/*
    *  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.api;
  
  
  import org.apache.directory.api.asn1.Asn1Object;
  import org.apache.directory.api.ldap.model.message.Control;
  
  
  /**
   * Decorates Control objects by wrapping them, and enabling them as CodecControls
   * so the codec to store transient information associated with the Control in the
   * decorator while processing.
   * 
   * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
   * @param <E> The control type
   */
  public abstract class ControlDecorator<E extends Control> implements CodecControl<E>, Asn1Object
  {
      /** The decorated Control */
      private E decorated;
  
      /** The encoded value length */
      protected int valueLength;
  
      /** The encoded value of the control. */
      protected byte[] value;
  
      /** The codec service responsible for encoding decoding this object */
      private LdapApiService codec;
  
  
      /**
       * Creates a ControlDecorator to codec enable it.
       *
       * @param codec The Ldap service to use
       * @param decoratedControl The Control to decorate.
       */
      public ControlDecorator( LdapApiService codec, E decoratedControl )
      {
          this.decorated = decoratedControl;
          this.codec = codec;
      }
  
  
      /**
       * {@inheritDoc}
       */
      @Override
      public E getDecorated()
      {
          return decorated;
      }
  
  
      /**
       * Set the control to be decorated.
       * 
       * @param decorated The decorated control
       */
      public void setDecorated( E decorated )
      {
          this.decorated = decorated;
      }
  
  
      /**
       * {@inheritDoc}
       */
      @Override
      public LdapApiService getCodecService()
      {
          return codec;
      }
  
  
      // ------------------------------------------------------------------------
      // Control Methods
      // ------------------------------------------------------------------------
  
      /**
       * Get the control OID
      * 
      * @return A string which represent the control oid
      */
     @Override
     public String getOid()
     {
         return decorated.getOid();
     }
 
 
     /**
      * {@inheritDoc}
      */
     @Override
     public boolean hasValue()
     {
         return value != null;
     }
 
 
     /**
      * Get the control value
      * 
      * @return The control value
      */
     @Override
     public byte[] getValue()
     {
         return value;
     }
 
 
     /**
      * Set the encoded control value
      * 
      * @param value The encoded control value to store
      */
     @Override
     public void setValue( byte[] value )
     {
         if ( value != null )
         {
             byte[] copy = new byte[value.length];
             System.arraycopy( value, 0, copy, 0, value.length );
             this.value = copy;
         }
         else
         {
             this.value = null;
         }
     }
 
 
     /**
      * Get the criticality
      * 
      * @return <code>true</code> if the criticality flag is true.
      */
     @Override
     public boolean isCritical()
     {
         return decorated.isCritical();
     }
 
 
     /**
      * Set the criticality
      * 
      * @param criticality The criticality value
      */
     @Override
     public void setCritical( boolean criticality )
     {
         decorated.setCritical( criticality );
     }
 
 
     // ------------------------------------------------------------------------
     // CodecControl Methods
     // ------------------------------------------------------------------------
     /**
      * {@inheritDoc}
      */
     @Override
     public int computeLength()
     {
         return 0;
     }
 
 
     // ------------------------------------------------------------------------
     // Object Method Overrides
     // ------------------------------------------------------------------------
     /**
      * @see Object#hashCode()
      */
     @Override
     public int hashCode()
     {
         return decorated.hashCode();
     }
 
 
     /**
      * @see Object#equals(Object)
      */
     @Override
     public boolean equals( Object o )
     {
         if ( decorated == null )
         {
             return o == null;
         }
         else
         {
             return decorated.equals( o );
         }
     }
 
 
     /**
      * Return a String representing a Control
      */
     @Override
     public String toString()
     {
         return decorated.toString();
     }
 }