content: package org.apache.lucene.analysis.hu;
  
  /**
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You under the Apache License, Version 2.0
   * (the "License"); you may not use this file except in compliance with
   * the License.  You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  /* 
   * This algorithm is updated based on code located at:
   * http://members.unine.ch/jacques.savoy/clef/
   * 
   * Full copyright for that code follows:
   */
  
  /*
   * Copyright (c) 2005, Jacques Savoy
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without 
   * modification, are permitted provided that the following conditions are met:
   *
   * Redistributions of source code must retain the above copyright notice, this 
   * list of conditions and the following disclaimer. Redistributions in binary 
   * form must reproduce the above copyright notice, this list of conditions and
   * the following disclaimer in the documentation and/or other materials 
   * provided with the distribution. Neither the name of the author nor the names 
   * of its contributors may be used to endorse or promote products derived from 
   * this software without specific prior written permission.
   * 
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 
   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   * POSSIBILITY OF SUCH DAMAGE.
   */
  
  import static org.apache.lucene.analysis.util.StemmerUtil.*;
  
  /**
   * Light Stemmer for Hungarian.
   * <p>
   * This stemmer implements the "UniNE" algorithm in:
   * <i>Light Stemming Approaches for the French, Portuguese, German and Hungarian Languages</i>
   * Jacques Savoy
   */
  public class HungarianLightStemmer {
    public int stem(char s[], int len) {
      for (int i = 0; i < len; i++)
        switch(s[i]) {
          case 'á': s[i] = 'a'; break;
          case 'ë':
          case 'é': s[i] = 'e'; break;
          case 'í': s[i] = 'i'; break;
          case 'ó':
          case 'ő':
          case 'õ':
          case 'ö': s[i] = 'o'; break;
          case 'ú':
          case 'ű':
          case 'ũ':
          case 'û':
          case 'ü': s[i] = 'u'; break;
        }
      
      len = removeCase(s, len);
      len = removePossessive(s, len);
      len = removePlural(s, len);
      return normalize(s, len);
    }
    
    private int removeCase(char s[], int len) {
      if (len > 6 && endsWith(s, len, "kent"))
        return len - 4;
      
      if (len > 5) {
        if (endsWith(s, len, "nak") ||
            endsWith(s, len, "nek") ||
            endsWith(s, len, "val") ||
            endsWith(s, len, "vel") ||
            endsWith(s, len, "ert") ||
            endsWith(s, len, "rol") ||
            endsWith(s, len, "ban") ||
            endsWith(s, len, "ben") ||
            endsWith(s, len, "bol") ||
            endsWith(s, len, "nal") ||
            endsWith(s, len, "nel") ||
            endsWith(s, len, "hoz") ||
            endsWith(s, len, "hez") ||
            endsWith(s, len, "tol"))
          return len - 3;
        
        if (endsWith(s, len, "al") || endsWith(s, len, "el")) {
          if (!isVowel(s[len-3]) && s[len-3] == s[len-4])
            return len - 3;
        }
      }
      
      if (len > 4) {
        if (endsWith(s, len, "at") ||
            endsWith(s, len, "et") ||
            endsWith(s, len, "ot") ||
            endsWith(s, len, "va") ||
            endsWith(s, len, "ve") ||
            endsWith(s, len, "ra") ||
            endsWith(s, len, "re") ||
            endsWith(s, len, "ba") ||
            endsWith(s, len, "be") ||
            endsWith(s, len, "ul") ||
            endsWith(s, len, "ig"))
          return len - 2;
        
        if ((endsWith(s, len, "on") || endsWith(s, len, "en")) && !isVowel(s[len-3]))
            return len - 2;
        
        switch(s[len-1]) {
          case 't':
          case 'n': return len - 1;
          case 'a':
          case 'e': if (s[len-2] == s[len-3] && !isVowel(s[len-2])) return len - 2;
        }
      }
      
      return len;
    }
  
    private int removePossessive(char s[], int len) {
      if (len > 6) {
        if (!isVowel(s[len-5]) && 
           (endsWith(s, len, "atok") || 
            endsWith(s, len, "otok") || 
            endsWith(s, len, "etek")))
          return len - 4;
        
        if (endsWith(s, len, "itek") || endsWith(s, len, "itok"))
          return len - 4;
      }
      
      if (len > 5) {
        if (!isVowel(s[len-4]) &&
          (endsWith(s, len, "unk") ||
           endsWith(s, len, "tok") ||
           endsWith(s, len, "tek")))
          return len - 3;
        
        if (isVowel(s[len-4]) && endsWith(s, len, "juk"))
          return len - 3;
        
        if (endsWith(s, len, "ink"))
          return len - 3;
      }
      
      if (len > 4) {
        if (!isVowel(s[len-3]) &&
           (endsWith(s, len, "am") ||
            endsWith(s, len, "em") ||
            endsWith(s, len, "om") ||
            endsWith(s, len, "ad") ||
            endsWith(s, len, "ed") ||
            endsWith(s, len, "od") ||
            endsWith(s, len, "uk")))
          return len - 2;
        
        if (isVowel(s[len-3]) &&
           (endsWith(s, len, "nk") ||
            endsWith(s, len, "ja") ||
            endsWith(s, len, "je")))
          return len - 2;
        
        if (endsWith(s, len, "im") ||
            endsWith(s, len, "id") ||
            endsWith(s, len, "ik"))
          return len - 2;
      }
      
      if (len > 3)
        switch(s[len-1]) {
          case 'a':
          case 'e': if (!isVowel(s[len-2])) return len - 1; break;
          case 'm':
          case 'd': if (isVowel(s[len-2])) return len - 1; break;
          case 'i': return len - 1;
        }
      
      return len;
    }
  
    @SuppressWarnings("fallthrough")
    private int removePlural(char s[], int len) {
      if (len > 3 && s[len-1] == 'k')
        switch(s[len-2]) {
          case 'a':
          case 'o':
          case 'e': if (len > 4) return len - 2; /* intentional fallthru */
          default: return len - 1;
        }
      return len;
    }
  
    private int normalize(char s[], int len) {
      if (len > 3)
        switch(s[len-1]) {
          case 'a':
          case 'e':
          case 'i':
          case 'o': return len - 1;
        }
      return len;
    }
  
    private boolean isVowel(char ch) {
      switch(ch) {
        case 'a':
        case 'e':
        case 'i':
        case 'o':
        case 'u':
        case 'y': return true;
        default: return false;
      }
    }
  }
  