/*
    *   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.cancel;
  
  
  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.tlv.BerValue;
  import org.apache.directory.api.asn1.ber.tlv.TLV;
  import org.apache.directory.api.asn1.ber.tlv.UniversalTag;
  import org.apache.directory.api.i18n.I18n;
  import org.apache.directory.api.ldap.codec.api.ExtendedRequestDecorator;
  import org.apache.directory.api.ldap.codec.api.LdapApiService;
  import org.apache.directory.api.ldap.extras.extended.cancel.CancelRequest;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  
  /**
   * A Decorator for CancelRequests.
   *
   * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
   */
  public class CancelRequestDecorator extends ExtendedRequestDecorator<CancelRequest> implements
      CancelRequest, Asn1Object
  {
      private static final Logger LOG = LoggerFactory.getLogger( CancelRequestDecorator.class );
  
      /** The Id of the the message to cancel */
      private CancelRequest cancelRequest;
  
      /** Length of the sequence */
      private int cancelSequenceLength;
  
  
      /**
       * Creates a new instance of CancelRequestDecorator.
       * 
       * @param codec The LDAP Service to use
       * @param decoratedMessage The canceled request
       */
      public CancelRequestDecorator( LdapApiService codec, CancelRequest decoratedMessage )
      {
          super( codec, decoratedMessage );
          cancelRequest = decoratedMessage;
      }
  
  
      /**
       * {@inheritDoc}
       */
      @Override
      public int getCancelId()
      {
          return cancelRequest.getCancelId();
      }
  
  
      /**
       * {@inheritDoc}
       */
      @Override
      public void setCancelId( int cancelId )
      {
          if ( cancelId == cancelRequest.getCancelId() )
          {
              return;
          }
  
          this.requestValue = null;
          cancelRequest.setCancelId( cancelId );
      }
  
  
      /**
       * {@inheritDoc}
       */
      @Override
      public byte[] getRequestValue()
     {
         if ( requestValue == null )
         {
             try
             {
                 requestValue = encodeInternal().array();
             }
             catch ( EncoderException e )
             {
                 LOG.error( I18n.err( I18n.ERR_04164 ), e );
                 throw new RuntimeException( e );
             }
         }
 
         return requestValue;
     }
 
 
     /**
      * Sets the extended request's <b>requestValue</b> portion of the PDU.
      *
      * @param requestValue byte array of data encapsulating ext. req. parameters
      */
     @Override
     public void setRequestValue( byte[] requestValue )
     {
         CancelDecoder decoder = new CancelDecoder();
 
         try
         {
             if ( requestValue != null )
             {
                 CancelRequest cancel = decoder.decode( requestValue );
                 cancelRequest.setCancelId( cancel.getCancelId() );
 
                 this.requestValue = new byte[requestValue.length];
                 System.arraycopy( requestValue, 0, this.requestValue, 0, requestValue.length );
             }
             else
             {
                 this.requestValue = null;
                 cancelRequest.setCancelId( 0 );
             }
 
         }
         catch ( DecoderException e )
         {
             LOG.error( I18n.err( I18n.ERR_04165 ), e );
             throw new RuntimeException( e );
         }
     }
 
 
     /**
      * Compute the Cancel length 
      * <pre>
      * 0x30 L1 
      *   | 
      *   +--&gt; 0x02 0x0(1-4) [0..2^31-1]
      * </pre> 
      */
     /* no qualifier */int computeLengthInternal()
     {
         // The messageId length
         cancelSequenceLength = 1 + 1 + BerValue.getNbBytes( cancelRequest.getCancelId() );
 
         // Add the sequence and the length
         return 1 + 1 + cancelSequenceLength;
     }
 
 
     /**
      * Encodes the cancel extended operation.
      * 
      * @return A ByteBuffer that contains the encoded PDU
      * @throws org.apache.directory.api.asn1.EncoderException If anything goes wrong.
      */
     /* no qualifier */ByteBuffer encodeInternal() throws EncoderException
     {
         // Allocate the bytes buffer.
         ByteBuffer bb = ByteBuffer.allocate( computeLengthInternal() );
 
         // The sequence
         bb.put( UniversalTag.SEQUENCE.getValue() );
         bb.put( TLV.getBytes( cancelSequenceLength ) );
 
         // The messageId
         BerValue.encode( bb, cancelRequest.getCancelId() );
 
         return bb;
     }
 }