#ifndef moses_PhraseLengthFeature_h
#define moses_PhraseLengthFeature_h

#include <stdexcept>
#include <string>
#include <map>

#include "StatelessFeatureFunction.h"
#include "moses/FF/FFState.h"
#include "moses/Word.h"
#include "moses/FactorCollection.h"

namespace Moses
{

/** Sets the features for length of source phrase, target phrase, both.
 */
class PhraseLengthFeature : public StatelessFeatureFunction
{
public:
  PhraseLengthFeature(const std::string &line);

  bool IsUseable(const FactorMask &mask) const {
    return true;
  }

  void EvaluateChart(const ChartBasedFeatureContext& context,
                     ScoreComponentCollection*) const {
    throw std::logic_error("PhraseLengthFeature not valid in chart decoder");
  }

  virtual void Evaluate(const Phrase &source
                        , const TargetPhrase &targetPhrase
                        , ScoreComponentCollection &scoreBreakdown
                        , ScoreComponentCollection &estimatedFutureScore) const;

};

}

#endif // moses_PhraseLengthFeature_h