send_event.h

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#pragma once

#include "subscriber_handler.h"
#include "status_display.h"
#include "rc_loss_alarm.h"

#include <px4_platform_common/workqueue.h>
#include <px4_platform_common/module.h>
#include <px4_platform_common/module_params.h>
#include <uORB/PublicationQueued.hpp>
#include <uORB/topics/vehicle_command.h>
#include <uORB/topics/vehicle_command_ack.h>

namespace events
{

extern "C" __EXPORT int send_event_main(int argc, char *argv[]);

/** @class SendEvent The SendEvent class manages the RC loss audible alarm, LED status display, and thermal calibration. */
class SendEvent : public ModuleBase<SendEvent>, public ModuleParams
{
public:

    SendEvent();

    ~SendEvent();

    /**
     * @see ModuleBase
     * @brief Recognizes custom startup commands, called from the main() function entry.
     * @param argc The task argument count.
     * @param argc Pointer to the task argument variable array.
     * @return Returns 0 iff successful, otherwise < 0 on error.
     */
    static int custom_command(int argc, char *argv[]);

    /**
     * @see ModuleBase
     * @brief Prints usage options to the console.
     * @param reason The requested usage reason for printing to console.
     * @return Returns 0 iff successful, -1 otherwise.
     */
    static int print_usage(const char *reason = nullptr);

    /**
     * @brief Spawns and initializes the class in the same context as the
     *        work queue and starts the background listener.
     * @param argc The input argument count.
     * @param argv Pointer to the input argument array.
     * @return Returns 0 iff successful, -1 otherwise.
     */
    static int task_spawn(int argc, char *argv[]);

private:

    /**
     * @brief Returns an ACK to a vehicle_command.
     * @param cmd The vehicle command struct being referenced.
     * @param result The command acknowledgement result.
     */
    void answer_command(const vehicle_command_s &cmd, unsigned result);

    /**
     * @brief Process cycle trampoline for the work queue.
     * @param arg Pointer to the task startup arguments.
     */
    static void cycle_trampoline(void *arg);

    /**
     * @brief Calls process_commands() and schedules the next cycle.
     */
    void cycle();

    /**
     * @brief Trampoline for initialisation.
     * @param arg Pointer to the task startup arguments.
     */
    static void initialize_trampoline(void *arg);

    /**
     * @brief Checks for new commands and processes them.
     */
    void process_commands();

    /**
     * @brief Starts background task listening for commands.
     * @return Returns 0 iff successful, otherwise < 0 on error.
     */
    int start();

    /** @struct _work The work queue struct. */
    static struct work_s _work;

    /** @var _subscriber_handler The uORB subscriber handler. */
    SubscriberHandler _subscriber_handler;

    /** @var _status_display Pointer to the status display object. */
    status::StatusDisplay *_status_display = nullptr;

    /** @var _rc_loss_alarm Pointer to the RC loss alarm object. */
    rc_loss::RC_Loss_Alarm *_rc_loss_alarm = nullptr;

    /** @note Declare local parameters using defined parameters. */
    DEFINE_PARAMETERS(
        /** @var _param_status_display Parameter to enable/disable the LED status display. */
        (ParamBool<px4::params::EV_TSK_STAT_DIS>) _param_ev_tsk_stat_dis,

        /** @var _param_rc_loss The RC comms loss status flag. */
        (ParamBool<px4::params::EV_TSK_RC_LOSS>) _param_ev_tsk_rc_loss
    )
};

} // namespace events