/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/*
 * Copyright (c) 2010 Lalith Suresh
 *
 * 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: Lalith Suresh <suresh.lalith@gmail.com>
 */

#ifndef IPV4_CLICK_ROUTING_H
#define IPV4_CLICK_ROUTING_H

#include "ns3/object.h"
#include "ns3/packet.h"
#include "ns3/ipv4.h"
#include "ns3/ipv4-routing-protocol.h"
#include "ns3/test.h"

#include <sys/time.h>
#include <sys/types.h>

#ifdef NS3_CLICK
#include <click/simclick.h>
#endif

#include <map>
#include <string>

namespace ns3 {

/**
* \defgroup click Click Routing
* This section documents the API of the ns-3 click module. For a generic functional description, please refer to the ns-3 manual.
*/

class UniformRandomVariable;

/**
* \ingroup click
* \brief Class to allow a node to use Click for external routing
*/

class Ipv4ClickRouting : public Ipv4RoutingProtocol
{
#ifdef NS3_CLICK
public:
  // Allow test cases to access private members
  friend class ClickTrivialTest;
  friend class ClickIfidFromNameTest;
  friend class ClickIpMacAddressFromNameTest;

  static TypeId GetTypeId (void);

  Ipv4ClickRouting ();
  virtual ~Ipv4ClickRouting ();

  Ptr<UniformRandomVariable> GetRandomVariable (void);
protected:
  virtual void DoInitialize (void);

public:
  virtual void DoDispose ();

  /**
  * \brief Click configuration file to be used by the node's Click Instance.
  * \param clickfile name of .click configuration file
  */
  void SetClickFile (std::string clickfile);

  /**
  * \brief Click defines to be used by the node's Click Instance.
  * \param defines mapping of defines for .click configuration file parsing
  */
  void SetDefines (std::map<std::string, std::string> defines);

  /**
   * \brief Name of the node as to be used by Click. Required for Click Dumps.
   * \param name Name to be assigned to the node.
   */
  void SetNodeName (std::string name);

  /**
   * \brief Name of the routing table element being used by Click. Required for RouteOutput ()
   * \param name Name of the routing table element.
   */
  void SetClickRoutingTableElement (std::string name);

  /**
   * \brief Read Handler interface for a node's Click Elements.
   *        Allows a user to read state information of a Click element.
   * \param elementName name of the Click element
   * \param handlerName name of the handler to be read
   */
  std::string ReadHandler (std::string elementName, std::string handlerName);

  /**
   * \brief Write Handler interface for a node's Click Elements
   *        Allows a user to modify state information of a Click element.
   * \param elementName name of the Click element
   * \param handlerName name of the handler to be read
   * \param writeString string to be written using the write handler
   */
  int WriteHandler (std::string elementName, std::string handlerName, std::string writeString);

  /**
   *
   * \brief Sets an interface to run on promiscuous mode.
   */
  void SetPromisc (int ifid);


private:
  simclick_node_t *m_simNode;

  /**
   * \brief Provide a mapping between the node reference used by Click and the corresponding Ipv4ClickRouting instance.
   */
  static std::map < simclick_node_t *, Ptr<Ipv4ClickRouting> > m_clickInstanceFromSimNode;

public:
  /**
   * \brief Allows the Click service methods, which reside outside Ipv4ClickRouting, to get the required Ipv4ClickRouting instances.
   * \param simnode The Click simclick_node_t instance for which the Ipv4ClickRouting instance is required
   * \return A Ptr to the required Ipv4ClickRouting instance
   */
  static Ptr<Ipv4ClickRouting> GetClickInstanceFromSimNode (simclick_node_t *simnode);

public:
  /**
   * \brief Provides for SIMCLICK_GET_DEFINES
   * \return The defines mapping for .click configuration file parsing
   */
  std::map<std::string, std::string> GetDefines (void);

  /**
   * \brief Provides for SIMCLICK_IFID_FROM_NAME
   * \param ifname The name of the interface
   * \return The interface ID which corresponds to ifname
   */
  int GetInterfaceId (const char *ifname);

  /**
   * \brief Provides for SIMCLICK_IPADDR_FROM_NAME
   * \param ifid The interface ID for which the IP Address is required
   * \return The IP Address of the interface in string format
   */
  std::string GetIpAddressFromInterfaceId (int ifid);

  /**
   * \brief Provides for SIMCLICK_IPPREFIX_FROM_NAME
   * \param ifid The interface ID for which the IP Prefix is required
   * \return The IP Prefix of the interface in string format
   */
  std::string GetIpPrefixFromInterfaceId (int ifid);

  /**
   * \brief Provides for SIMCLICK_MACADDR_FROM_NAME
   * \param ifid The interface ID for which the MAC Address is required
   * \return The MAC Address of the interface in string format
   */
  std::string GetMacAddressFromInterfaceId (int ifid);

  /**
   * \brief Provides for SIMCLICK_GET_NODE_NAME
   * \return The Node name
   */
  std::string GetNodeName ();

  /**
   * \brief Provides for SIMCLICK_IF_READY
   * \return Returns 1, if the interface is ready, -1 if ifid is invalid
   */
  bool IsInterfaceReady (int ifid);

  /**
   * \brief Set the Ipv4 instance to be used
   * \param ipv4 The Ipv4 instance
   */
  virtual void SetIpv4 (Ptr<Ipv4> ipv4);

private:
  /**
   * \brief Used internally in DoInitialize () to Add a mapping to m_clickInstanceFromSimNode mapping
   */
  void AddSimNodeToClickMapping ();

  /**
   * \brief Get current simulation time as a timeval
   */
  struct timeval GetTimevalFromNow () const;

  /**
   * \brief This method has to be scheduled everytime Click calls SIMCLICK_SCHEDULE
   */
  void RunClickEvent ();

public:
  /**
   * \brief Schedules simclick_click_run to run at the given time
   * \param when Time at which the simclick_click_run instance should be run
   */
  void HandleScheduleFromClick (const struct timeval *when);

  /**
   * \brief Receives a packet from Click
   * \param ifid The interface ID from which the packet is arriving
   * \param type The type of packet as defined in click/simclick.h
   * \param data The contents of the packet
   * \param len The length of the packet
   */
  void HandlePacketFromClick (int ifid, int type, const unsigned char *data, int len);

  /**
   * \brief Sends a packet to Click
   * \param ifid The interface ID from which the packet is arriving
   * \param type The type of packet as defined in click/simclick.h
   * \param data The contents of the packet
   * \param len The length of the packet
   */
  void SendPacketToClick (int ifid, int type, const unsigned char *data, int len);

  /**
   * \brief Allow a higher layer to send data through Click. (From Ipv4ExtRouting)
   * \param p The packet to be sent
   * \param src The source IP Address
   * \param dest The destination IP Address
   */
  void Send (Ptr<Packet> p, Ipv4Address src, Ipv4Address dest);

  /**
   * \brief Allow a lower layer to send data to Click. (From Ipv4ExtRouting)
   * \param p The packet to be sent
   * \param receiverAddr Receiving interface's address
   * \param dest The Destination MAC address
   */
  void Receive (Ptr<Packet> p, Mac48Address receiverAddr, Mac48Address dest);

  // From Ipv4RoutingProtocol
  virtual Ptr<Ipv4Route> RouteOutput (Ptr<Packet> p, const Ipv4Header &header, Ptr<NetDevice> oif, Socket::SocketErrno &sockerr);
  virtual bool RouteInput  (Ptr<const Packet> p, const Ipv4Header &header, Ptr<const NetDevice> idev,
                            UnicastForwardCallback ucb, MulticastForwardCallback mcb,
                            LocalDeliverCallback lcb, ErrorCallback ecb);
  virtual void PrintRoutingTable (Ptr<OutputStreamWrapper> stream) const;
  virtual void NotifyInterfaceUp (uint32_t interface);
  virtual void NotifyInterfaceDown (uint32_t interface);
  virtual void NotifyAddAddress (uint32_t interface, Ipv4InterfaceAddress address);
  virtual void NotifyRemoveAddress (uint32_t interface, Ipv4InterfaceAddress address);

private:
  std::string m_clickFile;
  std::map < std::string, std::string > m_defines;
  std::string m_nodeName;
  std::string m_clickRoutingTableElement;


  std::map < std::string, uint32_t > m_ifaceIdFromName;
  std::map < std::string, Address > m_ifaceMacFromName;
  std::map < std::string, Ipv4Address > m_ifaceAddrFromName;
  bool m_clickInitialised;
  bool m_nonDefaultName;

  Ptr<Ipv4> m_ipv4;
  Ptr<UniformRandomVariable> m_random;
#endif /* NS3_CLICK */
};

} // namespace ns3

#endif /* IPV4_CLICK_ROUTING_H */
