package ca.pfv.spmf.algorithms.sequentialpatterns.spm_fc_p.items;

import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

/**
 * Class to make possible the implementation of pseudoprojections already
 * explained in the paper of PrefixSpan Algorithm. By means of this class, we
 * convert a usual sequence in a pseudosequence, where we can point out the
 * different projection points that we have in every database projection.
 *
 * This class is inspired in SPMF PrefixSpan implementation.
 *
 * Copyright Antonio Gomariz Peñalver 2013
 *
 * This file is part of the SPMF DATA MINING SOFTWARE
 * (http://www.philippe-fournier-viger.com/spmf).
 *
 * SPMF 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.
 *
 * SPMF 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
 * SPMF. If not, see <http://www.gnu.org/licenses/>.
 *
 * @author agomariz
 */
public class PseudoSequenceDatabase {

    /**
     * The pseudosequences that compose the database
     */
    private List<PseudoSequence> pseudoSequences = new ArrayList<PseudoSequence>();

    /**
     * Get the list of pseudosequences from this database
     * @return the list of pseudosequences
     */
    public List<PseudoSequence> getPseudoSequences() {
        return pseudoSequences;
    }

    /**
     * It returns a string representation of this pseudo sequence database
     * @return the string representation
     */
    @Override
    public String toString() {
        StringBuilder sb = new StringBuilder("============  Pseudo-Sequence Database ==========");
        for (PseudoSequence sequence : pseudoSequences) {
            sb.append(sequence.getId());
            sb.append(":  ");
            sb.append(sequence.toString());
            sb.append('\n');
        }
        return sb.toString();
    }

    /**
     * It returns the number of pseudosequences that the database has
     * @return the number of pseudosequences
     */
    public int size() {
        return pseudoSequences.size();
    }

    /**
     * It returns the sequence IDs of pseudosequences in this database
     * @return a Set of sequence IDs.
     */
    public Set<Integer> getSequenceIDs() {
        Set<Integer> result = new HashSet<Integer>();
        for (PseudoSequence sequence : getPseudoSequences()) {
            result.add(sequence.getId());
        }
        return result;
    }

    /**
     * It adds a sequence to the database
     * @param newSequence the sequence to be added
     */
    public void addSequence(PseudoSequence newSequence) {
        pseudoSequences.add(newSequence);
    }

    /**
     * It clears the whole database
     */
    public void clear() {
        if (pseudoSequences != null) {
            pseudoSequences.clear();
            pseudoSequences = null;
        }
    }
}
