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/**
 * @file FlightTaskManualPosition.cpp
 */

#include "FlightTaskManualPosition.hpp"
#include <mathlib/mathlib.h>
#include <float.h>

using namespace matrix;

bool FlightTaskManualPosition::activate()
{

	bool ret = FlightTaskManualAltitude::activate();

	// set task specific constraint
	if (_constraints.speed_xy >= MPC_VEL_MANUAL.get()) {
		_constraints.speed_xy = MPC_VEL_MANUAL.get();
	}

	_velocity_scale = _constraints.speed_xy;

	return ret;
}

void FlightTaskManualPosition::_scaleSticks()
{
	/* Use same scaling as for FlightTaskManualAltitude */
	FlightTaskManualAltitude::_scaleSticks();

	/* Constrain length of stick inputs to 1 for xy*/
	Vector2f stick_xy(_sticks_expo(0), _sticks_expo(1));

	float mag = math::constrain(stick_xy.length(), 0.0f, 1.0f);

	if (mag > FLT_EPSILON) {
		stick_xy = stick_xy.normalized() * mag;
	}

	// scale the stick inputs
	if (_sub_vehicle_local_position->get().vxy_max > 0.001f) {
		// estimator provides vehicle specific max

		// use the minimum of the estimator and user specified limit
		_velocity_scale = fminf(_constraints.speed_xy, _sub_vehicle_local_position->get().vxy_max);
		// Allow for a minimum of 0.3 m/s for repositioning
		_velocity_scale = fmaxf(_velocity_scale, 0.3f);

	} else if (stick_xy.length() > 0.5f) {
		// raise the limit at a constant rate up to the user specified value

		if (_velocity_scale < _constraints.speed_xy) {
			_velocity_scale += _deltatime * MPC_ACC_HOR_FLOW.get();

		} else {
			_velocity_scale = _constraints.speed_xy;

		}
	}

	// scale velocity to its maximum limits
	Vector2f vel_sp_xy = stick_xy * _velocity_scale;

	/* Rotate setpoint into local frame. */
	_rotateIntoHeadingFrame(vel_sp_xy);
	_velocity_setpoint(0) = vel_sp_xy(0);
	_velocity_setpoint(1) = vel_sp_xy(1);
}

void FlightTaskManualPosition::_updateXYlock()
{
	/* If position lock is not active, position setpoint is set to NAN.*/
	const float vel_xy_norm = Vector2f(&_velocity(0)).length();
	const bool apply_brake = Vector2f(&_velocity_setpoint(0)).length() < FLT_EPSILON;
	const bool stopped = (MPC_HOLD_MAX_XY.get() < FLT_EPSILON || vel_xy_norm < MPC_HOLD_MAX_XY.get());

	if (apply_brake && stopped && !PX4_ISFINITE(_position_setpoint(0))) {
		_position_setpoint(0) = _position(0);
		_position_setpoint(1) = _position(1);

	} else if (!apply_brake) {
		/* don't lock*/
		_position_setpoint(0) = NAN;
		_position_setpoint(1) = NAN;
	}
}

void FlightTaskManualPosition::_updateSetpoints()
{
	FlightTaskManualAltitude::_updateSetpoints(); // needed to get yaw and setpoints in z-direction
	_thrust_setpoint *= NAN; // don't require any thrust setpoints
	_updateXYlock(); // check for position lock
}