/*
    * ====================================================================
    * 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/>.
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   */
  package org.apache.hc.client5.http.examples;
  
  import org.apache.hc.client5.http.auth.AuthExchange;
  import org.apache.hc.client5.http.auth.AuthScheme;
  import org.apache.hc.client5.http.auth.AuthScope;
  import org.apache.hc.client5.http.auth.UsernamePasswordCredentials;
  import org.apache.hc.client5.http.classic.methods.HttpGet;
  import org.apache.hc.client5.http.impl.auth.BasicCredentialsProvider;
  import org.apache.hc.client5.http.impl.auth.DigestScheme;
  import org.apache.hc.client5.http.impl.classic.CloseableHttpClient;
  import org.apache.hc.client5.http.impl.classic.CloseableHttpResponse;
  import org.apache.hc.client5.http.impl.classic.HttpClients;
  import org.apache.hc.client5.http.protocol.HttpClientContext;
  import org.apache.hc.core5.http.HttpHost;
  import org.apache.hc.core5.http.io.entity.EntityUtils;
  
  /**
   * An example of how HttpClient can authenticate multiple requests
   * using the same Digest scheme. After the initial request / response exchange
   * all subsequent requests sharing the same execution context can re-use
   * the last Digest nonce value to authenticate with the server.
   */
  public class ClientPreemptiveDigestAuthentication {
  
      public static void main(final String[] args) throws Exception {
          try (final CloseableHttpClient httpclient = HttpClients.createDefault()) {
  
              final HttpHost target = new HttpHost("http", "httpbin.org", 80);
  
              final HttpClientContext localContext = HttpClientContext.create();
              final BasicCredentialsProvider credentialsProvider = new BasicCredentialsProvider();
              credentialsProvider.setCredentials(
                      new AuthScope(target),
                      new UsernamePasswordCredentials("user", "passwd".toCharArray()));
              localContext.setCredentialsProvider(credentialsProvider);
  
              final HttpGet httpget = new HttpGet("http://httpbin.org/digest-auth/auth/user/passwd");
  
              System.out.println("Executing request " + httpget.getMethod() + " " + httpget.getUri());
              for (int i = 0; i < 3; i++) {
                  try (final CloseableHttpResponse response = httpclient.execute(target, httpget, localContext)) {
                      System.out.println("----------------------------------------");
                      System.out.println(response.getCode() + " " + response.getReasonPhrase());
                      EntityUtils.consume(response.getEntity());
  
                      final AuthExchange authExchange = localContext.getAuthExchange(target);
                      if (authExchange != null) {
                          final AuthScheme authScheme = authExchange.getAuthScheme();
                          if (authScheme instanceof DigestScheme) {
                              final DigestScheme digestScheme = (DigestScheme) authScheme;
                              System.out.println("Nonce: " + digestScheme.getNonce() +
                                      "; count: " + digestScheme.getNounceCount());
                          }
                      }
                  }
              }
          }
      }
  
  }