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/**
 * @file FlightTaskDescend.cpp
 */

#include "FlightTaskDescend.hpp"

bool FlightTaskDescend::activate(const trajectory_setpoint_s &last_setpoint)
{
	bool ret = FlightTask::activate(last_setpoint);
	_gear.landing_gear = landing_gear_s::GEAR_DOWN;
	return ret;
}

bool FlightTaskDescend::update()
{
	bool ret = FlightTask::update();

	if (PX4_ISFINITE(_velocity(2))) {
		// land with landspeed
		_velocity_setpoint(2) = _param_mpc_land_speed.get();
		_acceleration_setpoint(2) = NAN;

	} else {
		// descend with constant acceleration (crash landing)
		_velocity_setpoint(2) = NAN;
		_acceleration_setpoint(2) = .3f;
	}

	// Nudging
	if ((_param_mpc_auto_nudging.get() & 2) && _sticks.checkAndUpdateStickInputs()) {
		_stick_yaw.generateYawSetpoint(_yawspeed_setpoint, _yaw_setpoint, _sticks.getYawExpo(), _yaw, _deltatime);
		_acceleration_setpoint.xy() = _stick_tilt_xy.generateAccelerationSetpoints(_sticks.getPitchRoll(), _deltatime, _yaw,
					      _yaw_setpoint);

		// Stick full up -1 -> stop, stick full down 1 -> double the value
		_velocity_setpoint(2) *= (1 - _sticks.getThrottleZeroCenteredExpo());
		_acceleration_setpoint(2) -= _sticks.getThrottleZeroCentered() * 10.f;

	} else {
		_acceleration_setpoint.xy() = matrix::Vector2f(0.f, 0.f); // stay level to minimize horizontal drift
		_yawspeed_setpoint = NAN;

		// keep heading
		if (!PX4_ISFINITE(_yaw_setpoint)) {
			_yaw_setpoint = _yaw;
		}
	}

	return ret;
}