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

/*

 * Copyright (c) 2007 Emmanuelle Laprise

 * 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: Emmanuelle Laprise <emmanuelle.laprise@bluekazoo.ca>

 */

#ifndef ETHERNET_HEADER_H

#define ETHERNET_HEADER_H

#include "ns3/header.h"

#include <string>

namespace ns3 {

  /**

   * Types of ethernet packets. Indicates the type of the current

   * header.

   */

  enum ethernet_header_t {

    LENGTH,   /**< Basic ethernet packet, no tags, type/length field

                 indicates packet length or IP/ARP packet */

    VLAN,     /**< Single tagged packet. Header includes VLAN tag */

    QINQ      /**< Double tagged packet. Header includes two VLAN tags */

  };

/**

 * \brief Packet header for Ethernet

 *

 * This class can be used to add a header to an ethernet packet that

 * will specify the source and destination addresses and the length of

 * the packet. Eventually the class will be improved to also support

 * VLAN tags in packet headers.

 */

class EthernetHeader : public Header 

{

public:

  static uint32_t GetUid (void);

  /**

   * \brief Construct a null ethernet header

   * \param hasPreamble if true, insert and remove an ethernet preamble from the

   *       packet, if false, does not insert and remove it.

   */

  EthernetHeader (bool hasPreamble);

  /**

   * \brief Construct a null ethernet header

   * By default, does not add or remove an ethernet preamble

   */

  EthernetHeader ();

  /**

   * \param size The size of the payload in bytes

   */

  void SetLengthType (uint16_t size);

  /**

   * \param source The source address of this packet

   */

  /**

   * \param destination The destination address of this packet.

   */

  /**

   * \param preambleSfd The value that the preambleSfd field should take

   */

  void SetPreambleSfd (uint64_t preambleSfd);

  /**

   * \return The size of the payload in bytes

   */

  uint16_t GetLengthType (void) const;

  /**

   * \return The type of packet (only basic Ethernet is currently supported)

   */

  ethernet_header_t GetPacketType (void) const;

  /**

   * \return The source address of this packet

   */

  /**

   * \return The destination address of this packet

   */

  /**

   * \return The value of the PreambleSfd field

   */

  uint64_t GetPreambleSfd () const;

  /**

   * \return The size of the header

   */

  uint32_t GetHeaderSize() const;

  std::string GetName (void) const;

  void Print (std::ostream &os) const;

  uint32_t GetSerializedSize (void) const;

  void Serialize (Buffer::Iterator start) const;

  uint32_t Deserialize (Buffer::Iterator start);

private:

  static const int PREAMBLE_SIZE = 8; /// size of the preamble_sfd header field

  static const int LENGTH_SIZE = 2;   /// size of the length_type header field

  static const int MAC_ADDR_SIZE = 6; /// size of src/dest addr header fields

  /**

   * If false, the preamble/sfd are not serialised/deserialised.

   */

  bool m_enPreambleSfd;

  uint64_t m_preambleSfd;     /// Value of the Preamble/SFD fields

  uint16_t m_lengthType;      /// Length or type of the packet

};

}; // namespace ns3

#endif /* ETHERNET_HEADER_H */