/* -*-  Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */

/*

 * Copyright (c) 2006,2007 INRIA

 * All rights reserved.

 *

 * This program is free software; you can redistribute it and/or modify

 * it under the terms of the GNU General Public License version 2 as

 * published by the Free Software Foundation;

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 *

 * Author: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>

 */

#ifndef POSITION_H

#define POSITION_H

#include "ns3/object.h"

namespace ns3 {

/**

 * \brief keep track of the current position of an object

 *

 * All space coordinates in this class and its subclasses are

 * understood to be meters or meters/s. i.e., they are all

 * metric international units.

 */

class MobilityModel : public Object

{

public:

  static const InterfaceId iid;

  MobilityModel ();

  virtual ~MobilityModel () = 0;

  /**

   * \param x reference to floating-point variable for x coordinate.

   * \param y reference to floating-point variable for y coordinate.

   * \param z reference to floating-point variable for z coordinate.

   *

   * Store in the x, y, and z variables the current coordinates

   * managed by this position object.

   * Unit is meters

   */

  void Get (double &x, double &y, double &z) const;

  /**

   * \returns the current x coordinate

   *

   * Unit is meters

   */

  double GetX (void) const;

  /**

   * \returns the current y coordinate

   *

   * Unit is meters

   */

  double GetY (void) const;

  /**

   * \returns the current z coordinate

   *

   * Unit is meters

   */

  double GetZ (void) const;

  void Add (double dx, double dy, double dz);

  void Set (double x, double y, double z);

  void SetXY (double x, double y);

  void SetX (double x);

  void SetY (double y);

  void SetZ (double z);

  /**

   * \param position a reference to another position object instance

   * \returns the distance between the two objects.

   *

   * Unit is meters

   */

  double GetDistanceFrom (const MobilityModel &position) const;

protected:

  /**

   * Must be invoked by subclasses when the course of the

   * position changes to notify course change listeners.

   */

  void NotifyCourseChange (void) const;

private:

  /**

   * \param x reference to floating-point variable for x coordinate.

   * \param y reference to floating-point variable for y coordinate.

   * \param z reference to floating-point variable for z coordinate.

   *

   * Store in the x, y, and z variables the current coordinates

   * managed by this position object. Concrete subclasses of this 

   * base class must implement this method.

   * Unit is meters

   */

  virtual void DoGet (double &x, double &y, double &z) const = 0;

  virtual void DoSet (double x, double y, double z) = 0;

};

}; // namespace ns3

#endif /* POSITION_H */