/**
 * Copyright (C) 2009 eXo Platform SAS.
 * 
 * This 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 software 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 software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */

package org.exoplatform.services.token;


import org.exoplatform.services.chars.CharsUtil;
import org.exoplatform.services.chars.SpecChar;
import org.exoplatform.services.common.util.Queue;

/**
 *  Author : Nhu Dinh Thuan
 *          Email:nhudinhthuan@yahoo.com
 * Aug 5, 2006
 */
public class TokenParser
{

   public static abstract class Factory<T> extends Queue<T>
   {

      public abstract int create(char[] data, int start, int end, int type);

   }

   private static char[] closeComment = {SpecChar.HYPHEN, SpecChar.HYPHEN, SpecChar.CLOSE_TAG};

   public synchronized <T, E extends Factory<T>> void createBeans(Factory<T> factory, char[] data) throws Exception
   {
      if (data == null || data.length < 2)
         return;
      int start = 1;
      int end = 0;
      boolean open = false;
      while (end < data.length)
      {
         if (data[end] == SpecChar.OPEN_TAG && !open)
         {
            start = factory.create(data, start, end, TypeToken.CONTENT) + 1;
            open = true;
         }
         else if (data[end] == SpecChar.OPEN_TAG && open)
         {
            if (Character.isWhitespace(data[start]))
            {
               start = factory.create(data, start - 1, end, TypeToken.CONTENT) + 1;
            }
            else
            {
               start = factory.create(data, start, end, TypeToken.TAG) + 1;
            }
            open = true;
         }
         else if (data[end] == SpecChar.CLOSE_TAG && open)
         {
            start = factory.create(data, start, end, TypeToken.TAG) + 1;
            if (end < (start - 1))
               end = start - 1;
            open = false;
         }
         else if (data[end] == SpecChar.PUNCTUATION_MASK)
         {
            if (isComment(data, end))
            {
               start = end;
               end = findEndComment(data, end);
               start = factory.create(data, start - 1, end, TypeToken.COMMENT);
               if (start < data.length && data[start] == SpecChar.OPEN_TAG)
                  start++;
               open = false;
               continue;
            }
         }
         end++;
      }
      if (start < end)
         factory.create(data, start, end, TypeToken.CONTENT);
   }

   public boolean isComment(char[] value, int start)
   {
      if (start < 1)
         return false;
      if (value[start - 1] != SpecChar.OPEN_TAG)
         return false;
      return value[start + 1] == SpecChar.HYPHEN && value[start + 2] == SpecChar.HYPHEN;
   }

   public int findEndComment(char[] value, int start)
   {
      int index = -1;
      index = CharsUtil.indexOf(value, closeComment, start);
      if (index > -1)
         return index + 3;
      index = CharsUtil.indexOf(value, SpecChar.n, start);
      if (index > -1)
         return index + 1;
      return value.length;
   }

}
