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

/*

 * Copyright (c) 2008 INRIA

 *

 * 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: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>

 */

#ifndef REGULAR_WIFI_MAC_H

#define REGULAR_WIFI_MAC_H

#include "ns3/wifi-mac.h"

#include "dca-txop.h"

#include "edca-txop-n.h"

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

#include "ssid.h"

#include "qos-utils.h"

#include <map>

namespace ns3 {

class Dcf;

class MacLow;

class MacRxMiddle;

class MacTxMiddle;

class DcfManager;

/**

 * \brief base class for all MAC-level wifi objects.

 *

 * This class encapsulates all the low-level MAC functionality

 * DCA, EDCA, etc) and all the high-level MAC functionality

 * (association/disassociation state machines).

 *

 */

class RegularWifiMac : public WifiMac

{

public:

  static TypeId GetTypeId (void);

  RegularWifiMac ();

  virtual ~RegularWifiMac ();

  /**

   * \param slotTime the slot duration

   */

  void SetSlot (Time slotTime);

  /**

   * \param sifs the sifs duration

   */

  void SetSifs (Time sifs);

  /**

   * \param eifsNoDifs the duration of an EIFS minus DIFS.

   *

   * This value is used to calculate the EIFS depending

   * on AIFSN.

   */

  void SetEifsNoDifs (Time eifsNoDifs);

  /**

   * \param pifs the pifs duration.

   */

  void SetPifs (Time pifs);

  /**

   * \param ctsTimeout the duration of a CTS timeout.

   */

  void SetCtsTimeout (Time ctsTimeout);

  /**

   * \param ackTimeout the duration of an ACK timeout.

   */

  void SetAckTimeout (Time ackTimeout);

  /**

   * \returns the current PIFS duration.

   */

  Time GetPifs (void) const;

  /**

   * \returns the current SIFS duration.

   */

  Time GetSifs (void) const;

  /**

   * \returns the current slot duration.

   */

  Time GetSlot (void) const;

  /**

   * \returns the current EIFS minus DIFS duration

   */

  Time GetEifsNoDifs (void) const;

  /**

   * \returns the current CTS timeout duration.

   */

  Time GetCtsTimeout (void) const;

  /**

   * \returns the current ACK timeout duration.

   */

  Time GetAckTimeout (void) const;

  /**

   * \returns the MAC address associated to this MAC layer.

   */

  virtual Mac48Address GetAddress (void) const;

  /**

   * \returns the ssid which this MAC layer is going to try to stay in.

   */

  virtual Ssid GetSsid (void) const;

  /**

   * \param address the current address of this MAC layer.

   */

  virtual void SetAddress (Mac48Address address);

  /**

   * \param ssid the current ssid of this MAC layer.

   */

  virtual void SetSsid (Ssid ssid);

  /**

   * \param bssid the BSSID of the network that this device belongs to.

   */

  virtual void SetBssid (Mac48Address bssid);

  /**

   * \returns the bssid of the network this device belongs to.

   */

  virtual Mac48Address GetBssid (void) const;

  /**

   * \param packet the packet to send.

   * \param to the address to which the packet should be sent.

   * \param from the address from which the packet should be sent.

   *

   * The packet should be enqueued in a tx queue, and should be

   * dequeued as soon as the channel access function determines that

   * access is granted to this MAC.  The extra parameter "from" allows

   * this device to operate in a bridged mode, forwarding received

   * frames without altering the source address.

   */

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

  virtual bool SupportsSendFrom (void) const;

  /**

   * \param packet the packet to send.

   * \param to the address to which the packet should be sent.

   *

   * The packet should be enqueued in a tx queue, and should be

   * dequeued as soon as the channel access function determines that

   * access is granted to this MAC.

   */

  virtual void Enqueue (Ptr<const Packet> packet, Mac48Address to) = 0;

  /**

   * \param phy the physical layer attached to this MAC.

   */

  virtual void SetWifiPhy (Ptr<WifiPhy> phy);

  /**

   * \returns the physical layer attached to this MAC.

   */

  virtual Ptr<WifiPhy> GetWifiPhy () const;

  /**

   * \param stationManager the station manager attached to this MAC.

   */

  virtual void SetWifiRemoteStationManager (Ptr<WifiRemoteStationManager> stationManager);

  /**

   * \returns the station manager attached to this MAC.

   */

  virtual Ptr<WifiRemoteStationManager> GetWifiRemoteStationManager () const;

  /**

   * This type defines the callback of a higher layer that a

   * WifiMac(-derived) object invokes to pass a packet up the stack.

   *

   * \param packet the packet that has been received.

   * \param from the MAC address of the device that sent the packet.

   * \param to the MAC address ot the device that the packet is

   * destined for.

   */

  typedef Callback<void, Ptr<Packet>, Mac48Address, Mac48Address> ForwardUpCallback;

  /**

   * \param upCallback the callback to invoke when a packet must be

   * forwarded up the stack.

   */

  virtual void SetForwardUpCallback (ForwardUpCallback upCallback);

  /**

   * \param linkUp the callback to invoke when the link becomes up.

   */

  virtual void SetLinkUpCallback (Callback<void> linkUp);

  /**

   * \param linkDown the callback to invoke when the link becomes down.

   */

  virtual void SetLinkDownCallback (Callback<void> linkDown);

  /* Next functions are not pure virtual so non Qos WifiMacs are not

   * forced to implement them.

   */

  virtual void SetBasicBlockAckTimeout (Time blockAckTimeout);

  virtual Time GetBasicBlockAckTimeout (void) const;

  virtual void SetCompressedBlockAckTimeout (Time blockAckTimeout);

  virtual Time GetCompressedBlockAckTimeout (void) const;

protected:

  virtual void DoStart ();

  virtual void DoDispose ();

  MacRxMiddle *m_rxMiddle;

  MacTxMiddle *m_txMiddle;

  Ptr<MacLow> m_low;

  DcfManager *m_dcfManager;

  Ptr<WifiPhy> m_phy;

  Ptr<WifiRemoteStationManager> m_stationManager;

  ForwardUpCallback m_forwardUp;

  Callback<void> m_linkUp;

  Callback<void> m_linkDown;

  Ssid m_ssid;

  /** This holds a pointer to the DCF instance for this WifiMac - used

  for transmission of frames to non-QoS peers. */

  Ptr<DcaTxop> m_dca;

  /** This type defines a mapping between an Access Category index,

  and a pointer to the corresponding channel access function */

  typedef std::map<AcIndex, Ptr<EdcaTxopN> > EdcaQueues;

  /** This is a map from Access Category index to the corresponding

  channel access function */

  EdcaQueues m_edca;

  /**

   * \param standard the phy standard to be used

   *

   * This method is called by ns3::WifiMac::ConfigureStandard to

   * complete the configuration process for a requested phy standard.

   *

   * This method may be overriden by a derived class (e.g., in order

   * to apply DCF or EDCA parameters specific to the usage model it is

   * dealing with), in which case the reimplementation may choose to

   * deal with certain values in the WifiPhyStandard enumeration, and

   * chain up to this implementation to deal with the remainder.

   */

  virtual void FinishConfigureStandard (enum WifiPhyStandard standard);

  /**

   * This method is invoked by a subclass to specify what type of

   * station it is implementing. This is something that the channel

   * access functions (instantiated within this class as EdcaTxopN's)

   * need to know.

   *

   * \param type the type of station.

   */

  void SetTypeOfStation (TypeOfStation type);

  /**

   * This method acts as the MacRxMiddle receive callback and is

   * invoked to notify us that a frame has been received. The

   * implementation is intended to capture logic that is going to be

   * common to all (or most) derived classes. Specifically, handling

   * of Block Ack managment frames is dealt with here.

   *

   * This method will need, however, to be overriden by derived

   * classes so that they can perform their data handling before

   * invoking the base version.

   *

   * \param packet the packet that has been received.

   * \param hdr a pointer to the MAC header of the received frame.

   */

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

  virtual void TxOk (const WifiMacHeader &hdr);

  virtual void TxFailed (const WifiMacHeader &hdr);

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

  /**

   * This method can be called to de-aggregate an A-MSDU and forward

   * the constituent packets up the stack.

   *

   * \param aggregatedPacket the Packet containing the A-MSDU.

   * \param hdr a pointer to the MAC header for \c aggregatedPacket.

   */

  virtual void DeaggregateAmsduAndForward (Ptr<Packet> aggregatedPacket,

                                           const WifiMacHeader *hdr);

  /**

   * This method can be called to accept a received ADDBA Request. An

   * ADDBA Response will be constructed and queued for transmission.

   *

   * \param reqHdr a pointer to the received ADDBA Request header.

   * \param originator the MAC address of the originator.

   */

  virtual void SendAddBaResponse (const MgtAddBaRequestHeader *reqHdr,

                                  Mac48Address originator);

  /**

   * This Boolean is set \c true iff this WifiMac is to model

   * 802.11e/WMM style Quality of Service. It is exposed through the

   * attribute system.

   *

   * At the moment, this flag is the sole selection between QoS and

   * non-QoS operation for the STA (whether IBSS, AP, or

   * non-AP). Ultimately, we will want a QoS-enabled STA to be able to

   * fall back to non-QoS operation with a non-QoS peer. This'll

   * require further intelligence - i.e., per-association QoS

   * state. Having a big switch seems like a good intermediate stage,

   * however.

   */

  bool m_qosSupported;

  /** Set accessor for the \c m_qosSupported member */

  void SetQosSupported (bool enable);

  /** Get accessor for the \c m_qosSupported member */

  bool GetQosSupported () const;

private:

  /**

   * This method is a private utility invoked to configure the channel

   * access function for the specified Access Category.

   *

   * \param ac the Access Category index of the queue to initialise.

   */

  void SetupEdcaQueue (enum AcIndex ac);

  /** Accessor for the DCF object */

  Ptr<DcaTxop> GetDcaTxop (void) const;

  /** Accessor for the AC_VO channel access function */

  Ptr<EdcaTxopN> GetVOQueue (void) const;

  /** Accessor for the AC_VI channel access function */

  Ptr<EdcaTxopN> GetVIQueue (void) const;

  /** Accessor for the AC_BE channel access function */

  Ptr<EdcaTxopN> GetBEQueue (void) const;

  /** Accessor for the AC_BK channel access function */

  Ptr<EdcaTxopN> GetBKQueue (void) const;

  TracedCallback<const WifiMacHeader &> m_txOkCallback;

  TracedCallback<const WifiMacHeader &> m_txErrCallback;

};

} // namespace ns3

#endif /* REGULAR_WIFI_MAC_H */