rc_loss_alarm.h

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/**
 * @file rc_loss_alarm.h
 * Tone alarm in the event of RC loss
 *
 */

#pragma once

#include "subscriber_handler.h"

#include <uORB/uORB.h>
#include <uORB/topics/vehicle_status.h>

namespace events
{
namespace rc_loss
{

class RC_Loss_Alarm
{
public:

    RC_Loss_Alarm(const events::SubscriberHandler &subscriber_handler);

    /** regularily called to handle state updates */
    void process();

private:
    /**
     * check for topic updates
     * @return true if one or more topics got updated
     */
    bool check_for_updates();

    /** Publish tune control to sound alarm */
    void play_tune();

    /** Publish tune control to interrupt any sound */
    void stop_tune();

    struct vehicle_status_s _vehicle_status = {};
    bool        _was_armed = false;
    bool        _had_rc = false;  // Don't trigger alarm for systems without RC
    bool        _alarm_playing = false;
    orb_advert_t    _tune_control_pub = nullptr;
    const events::SubscriberHandler &_subscriber_handler;
};

} /* namespace rc_loss */
} /* namespace events */