////////////////////////////////////////////////////////////////////////////////
   //CabaWeb
   //Copyright (C) 2004  Thomas Vogt <Thomas.Vogt@TVC-Software.com>
   //
   //This library is free software; you can redistribute it and/or
   //modify it under the terms of the GNU Lesser General Public
   //License as published by the Free Software Foundation; either
   //version 2.1 of the License, or (at your option) any later version.
   //
  //This library 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.
  //
  //You should have received a copy of the GNU Lesser General Public
  //License along with this library; if not, write to the Free Software
  //Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  ////////////////////////////////////////////////////////////////////////////////
  
  package org.fhw.cabaweb.tools;
  
  import java.io.IOException;
  import java.io.UnsupportedEncodingException;
  import java.net.URLDecoder;
  import java.net.URLEncoder;
  import java.util.Properties;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.fhw.cabaweb.calculation.threads.Lock;
  
  /***
   * Klasse um verschiedene mit Strings zusammenh&auml;ngende Funktionen zusammenzufassen
   *
   * @author  <a href="mailto:thomas.vogt@tvc-software.com">Thomas Vogt</a>
   * @version Version 1.0 06.07.2004
   */
  public final class StringUtilities
  {
      /*** Commons Logging Instanz */
      private static Log log = LogFactory.getLog("org.fhw.cabaweb.tools.StringUtilities");
  
      /***
       * Standardkonstruktor der nicht zug&auml;nglich sein soll, da dies eine Utility Klasse ist
       */
      protected StringUtilities()
      {
          throw new UnsupportedOperationException(); // Aufrufe aus eventuellen SubKlassen verhindern
      }
  
      /***
       * Gibt true zur&uuml;ck wenn es sich um eine g&uuuml;ltige eMail Adresse handelt
       * (Bedingung mindestens ein "@" Zeichen und ein Punkt nach dem "@" in der eMail Adresse.
       *
       * @param   emailAddress String mit der zu pr&uuml;fenden eMail Adresse
       * @return  true wenn korrekt und false wenn nicht
       */
      public static final boolean isValidEmailAddress(String emailAddress)
      {
          emailAddress = emailAddress.trim();
  
          boolean isValid = false;
  
          if (emailAddress != null && emailAddress.length() > 3 && emailAddress.indexOf("@") != -1 && emailAddress.indexOf(".") != -1 && emailAddress.indexOf("@") < emailAddress.lastIndexOf(".") && emailAddress.indexOf("@") > 0 && emailAddress.indexOf("@") == emailAddress.lastIndexOf("@") && emailAddress.lastIndexOf(".") + 2 <= emailAddress.length())
          {
              isValid = true;
          }
  
          return isValid;
      }
  
      /***
       * Konvertiert den in UTF-8 codierten String in ISO-8859-1 um.
       *
       * @param   utf8string In UTF-8 codierter String
       * @return  Der ISO-8859-1 String
       */
      public static final String convertUTF8String(String utf8string)
      {
          Properties properties = StringUtilities.getPropertiesFromFile("cabaweb.properties");
  
          String convert = properties.getProperty("ConvertUTF8");
  
          String from = null;
          String to = utf8string;
  
          if(convert.compareTo("true") == 0 || convert.compareTo("on") == 0 || convert.compareTo("yes") == 0)
          {
              try
              {
  
                  from = URLEncoder.encode(utf8string);
                  to = URLDecoder.decode(from, "UTF8");
              }
              catch (UnsupportedEncodingException e)
              {
                  log.error(e.getMessage(), e);
              }
          }
         
         return to;
     }
 
     /***
      * Formatiert den gegebenen String so um, dass die hier geprüften Zeichen
      * als HTML Code Zeichen ausgegeben werden.
      *
      * @param   eingabe Der umzuwandelnde String
      * @return  Der konvertierte String
      */
     public static final String toHTMLString(String eingabe)
     {
         StringBuffer out = new StringBuffer();
         char[] eingabechars = eingabe.toCharArray();
 
         for (int i = 0; i < eingabechars.length; i++)
         {
             char c = eingabechars[i];
 
             if (c == '\'')
             {
                 out.append("&#39;");
             }
             else if (c == '\"')
             {
                 out.append("&quot;");
             }
             else if (c == '&')
             {
                 out.append("&amp;");
             }
             else if (c == 'ä')
             {
                 out.append("&auml;");
             }
             else if (c == 'ö')
             {
                 out.append("&ouml;");
             }
             else if (c == 'ü')
             {
                 out.append("&uuml;");
             }
             else if (c == 'Ä')
             {
                 out.append("&Auml;");
             }
             else if (c == 'Ö')
             {
                 out.append("&Ouml;");
             }
             else if (c == 'Ü')
             {
                 out.append("&Uuml;");
             }
             else if (c == '<')
             {
                 out.append("&lt;");
             }
             else if (c == '>')
             {
                 out.append("&gt;");
             }
             else if (c == 'ß')
             {
                 out.append("&szlig;");
             }
             else if (c == '€')
             {
                 out.append("&#8364;");
             }
             else if (c == '\n')
             {
                 out.append("<BR/>\n");
             }
             else
             {
                 out.append(c);
             }
         }
 
         return out.toString();
     }
 
     public final static Properties getPropertiesFromFile(String propertiesFile)
     {
         Properties properties = new Properties();
         Lock lock = new Lock();
 
         try
         {
             properties.load(lock.getClass().getClassLoader().getResourceAsStream(propertiesFile));
         }
         catch (IOException e)
         {
             log.error(e.getLocalizedMessage(), e);
         }
 
         return properties;
     }
 }