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/**
 * @file MulticopterLandDetector.h
 * Land detection algorithm for multicopters
 *
 * @author Johan Jansen <jnsn.johan@gmail.com>
 * @author Morten Lysgaard <morten@lysgaard.no>
 */

#ifndef __MULTICOPTER_LAND_DETECTOR_H__
#define __MULTICOPTER_LAND_DETECTOR_H__

#include "LandDetector.h"
#include <uORB/topics/vehicle_global_position.h>
#include <uORB/topics/vehicle_attitude.h>
#include <uORB/topics/vehicle_status.h>
#include <uORB/topics/actuator_controls.h>
#include <uORB/topics/actuator_armed.h>
#include <uORB/topics/parameter_update.h>
#include <systemlib/param/param.h>

class MulticopterLandDetector : public LandDetector
{
public:
	MulticopterLandDetector();

protected:
	/**
	* @brief  polls all subscriptions and pulls any data that has changed
	**/
	void updateSubscriptions();

	/**
	* @brief Runs one iteration of the land detection algorithm
	**/
	bool update() override;

	/**
	* @brief Initializes the land detection algorithm
	**/
	void initialize() override;


private:
	/**
	* @brief download and update local parameter cache
	**/
	void updateParameterCache(const bool force);

	/**
	* @brief Handles for interesting parameters
	**/
	struct {
		param_t maxClimbRate;
		param_t maxVelocity;
		param_t maxRotation;
		param_t maxThrottle;
	}		_paramHandle;

	struct {
		float maxClimbRate;
		float maxVelocity;
		float maxRotation;
		float maxThrottle;
	} _params;

private:
	int _vehicleGlobalPositionSub;                                      /**< notification of global position */
	int _vehicleStatusSub;
	int _actuatorsSub;
	int _armingSub;
	int _parameterSub;
	int _attitudeSub;

	struct vehicle_global_position_s          _vehicleGlobalPosition;   /**< the result from global position subscription */
	struct vehicle_status_s 			      _vehicleStatus;
	struct actuator_controls_s                _actuators;
	struct actuator_armed_s                   _arming;
	struct vehicle_attitude_s                 _vehicleAttitude;

	uint64_t _landTimer;                                                /**< timestamp in microseconds since a possible land was detected*/
};

#endif //__MULTICOPTER_LAND_DETECTOR_H__