/*
    * ====================================================================
    * 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.
   * ====================================================================
   *
   * This software consists of voluntary contributions made by many
   * individuals on behalf of the Apache Software Foundation.  For more
   * information on the Apache Software Foundation, please see
   * <http://www.apache.org/>.
   *
   */
  package org.apache.http.nio.protocol;
  
  import java.io.IOException;
  
  import org.apache.http.ContentTooLongException;
  import org.apache.http.HttpEntity;
  import org.apache.http.HttpResponse;
  import org.apache.http.entity.ContentType;
  import org.apache.http.nio.ContentDecoder;
  import org.apache.http.nio.IOControl;
  import org.apache.http.nio.entity.ContentBufferEntity;
  import org.apache.http.nio.util.HeapByteBufferAllocator;
  import org.apache.http.nio.util.SimpleInputBuffer;
  import org.apache.http.protocol.HttpContext;
  import org.apache.http.util.Asserts;
  
  /**
   * Basic implementation of {@link HttpAsyncResponseConsumer}. Please note that
   * this consumer buffers response content in memory and should be used for
   * relatively small response messages.
   *
   * @since 4.2
   */
  public class BasicAsyncResponseConsumer extends AbstractAsyncResponseConsumer<HttpResponse> {
  
      private static final int MAX_INITIAL_BUFFER_SIZE = 256 * 1024;
  
      private volatile HttpResponse response;
      private volatile SimpleInputBuffer buf;
  
      public BasicAsyncResponseConsumer() {
          super();
      }
  
      @Override
      protected void onResponseReceived(final HttpResponse response) throws IOException {
          this.response = response;
      }
  
      @Override
      protected void onEntityEnclosed(
              final HttpEntity entity, final ContentType contentType) throws IOException {
          long len = entity.getContentLength();
          if (len > Integer.MAX_VALUE) {
              throw new ContentTooLongException("Entity content is too long: %,d", len);
          }
          if (len < 0) {
              len = 4096;
          }
          final int initialBufferSize = Math.min((int) len, MAX_INITIAL_BUFFER_SIZE);
          this.buf = new SimpleInputBuffer(initialBufferSize, new HeapByteBufferAllocator());
          this.response.setEntity(new ContentBufferEntity(entity, this.buf));
      }
  
      @Override
      protected void onContentReceived(
              final ContentDecoder decoder, final IOControl ioControl) throws IOException {
          Asserts.notNull(this.buf, "Content buffer");
          this.buf.consumeContent(decoder);
      }
  
      @Override
      protected void releaseResources() {
          this.response = null;
          this.buf = null;
      }
  
      @Override
      protected HttpResponse buildResult(final HttpContext context) {
          return this.response;
      }
  
  }