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/**
 * @file FlightManualAltitude.cpp
 */

#include "FlightTaskManualAltitude.hpp"
#include <float.h>

using namespace matrix;

FlightTaskManualAltitude::FlightTaskManualAltitude(control::SuperBlock *parent, const char *name) :
	FlightTaskManualStabilized(parent, name),
	_vel_max_down(parent, "MPC_Z_VEL_MAX_DN", false),
	_vel_max_up(parent, "MPC_Z_VEL_MAX_UP", false),
	_vel_hold_thr_z(parent, "MPC_HOLD_MAX_Z", false)

{}

bool FlightTaskManualAltitude::activate()
{
	_pos_sp_z = NAN;
	_vel_sp_z = 0.0f;
	return FlightTaskManualStabilized::activate();
}

void FlightTaskManualAltitude::_scaleSticks()
{
	/* Reuse same scaling as for stabilized */
	FlightTaskManualStabilized::_scaleSticks();

	/* Scale horizontal velocity with expo curve stick input*/
	const float vel_max_z = (_sticks(2) > 0.0f) ? _vel_max_down.get() : _vel_max_up.get();
	_vel_sp_z = vel_max_z * _sticks_expo(2);
}

void FlightTaskManualAltitude::_updateAltitudeLock()
{
	/* Depending on stick inputs and velocity, position is locked.
	 * If not locked, altitude setpoint is set to NAN.
	 */

	/* handle position and altitude hold */
	const bool apply_brake_z = fabsf(_vel_sp_z) <= FLT_EPSILON;
	const bool stopped_z = (_vel_hold_thr_z.get() < FLT_EPSILON || fabsf(_velocity(2)) < _vel_hold_thr_z.get());

	if (apply_brake_z && stopped_z && !PX4_ISFINITE(_pos_sp_z)) {
		_pos_sp_z = _position(2);

	} else if (!apply_brake_z) {
		_pos_sp_z = NAN;
	}
}

void FlightTaskManualAltitude::_updateSetpoints()
{
	FlightTaskManualStabilized::_updateSetpoints(); // get yaw setpoint
	/* Thrust in xy are extracted directly from stick inputs. A magnitude of
	 * 1 means that maximum thrust along xy is required. A magnitude of 0 means no
	 * thrust along xy is required. The maximum thrust along xy depends on the thrust
	 * setpoint along z-direction, which is computed in PositionControl.cpp.
	 */
	matrix::Vector3f sp{_sticks(0), _sticks(1), 0.0f};
	sp = (matrix::Dcmf(matrix::Eulerf(0.0f, 0.0f, _yaw)) * sp);

	if (sp.length() > 1.0f) {
		sp.normalize();
	}

	_thr_sp(0) = sp(0);
	_thr_sp(1) = sp(1);

	_updateAltitudeLock(); // get z setpoints
}

bool FlightTaskManualAltitude::update()
{
	_scaleSticks();
	_updateSetpoints();

	_setPositionSetpoint(Vector3f(NAN, NAN, _pos_sp_z));
	_setVelocitySetpoint(Vector3f(NAN, NAN, _vel_sp_z));
	_setYawSetpoint(_yaw_sp);
	_setYawspeedSetpoint(_yaw_rate_sp);
	_setThrustSetpoint(Vector3f(_thr_sp(0), _thr_sp(1), NAN));

	return true;
}