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

/*

 * Copyright (c) 2012 Centre Tecnologic de Telecomunicacions de Catalunya (CTTC)

 *

 * 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: Nicola Baldo <nbaldo@cttc.cat>

 */

#ifndef EPC_S11_SAP_H

#define EPC_S11_SAP_H

#include <ns3/address.h>

#include <ns3/ptr.h>

#include <ns3/object.h>

#include <ns3/eps-bearer.h>

#include <ns3/epc-tft.h>

#include <list>

namespace ns3 {

class EpcS11Sap

{

public:

  virtual ~EpcS11Sap ();

  struct GtpcMessage

  {

    uint32_t teid;

  };

  /**

   * Fully-qualified TEID, see 3GPP TS 29.274 section 8.22

   * 

   */

  struct Fteid 

  {

    uint32_t teid;

    Ipv4Address address;

  };

  /**

   * TS 29.274 8.21  User Location Information (ULI)

   * 

   */

  struct Uli

  {

    uint16_t gci;

  };

};

/**

 * \ingroup lte

 *

 * MME side of the S11 Service Access Point (SAP), provides the MME

 * methods to be called when an S11 message is received by the MME. 

 */

class EpcS11SapMme : public EpcS11Sap

{

public:

 /**

   * 3GPP TS 29.274 version 8.3.1 Release 8 section 8.28

   * 

   */

  struct BearerContextCreated

  {

    EpcS11Sap::Fteid sgwFteid;

    uint8_t epsBearerId; 

    EpsBearer bearerLevelQos; 

    Ptr<EpcTft> tft;

  };

  /**     

   * Create Session Response message, see 3GPP TS 29.274 7.2.2

   */

  struct CreateSessionResponseMessage : public GtpcMessage

  {

    std::list<BearerContextCreated> bearerContextsCreated;

  };

  /** 

   * send a Create Session Response message

   * 

   * \param msg the message

   */

  virtual void CreateSessionResponse (CreateSessionResponseMessage msg) = 0;

  /**     

   * Modify Bearer Response message, see 3GPP TS 29.274 7.2.7

   */

  struct ModifyBearerResponseMessage : public GtpcMessage

  {

    enum Cause {

      REQUEST_ACCEPTED = 0,

      REQUEST_ACCEPTED_PARTIALLY,

      REQUEST_REJECTED,

      CONTEXT_NOT_FOUND

    } cause;

  };

  /** 

   * send a Modify Bearer Response message

   * 

   * \param msg the message

   */

  virtual void ModifyBearerResponse (ModifyBearerResponseMessage msg) = 0;

};

/**

 * \ingroup lte

 *

 * SGW side of the S11 Service Access Point (SAP), provides the SGW

 * methods to be called when an S11 message is received by the SGW. 

 */

class EpcS11SapSgw : public EpcS11Sap

{

public:

  struct BearerContextToBeCreated

  {    

    EpcS11Sap::Fteid sgwFteid;

    uint8_t epsBearerId; 

    EpsBearer bearerLevelQos; 

    Ptr<EpcTft> tft;

  };

  /**     

   * Create Session Request message, see 3GPP TS 29.274 7.2.1

   */

  struct CreateSessionRequestMessage : public GtpcMessage

  {

    uint64_t imsi; 

    Uli uli; 

    std::list<BearerContextToBeCreated> bearerContextsToBeCreated;    

  };

  /** 

   * send a Create Session Request message

   * 

   * \param msg the message

   */

  virtual void CreateSessionRequest (CreateSessionRequestMessage msg) = 0;

  /**     

   * Modify Bearer Request message, see 3GPP TS 29.274 7.2.7

   */

  struct ModifyBearerRequestMessage : public GtpcMessage

  {

    Uli uli;

  };

  /** 

   * send a Modify Bearer Request message

   * 

   * \param msg the message

   */

  virtual void ModifyBearerRequest (ModifyBearerRequestMessage msg) = 0;

};

/**

 * Template for the implementation of the EpcS11SapMme as a member

 * of an owner class of type C to which all methods are forwarded

 * 

 */

template <class C>

class MemberEpcS11SapMme : public EpcS11SapMme

{

public:

  MemberEpcS11SapMme (C* owner);

  // inherited from EpcS11SapMme

  virtual void CreateSessionResponse (CreateSessionResponseMessage msg);

  virtual void ModifyBearerResponse (ModifyBearerResponseMessage msg);

private:

  MemberEpcS11SapMme ();

  C* m_owner;

};

template <class C>

MemberEpcS11SapMme<C>::MemberEpcS11SapMme (C* owner)

  : m_owner (owner)

{

}

template <class C>

MemberEpcS11SapMme<C>::MemberEpcS11SapMme ()

{

}

template <class C>

void MemberEpcS11SapMme<C>::CreateSessionResponse (CreateSessionResponseMessage msg)

{

  m_owner->DoCreateSessionResponse (msg);

}

template <class C>

void MemberEpcS11SapMme<C>::ModifyBearerResponse (ModifyBearerResponseMessage msg)

{

  m_owner->DoModifyBearerResponse (msg);

}

/**

 * Template for the implementation of the EpcS11SapSgw as a member

 * of an owner class of type C to which all methods are forwarded

 * 

 */

template <class C>

class MemberEpcS11SapSgw : public EpcS11SapSgw

{

public:

  MemberEpcS11SapSgw (C* owner);

  // inherited from EpcS11SapSgw

  virtual void CreateSessionRequest (CreateSessionRequestMessage msg);

  virtual void ModifyBearerRequest (ModifyBearerRequestMessage msg);

private:

  MemberEpcS11SapSgw ();

  C* m_owner;

};

template <class C>

MemberEpcS11SapSgw<C>::MemberEpcS11SapSgw (C* owner)

  : m_owner (owner)

{

}

template <class C>

MemberEpcS11SapSgw<C>::MemberEpcS11SapSgw ()

{

}

template <class C>

void MemberEpcS11SapSgw<C>::CreateSessionRequest (CreateSessionRequestMessage msg)

{

  m_owner->DoCreateSessionRequest (msg);

}

template <class C>

void MemberEpcS11SapSgw<C>::ModifyBearerRequest (ModifyBearerRequestMessage msg)

{

  m_owner->DoModifyBearerRequest (msg);

}

} //namespace ns3

#endif /* EPC_S11_SAP_H */