/*
    * ====================================================================
    * 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.core5.http2.examples;
  
  import java.util.List;
  import java.util.concurrent.CountDownLatch;
  import java.util.concurrent.Future;
  import java.util.concurrent.TimeUnit;
  
  import org.apache.hc.core5.concurrent.FutureCallback;
  import org.apache.hc.core5.http.Header;
  import org.apache.hc.core5.http.HttpConnection;
  import org.apache.hc.core5.http.HttpHost;
  import org.apache.hc.core5.http.HttpResponse;
  import org.apache.hc.core5.http.Message;
  import org.apache.hc.core5.http.impl.bootstrap.HttpAsyncRequester;
  import org.apache.hc.core5.http.nio.AsyncClientEndpoint;
  import org.apache.hc.core5.http.nio.entity.StringAsyncEntityConsumer;
  import org.apache.hc.core5.http.nio.support.AsyncRequestBuilder;
  import org.apache.hc.core5.http.nio.support.BasicResponseConsumer;
  import org.apache.hc.core5.http2.HttpVersionPolicy;
  import org.apache.hc.core5.http2.config.H2Config;
  import org.apache.hc.core5.http2.frame.RawFrame;
  import org.apache.hc.core5.http2.impl.nio.H2StreamListener;
  import org.apache.hc.core5.http2.impl.nio.bootstrap.H2RequesterBootstrap;
  import org.apache.hc.core5.io.CloseMode;
  import org.apache.hc.core5.reactor.IOReactorConfig;
  import org.apache.hc.core5.util.Timeout;
  
  /**
   * Example of HTTP/2 concurrent request execution using multiple streams.
   */
  public class H2MultiStreamExecutionExample {
  
      public static void main(final String[] args) throws Exception {
  
          // Create and start requester
          final IOReactorConfig ioReactorConfig = IOReactorConfig.custom()
                  .setSoTimeout(5, TimeUnit.SECONDS)
                  .build();
  
          final H2Config h2Config = H2Config.custom()
                  .setPushEnabled(false)
                  .setMaxConcurrentStreams(100)
                  .build();
  
          final HttpAsyncRequester requester = H2RequesterBootstrap.bootstrap()
                  .setIOReactorConfig(ioReactorConfig)
                  .setVersionPolicy(HttpVersionPolicy.FORCE_HTTP_2)
                  .setH2Config(h2Config)
                  .setStreamListener(new H2StreamListener() {
  
                      @Override
                      public void onHeaderInput(final HttpConnection connection, final int streamId, final List<? extends Header> headers) {
                          for (int i = 0; i < headers.size(); i++) {
                              System.out.println(connection.getRemoteAddress() + " (" + streamId + ") << " + headers.get(i));
                          }
                      }
  
                      @Override
                      public void onHeaderOutput(final HttpConnection connection, final int streamId, final List<? extends Header> headers) {
                          for (int i = 0; i < headers.size(); i++) {
                              System.out.println(connection.getRemoteAddress() + " (" + streamId + ") >> " + headers.get(i));
                          }
                      }
  
                      @Override
                      public void onFrameInput(final HttpConnection connection, final int streamId, final RawFrame frame) {
                      }
  
                      @Override
                      public void onFrameOutput(final HttpConnection connection, final int streamId, final RawFrame frame) {
                      }
  
                      @Override
                     public void onInputFlowControl(final HttpConnection connection, final int streamId, final int delta, final int actualSize) {
                     }
 
                     @Override
                     public void onOutputFlowControl(final HttpConnection connection, final int streamId, final int delta, final int actualSize) {
                     }
 
                 })
                 .create();
         Runtime.getRuntime().addShutdownHook(new Thread() {
             @Override
             public void run() {
                 System.out.println("HTTP requester shutting down");
                 requester.close(CloseMode.GRACEFUL);
             }
         });
         requester.start();
 
         final HttpHost target = new HttpHost("nghttp2.org");
         final String[] requestUris = new String[] {"/httpbin/ip", "/httpbin/user-agent", "/httpbin/headers"};
 
         final Future<AsyncClientEndpoint> future = requester.connect(target, Timeout.ofSeconds(5));
         final AsyncClientEndpoint clientEndpoint = future.get();
 
         final CountDownLatch latch = new CountDownLatch(requestUris.length);
         for (final String requestUri: requestUris) {
             clientEndpoint.execute(
                     AsyncRequestBuilder.get()
                             .setHttpHost(target)
                             .setPath(requestUri)
                             .build(),
                     new BasicResponseConsumer<>(new StringAsyncEntityConsumer()),
                     new FutureCallback<Message<HttpResponse, String>>() {
 
                         @Override
                         public void completed(final Message<HttpResponse, String> message) {
                             latch.countDown();
                             final HttpResponse response = message.getHead();
                             final String body = message.getBody();
                             System.out.println(requestUri + "->" + response.getCode());
                             System.out.println(body);
                         }
 
                         @Override
                         public void failed(final Exception ex) {
                             latch.countDown();
                             System.out.println(requestUri + "->" + ex);
                         }
 
                         @Override
                         public void cancelled() {
                             latch.countDown();
                             System.out.println(requestUri + " cancelled");
                         }
 
                     });
         }
 
         latch.await();
 
         // Manually release client endpoint when done !!!
         clientEndpoint.releaseAndDiscard();
 
         System.out.println("Shutting down I/O reactor");
         requester.initiateShutdown();
     }
 
 }