/*
    * ====================================================================
    * 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.hc.client5.http.examples;
  
  import java.nio.ByteBuffer;
  import java.nio.CharBuffer;
  import java.util.concurrent.Future;
  
  import org.apache.hc.client5.http.async.methods.AbstractBinPushConsumer;
  import org.apache.hc.client5.http.async.methods.AbstractCharResponseConsumer;
  import org.apache.hc.client5.http.config.TlsConfig;
  import org.apache.hc.client5.http.impl.async.CloseableHttpAsyncClient;
  import org.apache.hc.client5.http.impl.async.HttpAsyncClients;
  import org.apache.hc.client5.http.impl.nio.PoolingAsyncClientConnectionManagerBuilder;
  import org.apache.hc.core5.function.Supplier;
  import org.apache.hc.core5.http.ContentType;
  import org.apache.hc.core5.http.HttpHost;
  import org.apache.hc.core5.http.HttpRequest;
  import org.apache.hc.core5.http.HttpResponse;
  import org.apache.hc.core5.http.impl.routing.RequestRouter;
  import org.apache.hc.core5.http.message.BasicHttpRequest;
  import org.apache.hc.core5.http.message.StatusLine;
  import org.apache.hc.core5.http.nio.AsyncPushConsumer;
  import org.apache.hc.core5.http.nio.support.BasicRequestProducer;
  import org.apache.hc.core5.http.support.BasicRequestBuilder;
  import org.apache.hc.core5.http2.HttpVersionPolicy;
  import org.apache.hc.core5.http2.config.H2Config;
  import org.apache.hc.core5.io.CloseMode;
  
  /**
   * This example demonstrates handling of HTTP/2 message exchanges pushed by the server.
   */
  public class AsyncClientH2ServerPush {
  
      public static void main(final String[] args) throws Exception {
  
          final CloseableHttpAsyncClient client = HttpAsyncClients.custom()
                  .setH2Config(H2Config.custom()
                          .setPushEnabled(true)
                          .build())
                  .setConnectionManager(PoolingAsyncClientConnectionManagerBuilder.create()
                          .setDefaultTlsConfig(TlsConfig.custom()
                                  .setVersionPolicy(HttpVersionPolicy.FORCE_HTTP_2)
                                  .build())
                          .build())
                  .build();
  
          client.start();
  
          final RequestRouter<Supplier<AsyncPushConsumer>> pushRequestRouter = RequestRouter.<Supplier<AsyncPushConsumer>>builder()
                  // Route all requests to the local authority
                  .resolveAuthority(RequestRouter.LOCAL_AUTHORITY_RESOLVER)
                  // Use the same route for all requests
                  .addRoute(RequestRouter.LOCAL_AUTHORITY, "*", () -> new AbstractBinPushConsumer() {
  
                      @Override
                      protected void start(
                              final HttpRequest promise,
                              final HttpResponse response,
                              final ContentType contentType) {
                          System.out.println(promise.getPath() + " (push)->" + new StatusLine(response));
                      }
  
                      @Override
                      protected int capacityIncrement() {
                          return Integer.MAX_VALUE;
                      }
  
                      @Override
                      protected void data(final ByteBuffer data, final boolean endOfStream) {
                      }
  
                      @Override
                      protected void completed() {
                      }
 
                     @Override
                     public void failed(final Exception cause) {
                         System.out.println("(push)->" + cause);
                     }
 
                     @Override
                     public void releaseResources() {
                     }
 
                 })
                 .build();
 
         final HttpHost target = new HttpHost("https", "nghttp2.org");
 
         final BasicHttpRequest request = BasicRequestBuilder.get()
                 .setHttpHost(target)
                 .setPath("/httpbin/")
                 .build();
 
         System.out.println("Executing request " + request);
         final Future<Void> future = client.execute(
                 new BasicRequestProducer(request, null),
                 new AbstractCharResponseConsumer<Void>() {
 
                     @Override
                     protected void start(
                             final HttpResponse response,
                             final ContentType contentType) {
                         System.out.println(request + "->" + new StatusLine(response));
                     }
 
                     @Override
                     protected int capacityIncrement() {
                         return Integer.MAX_VALUE;
                     }
 
                     @Override
                     protected void data(final CharBuffer data, final boolean endOfStream) {
                     }
 
                     @Override
                     protected Void buildResult() {
                         return null;
                     }
 
                     @Override
                     public void failed(final Exception cause) {
                         System.out.println(request + "->" + cause);
                     }
 
                     @Override
                     public void releaseResources() {
                     }
 
                 },
                 HttpAsyncClients.pushRouter(pushRequestRouter),
                 null,
                 null);
         future.get();
 
         System.out.println("Shutting down");
         client.close(CloseMode.GRACEFUL);
     }
 
 }