/* -*- Mode: C++; c-file-style: "gnu"; indent-tabs-mode:nil -*- */
/*
 * Copyright (c) 2012-2014 University of California, Los Angeles
 *
 * This file is part of ChronoSync, synchronization library for distributed realtime
 * applications for NDN.
 *
 * ChronoSync 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.
 *
 * ChronoSync 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
 * ChronoSync, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
 *
 * @author Zhenkai Zhu <http://irl.cs.ucla.edu/~zhenkai/>
 * @author Chaoyi Bian <bcy@pku.edu.cn>
 * @author Alexander Afanasyev <http://lasr.cs.ucla.edu/afanasyev/index.html>
 */

#include "sync-full-state.h"

#include <boost/make_shared.hpp>
#include <boost/lambda/lambda.hpp>
#include <boost/lambda/bind.hpp>
#include <boost/foreach.hpp>
#include <boost/assert.hpp>

#include "sync-full-leaf.h"

using namespace boost;
namespace ll = boost::lambda;

namespace Sync {


FullState::FullState ()
// m_lastUpdated is initialized to "not_a_date_time" in normal lib mode and to "0" time in NS-3 mode
{
}

FullState::~FullState ()
{
}

ndn::time::system_clock::Duration
FullState::getTimeFromLastUpdate () const
{
  return ndn::time::system_clock::now() - m_lastUpdated;
}

DigestConstPtr
FullState::getDigest ()
{
  if (!m_digest)
    {
      m_digest = make_shared<Digest> ();
      if (m_leaves.get<ordered> ().size () > 0)
        {
          BOOST_FOREACH (LeafConstPtr leaf, m_leaves.get<ordered> ())
            {
              FullLeafConstPtr fullLeaf = dynamic_pointer_cast<const FullLeaf> (leaf);
              BOOST_ASSERT (fullLeaf != 0);
              *m_digest << fullLeaf->getDigest ();
            }
          m_digest->finalize ();
        }
      else
        {
          std::istringstream is ("00"); //zero state
          is >> *m_digest;
        }
    }

  return m_digest;
}

// from State
boost::tuple<bool/*inserted*/, bool/*updated*/, SeqNo/*oldSeqNo*/>
FullState::update (NameInfoConstPtr info, const SeqNo &seq)
{
  m_lastUpdated = ndn::time::system_clock::now();


  m_digest.reset ();

  LeafContainer::iterator item = m_leaves.find (info);
  if (item == m_leaves.end ())
    {
      m_leaves.insert (make_shared<FullLeaf> (info, cref (seq)));
      return make_tuple (true, false, SeqNo ());
    }
  else
    {
      if ((*item)->getSeq () == seq || seq < (*item)->getSeq ())
        {
          return make_tuple (false, false, SeqNo ());
        }

      SeqNo old = (*item)->getSeq ();
      m_leaves.modify (item,
                       ll::bind (&Leaf::setSeq, *ll::_1, seq));
      return make_tuple (false, true, old);
    }
}

bool
FullState::remove (NameInfoConstPtr info)
{
  m_lastUpdated = ndn::time::system_clock::now();

  m_digest.reset ();

  LeafContainer::iterator item = m_leaves.find (info);
  if (item != m_leaves.end ())
    {
      m_leaves.erase (item);
      return true;
    }
  else
    return false;
}

} // Sync