/*
 * JBoss, Home of Professional Open Source
 * Copyright 2005, JBoss Inc., and individual contributors as indicated
 * by the @authors tag. See the copyright.txt in the distribution for a
 * full listing of individual contributors.
 *
 * 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.jboss.ejb.plugins.cmp.jdbc;

import java.util.Map;
import java.util.HashMap;


/**
 * This class manages aliases for generated queries.
 *
 * @author <a href="mailto:dain@daingroup.com">Dain Sundstrom</a>
 * @version $Revision: 1.1.4.4 $
 */
final class AliasManager
{
   private static final String RELATION_TABLE_SUFFIX = "_RELATION_TABLE";

   private final String prefix;
   private final String suffix;
   private final int maxLength;
   private final Map aliases = new HashMap();
   private final Map relationTableAliases = new HashMap();

   private int count = 0;

   public AliasManager(String prefix, String suffix, int maxLength)
   {
      this.prefix = prefix;
      this.suffix = suffix;
      this.maxLength = maxLength;
   }

   public String getAlias(String path)
   {
      String alias = (String)aliases.get(path);
      if(alias == null)
      {
         alias = createAlias(path);
         aliases.put(path, alias);
      }
      return alias;
   }

   private String createAlias(String path)
   {
      StringBuffer alias = new StringBuffer();
      alias.append(prefix).append(count++).append(suffix);
      alias.append(path.replace('.', '_'));

      return alias.substring(0, Math.min(maxLength, alias.length()));
   }

   public void addAlias(String path, String alias)
   {
      aliases.put(path, alias);
   }

   public String getRelationTableAlias(String path)
   {
      String relationTableAlias = (String)relationTableAliases.get(path);
      if(relationTableAlias == null)
      {
         relationTableAlias = createRelationTableAlias(path);
         relationTableAliases.put(path, relationTableAlias);
      }
      return relationTableAlias;
   }

   private String createRelationTableAlias(String path)
   {
      StringBuffer relationTableAlias = new StringBuffer();

      relationTableAlias.append(prefix).append(count++).append(suffix);

      relationTableAlias.append(path.replace('.', '_'));
      relationTableAlias.append(RELATION_TABLE_SUFFIX);

      return relationTableAlias.substring(
         0, Math.min(maxLength, relationTableAlias.length()));
   }
}
