/*
    * 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.maven.search.backend.smo.internal;
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.net.HttpURLConnection;
  import java.net.URL;
  import java.nio.charset.StandardCharsets;
  import java.util.Map;
  import java.util.Scanner;
  
  import org.apache.maven.search.backend.smo.SmoSearchTransport;
  
  /**
   * {@link java.net.HttpURLConnection} backed transport.
   */
  public class UrlConnectionSmoSearchTransport implements SmoSearchTransport {
      @Override
      public String fetch(String serviceUri, Map<String, String> headers) throws IOException {
          HttpURLConnection httpConnection = (HttpURLConnection) new URL(serviceUri).openConnection();
          httpConnection.setInstanceFollowRedirects(false);
          for (Map.Entry<String, String> entry : headers.entrySet()) {
              httpConnection.setRequestProperty(entry.getKey(), entry.getValue());
          }
          int httpCode = httpConnection.getResponseCode();
          if (httpCode == HttpURLConnection.HTTP_OK) {
              try (InputStream inputStream = httpConnection.getInputStream()) {
                  try (Scanner scanner = new Scanner(inputStream, StandardCharsets.UTF_8.name())) {
                      return scanner.useDelimiter("\\A").next();
                  }
              }
          } else {
              throw new IOException("Unexpected response code: " + httpCode);
          }
      }
  }