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

/*

 * Copyright (c) 2009 University of Washington

 *

 * 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

 */

#ifndef IPV4_LIST_ROUTING_H

#define IPV4_LIST_ROUTING_H

#include <list>

#include "ns3/ipv4-routing-protocol.h"

namespace ns3 {

/**

 * \ingroup ipv4Routing 

 *

 * This class is a specialization of Ipv4RoutingProtocol that allows 

 * other instances of Ipv4RoutingProtocol to be inserted in a 

 * prioritized list.  Routing protocols in the list are consulted one

 * by one, from highest to lowest priority, until a routing protocol

 * is found that will take the packet (this corresponds to a non-zero

 * return value to RouteOutput, or a return value of true to RouteInput).

 * The order by which routing protocols with the same priority value 

 * are consulted is undefined.

 * 

 */

class Ipv4ListRouting : public Ipv4RoutingProtocol

{

public:

  static TypeId GetTypeId (void);

  Ipv4ListRouting ();  

  virtual ~Ipv4ListRouting ();  

  /**

   * \brief Register a new routing protocol to be used in this IPv4 stack

   *

   * \param routingProtocol new routing protocol implementation object

   * \param priority priority to give to this routing protocol.

   * Values may range between -32768 and +32767.  

   */

  virtual void AddRoutingProtocol (Ptr<Ipv4RoutingProtocol> routingProtocol, int16_t priority);

  /**

   * \return number of routing protocols in the list

   */

  virtual uint32_t GetNRoutingProtocols (void) const;

  /**

   * Return pointer to routing protocol stored at index, with the

   * first protocol (index 0) the highest priority, the next one (index 1)

   * the second highest priority, and so on.  The priority parameter is an

   * output parameter and it returns the integer priority of the protocol.

   * 

   * \return pointer to routing protocol indexed by 

   * \param index index of protocol to return

   * \param priority output parameter, set to the priority of the protocol

            being returned

   */

  virtual Ptr<Ipv4RoutingProtocol> GetRoutingProtocol (uint32_t index, int16_t& priority) const;

  // Below are from Ipv4RoutingProtocol

  virtual Ptr<Ipv4Route> RouteOutput (Ptr<Packet> p, const Ipv4Header &header, uint32_t 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 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);

  virtual void SetIpv4 (Ptr<Ipv4> ipv4);

protected:

  void DoDispose (void);

private:

  typedef std::pair<int16_t, Ptr<Ipv4RoutingProtocol> > Ipv4RoutingProtocolEntry;

  typedef std::list<Ipv4RoutingProtocolEntry> Ipv4RoutingProtocolList;

  Ipv4RoutingProtocolList m_routingProtocols;

  static bool Compare (const Ipv4RoutingProtocolEntry& a, const Ipv4RoutingProtocolEntry& b);

  Ptr<Ipv4> m_ipv4;

};

} //namespace ns3

#endif /* IPV4_LIST_ROUTING_H */