/*
* This program is free software; you can redistribute it and/or modify it under the
* terms of the GNU Lesser General Public License, version 2.1 as published by the Free Software
* Foundation.
*
* You should have received a copy of the GNU Lesser General Public License along with this
* program; if not, you can obtain a copy at http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html
* or from the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* 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 Lesser General Public License for more details.
*
* Copyright (c) 2006 - 2013 Pentaho Corporation and Contributors.  All rights reserved.
*/

package org.pentaho.reporting.libraries.fonts.text;

/**
 * Creation-Date: 11.06.2006, 17:02:27
 *
 * @author Thomas Morgner
 */
public class GraphemeClusterProducer implements ClassificationProducer {
  private int lastClassification;
  private GraphemeClassifier classifier;

  public GraphemeClusterProducer() {
    classifier = GraphemeClassifier.getClassifier();
  }

  /**
   * Returns an alternating counter for the grapheme clusters. The value returned can be tested for equality; if two
   * subsequent calls return the same value, the characters of these calls belong to the same cluster.
   *
   * @param codePoint
   * @return true, if a new cluster starts, false if the old cluster continues.
   */
  public boolean createGraphemeCluster( final int codePoint ) {
    final int classification = classifier.getGraphemeClassification( codePoint );
    if ( classification == GraphemeClassifier.EXTEND ) {
      lastClassification = classification;
      return false;
    }

    if ( lastClassification == GraphemeClassifier.CR &&
      classification == GraphemeClassifier.LF ) {
      lastClassification = classification;
      return false;
    }

    if ( lastClassification == GraphemeClassifier.L ) {
      if ( ( classification & GraphemeClassifier.ANY_HANGUL_MASK ) ==
        GraphemeClassifier.ANY_HANGUL_MASK ) {
        lastClassification = classification;
        return false;
      }
    }

    final boolean oldLVorV =
      ( lastClassification & GraphemeClassifier.V_OR_LV_MASK ) ==
        GraphemeClassifier.V_OR_LV_MASK;
    final boolean newVorT =
      ( classification & GraphemeClassifier.V_OR_T_MASK ) ==
        GraphemeClassifier.V_OR_T_MASK;
    if ( oldLVorV && newVorT ) {
      lastClassification = classification;
      return false;
    }

    final boolean oldLVTorT =
      ( lastClassification & GraphemeClassifier.LVT_OR_T_MASK ) ==
        GraphemeClassifier.LVT_OR_T_MASK;
    if ( oldLVTorT && classification == GraphemeClassifier.T ) {
      lastClassification = classification;
      return false;
    }

    lastClassification = classification;
    return true;
  }

  public Object clone() throws CloneNotSupportedException {
    return super.clone();
  }

}