/*
    * Copyright 2013 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.memcache.binary;
  
  import io.netty.buffer.ByteBuf;
  import io.netty.handler.codec.memcache.AbstractMemcacheObjectAggregator;
  import io.netty.handler.codec.memcache.FullMemcacheMessage;
  import io.netty.handler.codec.memcache.MemcacheContent;
  import io.netty.handler.codec.memcache.MemcacheObject;
  import io.netty.util.internal.UnstableApi;
  
  import static io.netty.util.internal.StringUtil.className;
  
  /**
   * An object aggregator for the memcache binary protocol.
   *
   * It aggregates {@link BinaryMemcacheMessage}s and {@link MemcacheContent} into {@link FullBinaryMemcacheRequest}s
   * or {@link FullBinaryMemcacheResponse}s.
   */
  @UnstableApi
  public class BinaryMemcacheObjectAggregator extends AbstractMemcacheObjectAggregator<BinaryMemcacheMessage> {
  
      public BinaryMemcacheObjectAggregator(int maxContentLength) {
          super(maxContentLength);
      }
  
      @Override
      protected boolean isStartMessage(MemcacheObject msg) throws Exception {
          return msg instanceof BinaryMemcacheMessage;
      }
  
      @Override
      protected FullMemcacheMessage beginAggregation(BinaryMemcacheMessage start, ByteBuf content) throws Exception {
          if (start instanceof BinaryMemcacheRequest) {
              return toFullRequest((BinaryMemcacheRequest) start, content);
          }
  
          if (start instanceof BinaryMemcacheResponse) {
              return toFullResponse((BinaryMemcacheResponse) start, content);
          }
  
          // Should not reach here.
          throw new Error("Unexpected memcache message type: " + className(start));
      }
  
      private static FullBinaryMemcacheRequest toFullRequest(BinaryMemcacheRequest request, ByteBuf content) {
          ByteBuf key = request.key() == null ? null : request.key().retain();
          ByteBuf extras = request.extras() == null ? null : request.extras().retain();
          DefaultFullBinaryMemcacheRequest fullRequest =
                  new DefaultFullBinaryMemcacheRequest(key, extras, content);
  
          fullRequest.setMagic(request.magic());
          fullRequest.setOpcode(request.opcode());
          fullRequest.setKeyLength(request.keyLength());
          fullRequest.setExtrasLength(request.extrasLength());
          fullRequest.setDataType(request.dataType());
          fullRequest.setTotalBodyLength(request.totalBodyLength());
          fullRequest.setOpaque(request.opaque());
          fullRequest.setCas(request.cas());
          fullRequest.setReserved(request.reserved());
  
          return fullRequest;
      }
  
      private static FullBinaryMemcacheResponse toFullResponse(BinaryMemcacheResponse response, ByteBuf content) {
          ByteBuf key = response.key() == null ? null : response.key().retain();
          ByteBuf extras = response.extras() == null ? null : response.extras().retain();
          DefaultFullBinaryMemcacheResponse fullResponse =
                  new DefaultFullBinaryMemcacheResponse(key, extras, content);
  
          fullResponse.setMagic(response.magic());
          fullResponse.setOpcode(response.opcode());
          fullResponse.setKeyLength(response.keyLength());
          fullResponse.setExtrasLength(response.extrasLength());
          fullResponse.setDataType(response.dataType());
          fullResponse.setTotalBodyLength(response.totalBodyLength());
          fullResponse.setOpaque(response.opaque());
          fullResponse.setCas(response.cas());
          fullResponse.setStatus(response.status());
  
          return fullResponse;
      }
  }