/***********************************************************************
 Moses - statistical machine translation system
 Copyright (C) 2006-2011 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 "RuleTableLoaderFactory.h"

#include "InputFileStream.h"
#include "RuleTableLoaderCompact.h"
#include "RuleTableLoaderStandard.h"
#include "UserMessage.h"
#include "Util.h"

#include <sstream>

namespace Moses
{

// Determines the rule table type by peeking inside the file then creates
// a suitable RuleTableLoader object.
std::auto_ptr<RuleTableLoader> RuleTableLoaderFactory::Create(
    const std::string &path)
{
  InputFileStream input(path);
  std::string line;
  std::getline(input, line);
  std::vector<std::string> tokens;
  Tokenize(tokens, line);
  if (tokens.size() == 1) {
    if (tokens[0] == "1") {
      return std::auto_ptr<RuleTableLoader>(new RuleTableLoaderCompact());
    }
    std::stringstream msg;
    msg << "Unsupported compact rule table format: " << tokens[0];
    UserMessage::Add(msg.str());
    return std::auto_ptr<RuleTableLoader>();
  }
  return std::auto_ptr<RuleTableLoader>(new RuleTableLoaderStandard());
}

}  // namespace Moses