/* -*-  Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil; -*- */
/*
 * Copyright (c) 2004 Francisco J. Ros 
 * Copyright (c) 2007 INESC Porto
 *
 * 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: Francisco J. Ros  <fjrm@dif.um.es>
 *          Gustavo J. A. M. Carneiro <gjc@inescporto.pt>
 */


#ifndef __OLSR_AGENT_IMPL_H__
#define __OLSR_AGENT_IMPL_H__

#include <vector>

#include "olsr-agent.h"
#include "olsr-header.h"
#include "olsr-state.h"

#include "routing-table.h"
#include "repositories.h"

#include "ns3/object.h"
#include "ns3/packet.h"
#include "ns3/node.h"
#include "ns3/socket.h"
#include "event-garbage-collector.h"
#include "ns3/timer.h"
#include "ns3/callback-trace-source.h"


namespace ns3 {
namespace olsr {


class AgentImpl : public Agent
{
public:
  AgentImpl (Ptr<Node> node);

  virtual void Start ();
  virtual void SetMainInterface (uint32_t interface);

private:
  EventGarbageCollector m_events;

  /// Address of the routing agent.
  Ipv4Address m_routingAgentAddr;
	
  /// Packets sequence number counter.
  uint16_t m_packetSequenceNumber;
  /// Messages sequence number counter.
  uint16_t m_messageSequenceNumber;
  /// Advertised Neighbor Set sequence number.
  uint16_t m_ansn;
  
  /// HELLO messages' emission interval.
  Time m_helloInterval;
  /// TC messages' emission interval.
  Time m_tcInterval;
  /// MID messages' emission interval.
  Time m_midInterval;
  /// Willingness for forwarding packets on behalf of other nodes.
  uint8_t m_willingness;
  /// Determines if layer 2 notifications are enabled or not.
  bool m_useL2Notifications;
	
  /// Routing table.
  Ptr<RoutingTable> m_routingTable;
  /// Internal state with all needed data structs.
  OlsrState m_state;

  Ptr<Ipv4> m_ipv4;
	
protected:
  void DoDispose ();
  Ptr<TraceResolver> GetTraceResolver (void) const;

  void SendPacket (Ptr<Packet> packet, const MessageList &containedMessages);
	
  /// Increments packet sequence number and returns the new value.
  inline uint16_t GetPacketSequenceNumber ();
  /// Increments message sequence number and returns the new value.
  inline uint16_t GetMessageSequenceNumber ();
	
  void RecvOlsr (Ptr<Socket> socket,
                 Ptr<Packet> receivedPacket,
                 const Address &sourceAddress);

  void MprComputation ();
  void RoutingTableComputation ();
  Ipv4Address GetMainAddress (Ipv4Address iface_addr) const;

  // Timer handlers
  Timer m_helloTimer;
  void HelloTimerExpire ();
  
  Timer m_tcTimer;
  void TcTimerExpire ();

  Timer m_midTimer;
  void MidTimerExpire ();

  void DupTupleTimerExpire (DuplicateTuple tuple);
  bool m_linkTupleTimerFirstTime;
  void LinkTupleTimerExpire (LinkTuple tuple);
  void Nb2hopTupleTimerExpire (TwoHopNeighborTuple tuple);
  void MprSelTupleTimerExpire (MprSelectorTuple tuple);
  void TopologyTupleTimerExpire (TopologyTuple tuple);
  void IfaceAssocTupleTimerExpire (IfaceAssocTuple tuple);

  /// A list of pending messages which are buffered awaiting for being sent.
  olsr::MessageList m_queuedMessages;
  Timer m_queuedMessagesTimer; // timer for throttling outgoing messages

  void ForwardDefault (olsr::MessageHeader olsrMessage,
                       DuplicateTuple *duplicated,
                       const Ipv4Address &localIface,
                       const Ipv4Address &senderAddress);
  void QueueMessage (const olsr::MessageHeader &message, Time delay);
  void SendQueuedMessages ();
  void SendHello ();
  void SendTc ();
  void SendMid ();

  void NeighborLoss (const LinkTuple &tuple);
  void AddDuplicateTuple (const DuplicateTuple &tuple);
  void RemoveDuplicateTuple (const DuplicateTuple &tuple);
  LinkTuple & AddLinkTuple (const LinkTuple &tuple, uint8_t willingness);
  void RemoveLinkTuple (const LinkTuple &tuple);
  void LinkTupleUpdated (const LinkTuple &tuple);
  void AddNeighborTuple (const NeighborTuple &tuple);
  void RemoveNeighborTuple (const NeighborTuple &tuple);
  void AddTwoHopNeighborTuple (const TwoHopNeighborTuple &tuple);
  void RemoveTwoHopNeighborTuple (const TwoHopNeighborTuple &tuple);
  void AddMprSelectorTuple (const MprSelectorTuple  &tuple);
  void RemoveMprSelectorTuple (const MprSelectorTuple &tuple);
  void AddTopologyTuple (const TopologyTuple &tuple);
  void RemoveTopologyTuple (const TopologyTuple &tuple);
  void AddIfaceAssocTuple (const IfaceAssocTuple &tuple);
  void RemoveIfaceAssocTuple (const IfaceAssocTuple &tuple);

  void ProcessHello (const olsr::MessageHeader &msg,
                     const Ipv4Address &receiverIface,
                     const Ipv4Address &senderIface);
  void ProcessTc (const olsr::MessageHeader &msg,
                  const Ipv4Address &senderIface);
  void ProcessMid (const olsr::MessageHeader &msg,
                   const Ipv4Address &senderIface);

  void LinkSensing (const olsr::MessageHeader &msg,
                    const olsr::MessageHeader::Hello &hello,
                    const Ipv4Address &receiverIface,
                    const Ipv4Address &sender_iface);
  void PopulateNeighborSet (const olsr::MessageHeader &msg,
                            const olsr::MessageHeader::Hello &hello);
  void PopulateTwoHopNeighborSet (const olsr::MessageHeader &msg,
                                  const olsr::MessageHeader::Hello &hello);
  void PopulateMprSelectorSet (const olsr::MessageHeader &msg,
                               const olsr::MessageHeader::Hello &hello);

  int Degree (NeighborTuple const &tuple);

  Ipv4Address m_mainAddress;
  Ptr<Socket> m_receiveSocket; // UDP socket for receving OSLR packets
  Ptr<Socket> m_sendSocket; // UDP socket for sending OSLR packets

  CallbackTraceSource <const PacketHeader &,
                       const MessageList &> m_rxPacketTrace;
  CallbackTraceSource <const PacketHeader &,
                       const MessageList &> m_txPacketTrace;

};

}} // namespace ns3

#endif