/* -*-  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>

 *          Pavel Boyko <boyko@iitp.ru>

 */

#ifndef HWMP_H

#define HWMP_H

#include <map>

#include <queue>

#include "ns3/tag.h"

#include "ns3/object.h"

#include "ns3/mac48-address.h"

#include "ns3/mesh-l2-routing-protocol.h"

#include "ns3/packet.h"

#include "ns3/hwmp-state.h"

namespace ns3 {

class HwmpState;

/**

 * \ingroup mesh

 *

 * \brief Hwmp tag implements interaction between HWMP

 * protocol and MeshWifiMac

 *

 * \details Hwmp tag keeps the following:

 * 1. When packet is passed from Hwmp to 11sMAC:

 *  - retransmitter address,

 *  - TTL value,

 * 2. When packet is passed to Hwmp from 11sMAC:

 *  - lasthop address,

 *  - TTL value,

 *  - metric value (metric of link is recalculated

 *  at each packet, but routing table stores metric

 *  obtained during path discovery procedure)

 */

class HwmpTag : public Tag

{

public:

  HwmpTag ();

  ~HwmpTag ();

  void  SetAddress (Mac48Address retransmitter);

  Mac48Address GetAddress ();

  void  SetTtl (uint8_t ttl);

  uint8_t GetTtl ();

  void  SetMetric (uint32_t metric);

  uint32_t GetMetric ();

  void  SetSeqno (uint32_t seqno);

  uint32_t GetSeqno ();

  void  DecrementTtl ();

  static  TypeId  GetTypeId ();

  virtual TypeId  GetInstanceTypeId () const;

  virtual uint32_t GetSerializedSize () const;

  virtual void  Serialize (TagBuffer i) const;

  virtual void  Deserialize (TagBuffer i);

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

private:

  Mac48Address m_address;

  uint8_t  m_ttl;

  uint32_t m_metric;

  uint32_t m_seqno;

};

/**

 * \ingroup mesh

 */

class Hwmp : public MeshL2RoutingProtocol

{

public:

  static TypeId GetTypeId ();

  Hwmp ();

  ~Hwmp ();

  void DoDispose ();

  //intheritedfrom L2RoutingProtocol

  /**

   * \brief L2Routing protocol base class metod

   *

   * \details Route resolving procedure consits

   * of the following steps:

   * 1. Find reactive route and send a packet.

   * 2. Find all ports which are operate in

   * 'Proactive' mode and find a proper default

   * routes. and send packet to all proactive

   * 'ports'.

   * 3. If there are ports which are operate in

   * reactive mode - queue packet and start

   * route reactive path discovery

   *

   * \bug Now packet is sent to the 'best root'

   * rather than to the best root at each port

   */

  bool RequestRoute (

    uint32_t  sourceIface,

    const Mac48Address source,

    const Mac48Address destination,

    Ptr<Packet>  packet,

    uint16_t  protocolType,

    MeshL2RoutingProtocol::RouteReplyCallback  routeReply

  );

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

  /**

   * \brief Disables port by index.

   * \details Needed for external modules like

   * clusterization.

   */

  void DisablePort (uint32_t port);

  /**

   * \brief enables port

   */

  void EnablePort (uint32_t port);

  /**

   * \brief Setting proative mode.

   * \details To enable proactive mode you must

   * set a root node. Choosing the route is made

   * in accordance with the following:

   *  1. Find 'reactive' route. If route is

   *  found - send a packet using this

   *  information

   *  2. If there is no reactive route -

   *  find proactive or 'default' route.

   * \attention Comparsion between proactive and

   * reactive routes is incorrect, because we

   * have metric to root MP in te first case and

   * metric to the destination in the second

   * case.

   * \param port is the port where proactive

   * mode should be activated

   */

  void SetRoot (uint32_t port);

  /**

   * \brief Disable root functionality at a

   * given port

   */

  void UnSetRoot (uint32_t port);

  /**

   * \brief HwmpState retrns to Hwmp class all

   * routing information obtained from all HWMP

   * action frames

   */

  void ObtainRoutingInformation (

    HwmpState::INFO info

  );

  /**

   * \brief Hwmp state noyifyes that neighbour

   * is dissapeared. Hwmp state knows about peer

   * failure from MAC

   */

  void PeerFailure (Mac48Address peerAddress);

  void SetMaxTtl (uint8_t ttl);

  uint8_t  GetMaxTtl ();

private:

  static const uint32_t MAX_SEQNO = 0xffffffff;

  //candidate queue is implemented inside the

  //protocol:

  void  SetMaxQueueSize (int maxPacketsPerDestination);

  int  m_maxQueueSize;

  bool  QueuePacket (MeshL2RoutingProtocol::QueuedPacket packet);

  MeshL2RoutingProtocol::QueuedPacket  DequeuePacket (Mac48Address dst);

  void  SendAllPossiblePackets (Mac48Address dst);

  std::map<Mac48Address, std::queue<QueuedPacket> >  m_rqueue;

  //devices and HWMP states:

  enum DeviceState {

    ENABLED,

    DISABLED

  };

  enum DeviceMode {

    REACTIVE,

    PROACTIVE,

    ROOT

  };

  std::vector<enum DeviceState>  m_states;

  std::vector<enum DeviceMode>   m_modes;

  std::vector<Ptr<HwmpState> >   m_hwmpStates;

  //Routing table:

  Ptr<HwmpRtable>  m_rtable;

  //Proactive routines:

  /**

   * \brief Set port state as proactive.

   * \details mode is supposed to be proactive

   * when proatcive PREQ with a valid

   * information was received.

   */

  void  SetProactive (uint32_t port);

  /**

   * \brief Checks if the port is root, if true

   * - no default routes must be used at this

   * port

   */

  bool  IsRoot (uint32_t port);

  /**

   * \brief Interaction with HwmpState class -

   * request for starting routing discover

   * procedure (reactive route discovery!)

   * \param Mac48Address is destination to be

   * resolved

   */

  std::vector< Callback<void, Mac48Address> >  m_requestCallback;

  /**

   * \brief Callback that shall be executed when

   * need to send Path error

   * \param std::vector<Mac48Address> is the

   * list of unreachable destinations

   * \param std::vector<Mac48Address> is

   * receivers of PERR

   */

  std::vector<Callback<void,std::vector<HwmpRtable::FailedDestination> > >  m_pathErrorCallback;

  void StartPathErrorProcedure (

    std::vector<HwmpRtable::FailedDestination> destinations,

    uint32_t port);

  /**

   * \brief HwmpState need to know where to

   * retransmit PERR, only HWMP knows how to

   * retransmit it (broadcast/unicast) and only

   * HWMP has accessto routing table

   */

  std::vector<Mac48Address>  GetRetransmittersForFailedDestinations (

    std::vector<HwmpRtable::FailedDestination> failedDest,

    uint32_t port);

  /**

   * \brief Needed by HwmpState to find routes in case

   * of intermediate reply and choosing the

   * better route

   *

   */

  HwmpRtable::LookupResult  RequestRouteForAddress (const Mac48Address& destination);

  HwmpRtable::LookupResult  RequestRootPathForPort (uint32_t port);

  /**

   * \attention mesh seqno is processed at HWMP

   */

  uint32_t m_seqno;

  std::map<Mac48Address, uint32_t/**/>  m_seqnoDatabase;

  //Timers:

  /**

   * /brief checks when last preq was initiated, returns

   * false when retry has not expired

   */

  bool  ShouldSendPreq (Mac48Address dst);

  /**

   * \brief Generates PREQ retry when route is

   * still unresolved after first PREQ

   * If number of retries greater than

   * dot11sParameters::dot11MeshHWMPmaxPREQretries,

   * we return all packets to upper layers

   */

  void  RetryPathDiscovery (Mac48Address dst, uint8_t numOfRetry);

  /**

   * Keeps PREQ retry timers for every

   * destination

   */

  std::map<Mac48Address, EventId>  m_timeoutDatabase;

  /**

   * Configurable parameters:

   */

  uint8_t  m_maxTtl;

  bool     m_broadcastPerr;

};

} //namespace ns3

#endif