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/**
 * @file Safety.cpp
 */

#include "Safety.hpp"
#include <circuit_breaker/circuit_breaker.h>

using namespace time_literals;

Safety::Safety()
{
	// Safety can be turned off with the CBRK_IO_SAFETY parameter.
	_safety_disabled = circuit_breaker_enabled("CBRK_IO_SAFETY", CBRK_IO_SAFETY_KEY);

	if (_safety_disabled) {
		_button_available = true;
		_safety_off = true;
	}
}

bool Safety::safetyButtonHandler()
{
	if (!_safety_disabled) {
		if (!_button_available && _safety_button_sub.advertised()) {
			_button_available = true;
		}

		button_event_s button_event;

		while (_safety_button_sub.update(&button_event)) {
			_safety_off |= button_event.triggered; // triggered safety button activates safety off
		}
	}

	const bool safety_changed = _previous_safety_off != _safety_off;
	_previous_safety_off = _safety_off;
	return safety_changed;
}

void Safety::activateSafety()
{
	if (!_safety_disabled) {
		_safety_off = false;
	}
}