// ////////////////////////////////////////////////////////////////////////////
   // dexterIM - Instant Messaging Framework
   // Copyright (C) 2003 Christoph Walcher
   //
   // 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 2 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, write to the Free Software
  // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  //////////////////////////////////////////////////////////////////////////////
  package net.sf.dexterim.msn.util;
  
  import java.io.FileInputStream;
  import java.io.FileNotFoundException;
  import java.io.IOException;
  import java.util.ArrayList;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Properties;
  
  /***
   * Description of the Class
   * 
   * @author christoph
   */
  public class SpecialCharacters {
    private static SpecialCharacters instance;
  
    private List encodedChars;
    private List decodedChars;
  
    /***
     * Creates a new instance of SpecialCharacters
     */
    protected SpecialCharacters() {
      encodedChars = new ArrayList();
      decodedChars = new ArrayList();
  
      initialize(encodedChars, decodedChars);
    }
  
    protected final void initialize(List encodedChars, List decodedChars) {
      Properties props = new Properties();
  
      try {
        props.load(
          new FileInputStream(
            getClass().getResource("characters.properties").getFile()));
  
        Iterator propertyIter = props.keySet().iterator();
  
        while (propertyIter.hasNext()) {
          String decodeChar = (String)propertyIter.next();
          String encodeChar = (String)props.get(decodeChar);
  
          decodedChars.add(decodeChar);
          encodedChars.add(encodeChar);
        }
      } catch (FileNotFoundException e) {
        e.printStackTrace();
      } catch (IOException e) {
        e.printStackTrace();
      }
    }
    /***
     * Gets the instance attribute of the SpecialCharacters class
     * 
     * @return The instance value
     */
    public static synchronized SpecialCharacters getInstance() {
      if (instance == null) {
        instance = new SpecialCharacters();
      }
  
      return instance;
    }
  
    /***
     * Description of the Method
     * 
     * @param str
     *            Description of the Parameter
     * @return Description of the Return Value
     */
    public String decode(String str) {
      return decode(str, false);
    }
  
    /***
     * Description of the Method
     * 
    * @param str
    *            Description of the Parameter
    * @param urldecode
    *            Description of the Parameter
    * @return Description of the Return Value
    */
   public String decode(String str, boolean urldecode) {
 
     String decodedString;
 
     if (urldecode) {
       decodedString = urlDecode(str);
     } else {
       decodedString = str;
     }
 
     for (int i = 0; i < decodedChars.size(); i++) {
       decodedString =
         replace(decodedString, getDecodedChar(i), getEncodedChar(i));
     }
 
     return decodedString;
   }
 
   private String urlDecode(String str) {
     try {
       return java.net.URLDecoder.decode(str, "UTF-8");
     } catch (java.io.UnsupportedEncodingException ex) {
       ex.printStackTrace();
     }
 
     return str;
   }
 
   /***
    * Description of the Method
    * 
    * @param str
    *            Description of the Parameter
    * @return Description of the Return Value
    */
   public String encode(String str) {
     return encode(str, false);
   }
 
   /***
    * Description of the Method
    * 
    * @param str
    *            Description of the Parameter
    * @param urlencode
    *            Description of the Parameter
    * @return Description of the Return Value
    */
   public String encode(String str, boolean urlencode) {
     String encodedString;
 
     if (urlencode) {
       encodedString = urlEncode(str);
     } else {
       encodedString = str;
     }
 
     for (int i = 0; i < decodedChars.size(); i++) {
       encodedString =
         replace(encodedString, getEncodedChar(i), getDecodedChar(i));
     }
 
     return encodedString;
   }
 
   private String urlEncode(String string) {
     try {
       return java.net.URLEncoder.encode(string, "UTF-8");
     } catch (java.io.UnsupportedEncodingException ex) {
       ex.printStackTrace();
     }
 
     return string;
   }
 
   protected String getEncodedChar(int index) {
     return (String)decodedChars.get(index);
   }
 
   protected String getDecodedChar(int index) {
     return (String)encodedChars.get(index);
   }
 
   /***
    * Description of the Method
    * 
    * @param str
    *            Description of the Parameter
    * @param a
    *            Description of the Parameter
    * @param b
    *            Description of the Parameter
    * @return Description of the Return Value
    */
   public String replace(String string, String a, String b) {
     int i = 0;
 
     String returnValue = string;
 
     while ((i = returnValue.indexOf(a)) != -1) {
       returnValue =
         returnValue.substring(0, i) + b + returnValue.substring(i + a.length());
     }
 
     return returnValue;
   }
 }