/*
    *  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. 
   *  
   */
  package org.apache.directory.server.ldap.handlers.request;
  
  
  import org.apache.directory.api.ldap.model.message.LdapResult;
  import org.apache.directory.api.ldap.model.message.ModifyDnRequest;
  import org.apache.directory.api.ldap.model.message.ModifyDnResponse;
  import org.apache.directory.api.ldap.model.message.ResultCodeEnum;
  import org.apache.directory.api.ldap.model.name.Dn;
  import org.apache.directory.api.ldap.model.schema.SchemaManager;
  import org.apache.directory.server.core.api.CoreSession;
  import org.apache.directory.server.ldap.LdapSession;
  import org.apache.directory.server.ldap.handlers.LdapRequestHandler;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  
  /**
   * A single reply MessageReceived handler for {@link org.apache.directory.api.ldap.model.message.ModifyDnRequest}s.
   *
   * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
   */
  public class ModifyDnRequestHandler extends LdapRequestHandler<ModifyDnRequest>
  {
      private static final Logger LOG = LoggerFactory.getLogger( ModifyDnRequestHandler.class );
  
  
      /**
       * Deal with a ModifyDN request received from a client.
       *
       * A ModifyDN operation has more than one semantic, depending on its parameters.
       *
       * In any case, the first argument is the Dn entry to be changed. We then
       * have the new relative Dn for this entry.
       *
       * Two other arguments can be provided :
       * - deleteOldRdn : if the old Rdn attributes should be removed from the
       * new entry or not (for instance, if the old Rdn was cn=acme, and the new
       * one is sn=acme, then we may have to remove the cn: acme from the attributes
       * list)
       * - newSuperior : this is a move operation. The entry is removed from its
       * current location, and created in the new one.
       */
      public void handle( LdapSession session, ModifyDnRequest modifyDnRequest )
      {
          ModifyDnResponse modifyDnResponse = ( ModifyDnResponse ) modifyDnRequest.getResultResponse(); 
          LdapResult result = modifyDnResponse.getLdapResult();
          LOG.debug( "Handling modify dn request while ignoring referrals: {}", modifyDnRequest );
  
          if ( modifyDnRequest.getName().isEmpty() )
          {
              // it is not allowed to modify the name of the Root DSE
              String msg = "Modify Dn is not allowed on Root DSE.";
              result.setResultCode( ResultCodeEnum.PROTOCOL_ERROR );
              result.setDiagnosticMessage( msg );
              session.getIoSession().write( modifyDnResponse );
              return;
          }
  
          try
          {
              SchemaManager schemaManager = session.getCoreSession().getDirectoryService().getSchemaManager();
              Dn newRdn = new Dn( schemaManager, modifyDnRequest.getNewRdn().getName() );
  
              Dn oldRdn = new Dn( schemaManager, modifyDnRequest.getName().getRdn().getName() );
  
              boolean rdnChanged = modifyDnRequest.getNewRdn() != null && !newRdn.equals( oldRdn );
  
              CoreSession coreSession = session.getCoreSession();
  
              if ( rdnChanged )
              {
                  if ( modifyDnRequest.getNewSuperior() != null )
                  {
                      coreSession.moveAndRename( modifyDnRequest );
                  }
                  else
                  {
                      coreSession.rename( modifyDnRequest );
                  }
              }
             else if ( modifyDnRequest.getNewSuperior() != null )
             {
                 modifyDnRequest.setNewRdn( null );
                 coreSession.move( modifyDnRequest );
             }
             else
             {
                 result.setDiagnosticMessage( "Attempt to move entry onto itself." );
                 result.setResultCode( ResultCodeEnum.ENTRY_ALREADY_EXISTS );
                 result.setMatchedDn( modifyDnRequest.getName() );
                 session.getIoSession().write( modifyDnResponse );
                 
                 return;
             }
 
             result.setResultCode( ResultCodeEnum.SUCCESS );
             session.getIoSession().write( modifyDnResponse );
         }
         catch ( Exception e )
         {
             handleException( session, modifyDnRequest, modifyDnResponse, e );
         }
     }
 }