupComm(hCOM, inbuf, outbuf) ) return false;
	if( !GetCommState(hCOM, &dcb) ) return false;
	dcb.BaudRate = baud;
	dcb.ByteSize = bits;
	dcb.fParity = parity;
	dcb.StopBits = stopbits;
	switch( flowcontrol ) {
		case HARDWARE: 
			dcb.fRtsControl = RTS_CONTROL_ENABLE;
			dcb.fInX = false;
			dcb.fOutX = false;
			break;
		case XONXOFF:
			dcb.fRtsControl = RTS_CONTROL_DISABLE;
			dcb.fInX = true;
			dcb.fOutX = true;
			break;
		case NOFLOW:
			dcb.fRtsControl = RTS_CONTROL_DISABLE;
			dcb.fInX = false;
			dcb.fOutX = false;
			break;
	}
	if( !SetCommState(hCOM, &dcb) ) return false;
	return true;
}

bool Serial::WriteBuffer(char *buf, int size) {
	DWORD res;
	if( !WriteFile(hCOM, buf, size, &res, NULL) ) return false;
	if( res != size ) return false;
	return true;
}

// reads a buffer from COM port until a specified character is found
// guarantees that last character is the character specified in cr (or buffer is filled), and stores anything read after that
// basically, therefore, this function returns one line of text read from the serial port
// input size is max size of buffer, output of size is total bytes read
// maximum buffer size is 1024.  sorry.
bool Serial::WaitForChar(char *buf, int &size, char cr) {
	bool err = false;
	bool done = false;
	char *end;
	DWORD res;
	int ofs = 0, len, bytes;
	memset(buf, 0, size);
	if( size > 1024 ) size = 1024;
	if( end=strchr(intbuf, cr) ) {
		len = (unsigned long)end - (unsigned long)intbuf + 1;
		bytes = len >= size ? size : len;
		memmove(buf, intbuf, bytes);
		memmove(intbuf, &intbuf[bytes], 1025 - bytes);
//		memset(&intbuf[bytes], 0, 1025-bytes);
		size = bytes;
		return true;
	} else {
		strncpy(buf, intbuf, size);
		ofs = strlen(buf);
	}
	do {
		if( !ReadFile(hCOM, &buf[ofs], size-ofs, &res, NULL) ) {
			done = true; 
			err = true;
		} else {
			if( end=strchr(&buf[ofs], cr) ) {
				done = true;
				strncpy(intbuf, end+1, 1024);
				end[1] = 0;
			} else ofs += res;
		}
	} while( !done || ofs==size );
	if( err ) return false; else return true;
}