/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/**
 * Copyright (c) 2014,  Regents of the University of California,
 *                      Arizona Board of Regents,
 *                      Colorado State University,
 *                      University Pierre & Marie Curie, Sorbonne University,
 *                      Washington University in St. Louis,
 *                      Beijing Institute of Technology,
 *                      The University of Memphis
 *
 * This file is part of NFD (Named Data Networking Forwarding Daemon).
 * See AUTHORS.md for complete list of NFD authors and contributors.
 *
 * NFD is free software: you can redistribute it and/or modify it under the terms
 * of the GNU General Public License as published by the Free Software Foundation,
 * either version 3 of the License, or (at your option) any later version.
 *
 * NFD 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
 * NFD, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
 *
 * \author Ilya Moiseenko <http://ilyamoiseenko.com/>
 * \author Junxiao Shi <http://www.cs.arizona.edu/people/shijunxiao/>
 * \author Alexander Afanasyev <http://lasr.cs.ucla.edu/afanasyev/index.html>
 */

#ifndef NFD_DAEMON_TABLE_CS_ENTRY_HPP
#define NFD_DAEMON_TABLE_CS_ENTRY_HPP

#include "common.hpp"

namespace nfd {
namespace cs {

class Entry;

/** \brief represents a base class for CS entry
 */
class Entry : noncopyable
{
public:
  Entry();

  /** \brief returns the name of the Data packet stored in the CS entry
   *  \return{ NDN name }
   */
  const Name&
  getName() const;

  /** \brief returns the full name (including implicit digest) of the Data packet stored
   *         in the CS entry
   *  \return{ NDN name }
   */
  const Name&
  getFullName() const;

  /** \brief Data packet is unsolicited if this particular NDN node
   *  did not receive an Interest packet for it, or the Interest packet has already expired
   *  \return{ True if the Data packet is unsolicited; otherwise False  }
   */
  bool
  isUnsolicited() const;

  /** \brief returns the Data packet stored in the CS entry
   */
  const Data&
  getData() const;

  /** \brief changes the content of CS entry and recomputes digest
   */
  void
  setData(const Data& data, bool isUnsolicited);

  /** \brief returns the absolute time when Data becomes expired
   *  \return{ Time (resolution up to time::milliseconds) }
   */
  const time::steady_clock::TimePoint&
  getStaleTime() const;

  /** \brief refreshes the time when Data becomes expired
   *  according to the current absolute time.
   */
  void
  updateStaleTime();

  /** \brief checks if the stored Data is stale
   */
  bool
  isStale() const;

  /** \brief clears CS entry
   *  After reset, *this == Entry()
   */
  void
  reset();

private:
  time::steady_clock::TimePoint m_staleAt;
  shared_ptr<const Data> m_dataPacket;

  bool m_isUnsolicited;
};

inline const Name&
Entry::getName() const
{
  BOOST_ASSERT(m_dataPacket != nullptr);
  return m_dataPacket->getName();
}

inline const Name&
Entry::getFullName() const
{
  BOOST_ASSERT(m_dataPacket != nullptr);
  return m_dataPacket->getFullName();
}

inline const Data&
Entry::getData() const
{
  BOOST_ASSERT(m_dataPacket != nullptr);
  return *m_dataPacket;
}

inline bool
Entry::isUnsolicited() const
{
  return m_isUnsolicited;
}

inline const time::steady_clock::TimePoint&
Entry::getStaleTime() const
{
  return m_staleAt;
}

} // namespace cs
} // namespace nfd

#endif // NFD_DAEMON_TABLE_CS_ENTRY_HPP