// $Id$

/***********************************************************************
Moses - factored phrase-based language decoder
Copyright (C) 2006 University of Edinburgh

This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.

This library 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
Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
***********************************************************************/

#include <algorithm>
#include "TargetPhraseCollection.h"
#include "util/exception.hh"

using namespace std;

namespace Moses
{
// helper for sort
bool
CompareTargetPhrase::
operator() (const TargetPhrase *a, const TargetPhrase *b) const
{
  return a->GetFutureScore() > b->GetFutureScore();
}

bool
CompareTargetPhrase::
operator() (const TargetPhrase &a, const TargetPhrase &b) const
{
  return a.GetFutureScore() > b.GetFutureScore();
}


TargetPhraseCollection::TargetPhraseCollection(const TargetPhraseCollection &copy)
{
  for (const_iterator iter = copy.begin(); iter != copy.end(); ++iter) {
    const TargetPhrase &origTP = **iter;
    TargetPhrase *newTP = new TargetPhrase(origTP);
    Add(newTP);
  }
}

void TargetPhraseCollection::NthElement(size_t tableLimit)
{
  CollType::iterator nth;
  nth = (tableLimit && tableLimit <= m_collection.size()
         ? m_collection.begin() + tableLimit
         : m_collection.end());
  NTH_ELEMENT4(m_collection.begin(), nth, m_collection.end(), CompareTargetPhrase());
}

void TargetPhraseCollection::Prune(bool adhereTableLimit, size_t tableLimit)
{
  NthElement(tableLimit);

  if (adhereTableLimit && m_collection.size() > tableLimit) {
    for (size_t ind = tableLimit; ind < m_collection.size(); ++ind) {
      const TargetPhrase *targetPhrase = m_collection[ind];
      delete targetPhrase;
    }
    m_collection.erase(m_collection.begin() + tableLimit, m_collection.end());
  }
}

void TargetPhraseCollection::Sort(bool adhereTableLimit, size_t tableLimit)
{
  CollType::iterator iterMiddle;
  iterMiddle = (tableLimit == 0 || m_collection.size() < tableLimit)
               ? m_collection.end()
               : m_collection.begin()+tableLimit;

  std::partial_sort(m_collection.begin(), iterMiddle, m_collection.end(),
                    CompareTargetPhrase());

  if (adhereTableLimit && tableLimit && m_collection.size() > tableLimit) {
    for (size_t i = tableLimit; i < m_collection.size(); ++i) {
      const TargetPhrase *targetPhrase = m_collection[i];
      delete targetPhrase;
    }
    m_collection.erase(m_collection.begin()+tableLimit, m_collection.end());
  }
}

std::ostream& operator<<(std::ostream &out, const TargetPhraseCollection &obj)
{
  TargetPhraseCollection::const_iterator iter;
  for (iter = obj.begin(); iter != obj.end(); ++iter) {
    const TargetPhrase &tp = **iter;
    out << tp << endl;
  }
  return out;
}


void TargetPhraseCollectionWithSourcePhrase::Add(TargetPhrase *targetPhrase)
{
  UTIL_THROW(util::Exception, "Must use method Add(TargetPhrase*, const Phrase&)");
}

void TargetPhraseCollectionWithSourcePhrase::Add(TargetPhrase *targetPhrase, const Phrase &sourcePhrase)
{
  m_collection.push_back(targetPhrase);
  m_sourcePhrases.push_back(sourcePhrase);
}

} // namespace