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 *   Copyright (c) 2016 PX4 Development Team. All rights reserved.
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 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name PX4 nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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/**
 * @file hysteresis.cpp
 *
 * @author Julian Oes <julian@oes.ch>
 */

#include <px4_log.h>
#include "systemlib/hysteresis/hysteresis.h"


namespace systemlib
{


void
Hysteresis::set_state_and_update(const bool new_state)
{
	if (new_state != _state) {
		if (new_state != _requested_state) {
			_requested_state = new_state;
			_last_time_to_change_state = hrt_absolute_time();
		}

	} else {
		_requested_state = _state;
	}

	update();
}

void
Hysteresis::update()
{
	if (_requested_state != _state) {

		if (hrt_elapsed_time(&_last_time_to_change_state) >= (_state ?
				_hysteresis_time_from_true_us :
				_hysteresis_time_from_false_us)) {
			_state = _requested_state;
		}
	}
}

} // namespace systemlib
