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

/*

 * Copyright (c) 2006,2007 INRIA

 *

 * 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 RANDOM_WALK_2D_MOBILITY_MODEL_H

#define RANDOM_WALK_2D_MOBILITY_MODEL_H

#include "ns3/object.h"

#include "ns3/nstime.h"

#include "ns3/event-id.h"

#include "ns3/rectangle.h"

#include "ns3/random-variable.h"

#include "mobility-model.h"

#include "static-speed-helper.h"

namespace ns3 {

/**

 * \brief a 2D random walk position model

 *

 * Each instance moves with a speed and direction choosen at random

 * with the user-provided random variables until

 * either a fixed distance has been walked or until a fixed amount

 * of time. If we hit one of the boundaries (specified by a rectangle),

 * of the model, we rebound on the boundary with a reflexive angle

 * and speed. This model is often identified as a brownian motion

 * model.

 */

class RandomWalk2dMobilityModel : public MobilityModel 

{

 public:

  static TypeId GetTypeId (void);

  enum Mode  {

    MODE_DISTANCE,

    MODE_TIME

  };

  RandomWalk2dMobilityModel ();

 private:

  void Start (void);

  void Rebound (Time timeLeft);

  void DoWalk (Time timeLeft);

  virtual void DoDispose (void);

  virtual Vector DoGetPosition (void) const;

  virtual void DoSetPosition (const Vector &position);

  virtual Vector DoGetVelocity (void) const;

  StaticSpeedHelper m_helper;

  EventId m_event;

  enum Mode m_mode;

  double m_modeDistance;

  Time m_modeTime;

  RandomVariable m_speed;

  RandomVariable m_direction;

  Rectangle m_bounds;

};

} // namespace ns3

#endif /* RANDOM_WALK_2D_MOBILITY_MODEL_H */