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 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
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 *    notice, this list of conditions and the following disclaimer in
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/**
 * @file mavlink_timesync.cpp
 * Mavlink timesync implementation.
 *
 * @author Mohammed Kabir <mhkabir98@gmail.com>
 */

#include "mavlink_timesync.h"
#include "mavlink_main.h"

#include <stdlib.h>

MavlinkTimesync::MavlinkTimesync(Mavlink &mavlink) :
	_mavlink(mavlink)
{
}

void
MavlinkTimesync::handle_message(const mavlink_message_t *msg)
{
	switch (msg->msgid) {
	case MAVLINK_MSG_ID_TIMESYNC: {

			mavlink_timesync_t tsync = {};
			mavlink_msg_timesync_decode(msg, &tsync);

			const uint64_t now = hrt_absolute_time();

			if (tsync.tc1 == 0) {			// Message originating from remote system, timestamp and return it

				mavlink_timesync_t rsync;

				rsync.tc1 = now * 1000ULL;
				rsync.ts1 = tsync.ts1;

				mavlink_msg_timesync_send_struct(_mavlink.get_channel(), &rsync);

				return;

			} else if (tsync.tc1 > 0) {		// Message originating from this system, compute time offset from it

				_timesync.update(now, tsync.tc1, tsync.ts1);
			}

			break;
		}

	case MAVLINK_MSG_ID_SYSTEM_TIME: {

			mavlink_system_time_t time;
			mavlink_msg_system_time_decode(msg, &time);

			timespec tv = {};
			px4_clock_gettime(CLOCK_REALTIME, &tv);

			// date -d @1234567890: Sat Feb 14 02:31:30 MSK 2009
			bool onb_unix_valid = (unsigned long long)tv.tv_sec > PX4_EPOCH_SECS;
			bool ofb_unix_valid = time.time_unix_usec > PX4_EPOCH_SECS * 1000000ULL;

			if (!onb_unix_valid && ofb_unix_valid) {
				tv.tv_sec = time.time_unix_usec / 1000000ULL;
				tv.tv_nsec = (time.time_unix_usec % 1000000ULL) * 1000ULL;

				if (px4_clock_settime(CLOCK_REALTIME, &tv)) {
					PX4_ERR("[timesync] Failed setting realtime clock");
				}
			}

			break;
		}

	default:
		break;
	}
}