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

/* 

 * Copyright (c) 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>

 *          Pavel Boyko <boyko@iitp.ru>

 */

#ifndef MESHWIFIINTERFACEMAC_H_

#define MESHWIFIINTERFACEMAC_H_

#include <stdint.h>

#include <map>

#include "ns3/mac48-address.h"

#include "ns3/mgt-headers.h"

#include "ns3/callback.h"

#include "ns3/packet.h"

#include "ns3/nstime.h"

#include "ns3/wifi-remote-station-manager.h"

#include "ns3/wifi-mac.h"

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

#include "ns3/event-id.h"

namespace ns3 {

class WifiMacHeader;

class DcaTxop;

class WifiPhy;

class DcfManager;

class MacRxMiddle;

class MacLow;

/**

 * \ingroup mesh

 *

 * \brief Basic MAC of mesh point Wi-Fi interface. Its function is extendable through plugins mechanism.

 * 

 * Now only three output queues are used:

 *  - beacons (PIFS and no backoff),

 *  - background traffic,

 *  - management and priority traffic.

 *  

 */

class MeshWifiInterfaceMac : public WifiMac

{

public:

  /// Never forget to support typeid

  static TypeId  GetTypeId ();

  /// C-tor

  MeshWifiInterfaceMac ();

  /// D-tor

  virtual ~MeshWifiInterfaceMac ();

  ///\name Inherited from WifiMac

  //\{

  virtual void  SetSlot (Time slotTime);

  virtual void  SetSifs (Time sifs);

  virtual void  SetPifs (Time pifs);

  virtual void  SetCtsTimeout (Time ctsTimeout);

  virtual void  SetAckTimeout (Time ackTimeout);

  virtual void  SetEifsNoDifs (Time eifsNoDifs);

  virtual Time  GetSlot () const;

  virtual Time  GetSifs () const;

  virtual Time  GetPifs () const;

  virtual Time  GetCtsTimeout () const;

  virtual Time  GetAckTimeout () const;

  virtual Time  GetEifsNoDifs () const;

  virtual void  SetWifiPhy (Ptr<WifiPhy> phy);

  virtual void  SetWifiRemoteStationManager (Ptr<WifiRemoteStationManager> stationManager);

  virtual void  Enqueue (Ptr<const Packet> packet, Mac48Address to, Mac48Address from);

  virtual void  Enqueue (Ptr<const Packet> packet, Mac48Address to);

  virtual bool  SupportsSendFrom () const;

  virtual void  SetForwardUpCallback (Callback<void,Ptr<Packet>, Mac48Address, Mac48Address> upCallback);

  virtual void  SetLinkUpCallback (Callback<void> linkUp);

  virtual void  SetLinkDownCallback (Callback<void> linkDown);

  virtual Mac48Address GetAddress () const;

  virtual Mac48Address GetBssid () const;

  virtual Ssid  GetSsid () const;

  virtual void  SetAddress (Mac48Address address);

  virtual void  SetSsid (Ssid ssid);

  //\}

  ///\name Each mesh point interfaces must know the mesh point address

  //\{

  void SetMeshPointAddress (Mac48Address);

  Mac48Address GetMeshPointAddress () const;

  //\}

  ///\name Beacons

  //\{

  /// Set maximum initial random delay before first beacon

  void SetRandomStartDelay (Time interval);

  /// Set interval between two successive beacons

  void SetBeaconInterval (Time interval);

  /// \return interval between two beacons

  Time GetBeaconInterval () const;

  /** 

   * \brief Next beacon frame time

   * 

   * This is supposed to be used by any entity managing beacon collision avoidance (e.g. Peer management protocol in 802.11s)

   */ 

  Time GetTbtt () const;

  /**

   * \brief Shift TBTT.

   * 

   * This is supposed to be used by any entity managing beacon collision avoidance (e.g. Peer management protocol in 802.11s)

   * 

   * \attention User of ShiftTbtt () must take care to not shift it to the past. 

   */

  void ShiftTbtt (Time shift);

  //\}

  ///\name Plugins

  //\{

  /// Install plugin. TODO return unique ID to allow unregister plugins

  void InstallPlugin (Ptr<MeshWifiInterfaceMacPlugin> plugin);

  //\}

  /** \name Channel switching

   * 

   * Channel center frequency = Channel starting frequency + 5 * channel_id (MHz), 

   * where Starting channel frequency is standard-dependent as defined in IEEE 802.11-2007 17.3.8.3.2.

   * 

   * Number of channels to use must be limited elsewhere. 

   */

  //\{

  /// Return true if PHY layer can switch channels

  bool CanSwitchChannel () const;

  /// Current channel Id

  uint16_t GetFrequencyChannel () const;

  /// Switch channel

  void SwitchFrequencyChannel (uint16_t new_id);

  //\}

  /// To be used by plugins sending management frames.

  void SendManagementFrame(Ptr<Packet> frame, const WifiMacHeader& hdr);

  /// \return true if rates are supported

  bool CheckSupportedRates(SupportedRates rates) const;

  /// \return list of supported bitrates

  SupportedRates GetSupportedRates () const;

  ///\ name Metric Calculation routines:

  ///\{

  void SetLinkMetricCallback(Callback<uint32_t, Mac48Address, Ptr<MeshWifiInterfaceMac> > cb);

  uint32_t GetLinkMetric(Mac48Address peerAddress);

  Ptr<WifiRemoteStationManager> GetStationManager ();

  ///\}

  ///\brief Statistics:

  void Report (std::ostream &) const;

  void ResetStats ();

private:

  /// Frame receive handler

  void  Receive (Ptr<Packet> packet, WifiMacHeader const *hdr);

  /// Forward frame to mesh point

  virtual void ForwardUp (Ptr<Packet> packet, Mac48Address src, Mac48Address dst);

  /// Send frame. Frame is supposed to be tagged by routing information. TODO: clarify this point 

  void  ForwardDown (Ptr<const Packet> packet, Mac48Address from, Mac48Address to);

  /// Send beacon

  void SendBeacon ();

  /// Schedule next beacon

  void ScheduleNextBeacon ();

  /// Enable/disable beacons

  void SetBeaconGeneration (bool enable);

  /// Get current beaconing status

  bool GetBeaconGeneration () const;

  /// Real d-tor

  virtual void DoDispose ();

private:

  ///\name Wifi MAC internals

  //\{

  Ptr<DcaTxop>   m_BE;

  Ptr<DcaTxop>   m_BK;

  Ptr<DcaTxop>   m_VI;

  Ptr<DcaTxop>   m_VO;

  Ptr<DcaTxop>   m_beaconDca;

  Ptr<WifiRemoteStationManager> m_stationManager;

  Ptr<WifiPhy>   m_phy;

  Callback<void, Ptr<Packet>, Mac48Address, Mac48Address>  m_upCallback;

  //\}

  ///\name Wifi timing intervals

  //\{

  Time m_slot;

  Time m_sifs;

  Time m_pifs;

  Time m_ackTimeout;

  Time m_ctsTimeout;

  Time m_eifsNoDifs;

  //\}

  ///\name Mesh timing intervals 

  //\{

  /// Beaconing interval.

  Time m_beaconInterval;

  /// Maximum delay before first beacon

  Time m_randomStart;

  /// Time for the next frame

  Time m_tbtt;

  //\}

  /// DCF implementation

  DcfManager* m_dcfManager;

  /// Middle MAC sublayer

  MacRxMiddle* m_rxMiddle;

  /// Low MAC sublayer

  Ptr<MacLow> m_low;

  /// My address

  Mac48Address m_address;

  /// Mesh point address

  Mac48Address m_mpAddress;

  /// SSID

  Ssid m_meshId;

  /// "Timer" for the next beacon 

  EventId m_beaconSendEvent;

  typedef std::vector< Ptr<MeshWifiInterfaceMacPlugin> > PluginList; 

  /// List of all installed plugins

  PluginList m_plugins;

  Callback<uint32_t, Mac48Address, Ptr<MeshWifiInterfaceMac> > m_linkMetricCallback;

  ///\name Statistics:

  ///\{

  struct Statistics

  {

    uint16_t recvBeacons;

    uint32_t sentFrames;

    uint32_t sentBytes;

    uint32_t recvFrames;

    uint32_t recvBytes;

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

    Statistics () :

      recvBeacons (0),

      sentFrames (0),

      sentBytes (0),

      recvFrames (0),

      recvBytes (0)

      {}

  };

  Statistics m_stats;

  ///\}

};

} // namespace ns3

#endif /* MESHWIFIINTERFACEMAC_H_ */