public class Device {
	private Posix.termios newtio;
	private Posix.termios restoretio;
	public int fd=-1;
	public int byterate;

	public Device(string device, int rate, int bits, int stopbits) {
		Posix.speed_t baudrate = Posix.B9600;

		fd = Posix.open(device, Posix.O_RDWR /*| Posix.O_NONBLOCK*/);

		if(fd < 0) {
			fd = -1;
			stderr.printf("Could not open device!\n");
		}

		Posix.tcflush(fd, Posix.TCIOFLUSH);

		Posix.tcgetattr(fd, out restoretio);

		/* apply settings */
		switch(rate) {
			case 300:
				baudrate = Posix.B300;
				break;
			case 600:
				baudrate = Posix.B600;
				break;
			case 1200:
				baudrate = Posix.B1200;
				break;
			case 2400:
				baudrate = Posix.B2400;
				break;
			case 4800:
				baudrate = Posix.B4800;
				break;
			case 9600:
				baudrate = Posix.B9600;
				break;
			case 19200:
				baudrate = Posix.B19200;
				break;
			case 38400:
				baudrate = Posix.B38400;
				break;
			case 57600:
				baudrate = Posix.B57600;
				break;
			case 115200:
				baudrate = Posix.B115200;
				break;
			case 230400:
				baudrate = Posix.B230400;
				break;
			default:
				/* not supported */
				rate = 9600;
				break;
		}

		Posix.cfsetospeed(ref newtio, baudrate);
		Posix.cfsetispeed(ref newtio, baudrate);

		switch(bits) {
			case 5:
				newtio.c_cflag = (newtio.c_cflag & ~Posix.CSIZE) | Posix.CS5;
				break;
			case 6:
				newtio.c_cflag = (newtio.c_cflag & ~Posix.CSIZE) | Posix.CS6;
				break;
			case 7:
				newtio.c_cflag = (newtio.c_cflag & ~Posix.CSIZE) | Posix.CS7;
				break;
			case 8:
			default:
				newtio.c_cflag = (newtio.c_cflag & ~Posix.CSIZE) | Posix.CS8;
				break;
		}

		newtio.c_cflag |= Posix.CLOCAL | Posix.CREAD;

		newtio.c_cflag &= ~(Posix.PARENB | Posix.PARODD);

		/* TODO: parity */

		newtio.c_cflag &= ~Linux.Termios.CRTSCTS;

		if(stopbits == 2)
			newtio.c_cflag |= Posix.CSTOPB;
		else
			newtio.c_cflag &= ~Posix.CSTOPB;

		newtio.c_iflag = Posix.IGNBRK;

		newtio.c_lflag = 0;
		newtio.c_oflag = 0;

		newtio.c_cc[Posix.VTIME]=1;
		newtio.c_cc[Posix.VMIN]=1;

		newtio.c_lflag &= ~(Posix.ECHONL|Posix.NOFLSH);

		int mcs=0;
		Posix.ioctl(fd, Linux.Termios.TIOCMGET, out mcs);
		mcs |= Linux.Termios.TIOCM_RTS;
		Posix.ioctl(fd, Linux.Termios.TIOCMSET, out mcs);

		Posix.tcsetattr(fd, Posix.TCSANOW, newtio);

		this.byterate = rate/bits;
	}

	private ssize_t read(void *buf, size_t count) {
		return Posix.read(fd, buf, count);
	}

	private ssize_t write(void *buf, size_t count) {
		ssize_t size = Posix.write(fd, buf, count);
		Posix.tcflush(fd, Posix.TCOFLUSH);
		return size;
	}

	public string receive() {
		char[] detected = {};
		char buf[64];

		int size = (int) this.read(buf, 64);

		if(size <= 0)
			error("serial device lost.\n");

		for(int i = 0; i < size; i++) {
			if(buf[i] != '\r' && buf[i] != '\n') {
				detected += (char) buf[i];
			} else {
				if(detected.length > 0) {
					detected += '\0';
					return (string) detected;
				}
			}
		}

		return "";
	}

	/**
	 * @param duration duration of the blink in 0.1 seconds
	 */
	public void blink(uint duration) {
		uint size = byterate/10 * duration;
		var msg = new uint8[size];
		Posix.memset(msg, 0xFF, msg.length);
		this.write(msg, msg.length);
}
}