/*
    * 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.eclipse.aether.transport.http;
  
  import java.net.URI;
  import java.net.URISyntaxException;
  import java.util.ArrayList;
  import java.util.List;
  
  import org.apache.http.client.utils.URIUtils;
  
  /**
   * Helps to deal with URIs.
   */
  final class UriUtils {
  
      public static URI resolve(URI base, URI ref) {
          String path = ref.getRawPath();
          if (path != null && path.length() > 0) {
              path = base.getRawPath();
              if (path == null || !path.endsWith("/")) {
                  try {
                      base = new URI(base.getScheme(), base.getAuthority(), base.getPath() + '/', null, null);
                  } catch (URISyntaxException e) {
                      throw new IllegalStateException(e);
                  }
              }
          }
          return URIUtils.resolve(base, ref);
      }
  
      public static List<URI> getDirectories(URI base, URI uri) {
          List<URI> dirs = new ArrayList<>();
          for (URI dir = uri.resolve("."); !isBase(base, dir); dir = dir.resolve("..")) {
              dirs.add(dir);
          }
          return dirs;
      }
  
      private static boolean isBase(URI base, URI uri) {
          String path = uri.getRawPath();
          if (path == null || "/".equals(path)) {
              return true;
          }
          if (base != null) {
              URI rel = base.relativize(uri);
              if (rel.getRawPath() == null || rel.getRawPath().isEmpty() || rel.equals(uri)) {
                  return true;
              }
          }
          return false;
      }
  }