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/**
 * @file FlightTaskOrbit.hpp
 *
 * Flight task for orbiting in a circle around a target position
 *
 * @author Matthias Grob <maetugr@gmail.com>
 */

#pragma once

#include "FlightTaskManual.hpp"

class FlightTaskOrbit : public FlightTaskManual
{
public:
	FlightTaskOrbit();
	virtual ~FlightTaskOrbit() = default;

	bool applyCommandParameters(const vehicle_command_s &command) override;
	bool activate() override;
	bool update() override;

	/**
	 * Check the feasibility of orbit parameters with respect to
	 * centripetal acceleration a = v^2 / r
	 * @param r desired radius
	 * @param v desired velocity
	 * @param a maximal allowed acceleration
	 * @return true on success, false if value not accepted
	 */
	bool checkAcceleration(float r, float v, float a);

protected:

	/**
	 * Change the radius of the circle.
	 * @param r desired new radius
	 * @return true on success, false if value not accepted
	 */
	bool setRadius(const float r);

	/**
	 * Change the velocity of the vehicle on the circle.
	 * @param v desired new velocity
	 * @return true on success, false if value not accepted
	 */
	bool setVelocity(const float v);

private:
	float _r = 0.f; /**< radius with which to orbit the target */
	float _v = 0.f; /**< linear velocity for orbiting in m/s */
	float _z = 0.f; /**< local z coordinate in meters */
	matrix::Vector2f _center;

	// TODO: create/use parameters for limits
	const float radius_min = 1.f;
	const float radius_max = 20.f;
	const float velocity_max = 10.f;
	const float acceleration_max = 2.f;
};