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/**
 * @file RoverLandDetector.cpp
 * Land detection algorithm for Rovers
 *
 * @author Roman Bapst <bapstroma@gmail.com>
 * @author Julian Oes <julian@oes.ch>
 */

#include "RoverLandDetector.h"

namespace land_detector
{

RoverLandDetector::RoverLandDetector()
{
	_landed_hysteresis.set_hysteresis_time_from(true, 500_ms);
}

bool RoverLandDetector::_get_ground_contact_state()
{
	return true;
}

bool RoverLandDetector::_get_landed_state()
{
	// If Landing has been requested then say we have landed.
	if (_vehicle_status.nav_state == vehicle_status_s::NAVIGATION_STATE_AUTO_LAND
	    || _vehicle_status.nav_state == vehicle_status_s::NAVIGATION_STATE_DESCEND) {
		return true;

	}

	// If we are in RTL and have reached the last valid waypoint then we are landed.
	if (_vehicle_status.nav_state == vehicle_status_s::NAVIGATION_STATE_AUTO_RTL) {
		vehicle_global_position_s vehicle_global_position{};
		_vehicle_global_position_sub.copy(&vehicle_global_position);
		position_setpoint_triplet_s position_setpoint_triplet{};
		_position_setpoint_triplet_sub.copy(&position_setpoint_triplet);

		const float distance_to_curr_wp = get_distance_to_next_waypoint(vehicle_global_position.lat,
						  vehicle_global_position.lon,
						  position_setpoint_triplet.current.lat, position_setpoint_triplet.current.lon);
		return distance_to_curr_wp < _param_nav_acc_rad.get() && !position_setpoint_triplet.next.valid;

	}

	return !_armed;  // If we are armed we are not landed.
}

} // namespace land_detector