/***********************************************************************
 Moses - statistical machine translation system
 Copyright (C) 2006-2012 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
 ***********************************************************************/

#pragma once

#include "IntermediateVarSpanNode.h"

#include <memory>
#include <vector>

namespace Moses
{

struct ApplicableRuleTrie;
struct VarSpanNode;

/** @todo what is this?
 */
class VarSpanTrieBuilder
{
public:
  std::auto_ptr<VarSpanNode> Build(ApplicableRuleTrie &);

private:
  typedef std::vector<IntermediateVarSpanNode> NodeVec;
  struct NodeVecState {
    std::size_t m_size;
    IntermediateVarSpanNode m_lastNode;
  };
  void Build(ApplicableRuleTrie &, NodeVec &, VarSpanNode &);
  void RecordState(const NodeVec &, NodeVecState &);
  void RestoreState(const NodeVecState &, NodeVec &);
};

}