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/**
 * @file fw_pitch_controller.cpp
 * Implementation of a simple pitch P controller.
 */

#include "fw_pitch_controller.h"
#include <float.h>
#include <lib/geo/geo.h>
#include <mathlib/mathlib.h>

float PitchController::control_pitch(float pitch_setpoint, float euler_yaw_rate_setpoint, float roll, float pitch)
{
	/* Do not calculate control signal with bad inputs */
	if (!(PX4_ISFINITE(pitch_setpoint) &&
	      PX4_ISFINITE(euler_yaw_rate_setpoint) &&
	      PX4_ISFINITE(pitch) &&
	      PX4_ISFINITE(roll))) {

		return _body_rate_setpoint;
	}

	const float pitch_error = pitch_setpoint - pitch;
	_euler_rate_setpoint = pitch_error / _tc;

	/* Transform setpoint to body angular rates (jacobian) */
	const float pitch_body_rate_setpoint_raw = cosf(roll) * _euler_rate_setpoint +
			cosf(pitch) * sinf(roll) * euler_yaw_rate_setpoint;

	_body_rate_setpoint = math::constrain(pitch_body_rate_setpoint_raw, -_max_rate_neg, _max_rate_pos);

	return _body_rate_setpoint;
}