content: /*
   * 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.
   */
  package org.apache.camel.component.http.handler;
  
  import java.io.IOException;
  import java.nio.charset.StandardCharsets;
  import java.util.HashMap;
  import java.util.Map;
  
  import org.apache.camel.component.http.HttpCredentialsHelper;
  import org.apache.camel.util.json.Jsoner;
  import org.apache.hc.core5.http.ClassicHttpRequest;
  import org.apache.hc.core5.http.ClassicHttpResponse;
  import org.apache.hc.core5.http.ContentType;
  import org.apache.hc.core5.http.HttpException;
  import org.apache.hc.core5.http.HttpHeaders;
  import org.apache.hc.core5.http.io.HttpRequestHandler;
  import org.apache.hc.core5.http.io.entity.EntityUtils;
  import org.apache.hc.core5.http.io.entity.StringEntity;
  import org.apache.hc.core5.http.protocol.HttpContext;
  import org.apache.hc.core5.net.WWWFormCodec;
  
  public class OAuth2ScopeRequestHandler implements HttpRequestHandler {
  
      private final String clientId;
      private final String clientSecret;
      private final String expectedToken;
      private final String scope;
  
      public OAuth2ScopeRequestHandler(String expectedToken, String clientId, String clientSecret, String scope) {
          this.expectedToken = expectedToken;
          this.clientId = clientId;
          this.clientSecret = clientSecret;
          this.scope = scope;
      }
  
      @Override
      public void handle(ClassicHttpRequest request, ClassicHttpResponse response, HttpContext context)
              throws HttpException, IOException {
          String requestBody = EntityUtils.toString(request.getEntity());
          WWWFormCodec.parse(requestBody, StandardCharsets.UTF_8).stream()
                  .filter(pair -> pair.getName().equals("scope") && pair.getValue().equals(scope))
                  .findAny().orElseThrow(() -> new HttpException("Invalid or missing scope"));
  
          if (request.getHeader(HttpHeaders.AUTHORIZATION) == null || !request.getHeader(HttpHeaders.AUTHORIZATION).getValue()
                  .equals(HttpCredentialsHelper.generateBasicAuthHeader(clientId, clientSecret)))
              throw new HttpException("Invalid credentials");
  
          Map<String, String> responseEntity = new HashMap<>();
          responseEntity.put("access_token", expectedToken);
  
          response.setEntity(new StringEntity(Jsoner.serialize(responseEntity), ContentType.APPLICATION_JSON));
      }
  
  }
  