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

/*

 * Copyright (c) 2008,2009 IITP RAS

 *

 * 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

 *

 * Authors: Kirill Andreev <andreev@iitp.ru>

 *          Aleksey Kovalenko <kovalenko@iitp.ru>

 */

#ifndef WIFI_PEER_MAN_H

#define WIFI_PEER_MAN_H

#include "ns3/mac48-address.h"

#include "ns3/wifi-net-device.h"

#include "ns3/ie-dot11s-peer-management.h"

#include "ns3/ie-dot11s-beacon-timing.h"

#include "ns3/mesh-wifi-mac.h"

#include <list>

namespace ns3 {

class MeshWifiMac;

/**

 * \ingroup mesh

 */

class WifiPeerLinkDescriptorDUP : public RefCountBase

{

public:

  WifiPeerLinkDescriptorDUP ();

  /**

   * Beacon loss processing:

   */

  void  SetBeaconInformation (Time lastBeacon, Time BeaconInterval);

  void  SetMaxBeaconLoss (uint8_t maxBeaconLoss);

  /**

   * \brief Methods used to detecet peer link changes

   * \param bool if true - opened new link, if

   * false - link closed

   */

  void  SetLinkStatusCallback (Callback<void, Mac48Address, Mac48Address, bool> cb);

  /**

   * Peer link geeters/setters

   */

  void  SetPeerAddress (Mac48Address macaddr);

  /**

   * Debug purpose

   */

  void  SetLocalAddress (Mac48Address macaddr);

  void  SetLocalLinkId  (uint16_t id);

  void  SetPeerLinkId   (uint16_t id);

  void  SetLocalAid     (uint16_t aid);

  void  SetPeerAid      (uint16_t aid);

  void  SetBeaconTimingElement (IeDot11sBeaconTiming beaconTiming);

  void  SetPeerLinkDescriptorDUPElement (IeDot11sPeerManagement peerLinkElement);

  Mac48Address GetPeerAddress () const;

  /**

   * Debug purpose

   */

  Mac48Address GetLocalAddress () const;

  uint16_t GetLocalAid () const;

  Time  GetLastBeacon () const;

  Time  GetBeaconInterval () const;

  IeDot11sBeaconTiming    GetBeaconTimingElement () const;

  IeDot11sPeerManagement  GetPeerLinkDescriptorDUPElement () const;

  void  ClearTimingElement ();

  /* MLME */

  void  MLMECancelPeerLink (dot11sReasonCode reason);

  void  MLMEPassivePeerLinkOpen ();

  void  MLMEActivePeerLinkOpen ();

  void  MLMEPeeringRequestReject ();

#if 0

  void  MLMEBindSecurityAssociation ();

#endif

  void  SetMac (Ptr<MeshWifiMac> mac);

  void  PeerLinkClose (uint16_t localLinkID,uint16_t peerLinkID, dot11sReasonCode reason);

  void  PeerLinkOpenAccept (uint16_t localLinkId, IeDot11sConfiguration  conf);

  void  PeerLinkOpenReject (uint16_t localLinkId, IeDot11sConfiguration  conf, dot11sReasonCode reason);

  void  PeerLinkConfirmAccept (

    uint16_t localLinkId,

    uint16_t peerLinkId,

    uint16_t peerAid,

    IeDot11sConfiguration  conf

  );

  void  PeerLinkConfirmReject (

    uint16_t localLinkId,

    uint16_t peerLinkId,

    IeDot11sConfiguration  conf,

    dot11sReasonCode reason

  );

  bool  LinkIsEstab () const;

  bool  LinkIsIdle  () const;

private:

  enum  PeerState {

    IDLE,

    LISTEN,

    OPN_SNT,

    CNF_RCVD,

    OPN_RCVD,

    ESTAB,

    HOLDING,

  };

  enum  PeerEvent

  {

    CNCL,  /** MLME-CancelPeerLink */

    PASOPN,  /** MLME-PassivePeerLinkOpen */

    ACTOPN,  /** MLME-ActivePeerLinkOpen */

    //BNDSA,     /** MLME-BindSecurityAssociation */

    CLS_ACPT, /** PeerLinkClose_Accept */

    //CLS_IGNR, /** PeerLinkClose_Ignore */

    OPN_ACPT, /** PeerLinkOpen_Accept */

    //OPN_IGNR, /** PeerLinkOpen_Ignore */

    OPN_RJCT, /** PeerLinkOpen_Reject */

    REQ_RJCT, /** PeerLinkOpenReject by internal reason */

    CNF_ACPT, /** PeerLinkConfirm_Accept */

    //CNF_IGNR, /** PeerLinkConfirm_Ignore */

    CNF_RJCT, /** PeerLinkConfirm_Reject */

    TOR1,

    TOR2,

    TOC,

    TOH,

  };

private:

  void StateMachine (PeerEvent event,dot11sReasonCode = REASON11S_RESERVED);

  /** Events handlers */

  void ClearRetryTimer   ();

  void ClearConfirmTimer ();

  void ClearHoldingTimer ();

  void SetHoldingTimer   ();

  void SetRetryTimer     ();

  void SetConfirmTimer   ();

  void SendPeerLinkClose (dot11sReasonCode reasoncode);

  void SendPeerLinkOpen ();

  void SendPeerLinkConfirm ();

  /** Private Event */

  void HoldingTimeout ();

  void RetryTimeout   ();

  void ConfirmTimeout ();

private:

  Mac48Address m_peerAddress;

  Mac48Address m_localAddress;

  uint16_t m_localLinkId;

  uint16_t m_peerLinkId;

  // Used for beacon timing:

  // All values are stored in microseconds!

  Time  m_lastBeacon;

  Time  m_beaconInterval;

  uint16_t m_assocId; //Assigned Assoc ID

  uint16_t m_peerAssocId; //Assoc Id assigned to me by peer

  //State of our peer Link:

  PeerState m_state;

  IeDot11sConfiguration  m_configuration;

  // State is a bitfield as defined as follows:

  // This are states for a given

  IeDot11sBeaconTiming  m_beaconTiming;

  EventId  m_retryTimer;

  EventId  m_holdingTimer;

  EventId  m_confirmTimer;

  uint16_t m_retryCounter;

  /**

   * Beacon loss timers:

   */

  EventId  m_beaconLossTimer;

  uint8_t  m_maxBeaconLoss;

  void  BeaconLoss ();

  Ptr<MeshWifiMac> m_mac;

  Callback<void, Mac48Address, Mac48Address, bool>  m_linkStatusCallback;

};

/**

 * \ingroup mesh

 */

class WifiPeerManager : public Object

{

public:

  WifiPeerManager ();

  WifiPeerManager (Ptr<MeshWifiMac> mac_pointer);

  ~WifiPeerManager ();

  static TypeId GetTypeId ();

  //Returns a beacon timing element stored for remote station:

  IeDot11sBeaconTiming  GetIeDot11sBeaconTimingForAddress (Mac48Address portAddress, Mac48Address addr);

  //Returns a list of all addresses, which beacons can be decoded:

  std::vector<Mac48Address>  GetNeighbourAddressList (Mac48Address portAddress, Mac48Address peerAddress);

  bool AttachPorts (std::vector<Ptr<WifiNetDevice> >);

  //void SetMac (Ptr<MeshWifiMac> mac);

  Time GetNextBeaconShift (Mac48Address portAddress, Time myNextTBTT);

  void SetSentBeaconTimers (

    Mac48Address portAddress,

    Time  ReferenceTBTT,

    Time  BeaconInterval

  );

  void AskIfOpenNeeded (

    Mac48Address portAddress,

    Mac48Address peerAddress

  );

  void SetReceivedBeaconTimers (

    Mac48Address portAddress,

    Mac48Address peerAddress,

    Time  lastBeacon,

    Time  beaconInterval,

    IeDot11sBeaconTiming  beaconTiming

  );

  void SetOpenReceived (

    Mac48Address portAddress,

    Mac48Address peerAddress,

    IeDot11sPeerManagement peerMan,

    IeDot11sConfiguration conf

  );

  void SetConfirmReceived (

    Mac48Address portAddress,

    Mac48Address peerAddress,

    uint16_t peerAid,

    IeDot11sPeerManagement  peerMan,

    IeDot11sConfiguration meshConfig

  );

  void SetCloseReceived (

    Mac48Address portAddress,

    Mac48Address peerAddress,

    IeDot11sPeerManagement peerMan

  );

  //Using this function MAC

  void ConfigurationMismatch (

    Mac48Address portAddress,

    Mac48Address peerAddress

  );

  //Returns a beacon timing element to added into my beacon:

  IeDot11sBeaconTiming

  GetIeDot11sBeaconTimingForMyBeacon (

    Mac48Address portAddress

  );

  bool IsActiveLink (

    Mac48Address portAddress,

    Mac48Address peerAddress

  );

private:

  struct BeaconInfo

  {

    Time referenceTbtt; //When one of my station's beacons was put into a beacon queue;

    Time beaconInterval; //Beacon interval of my station;

  };

  typedef std::map<Mac48Address, std::vector<Ptr<WifiPeerLinkDescriptorDUP> >, std::less<Mac48Address> >  PeerDescriptorsMap;

  typedef std::map<Mac48Address, Ptr<MeshWifiMac>,std::less<Mac48Address> > MeshMacMap;

  typedef std::map<Mac48Address, BeaconInfo, std::less<Mac48Address> > BeaconInfoMap;

  //Ptr<MeshWifiMac> m_mac;

  //Maximum peers that may be opened:

  uint8_t  m_maxNumberOfPeerLinks;

  /**

   * Peer manager identify interface by address

   * of MAC. So, for every interface we store

   * list of peer descriptors.

   */

  PeerDescriptorsMap m_peerDescriptors;

  /**

   * List of MAC pointers - to iteract with each

   * mac

   */

  MeshMacMap m_macPointers;

  uint8_t  m_numberOfActivePeers; //number of established peer links

  uint16_t m_assocId;  //last stored assoc ID

  uint16_t m_localLinkId;  //last stored local link ID

  //This Variables used in beacon miss auto-cleanup:

  //How many beacons may we lose before the link is

  //considered to be broken:

  uint8_t  m_maxBeaconLoss;

  //Periodically we scan the peer manager list of peers

  //and check if the too many  beacons were lost:

  Time  m_peerLinkCleanupPeriod;

  EventId  m_cleanupEvent;

  Ptr<WifiPeerLinkDescriptorDUP> AddDescriptor (

    Mac48Address portAddress,

    Mac48Address peerAddress,

    Time lastBeacon,

    Time beaconInterval

  );

  void  PeerCleanup ();

  //Mechanism of choosing PEERs:

  bool  ShouldSendOpen (Mac48Address portAddress, Mac48Address peerAddress);

  bool  ShouldAcceptOpen (

    Mac48Address portAddress,

    Mac48Address peerAddress,

    dot11sReasonCode & reasonCode

  );

  //Needed for Beacon Collision Avoidance module:

  BeaconInfoMap m_myBeaconInfo;

  /**

   * Peer link Open/Close callbacks: We need to

   * inform MAC about this events.

   * \brief Interaction with peer link

   * descriptor - notify that peer link was

   * opened or closed

   * \param status true - peer link opened, peer

   * link closed otherwise

   */

  void PeerLinkStatus (Mac48Address portAddress, Mac48Address peerAddress, bool status);

};

} //namespace ns3

#endif