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/**
 * @file ControlAllocation.cpp
 *
 * Interface for Control Allocation Algorithms
 *
 * @author Julien Lecoeur <julien.lecoeur@gmail.com>
 */

#include "ControlAllocation.hpp"

ControlAllocation::ControlAllocation()
{
	_control_allocation_scale.setAll(1.f);
	_actuator_min.setAll(0.f);
	_actuator_max.setAll(1.f);
}

void
ControlAllocation::setEffectivenessMatrix(
	const matrix::Matrix<float, ControlAllocation::NUM_AXES, ControlAllocation::NUM_ACTUATORS> &effectiveness,
	const ActuatorVector &actuator_trim, const ActuatorVector &linearization_point, int num_actuators,
	bool update_normalization_scale)
{
	_effectiveness = effectiveness;
	ActuatorVector linearization_point_clipped = linearization_point;
	clipActuatorSetpoint(linearization_point_clipped);
	_actuator_trim = actuator_trim + linearization_point_clipped;
	clipActuatorSetpoint(_actuator_trim);
	_num_actuators = num_actuators;
	_control_trim = _effectiveness * linearization_point_clipped;
}

void
ControlAllocation::setActuatorSetpoint(
	const matrix::Vector<float, ControlAllocation::NUM_ACTUATORS> &actuator_sp)
{
	// Set actuator setpoint
	_actuator_sp = actuator_sp;

	// Clip
	clipActuatorSetpoint(_actuator_sp);
}

void
ControlAllocation::clipActuatorSetpoint(matrix::Vector<float, ControlAllocation::NUM_ACTUATORS> &actuator) const
{
	for (int i = 0; i < _num_actuators; i++) {
		if (_actuator_max(i) < _actuator_min(i)) {
			actuator(i) = _actuator_trim(i);

		} else if (actuator(i) < _actuator_min(i)) {
			actuator(i) = _actuator_min(i);

		} else if (actuator(i) > _actuator_max(i)) {
			actuator(i) = _actuator_max(i);
		}
	}
}

matrix::Vector<float, ControlAllocation::NUM_ACTUATORS>
ControlAllocation::normalizeActuatorSetpoint(const matrix::Vector<float, ControlAllocation::NUM_ACTUATORS> &actuator)
const
{
	matrix::Vector<float, ControlAllocation::NUM_ACTUATORS> actuator_normalized;

	for (int i = 0; i < _num_actuators; i++) {
		if (_actuator_min(i) < _actuator_max(i)) {
			actuator_normalized(i) = (actuator(i) - _actuator_min(i)) / (_actuator_max(i) - _actuator_min(i));

		} else {
			actuator_normalized(i) = (_actuator_trim(i) - _actuator_min(i)) / (_actuator_max(i) - _actuator_min(i));
		}
	}

	return actuator_normalized;
}

void ControlAllocation::applySlewRateLimit(float dt)
{
	for (int i = 0; i < _num_actuators; i++) {
		if (_actuator_slew_rate_limit(i) > FLT_EPSILON) {
			float delta_sp_max = dt * (_actuator_max(i) - _actuator_min(i)) / _actuator_slew_rate_limit(i);
			float delta_sp = _actuator_sp(i) - _prev_actuator_sp(i);

			if (delta_sp > delta_sp_max) {
				_actuator_sp(i) = _prev_actuator_sp(i) + delta_sp_max;

			} else if (delta_sp < -delta_sp_max) {
				_actuator_sp(i) = _prev_actuator_sp(i) - delta_sp_max;
			}
		}
	}
}