#include "serial_io.h"

ssize_t sWrite(int port, char string[], size_t length)
{
	if(port != -1)
		return write(port, string, length);
	else
		return 0;
}

ssize_t sWrite(int port, const char string[], size_t length)
{
	if(port != -1)
		return write(port, string, length);
	else
		return 0;
}

ssize_t sRead(int port, void *buf, size_t count)
{
	return (port != -1) ? read(port, buf, count) : 0;
}

#ifdef __cplusplus
void printRates()
{
	std::cout<<"Rates:\n"\
	         <<"Unchanged 0\n"        \
	         <<"B50       "<<B50<<'\n'\
	         <<"B75       "<<B75<<'\n'\
	         <<"B110      "<<B110<<'\n'\
	         <<"B134      "<<B134<<'\n'\
	         <<"B150      "<<B150<<'\n'\
	         <<"B200      "<<B200<<'\n'\
	         <<"B300      "<<B300<<'\n'\
	         <<"B600      "<<B600<<'\n'\
	         <<"B1200     "<<B1200<<'\n'\
	         <<"B1800     "<<B1800<<'\n'\
	         <<"B2400     "<<B2400<<'\n'\
	         <<"B4800     "<<B4800<<'\n'\
	         <<"B9600     "<<B9600<<'\n'\
	         <<"B19200    "<<B19200<<'\n'\
	         <<"B38400    "<<B38400<<'\n'\
	         <<"B57600    "<<B57600<<'\n'\
	         <<"B115200   "<<B115200<<'\n'\
	         <<"B230400   "<<B230400<<'\n';
}
#endif

int serialport_set_config(int fd, int baud)
{
	struct termios toptions;
	if (tcgetattr(fd, &toptions) < 0)
	{
		perror("init_serialport: Couldn't get term attributes");
		return -1;
	}
	// 8N1
	toptions.c_cflag &= ~PARENB;
	toptions.c_cflag &= ~CSTOPB;
	toptions.c_cflag &= ~CSIZE;
	toptions.c_cflag |= CS8;

	// no flow control
	toptions.c_cflag &= ~(CRTSCTS | CLOCAL);

	//Make Raw
	toptions.c_iflag &= ~(IGNBRK | BRKINT | PARMRK | ISTRIP | INLCR | IGNCR | ICRNL | IXON);
	toptions.c_oflag &= ~OPOST; //hmm examine
	toptions.c_lflag &= ~(ECHO | ECHONL | ICANON | ISIG | IEXTEN);
	toptions.c_cflag &= ~(CSIZE | PARENB);
	toptions.c_cflag |= CS8;

	if(baud != 0)
	{
		int error = cfsetispeed(&toptions, baud) | cfsetospeed(&toptions, baud);

		if(error)
		{
			perror("init_serialport: Couldn't set baud rate");
			return -1;
		}
	}
	// see: http://unixwiz.net/techtips/termios-vmin-vtime.html
	toptions.c_cc[VMIN]  = 0;
	toptions.c_cc[VTIME] = 40;
	fcntl(fd, F_SETFL, FNDELAY);
	if( tcsetattr(fd, TCSANOW, &toptions) < 0)
	{
		perror("init_serialport: Couldn't set term attributes");
		return -1;
	}
	return 0;
}

int serialport_init(const char* device, int baud, bool block)
{
	int fd;
	fd = open(device, O_RDWR | O_NOCTTY | (block ? 0 : O_NONBLOCK));
	if (fd == -1)
	{
		perror("init_serialport: Unable to open port ");
		return -1;
	}

	if(serialport_set_config(fd, baud) != 0)
	{
		close(fd);
		fd = -1;
	}
	return fd;
}