/*
    *  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.codec.controls.search.subentries;
  
  
  import java.nio.ByteBuffer;
  
  import org.apache.directory.api.asn1.Asn1Object;
  import org.apache.directory.api.asn1.DecoderException;
  import org.apache.directory.api.asn1.EncoderException;
  import org.apache.directory.api.asn1.ber.Asn1Decoder;
  import org.apache.directory.api.asn1.ber.tlv.BerValue;
  import org.apache.directory.api.i18n.I18n;
  import org.apache.directory.api.ldap.codec.api.ControlDecorator;
  import org.apache.directory.api.ldap.codec.api.LdapApiService;
  import org.apache.directory.api.ldap.model.message.controls.Subentries;
  import org.apache.directory.api.ldap.model.message.controls.SubentriesImpl;
  
  
  /**
   * A Subentries Control implementation which wraps and decorates Subentries
   * Controls to enable them to be encoded and decoded by the codec.
   * 
   * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
   */
  public class SubentriesDecorator extends ControlDecorator<Subentries> implements Subentries
  {
      /** The sub entry decoder */
      private static final Asn1Decoder decoder = new Asn1Decoder();
  
  
      /**
       * Default constructor
       */
      public SubentriesDecorator( LdapApiService codec )
      {
          this( codec, new SubentriesImpl() );
      }
  
  
      /**
       * Creates a Subentries decorating implementation for use with the codec,
       * while decorating the supplied Subentries control.
       *
       * @param control The Subentries Control to wrap with this decorator.
       */
      public SubentriesDecorator( LdapApiService codec, Subentries control )
      {
          super( codec, control );
      }
  
  
      /**
       * Compute the SubEntryControl length 0x01 0x01 [0x00|0xFF]
       */
      public int computeLength()
      {
          return 1 + 1 + 1;
      }
  
  
      /**
       * Encodes the Subentries control.
       * 
       * @param buffer The encoded sink
       * @return A ByteBuffer that contains the encoded PDU
       * @throws org.apache.directory.api.asn1.EncoderException If anything goes wrong.
       */
      public ByteBuffer encode( ByteBuffer buffer ) throws EncoderException
      {
          if ( buffer == null )
          {
              throw new EncoderException( I18n.err( I18n.ERR_04023 ) );
          }
  
          // Now encode the Subentries specific part
          BerValue.encode( buffer, isVisible() );
  
          return buffer;
      }
  
  
     /**
      * {@inheritDoc}
      */
     public byte[] getValue()
     {
         if ( value == null )
         {
             try
             {
                 computeLength();
                 ByteBuffer buffer = ByteBuffer.allocate( valueLength );
 
                 // Now encode the Subentries specific part
                 BerValue.encode( buffer, isVisible() );
 
                 value = buffer.array();
             }
             catch ( Exception e )
             {
                 return null;
             }
         }
 
         return value;
     }
 
 
     public boolean isVisible()
     {
         return getDecorated().isVisible();
     }
 
 
     public void setVisibility( boolean visibility )
     {
         getDecorated().setVisibility( visibility );
     }
 
 
     /**
      * {@inheritDoc}
      */
     public Asn1Object decode( byte[] controlBytes ) throws DecoderException
     {
         ByteBuffer bb = ByteBuffer.wrap( controlBytes );
         SubentriesContainer container = new SubentriesContainer( this );
         decoder.decode( bb, container );
 
         return this;
     }
 }