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

/*

 * Copyright (c) 2007 Georgia Tech Research Corporation

 *

 * 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: Raj Bhattacharjea <raj.b@gatech.edu>

 */

#ifndef TCP_L4_PROTOCOL_H

#define TCP_L4_PROTOCOL_H

#include <stdint.h>

#include "ns3/packet.h"

#include "ns3/ipv4-address.h"

#include "ns3/ptr.h"

#include "ns3/object-factory.h"

#include "ipv4-end-point-demux.h"

#include "ipv4-l4-protocol.h"

#include "ipv4-interface.h"

#include "tcp-socket-impl.h"

#include "tcp-header.h"

#include "tcp-typedefs.h"

namespace ns3 {

class Node;

class Socket;

class TcpHeader;

/**

 * \ingroup tcp

 * \brief A layer between the sockets interface and IP

 * 

 * This class allocates "endpoint" objects (ns3::Ipv4EndPoint) for TCP,

 * and SHOULD checksum packets its receives from the socket layer going down

 * the stack , but currently checksumming is disabled.  It also recieves 

 * packets from IP, and forwards them up to the endpoints.

*/

class TcpL4Protocol : public Ipv4L4Protocol {

public:

  static TypeId GetTypeId (void);

  static const uint8_t PROT_NUMBER;

  /**

   * \brief Constructor

   */

  TcpL4Protocol ();

  virtual ~TcpL4Protocol ();

  void SetNode (Ptr<Node> node);

  virtual int GetProtocolNumber (void) const;

  /**

   * \return A smart Socket pointer to a TcpSocketImpl, allocated by this instance

   * of the TCP protocol

   */

  Ptr<Socket> CreateSocket (void);

  Ipv4EndPoint *Allocate (void);

  Ipv4EndPoint *Allocate (Ipv4Address address);

  Ipv4EndPoint *Allocate (uint16_t port);

  Ipv4EndPoint *Allocate (Ipv4Address address, uint16_t port);

  Ipv4EndPoint *Allocate (Ipv4Address localAddress, uint16_t localPort,

                          Ipv4Address peerAddress, uint16_t peerPort);

  void DeAllocate (Ipv4EndPoint *endPoint);

//   // called by TcpSocketImpl.

//   bool Connect (const Ipv4Address& saddr, const Ipv4Address& daddr,

//                 uint16_t sport, uint16_t dport);

  /**

   * \brief Send a packet via TCP

   * \param packet The packet to send

   * \param saddr The source Ipv4Address

   * \param daddr The destination Ipv4Address

   * \param sport The source port number

   * \param dport The destination port number

   */

  void Send (Ptr<Packet> packet,

             Ipv4Address saddr, Ipv4Address daddr, 

             uint16_t sport, uint16_t dport);

  /**

   * \brief Recieve a packet up the protocol stack

   * \param p The Packet to dump the contents into

   * \param source The source's Ipv4Address

   * \param destination The destinations Ipv4Address

   * \param incomingInterface The Ipv4Interface it was received on

   */

  virtual enum Ipv4L4Protocol::RxStatus Receive (Ptr<Packet> p,

                                                 Ipv4Address const &source,

                                                 Ipv4Address const &destination,

                                                 Ptr<Ipv4Interface> incomingInterface);

protected:

  virtual void DoDispose (void);

  /* 

   * This function will notify other components connected to the node that a new stack member is now connected

   * This will be used to notify Layer 3 protocol of layer 4 protocol stack to connect them together.

   */

  virtual void NotifyNewAggregate ();

private:

  Ptr<Node> m_node;

  Ipv4EndPointDemux *m_endPoints;

  ObjectFactory m_rttFactory;

private:

  friend class TcpSocketImpl;

  void SendPacket (Ptr<Packet>, TcpHeader,

                  Ipv4Address, Ipv4Address);

  static ObjectFactory GetDefaultRttEstimatorFactory (void);

  std::vector<Ptr<TcpSocketImpl> > m_sockets;

};

}; // namespace ns3

#endif /* TCP_L4_PROTOCOL_H */