/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil -*- */
/*
 * Copyright (c) 2011 University of California, Los Angeles
 *
 * 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: Alexander Afanasyev <alexander.afanasyev@ucla.edu>
 */

#ifndef _CCNX_FIB_IMPL_H_
#define	_CCNX_FIB_IMPL_H_

#include "ns3/ccnx-fib.h"
#include "ns3/ccnx-name-components.h"

#include "../utils/trie-with-policy.h"
#include "../utils/empty-policy.h"

namespace ns3 {

class CcnxFibEntryImpl : public CcnxFibEntry
{
public:
  typedef ndnSIM::trie_with_policy<
    CcnxNameComponents,
    ndnSIM::smart_pointer_payload_traits<CcnxFibEntryImpl>,
    ndnSIM::empty_policy_traits
    > trie;

  CcnxFibEntryImpl (const Ptr<const CcnxNameComponents> &prefix)
    : CcnxFibEntry (prefix)
    , item_ (0)
  {
  }

  void
  SetTrie (trie::iterator item)
  {
    item_ = item;
  }

  trie::iterator to_iterator () { return item_; }
  trie::const_iterator to_iterator () const { return item_; }
  
private:
  trie::iterator item_;
};

struct CcnxFibEntryContainer
{
  typedef ndnSIM::trie_with_policy<
    CcnxNameComponents,
    ndnSIM::smart_pointer_payload_traits<CcnxFibEntryImpl>,
    ndnSIM::empty_policy_traits
    > type;
};

/**
 * \ingroup ccnx
 * \brief Class implementing FIB functionality
 */
class CcnxFibImpl : public CcnxFib,
                    private CcnxFibEntryContainer::type
{
public:
  typedef CcnxFibEntryContainer::type super;
  
  /**
   * \brief Interface ID
   *
   * \return interface ID
   */
  static TypeId GetTypeId ();

  /**
   * \brief Constructor
   */
  CcnxFibImpl ();

  /**
   * \brief Perform longest prefix match
   *
   * \todo Implement exclude filters
   *
   * \param interest Interest packet header
   * \returns If entry found a valid iterator will be returned, otherwise end ()
   */
  CcnxFib::iterator
  LongestPrefixMatch (const CcnxInterestHeader &interest) const;
  
  /**
   * \brief Add or update FIB entry
   *
   * If the entry exists, metric will be updated. Otherwise, new entry will be created
   *
   * Entries in FIB never deleted. They can be invalidated with metric==NETWORK_UNREACHABLE
   *
   * @param name	Prefix
   * @param face	Forwarding face
   * @param metric	Routing metric
   */
  CcnxFib::iterator
  Add (const CcnxNameComponents &prefix, Ptr<CcnxFace> face, int32_t metric);

  /**
   * \brief Add or update FIB entry using smart pointer to prefix
   *
   * If the entry exists, metric will be updated. Otherwise, new entry will be created
   *
   * Entries in FIB never deleted. They can be invalidated with metric==NETWORK_UNREACHABLE
   *
   * @param name	Smart pointer to prefix
   * @param face	Forwarding face
   * @param metric	Routing metric
   */
  CcnxFib::iterator
  Add (const Ptr<const CcnxNameComponents> &prefix, Ptr<CcnxFace> face, int32_t metric);

  /**
   * @brief Remove FIB entry
   *
   * ! ATTENTION ! Use with caution.  All PIT entries referencing the corresponding FIB entry will become invalid.
   * So, simulation may crash.
   *
   * @param name	Smart pointer to prefix
   */
  void
  Remove (const Ptr<const CcnxNameComponents> &prefix);

  // /**
  //  * @brief Invalidate FIB entry ("Safe" version of Remove)
  //  *
  //  * All faces for the entry will be assigned maximum routing metric and NDN_FIB_RED status   
  //  * @param name	Smart pointer to prefix
  //  */
  // void
  // Invalidate (const Ptr<const CcnxNameComponents> &prefix);

  /**
   * @brief Invalidate all FIB entries
   */
  void
  InvalidateAll ();
  
  /**
   * @brief Remove all references to a face from FIB.  If for some enty that face was the only element,
   * this FIB entry will be removed.
   */
  void
  RemoveFromAll (Ptr<CcnxFace> face);

  void
  Print (std::ostream &os) const;
  
  /**
   * @brief Modify element in container
   */
  template<typename Modifier>
  bool
  modify (CcnxFib::iterator item, Modifier mod)
  {
    return super::modify (StaticCast<CcnxFibEntryImpl> (item)->to_iterator (), mod);
  }
  
protected:
  // inherited from Object class
  virtual void NotifyNewAggregate (); ///< @brief Notify when object is aggregated
  virtual void DoDispose (); ///< @brief Perform cleanup

private:
  /**
   * @brief Remove reference to a face from the entry. If entry had only this face, the whole
   * entry will be removed
   */
  void
  Remove (super::parent_trie &item, Ptr<CcnxFace> face);
  
private:
  Ptr<Node> m_node;
};
 
} // namespace ns3

#endif	/* _CCNX_FIB_IMPL_H_ */