/*
  $Id: Metrics.h 15565 2013-01-07 14:27:05Z sloot $
  $URL: https://ilk.uvt.nl/svn/trunk/sources/Timbl6/include/timbl/Metrics.h $

  Copyright (c) 1998 - 2013
  ILK   - Tilburg University
  CLiPS - University of Antwerp
 
  This file is part of timbl

  timbl 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.

  timbl 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 this program; if not, see <http://www.gnu.org/licenses/>.

  For questions and suggestions, see:
      http://ilk.uvt.nl/software.html
  or send mail to:
      timbl@uvt.nl
*/

#ifndef TIMBL_METRICS_H
#define TIMBL_METRICS_H

#include <limits> 

namespace Timbl{

  extern const double maxSimilarity;
  
  metricClass *getMetricClass( MetricType );

  class metricClass {
  public:
  metricClass( MetricType m ): _type(m){};
    virtual ~metricClass() {};
    MetricType type() const { return _type; };
    virtual bool isSimilarityMetric() const = 0;
    virtual bool isNumerical() const = 0;
    virtual bool isStorable() const = 0;
    virtual double distance( FeatureValue *, FeatureValue *, 
			     size_t=1, double = 1.0 ) const = 0;
  private:
    MetricType _type;
  };

  class distanceMetricClass: public metricClass {
  public:
  distanceMetricClass( MetricType m ): metricClass(m){};
    virtual ~distanceMetricClass() {};
    bool isSimilarityMetric() const { return false; };
  };

  class OverlapMetric: public distanceMetricClass {
  public:
  OverlapMetric(): distanceMetricClass( Overlap ){};
    bool isNumerical() const { return false; };
    bool isStorable() const { return false; };
    double distance( FeatureValue *, FeatureValue *, size_t, double ) const;
  };
  
  class NumericMetricClass: public distanceMetricClass {
  public:
  NumericMetricClass( MetricType m ): distanceMetricClass( m ){};
    virtual ~NumericMetricClass() {};
    bool isNumerical() const { return true; };
    bool isStorable() const { return false; };
  };

  class NumericMetric: public NumericMetricClass {
  public:
  NumericMetric(): NumericMetricClass( Numeric ){};
    double distance( FeatureValue *, FeatureValue *, size_t, double ) const;
  };

  class EuclideanMetric: public NumericMetricClass {
  public:
  EuclideanMetric(): NumericMetricClass( Euclidean ){};
    double distance( FeatureValue *, FeatureValue *, size_t, double ) const;
  };

  class ValueDiffMetric: public distanceMetricClass {
  public:
  ValueDiffMetric(): distanceMetricClass( ValueDiff ){};
    bool isNumerical() const { return false; };
    bool isStorable() const { return true; };
    double distance( FeatureValue *, FeatureValue *, size_t, double ) const;
  };
  
  class DiceMetric: public distanceMetricClass {
  public:
  DiceMetric(): distanceMetricClass( Dice ){};
    bool isNumerical() const { return false; };
    bool isStorable() const { return true; };
    double distance( FeatureValue *, FeatureValue *, size_t, double ) const;
  };

  class JeffreyMetric: public distanceMetricClass {
  public:
  JeffreyMetric(): distanceMetricClass( JeffreyDiv ){};
    bool isNumerical() const { return false; };
    bool isStorable() const { return true; };
    double distance( FeatureValue *, FeatureValue *, size_t, double ) const;
  };

  class JSMetric: public distanceMetricClass {
  public:
  JSMetric(): distanceMetricClass( JSDiv ){};
    bool isNumerical() const { return false; };
    bool isStorable() const { return true; };
    double distance( FeatureValue *, FeatureValue *, size_t, double ) const;
  };

  class LevenshteinMetric: public distanceMetricClass {
  public:
  LevenshteinMetric(): distanceMetricClass( Levenshtein ){};
    bool isNumerical() const { return false; };
    bool isStorable() const { return true; };
    double distance( FeatureValue *, FeatureValue *, size_t, double ) const;
  };

  class similarityMetricClass: public metricClass {
  public:
  similarityMetricClass( MetricType m ): metricClass( m ){};
    virtual ~similarityMetricClass() {};
    bool isSimilarityMetric() const { return true; };
    bool isNumerical() const { return true; };
    bool isStorable() const { return false; };
  };

  class CosineMetric: public similarityMetricClass {
  public:
  CosineMetric(): similarityMetricClass( Cosine ){};
    double distance( FeatureValue *, FeatureValue *, size_t, double ) const;
  };

  class DotProductMetric: public similarityMetricClass {
  public:
  DotProductMetric(): similarityMetricClass( DotProduct ){};
    double distance( FeatureValue *, FeatureValue *, size_t, double ) const;
  };

}  

#endif // TIMBL_METRICS_H