/*
    * ====================================================================
    * 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.testing.classic;
  
  import java.io.IOException;
  import java.net.URI;
  import java.net.URISyntaxException;
  
  import org.apache.hc.client5.testing.redirect.Redirect;
  import org.apache.hc.client5.testing.redirect.RedirectResolver;
  import org.apache.hc.core5.http.ClassicHttpRequest;
  import org.apache.hc.core5.http.ClassicHttpResponse;
  import org.apache.hc.core5.http.HeaderElements;
  import org.apache.hc.core5.http.HttpException;
  import org.apache.hc.core5.http.HttpHeaders;
  import org.apache.hc.core5.http.ProtocolException;
  import org.apache.hc.core5.http.io.HttpServerRequestHandler;
  import org.apache.hc.core5.http.message.BasicClassicHttpResponse;
  import org.apache.hc.core5.http.message.BasicHeader;
  import org.apache.hc.core5.http.protocol.HttpContext;
  import org.apache.hc.core5.util.Args;
  
  public class RedirectingDecorator implements HttpServerRequestHandler {
  
      private final HttpServerRequestHandler requestHandler;
      private final RedirectResolver redirectResolver;
  
      public RedirectingDecorator(final HttpServerRequestHandler requestHandler,
                                  final RedirectResolver redirectResolver) {
          this.requestHandler = Args.notNull(requestHandler, "Request handler");
          this.redirectResolver = redirectResolver;
      }
  
      @Override
      public void handle(final ClassicHttpRequest request,
                         final ResponseTrigger responseTrigger,
                         final HttpContext context) throws HttpException, IOException {
          try {
              final URI requestURI = request.getUri();
              final Redirect redirect = redirectResolver != null ? redirectResolver.resolve(requestURI) : null;
              if (redirect != null) {
                  final ClassicHttpResponse response = new BasicClassicHttpResponse(redirect.status);
                  if (redirect.location != null) {
                      response.addHeader(new BasicHeader(HttpHeaders.LOCATION, redirect.location));
                  }
                  switch (redirect.connControl) {
                      case KEEP_ALIVE:
                          response.addHeader(new BasicHeader(HttpHeaders.CONNECTION, HeaderElements.KEEP_ALIVE));
                          break;
                      case CLOSE:
                          response.addHeader(new BasicHeader(HttpHeaders.CONNECTION, HeaderElements.CLOSE));
                  }
                  responseTrigger.submitResponse(response);
              } else {
                  requestHandler.handle(request, responseTrigger, context);
              }
          } catch (final URISyntaxException ex) {
              throw new ProtocolException(ex.getMessage(), ex);
          }
      }
  }