/*
    * 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.commons.vfs2.provider;
  
  import java.io.IOException;
  import java.net.URL;
  import java.net.URLConnection;
  import java.net.URLStreamHandler;
  
  import org.apache.commons.io.function.Uncheck;
  import org.apache.commons.vfs2.FileObject;
  import org.apache.commons.vfs2.FileSystemOptions;
  
  /**
   * A default URL stream handler that will work for most file systems.
   */
  public class DefaultURLStreamHandler extends URLStreamHandler {
  
      private final VfsComponentContext context;
      private final FileSystemOptions fileSystemOptions;
  
      /**
       * Constructs a new instance.
       *
       * @param context VFS component context.
       */
      public DefaultURLStreamHandler(final VfsComponentContext context) {
          this(context, null);
      }
  
      /**
       * Constructs a new instance.
       *
       * @param context VFS component context.
       * @param fileSystemOptions FileSystemOptions to resolve files.
       */
      public DefaultURLStreamHandler(final VfsComponentContext context, final FileSystemOptions fileSystemOptions) {
          this.context = context;
          this.fileSystemOptions = fileSystemOptions;
      }
  
      @Override
      protected URLConnection openConnection(final URL url) throws IOException {
          final FileObject entry = context.resolveFile(url.toExternalForm(), fileSystemOptions);
          return new DefaultURLConnection(url, entry.getContent());
      }
  
      @Override
      protected void parseURL(final URL u, final String spec, final int start, final int limit) {
          Uncheck.run(() -> {
              final FileObject old = context.resolveFile(u.toExternalForm(), fileSystemOptions);
  
              final FileObject newURL;
              if (start > 0 && spec.charAt(start - 1) == ':') {
                  newURL = context.resolveFile(old, spec, fileSystemOptions);
              } else if (old.isFile() && old.getParent() != null) {
                  // for files we have to resolve relative
                  newURL = old.getParent().resolveFile(spec);
              } else {
                  newURL = old.resolveFile(spec);
              }
  
              final String url = newURL.getName().getURI();
              final StringBuilder filePart = new StringBuilder();
              final String protocolPart = UriParser.extractScheme(context.getFileSystemManager().getSchemes(), url, filePart);
  
              setURL(u, protocolPart, "", -1, null, null, filePart.toString(), null, null);
          });
      }
  
      @Override
      protected String toExternalForm(final URL u) {
          return u.getProtocol() + ":" + u.getFile();
      }
  }