package org.activityinfo.core.shared.importing.strategy;
/*
 * #%L
 * ActivityInfo Server
 * %%
 * Copyright (C) 2009 - 2013 UNICEF
 * %%
 * This program 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.
 * 
 * This program 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/gpl-3.0.html>.
 * #L%
 */

import org.activityinfo.core.shared.importing.match.names.LatinPlaceNameScorer;
import org.activityinfo.core.shared.importing.source.SourceRow;

/**
 * @author yuriyz on 5/19/14.
 */
public class InstanceScorer {

    public static class Score {
        private final double bestScore;
        private final double[] bestScores;
        private final int bestMatchIndex;
        private final String[] imported;

        public Score(double bestScore, double[] bestScores, int bestMatchIndex, String[] imported) {
            this.bestScore = bestScore;
            this.bestScores = bestScores;
            this.bestMatchIndex = bestMatchIndex;
            this.imported = imported;
        }

        public double getBestScore() {
            return bestScore;
        }

        public double[] getBestScores() {
            return bestScores;
        }

        public int getBestMatchIndex() {
            return bestMatchIndex;
        }

        public String[] getImported() {
            return imported;
        }
    }

    public static final double MINIMUM_SCORE = 0.25;

    private final InstanceScoreSource source;
    private final LatinPlaceNameScorer scorer = new LatinPlaceNameScorer();

    public InstanceScorer(InstanceScoreSource source) {
        this.source = source;
    }

    public Score score(SourceRow row) {
        double bestScore = 0;
        double bestScores[] = new double[source.getSources().size()];
        int bestMatchIndex = -1;

        String[] imported = toArray(row);

        if (imported != null) {
            for (int i = 0; i != source.getReferenceInstanceIds().size(); ++i) {
                double[] score = scorePotentialMatch(imported, source.getReferenceValues().get(i));
                if (score != null) {
                    double total = sum(score);
                    if (total > bestScore) {
                        bestMatchIndex = i;
                        bestScore = total;
                        bestScores = score;
                    }
                }
            }
        }
//        if (bestMatchIndex != -1) {
//            System.out.println("Score: " + Arrays.toString(bestScores) + "  " +
//                    Arrays.toString(source.getReferenceValues().get(bestMatchIndex)));
//        }
        return new Score(bestScore, bestScores, bestMatchIndex, imported);
    }

    private double sum(double[] score) {
        double sum = 0;
        for (int i = 0; i != score.length; ++i) {
            sum += score[i];
        }
        return sum;
    }

    private double[] scorePotentialMatch(String[] imported, String[] reference) {
        double scores[] = new double[imported.length];
        double max = 0;
        for (int i = 0; i != imported.length; ++i) {
            if (imported[i] != null && reference[i] != null) {
                scores[i] = scorer.score(imported[i], reference[i]);
                max = Math.max(scores[i], max);
            }
        }
        if (max > MINIMUM_SCORE) {
            return scores;
        } else {
            return null;
        }
    }

    private String[] toArray(SourceRow row) {
        String[] values = new String[source.getSources().size()];
        for (int i = 0; i != source.getSources().size(); ++i) {
            if (!source.getSources().get(i).isMissing(row)) {
                values[i] = source.getSources().get(i).getValue(row);
            }
        }
        return values;
    }

}