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/**
 * @file FlightTaskDescend.cpp
 */

#include "FlightTaskDescend.hpp"

bool FlightTaskDescend::activate(vehicle_local_position_setpoint_s last_setpoint)
{
	bool ret = FlightTask::activate(last_setpoint);
	// stay level to minimize horizontal drift
	_thrust_setpoint = matrix::Vector3f(0.0f, 0.0f, NAN);
	// keep heading
	_yaw_setpoint = _yaw;
	return ret;
}

bool FlightTaskDescend::update()
{
	if (PX4_ISFINITE(_velocity(2))) {
		// land with landspeed
		_velocity_setpoint(2) = _param_mpc_land_speed.get();
		_thrust_setpoint(2) = NAN;

	} else {
		// descend with constant thrust (crash landing)
		_velocity_setpoint(2) = NAN;
		_thrust_setpoint(2) = -_param_mpc_thr_hover.get() * 0.7f;
	}

	return true;
}