package de.lmu.ifi.dbs.elki.datasource.filter;

/*
 This file is part of ELKI:
 Environment for Developing KDD-Applications Supported by Index-Structures

 Copyright (C) 2012
 Ludwig-Maximilians-Universität München
 Lehr- und Forschungseinheit für Datenbanksysteme
 ELKI Development Team

 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU Affero 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 Affero General Public License for more details.

 You should have received a copy of the GNU Affero General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

import java.util.ArrayList;

import de.lmu.ifi.dbs.elki.datasource.bundle.MultipleObjectsBundle;
import de.lmu.ifi.dbs.elki.logging.Logging;
import de.lmu.ifi.dbs.elki.utilities.optionhandling.AbstractParameterizer;

/**
 * A filter to remove entries that have missing values.
 * 
 * @author Erich Schubert
 */
public class NoMissingValuesFilter implements ObjectFilter {
  /**
   * Class logger
   */
  private static final Logging logger = Logging.getLogger(NoMissingValuesFilter.class);

  /**
   * Constructor.
   */
  public NoMissingValuesFilter() {
    super();
  }

  @Override
  public MultipleObjectsBundle filter(final MultipleObjectsBundle objects) {
    if(logger.isDebugging()) {
      logger.debug("Filtering the data set");
    }

    MultipleObjectsBundle bundle = new MultipleObjectsBundle();
    for(int j = 0; j < objects.metaLength(); j++) {
      bundle.appendColumn(objects.meta(j), new ArrayList<Object>());
    }
    for(int i = 0; i < objects.dataLength(); i++) {
      boolean good = true;
      for(int j = 0; j < objects.metaLength(); j++) {
        if(objects.data(i, j) == null) {
          good = false;
          break;
        }
      }
      if(good) {
        bundle.appendSimple(objects.getRow(i));
      }
    }
    return bundle;
  }

  /**
   * Parameterization class.
   * 
   * @author Erich Schubert
   * 
   * @apiviz.exclude
   */
  public static class Parameterizer extends AbstractParameterizer {
    @Override
    protected Object makeInstance() {
      return new NoMissingValuesFilter();
    }
  }
}