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

/*

 * Copyright (c) 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_STREAM_H

#define RANDOM_STREAM_H

#include <stdint.h>

#include <list>

#include "ns3/random-variable-stream.h"

namespace ns3 {

/**

 * A simple wrapper around RngStream to make testing

 * of the code easier.

 */

class RandomStream

{

public:

  virtual ~RandomStream ();

  /**

   * Get integer between min and max (including min and max).

   *

   * \param min lower bound (inclusive)

   * \param max upper bound (inclusive)

   * \return a random number between min and max (including min and max)

   */

  virtual uint32_t GetNext (uint32_t min, uint32_t max) = 0;

 /**

  * Assign a fixed random variable stream number to the random variables

  * used by this model.  Return the number of streams (possibly zero) that

  * have been assigned.

  *

  * \param stream first stream index to use

  * \return the number of stream indices assigned by this model

  */

  virtual int64_t AssignStreams (int64_t stream) = 0;

};

class RealRandomStream : public RandomStream

{

public:

  RealRandomStream ();

  virtual uint32_t GetNext (uint32_t min, uint32_t max);

 /**

  * Assign a fixed random variable stream number to the random variables

  * used by this model.  Return the number of streams (possibly zero) that

  * have been assigned.

  *

  * \param stream first stream index to use

  * \return the number of stream indices assigned by this model

  */

  virtual int64_t AssignStreams (int64_t stream);

private:

  /// Provides uniform random variables.

  Ptr<UniformRandomVariable> m_stream;

};

class TestRandomStream : public RandomStream

{

public:

  /**

   * Add the given value to the list.

   *

   * \param v

   */

  void AddNext (uint32_t v);

  virtual uint32_t GetNext (uint32_t min, uint32_t max);

 /**

  * Assign a fixed random variable stream number to the random variables

  * used by this model.  Return the number of streams (possibly zero) that

  * have been assigned.

  *

  * \param stream first stream index to use

  * \return the number of stream indices assigned by this model

  */

  virtual int64_t AssignStreams (int64_t stream);

private:

  std::list<uint32_t> m_nexts;

};

} // namespace ns3

#endif /* RANDOM_STREAM_H */