/*
    * Copyright 2016 The Netty Project
    *
    * The Netty Project 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:
    *
    *   https://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 io.netty.handler.codec;
  
  import io.netty.buffer.ByteBuf;
  import io.netty.channel.ChannelHandlerContext;
  import io.netty.channel.ChannelPipeline;
  import io.netty.channel.socket.DatagramPacket;
  import io.netty.handler.codec.protobuf.ProtobufDecoder;
  import static io.netty.util.internal.ObjectUtil.checkNotNull;
  
  import java.util.List;
  
  /**
   * A decoder that decodes the content of the received {@link DatagramPacket} using
   * the specified {@link ByteBuf} decoder. E.g.,
   *
   * <pre><code>
   * {@link ChannelPipeline} pipeline = ...;
   * pipeline.addLast("udpDecoder", new {@link DatagramPacketDecoder}(new {@link ProtobufDecoder}(...));
   * </code></pre>
   */
  public class DatagramPacketDecoder extends MessageToMessageDecoder<DatagramPacket> {
  
      private final MessageToMessageDecoder<ByteBuf> decoder;
  
      /**
       * Create a {@link DatagramPacket} decoder using the specified {@link ByteBuf} decoder.
       *
       * @param decoder the specified {@link ByteBuf} decoder
       */
      public DatagramPacketDecoder(MessageToMessageDecoder<ByteBuf> decoder) {
          this.decoder = checkNotNull(decoder, "decoder");
      }
  
      @Override
      public boolean acceptInboundMessage(Object msg) throws Exception {
          if (msg instanceof DatagramPacket) {
              return decoder.acceptInboundMessage(((DatagramPacket) msg).content());
          }
          return false;
      }
  
      @Override
      protected void decode(ChannelHandlerContext ctx, DatagramPacket msg, List<Object> out) throws Exception {
          decoder.decode(ctx, msg.content(), out);
      }
  
      @Override
      public void channelRegistered(ChannelHandlerContext ctx) throws Exception {
          decoder.channelRegistered(ctx);
      }
  
      @Override
      public void channelUnregistered(ChannelHandlerContext ctx) throws Exception {
          decoder.channelUnregistered(ctx);
      }
  
      @Override
      public void channelActive(ChannelHandlerContext ctx) throws Exception {
          decoder.channelActive(ctx);
      }
  
      @Override
      public void channelInactive(ChannelHandlerContext ctx) throws Exception {
          decoder.channelInactive(ctx);
      }
  
      @Override
      public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {
          decoder.channelReadComplete(ctx);
      }
  
      @Override
      public void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exception {
          decoder.userEventTriggered(ctx, evt);
      }
  
      @Override
      public void channelWritabilityChanged(ChannelHandlerContext ctx) throws Exception {
          decoder.channelWritabilityChanged(ctx);
      }
  
      @Override
      public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
          decoder.exceptionCaught(ctx, cause);
     }
 
     @Override
     public void handlerAdded(ChannelHandlerContext ctx) throws Exception {
         decoder.handlerAdded(ctx);
     }
 
     @Override
     public void handlerRemoved(ChannelHandlerContext ctx) throws Exception {
         decoder.handlerRemoved(ctx);
     }
 
     @Override
     public boolean isSharable() {
         return decoder.isSharable();
     }
 }