/*
    *  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.mina.core.write;
  
  import java.net.SocketAddress;
  import java.util.concurrent.TimeUnit;
  
  import org.apache.mina.core.buffer.IoBuffer;
  import org.apache.mina.core.future.IoFutureListener;
  import org.apache.mina.core.future.WriteFuture;
  import org.apache.mina.core.session.IoSession;
  
  /**
   * The default implementation of {@link WriteRequest}.
   *
   * @author <a href="http://mina.apache.org">Apache MINA Project</a>
   */
  public class DefaultWriteRequest implements WriteRequest {
      /** An empty message */
      public static final byte[] EMPTY_MESSAGE = new byte[] {};
  
      /** An empty FUTURE */
      private static final WriteFuturere.html#WriteFuture">WriteFuture UNUSED_FUTURE = new WriteFuture() {
          /**
           * {@inheritDoc}
           */
          @Override
          public boolean isWritten() {
              return false;
          }
  
          /**
           * {@inheritDoc}
           */
          @Override
          public void setWritten() {
              // Do nothing
          }
  
          /**
           * {@inheritDoc}
           */
          @Override
          public IoSession getSession() {
              return null;
          }
  
          /**
           * {@inheritDoc}
           */
          @Override
          public void join() {
              // Do nothing
          }
  
          /**
           * {@inheritDoc}
           */
          @Override
          public boolean join(long timeoutInMillis) {
              return true;
          }
  
          /**
           * {@inheritDoc}
           */
          @Override
          public boolean isDone() {
              return true;
          }
  
          /**
           * {@inheritDoc}
           */
          @Override
          public WriteFuture addListener(IoFutureListener<?> listener) {
              throw new IllegalStateException("You can't add a listener to a dummy future.");
          }
  
          /**
           * {@inheritDoc}
           */
         @Override
         public WriteFuture removeListener(IoFutureListener<?> listener) {
             throw new IllegalStateException("You can't add a listener to a dummy future.");
         }
 
         /**
          * {@inheritDoc}
          */
         @Override
         public WriteFuture await() throws InterruptedException {
             return this;
         }
 
         /**
          * {@inheritDoc}
          */
         @Override
         public boolean await(long timeout, TimeUnit unit) throws InterruptedException {
             return true;
         }
 
         /**
          * {@inheritDoc}
          */
         @Override
         public boolean await(long timeoutMillis) throws InterruptedException {
             return true;
         }
 
         /**
          * {@inheritDoc}
          */
         @Override
         public WriteFuture awaitUninterruptibly() {
             return this;
         }
 
         /**
          * {@inheritDoc}
          */
         @Override
         public boolean awaitUninterruptibly(long timeout, TimeUnit unit) {
             return true;
         }
 
         /**
          * {@inheritDoc}
          */
         @Override
         public boolean awaitUninterruptibly(long timeoutMillis) {
             return true;
         }
 
         /**
          * {@inheritDoc}
          */
         @Override
         public Throwable getException() {
             return null;
         }
 
         /**
          * {@inheritDoc}
          */
         @Override
         public void setException(Throwable cause) {
             // Do nothing
         }
     };
 
     /** 
      * The original message as it was written by the IoHandler. It will be sent back
      * in the messageSent event 
      */ 
     private final Object originalMessage;
 
     /** The message that will ultimately be written to the remote peer */ 
     private Object message;
 
     /** The associated Future */
     private final WriteFuture future;
 
     /** The peer destination (useless ???) */
     private final SocketAddress destination;
 
     /**
      * Creates a new instance without {@link WriteFuture}.  You'll get
      * an instance of {@link WriteFuture} even if you called this constructor
      * because {@link #getFuture()} will return a bogus future.
      * 
      * @param message The message that will be written
      */
     public DefaultWriteRequest(Object message) {
         this(message, null, null);
     }
 
     /**
      * Creates a new instance with {@link WriteFuture}.
      * 
      * @param message The message that will be written
      * @param future The associated {@link WriteFuture}
      */
     public DefaultWriteRequest(Object message, WriteFuture future) {
         this(message, future, null);
     }
 
     /**
      * Creates a new instance.
      *
      * @param message a message to write
      * @param future a future that needs to be notified when an operation is finished
      * @param destination the destination of the message.  This property will be
      *                    ignored unless the transport supports it.
      */
     public DefaultWriteRequest(Object message, WriteFuture future, SocketAddress destination) {
         if (message == null) {
             throw new IllegalArgumentException("message");
         }
 
         if (future == null) {
             future = UNUSED_FUTURE;
         }
 
         this.message = message;
         this.originalMessage = message;
         
         if (message instanceof IoBuffer) {
             // duplicate it, so that any modification made on it
             // won't change the original message
             this.message = ((IoBuffer)message).duplicate();
         }
 
         
         this.future = future;
         this.destination = destination;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public WriteFuture getFuture() {
         return future;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public Object getMessage() {
         return message;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void setMessage(Object modifiedMessage) {
         message = modifiedMessage;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public Object getOriginalMessage() {
         if (originalMessage != null) {
             return originalMessage;
         } else {
             return message;
         }
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public WriteRequest getOriginalRequest() {
         return this;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public SocketAddress getDestination() {
         return destination;
     }
 
     @Override
     public String toString() {
         StringBuilder sb = new StringBuilder();
 
         sb.append("WriteRequest: ");
 
         // Special case for the CLOSE_REQUEST writeRequest : it just
         // carries a native Object instance
         if (message.getClass().getName().equals(Object.class.getName())) {
             sb.append("CLOSE_REQUEST");
         } else {
             sb.append(originalMessage);
 
             if (getDestination() != null) {
                 sb.append(" => ");
                 sb.append(getDestination());
             }
         }
 
         return sb.toString();
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public boolean isEncoded() {
         return false;
     }
 }