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/**
 * @file SmoothingZ.hpp
 *
 * This Class is used for smoothing the velocity setpoints in Z-direction.
 * In manual altitude control apply acceleration limit based on stick input.
 */

#pragma once

#include <px4_module_params.h>

/**
 * User-intention.
 * - brake: vehicle should stop
 * - acceleration: vehicle should move up or down
 */
enum class ManualIntentionZ {
	brake,
	acceleration,
};

class ManualSmoothingZ : public ModuleParams
{
public:
	ManualSmoothingZ(ModuleParams *parent, const float &vel, const float &stick);
	~ManualSmoothingZ() = default;

	/**
	 * Smooth velocity setpoint based on flight direction.
	 * @param vel_sp[2] array: vel_sp[0] = current velocity set-point;
	 * 					 	   vel_sp[1] = previous velocity set-point
	 * 		  vel_sp will contain smoothed current / previous set-point.
	 * @param dt: time delta in seconds
	 */
	void smoothVelFromSticks(float &vel_sp, const float dt);

	/**
	 * Get max accleration.
	 */
	float getMaxAcceleration() { return _max_acceleration; }

	/**
	 * Get user intention.
	 * @see ManualIntentionZ
	 */
	ManualIntentionZ getIntention() { return _intention; }

	/*
	 * Overwrite methods:
	 * Needed if different parameter values than default required.
	 */
	void overwriteAccelerationUp(float acc_max_up) { _acc_max_up.set(acc_max_up); }
	void overwriteAccelerationDown(float acc_max_down)  {_acc_max_down.set(acc_max_down); }
	void overwriteJerkMax(float jerk_max)  {_jerk_max.set(jerk_max); }

private:
	/**
	 * Add delay to velocity setpoint change.
	 * This method is used to smooth the velocity setpoint change.
	 * @param vel_sp current velocity setpoint
	 * @param dt delta-time
	 */
	void velocitySlewRate(float &vel_sp, const float dt);

	/**
	 * Computes the velocity setpoint change limit.
	 * This method computes the limit with which the velocity setpoint change
	 * is limited.
	 * @see velocitySlewRate
	 * @param vel_sp current velocity setpoint
	 * @param dt delta-time
	 */
	void updateAcceleration(float &vel_sp, const float dt);

	/**
	 * Set maximum acceleration.
	 * The maximum acceleration depends on the desired direction (up vs down).
	 * @see _max_acceleration
	 */
	void setMaxAcceleration();

	/**
	 * User intention
	 * @see ManualIntentionZ
	 */
	ManualIntentionZ _intention{ManualIntentionZ::acceleration};

	const float &_vel; /**< vehicle velocity (dependency injection) */
	const float &_stick; /**< stick input (dependency injection) */

	float _acc_state_dependent; /**< acceleration that depends on _intention */
	float _max_acceleration; /**< can be up or down maximum acceleration */
	float _vel_sp_prev; /**< previous velocity setpoint */

	DEFINE_PARAMETERS(
		(ParamFloat<px4::params::MPC_ACC_UP_MAX>) _acc_max_up,
		(ParamFloat<px4::params::MPC_ACC_DOWN_MAX>) _acc_max_down,
		(ParamFloat<px4::params::MPC_JERK_MAX>) _jerk_max
	)
};