/*
    * ====================================================================
    * 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.impl.nio.client;
  
  import java.io.Closeable;
  import java.net.URI;
  import java.util.concurrent.Future;
  
  import org.apache.http.HttpHost;
  import org.apache.http.HttpRequest;
  import org.apache.http.HttpResponse;
  import org.apache.http.annotation.Contract;
  import org.apache.http.annotation.ThreadingBehavior;
  import org.apache.http.client.ClientProtocolException;
  import org.apache.http.client.methods.HttpUriRequest;
  import org.apache.http.client.protocol.HttpClientContext;
  import org.apache.http.client.utils.URIUtils;
  import org.apache.http.concurrent.BasicFuture;
  import org.apache.http.concurrent.FutureCallback;
  import org.apache.http.nio.client.HttpAsyncClient;
  import org.apache.http.nio.client.methods.HttpAsyncMethods;
  import org.apache.http.nio.protocol.HttpAsyncRequestProducer;
  import org.apache.http.nio.protocol.HttpAsyncResponseConsumer;
  import org.apache.http.protocol.HttpContext;
  import org.apache.http.util.Args;
  
  /**
   * Base implementation of {@link HttpAsyncClient} that also implements {@link Closeable}.
   *
   * @since 4.0
   */
  @Contract(threading = ThreadingBehavior.SAFE)
  public abstract class CloseableHttpAsyncClient implements HttpAsyncClient, Closeable {
  
      public abstract boolean isRunning();
  
      public abstract void start();
  
      @Override
      public <T> Future<T> execute(
              final HttpAsyncRequestProducer requestProducer,
              final HttpAsyncResponseConsumer<T> responseConsumer,
              final FutureCallback<T> callback) {
          return execute(requestProducer, responseConsumer, HttpClientContext.create(), callback);
      }
  
      @Override
      public Future<HttpResponse> execute(
              final HttpHost target, final HttpRequest request, final HttpContext context,
              final FutureCallback<HttpResponse> callback) {
          return execute(
                  HttpAsyncMethods.create(target, request),
                  HttpAsyncMethods.createConsumer(),
                  context, callback);
      }
  
      @Override
      public Future<HttpResponse> execute(
              final HttpHost target, final HttpRequest request,
              final FutureCallback<HttpResponse> callback) {
          return execute(target, request, HttpClientContext.create(), callback);
      }
  
      @Override
      public Future<HttpResponse> execute(
              final HttpUriRequest request,
              final FutureCallback<HttpResponse> callback) {
          return execute(request, HttpClientContext.create(), callback);
      }
  
      @Override
      public Future<HttpResponse> execute(
              final HttpUriRequest request,
              final HttpContext context,
              final FutureCallback<HttpResponse> callback) {
         final HttpHost target;
         try {
             target = determineTarget(request);
         } catch (final ClientProtocolException ex) {
             final BasicFuture<HttpResponse> future = new BasicFuture<HttpResponse>(callback);
             future.failed(ex);
             return future;
         }
         return execute(target, request, context, callback);
     }
 
     private HttpHost determineTarget(final HttpUriRequest request) throws ClientProtocolException {
         Args.notNull(request, "HTTP request");
         // A null target may be acceptable if there is a default target.
         // Otherwise, the null target is detected in the director.
         HttpHost target = null;
 
         final URI requestURI = request.getURI();
         if (requestURI.isAbsolute()) {
             target = URIUtils.extractHost(requestURI);
             if (target == null) {
                 throw new ClientProtocolException(
                         "URI does not specify a valid host name: " + requestURI);
             }
         }
         return target;
     }
 
 }