//
// Open Service Platform
// Copyright (c) 2012 Samsung Electronics Co., Ltd.
//
// Licensed under the Apache License, Version 2.0 (the License);
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//

/**
 *
 * @file	FLoc_EllipsoidModel.h
 * @brief	This is the header file for the _EllipsoidModel class.
 *
 * This header file contains declaration of the _EllipsoidModel class.
 */

#ifndef _FLOC_INTERNAL_ELLIPSOID_MODEL_H_
#define _FLOC_INTERNAL_ELLIPSOID_MODEL_H_

namespace Tizen { namespace Locations
{

/**
 * @class   _EllipsoidModel
 * @since 2.0

 * This class provides fundamental geodetic constants and operations according to the WGS84 datum.
 *
 * References:
 * @li R.E. Deakin and M.N. Hunter, (2009) 'Geodesics on an ellipsoid - Bessel's method'
 * @li T.Vincenty, 'Direct and inverse solutions of geodesics on the ellipsoid with application of nested equations'
 */
class _EllipsoidModel
{
public:
	static const double SEMI_MAJOR_AXIS;
	static const double SEMI_MINOR_AXIS;
	static const double FLATTENING;
	static const double EARTH_RADIUS;

public:
	/**
	 * Calculates the geodesic distance between the cooridnates P1(lat1, lon1) and P2(lat2, lon2).
	 *
	 * @since 2.0
	 */
	static float GetDistance(double lat1, double lon1, double lat2, double lon2);

	/**
	 * Calculates the forward azimuth of the cooridnates P1(lat1, lon1) and P2(lat2, lon2).
	 *
	 * @since 2.0
	 */
	static float GetAzimuth(double lat1, double lon1, double lat2, double lon2);

private:
	enum ResultType
	{
		RT_DISTANCE,
		RT_FORWARD_AZIMUTH
	};

	_EllipsoidModel(void);
	static float SolveInverseProblem(double lat1, double lon1, double lat2, double lon2, ResultType type);
};  // class _EllipsoidModel

} } // Tizen::Locations

#endif // _FLOC_INTERNAL_ELLIPSOID_MODEL_H_