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/**
 * @file StickYaw.cpp
 */

#include "StickYaw.hpp"

#include <px4_platform_common/defines.h>

StickYaw::StickYaw()
{
	_yawspeed_slew_rate.setSlewRate(2.f * M_PI_F);
}

void StickYaw::generateYawSetpoint(float &yawspeed_setpoint, float &yaw_setpoint, const float desired_yawspeed,
				   const float yaw, const bool is_yaw_good_for_control, const float deltatime)
{
	yawspeed_setpoint = _yawspeed_slew_rate.update(desired_yawspeed, deltatime);
	yaw_setpoint = updateYawLock(yaw, yawspeed_setpoint, yaw_setpoint, is_yaw_good_for_control);
}

float StickYaw::updateYawLock(const float yaw, const float yawspeed_setpoint, const float yaw_setpoint,
			      const bool is_yaw_good_for_control)
{
	// Yaw-lock depends on desired yawspeed input. If not locked, yaw_sp is set to NAN.
	if ((fabsf(yawspeed_setpoint) > FLT_EPSILON) || !is_yaw_good_for_control) {
		// no fixed heading when rotating around yaw by stick
		return NAN;

	} else {
		// break down and hold the current heading when no more rotation commanded
		if (!PX4_ISFINITE(yaw_setpoint)) {
			return yaw;

		} else {
			return yaw_setpoint;
		}
	}
}