/*
    *  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.decorators;
  
  
  import java.nio.BufferOverflowException;
  import java.nio.ByteBuffer;
  
  import org.apache.directory.api.asn1.EncoderException;
  import org.apache.directory.api.asn1.ber.tlv.TLV;
  import org.apache.directory.api.i18n.I18n;
  import org.apache.directory.api.ldap.codec.api.LdapApiService;
  import org.apache.directory.api.ldap.codec.api.LdapCodecConstants;
  import org.apache.directory.api.ldap.codec.api.MessageDecorator;
  import org.apache.directory.api.ldap.model.message.IntermediateResponse;
  import org.apache.directory.api.util.Strings;
  
  
  /**
   * A decorator for the IntermediateResponse message
   *
   * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
   */
  public class IntermediateResponseDecorator extends MessageDecorator<IntermediateResponse>
      implements IntermediateResponse
  {
      /** The response name as a byte[] */
      private byte[] responseNameBytes;
  
      /** The encoded intermediateResponse length */
      private int intermediateResponseLength;
  
  
      /**
       * Makes a IntermediateResponse encodable.
       *
       * @param decoratedMessage the decorated IntermediateResponse
       */
      public IntermediateResponseDecorator( LdapApiService codec, IntermediateResponse decoratedMessage )
      {
          super( codec, decoratedMessage );
      }
  
  
      /**
       * Stores the encoded length for the IntermediateResponse
       *
       * @param intermediateResponseLength The encoded length
       */
      public void setIntermediateResponseLength( int intermediateResponseLength )
      {
          this.intermediateResponseLength = intermediateResponseLength;
      }
  
  
      /**
       * @return The encoded IntermediateResponse's length
       */
      public int getIntermediateResponseLength()
      {
          return intermediateResponseLength;
      }
  
  
      /**
       * Gets the ResponseName bytes
       *
       * @return the ResponseName bytes of the Intermediate response type.
       */
      public byte[] getResponseNameBytes()
      {
          return responseNameBytes;
      }
  
  
      /**
       * Sets the ResponseName bytes
       *
       * @param responseNameBytes the ResponseName bytes of the Intermediate response type.
       */
      public void setResponseNameBytes( byte[] responseNameBytes )
      {
         this.responseNameBytes = responseNameBytes;
     }
 
 
     //-------------------------------------------------------------------------
     // The IntermediateResponse methods
     //-------------------------------------------------------------------------
 
     /**
      * {@inheritDoc}
      */
     public String getResponseName()
     {
         return getDecorated().getResponseName();
     }
 
 
     /**
      * {@inheritDoc}
      */
     public void setResponseName( String oid )
     {
         getDecorated().setResponseName( oid );
     }
 
 
     /**
      * {@inheritDoc}
      */
     public byte[] getResponseValue()
     {
         return getDecorated().getResponseValue();
     }
 
 
     /**
      * {@inheritDoc}
      */
     public void setResponseValue( byte[] value )
     {
         getDecorated().setResponseValue( value );
     }
 
 
     //-------------------------------------------------------------------------
     // The Decorator methods
     //-------------------------------------------------------------------------
     /**
      * Compute the intermediateResponse length
      * 
      * intermediateResponse :
      * 
      * 0x79 L1
      *  |
      * [+--> 0x80 L2 name
      * [+--> 0x81 L3 response]]
      * 
      * L1 = [ + Length(0x80) + Length(L2) + L2
      *      [ + Length(0x81) + Length(L3) + L3]]
      * 
      * Length(IntermediateResponse) = Length(0x79) + Length(L1) + L1
      * 
      * @return The IntermediateResponse length
      */
     public int computeLength()
     {
         int intermediateResponseLength = 0;
 
         if ( !Strings.isEmpty( getResponseName() ) )
         {
             byte[] responseNameBytes = Strings.getBytesUtf8( getResponseName() );
 
             int responseNameLength = responseNameBytes.length;
             intermediateResponseLength += 1 + TLV.getNbBytes( responseNameLength ) + responseNameLength;
             setResponseNameBytes( responseNameBytes );
         }
 
         byte[] encodedValue = getResponseValue();
 
         if ( encodedValue != null )
         {
             intermediateResponseLength += 1 + TLV.getNbBytes( encodedValue.length ) + encodedValue.length;
         }
 
         setIntermediateResponseLength( intermediateResponseLength );
 
         return 1 + TLV.getNbBytes( intermediateResponseLength ) + intermediateResponseLength;
     }
 
 
     /**
      * Encode the IntermediateResponse message to a PDU. 
      * IntermediateResponse :
      *   0x79 LL
      *     [0x80 LL response name]
      *     [0x81 LL responseValue]
      * 
      * @param buffer The buffer where to put the PDU
      */
     public ByteBuffer encode( ByteBuffer buffer ) throws EncoderException
     {
         try
         {
             // The ExtendedResponse Tag
             buffer.put( LdapCodecConstants.INTERMEDIATE_RESPONSE_TAG );
             buffer.put( TLV.getBytes( getIntermediateResponseLength() ) );
 
             // The responseName, if any
             byte[] responseNameBytes = getResponseNameBytes();
 
             if ( ( responseNameBytes != null ) && ( responseNameBytes.length != 0 ) )
             {
                 buffer.put( ( byte ) LdapCodecConstants.INTERMEDIATE_RESPONSE_NAME_TAG );
                 buffer.put( TLV.getBytes( responseNameBytes.length ) );
                 buffer.put( responseNameBytes );
             }
 
             // The encodedValue, if any
             byte[] encodedValue = getResponseValue();
 
             if ( encodedValue != null )
             {
                 buffer.put( ( byte ) LdapCodecConstants.INTERMEDIATE_RESPONSE_VALUE_TAG );
 
                 buffer.put( TLV.getBytes( encodedValue.length ) );
 
                 if ( encodedValue.length != 0 )
                 {
                     buffer.put( encodedValue );
                 }
             }
         }
         catch ( BufferOverflowException boe )
         {
             throw new EncoderException( I18n.err( I18n.ERR_04005 ) );
         }
 
         return buffer;
     }
 }