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

/*

 * Copyright (c) 2006 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 SUPPORTED_RATES_H

#define SUPPORTED_RATES_H

#include <stdint.h>

#include <ostream>

#include "ns3/buffer.h"

#include "ns3/wifi-information-element.h"

namespace ns3 {

/**

 * This defines the maximum number of supported rates that a STA is

 * allowed to have. Currently this number is set for IEEE 802.11b/g

 * stations which need 2 rates each from Clauses 15 and 18, and then 8

 * from Clause 19.

 */

#define MAX_SUPPORTED_RATES (12)

class SupportedRates;

/**

 * \brief The Extended Supported Rates Information Element

 *

 * This class knows how to serialise and deserialise the Extended

 * Supported Rates Element that holds (non-HT) rates beyond the 8 that

 * the original Supported Rates element can carry.

 *

 * The \c SupportedRates class still records all the rates, and an

 * instance of \c ExtendedSupportedRatesIE lies within \c

 * SupportedRates.

 */

class ExtendedSupportedRatesIE : public WifiInformationElement {

public:

  ExtendedSupportedRatesIE ();

  ExtendedSupportedRatesIE (SupportedRates *rates);

  WifiInformationElementId ElementId () const;

  uint8_t GetInformationFieldSize () const;

  void SerializeInformationField (Buffer::Iterator start) const;

  uint8_t DeserializeInformationField (Buffer::Iterator start,

                                       uint8_t length);

  /*

   * This information element is a bit special in that it is only

   * included if there are more than 8 rates. To support this we

   * override the Serialize and GetSerializedSize methods of

   * WifiInformationElement.

   */

  Buffer::Iterator Serialize (Buffer::Iterator start) const;

  uint16_t GetSerializedSize () const;

private:

  /**

   * This member points to the SupportedRates object that contains the

   * actual rate details. This class is a friend of that, so we have

   * access to all the private data we need.

   */

  SupportedRates *m_supportedRates;

};

/**

 * \brief The Supported Rates Information Element

 *

 * This class knows how to serialise and deserialise the Supported

 * Rates Element that holds the first 8 (non-HT) supported rates.

 *

 * The \c ExtendedSupportedRatesIE class (of which an instance exists

 * in objects of this class) deals with rates beyond the first 8.

 */

class SupportedRates : public WifiInformationElement {

public:

  SupportedRates ();

  void AddSupportedRate (uint32_t bs);

  void SetBasicRate (uint32_t bs);

  bool IsSupportedRate (uint32_t bs) const;

  bool IsBasicRate (uint32_t bs) const;

  uint8_t GetNRates (void) const;

  uint32_t GetRate (uint8_t i) const;

  WifiInformationElementId ElementId () const;

  uint8_t GetInformationFieldSize () const;

  void SerializeInformationField (Buffer::Iterator start) const;

  uint8_t DeserializeInformationField (Buffer::Iterator start,

                                  uint8_t length);

  /*

   * We support the Extended Supported Rates Information Element

   * through the ExtendedSupportedRatesIE object which is declared

   * above. We allow this class to be a friend so that it can access

   * our private data detailing the rates, and create an instance as

   * extended.

   */

  friend class ExtendedSupportedRatesIE;

  ExtendedSupportedRatesIE extended;

private:

  uint8_t m_nRates;

  uint8_t m_rates[MAX_SUPPORTED_RATES];

};

std::ostream &operator << (std::ostream &os, const SupportedRates &rates);

} // namespace ns3

#endif /* SUPPORTED_RATES_H */