/*
    *   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.api.ldap.extras.extended.ads_impl.whoAmI;
  
  
  import java.io.PrintWriter;
  import java.io.StringWriter;
  import java.nio.ByteBuffer;
  
  import org.apache.directory.api.asn1.DecoderException;
  import org.apache.directory.api.asn1.ber.Asn1Decoder;
  import org.apache.directory.api.ldap.codec.api.ExtendedOperationFactory;
  import org.apache.directory.api.ldap.codec.api.ExtendedResponseDecorator;
  import org.apache.directory.api.ldap.codec.api.LdapApiService;
  import org.apache.directory.api.ldap.extras.extended.whoAmI.WhoAmIRequest;
  import org.apache.directory.api.ldap.extras.extended.whoAmI.WhoAmIRequestImpl;
  import org.apache.directory.api.ldap.extras.extended.whoAmI.WhoAmIResponse;
  import org.apache.directory.api.ldap.extras.extended.whoAmI.WhoAmIResponseImpl;
  import org.apache.directory.api.ldap.model.message.ExtendedRequest;
  import org.apache.directory.api.ldap.model.message.ExtendedResponse;
  import org.apache.directory.api.ldap.model.message.ResultCodeEnum;
  
  
  /**
   * An {@link ExtendedOperationFactory} for creating WhoAmI extended request response 
   * pairs.
   *
   * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
   */
  public class WhoAmIFactory implements ExtendedOperationFactory
  {
      private LdapApiService codec;
  
  
      /**
       * Creates a new instance of WhoAmIFactory.
       *
       * @param codec The codec for this factory.
       */
      public WhoAmIFactory( LdapApiService codec )
      {
          this.codec = codec;
      }
  
  
      /**
       * {@inheritDoc}
       */
      @Override
      public String getOid()
      {
          return WhoAmIRequest.EXTENSION_OID;
      }
  
  
      /**
       * {@inheritDoc}
       */
      @Override
      public WhoAmIResponse newResponse( byte[] encodedValue ) throws DecoderException
      {
          WhoAmIResponseDecorator response = new WhoAmIResponseDecorator( codec,
              new WhoAmIResponseImpl() );
          response.setResponseValue( encodedValue );
          return response;
      }
  
  
      /**
       * {@inheritDoc}
       */
      @Override
      public WhoAmIRequest newRequest( byte[] value )
      {
          WhoAmIRequestDecorator req = new WhoAmIRequestDecorator( codec, new WhoAmIRequestImpl() );
  
          if ( value != null )
          {
              req.setRequestValue( value );
          }
  
          return req;
     }
 
 
     /**
      * {@inheritDoc}
      */
     @Override
     public WhoAmIRequestDecorator decorate( ExtendedRequest modelRequest )
     {
         if ( modelRequest instanceof WhoAmIRequestDecorator )
         {
             return ( WhoAmIRequestDecorator ) modelRequest;
         }
 
         return new WhoAmIRequestDecorator( codec, ( WhoAmIRequest ) modelRequest );
     }
 
 
     /**
      * {@inheritDoc}
      */
     @Override
     public WhoAmIResponseDecorator decorate( ExtendedResponse decoratedResponse )
     {
         if ( decoratedResponse instanceof WhoAmIResponseDecorator )
         {
             return ( WhoAmIResponseDecorator ) decoratedResponse;
         }
 
         if ( decoratedResponse instanceof WhoAmIResponse )
         {
             return new WhoAmIResponseDecorator( codec, ( WhoAmIResponse ) decoratedResponse );
         }
 
         // It's an opaque extended operation
         @SuppressWarnings("unchecked")
         ExtendedResponseDecorator<ExtendedResponse> response = ( ExtendedResponseDecorator<ExtendedResponse> ) decoratedResponse;
 
         // Decode the response, as it's an opaque operation
         Asn1Decoder decoder = new Asn1Decoder();
 
         byte[] value = response.getResponseValue();
         ByteBuffer buffer = ByteBuffer.wrap( value );
 
         WhoAmIResponseContainer container = new WhoAmIResponseContainer();
         WhoAmIResponse whoAmIResponse = null;
 
         try
         {
             decoder.decode( buffer, container );
 
             whoAmIResponse = container.getWhoAmIResponse();
 
             // Now, update the created response with what we got from the extendedResponse
             whoAmIResponse.getLdapResult().setResultCode( response.getLdapResult().getResultCode() );
             whoAmIResponse.getLdapResult().setDiagnosticMessage( response.getLdapResult().getDiagnosticMessage() );
             whoAmIResponse.getLdapResult().setMatchedDn( response.getLdapResult().getMatchedDn() );
             whoAmIResponse.getLdapResult().setReferral( response.getLdapResult().getReferral() );
         }
         catch ( DecoderException de )
         {
             StringWriter sw = new StringWriter();
             de.printStackTrace( new PrintWriter( sw ) );
             String stackTrace = sw.toString();
 
             // Error while decoding the value. 
             whoAmIResponse = new WhoAmIResponseImpl(
                 decoratedResponse.getMessageId(),
                 ResultCodeEnum.OPERATIONS_ERROR,
                 stackTrace );
         }
 
         return new WhoAmIResponseDecorator( codec, whoAmIResponse );
     }
 }