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 *    used to endorse or promote products derived from this software
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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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#include <termios.h>
#include <errno.h>
#include <systemlib/err.h>
#include <drivers/drv_hrt.h>
#include "gps_helper.h"

/**
 * @file gps_helper.cpp
 *
 * @author Thomas Gubler <thomasgubler@student.ethz.ch>
 * @author Julian Oes <joes@student.ethz.ch>
 */

float
GPS_Helper::get_position_update_rate()
{
	return _rate_lat_lon;
}

float
GPS_Helper::get_velocity_update_rate()
{
	return _rate_vel;
}

void
GPS_Helper::reset_update_rates()
{
	_rate_count_vel = 0;
	_rate_count_lat_lon = 0;
	_interval_rate_start = hrt_absolute_time();
}

void
GPS_Helper::store_update_rates()
{
	_rate_vel = _rate_count_vel / (((float)(hrt_absolute_time() - _interval_rate_start)) / 1000000.0f);
	_rate_lat_lon = _rate_count_lat_lon / (((float)(hrt_absolute_time() - _interval_rate_start)) / 1000000.0f);
}

int
GPS_Helper::set_baudrate(const int &fd, unsigned baud)
{
	/* process baud rate */
	int speed;

	switch (baud) {
	case 9600:   speed = B9600;   break;

	case 19200:  speed = B19200;  break;

	case 38400:  speed = B38400;  break;

	case 57600:  speed = B57600;  break;

	case 115200: speed = B115200; break;

	default:
		warnx("ERR: baudrate: %d\n", baud);
		return -EINVAL;
	}

	struct termios uart_config;

	int termios_state;

	/* fill the struct for the new configuration */
	tcgetattr(fd, &uart_config);

	/* clear ONLCR flag (which appends a CR for every LF) */
	uart_config.c_oflag &= ~ONLCR;
	/* no parity, one stop bit */
	uart_config.c_cflag &= ~(CSTOPB | PARENB);

	/* set baud rate */
	if ((termios_state = cfsetispeed(&uart_config, speed)) < 0) {
		warnx("ERR: %d (cfsetispeed)\n", termios_state);
		return -1;
	}

	if ((termios_state = cfsetospeed(&uart_config, speed)) < 0) {
		warnx("ERR: %d (cfsetospeed)\n", termios_state);
		return -1;
	}

	if ((termios_state = tcsetattr(fd, TCSANOW, &uart_config)) < 0) {
		warnx("ERR: %d (tcsetattr)\n", termios_state);
		return -1;
	}

	return 0;
}