content: /*
   * Copyright (C) 2013 Glyptodon LLC
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy
   * of this software and associated documentation files (the "Software"), to deal
   * in the Software without restriction, including without limitation the rights
   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in
   * all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
   * THE SOFTWARE.
   */
  
  package org.glyptodon.guacamole.net.basic.crud.permissions;
  
  import java.io.IOException;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  import javax.xml.stream.XMLOutputFactory;
  import javax.xml.stream.XMLStreamException;
  import javax.xml.stream.XMLStreamWriter;
  import org.glyptodon.guacamole.GuacamoleClientException;
  import org.glyptodon.guacamole.GuacamoleException;
  import org.glyptodon.guacamole.GuacamoleSecurityException;
  import org.glyptodon.guacamole.GuacamoleServerException;
  import org.glyptodon.guacamole.net.auth.Directory;
  import org.glyptodon.guacamole.net.auth.User;
  import org.glyptodon.guacamole.net.auth.UserContext;
  import org.glyptodon.guacamole.net.auth.permission.ConnectionGroupPermission;
  import org.glyptodon.guacamole.net.auth.permission.ConnectionPermission;
  import org.glyptodon.guacamole.net.auth.permission.ObjectPermission;
  import org.glyptodon.guacamole.net.auth.permission.Permission;
  import org.glyptodon.guacamole.net.auth.permission.SystemPermission;
  import org.glyptodon.guacamole.net.auth.permission.UserPermission;
  import org.glyptodon.guacamole.net.basic.AuthenticatingHttpServlet;
  
  /**
   * Simple HttpServlet which outputs XML containing a list of all visible
   * permissions of a given user.
   *
   * @author Michael Jumper
   */
  public class List extends AuthenticatingHttpServlet {
  
      /**
       * Returns the XML attribute value representation of the given
       * SystemPermission.Type.
       *
       * @param type The SystemPermission.Type to translate into a String.
       * @return The XML attribute value representation of the given
       *         SystemPermission.Type.
       *
       * @throws GuacamoleException If the type given is not implemented.
       */
      private String toString(SystemPermission.Type type)
          throws GuacamoleException {
  
          switch (type) {
              case CREATE_USER:             return "create-user";
              case CREATE_CONNECTION:       return "create-connection";
              case CREATE_CONNECTION_GROUP: return "create-connection-group";
              case ADMINISTER:              return "admin";
          }
  
          throw new GuacamoleException("Unknown permission type: " + type);
  
      }
  
      /**
       * Returns the XML attribute value representation of the given
       * ObjectPermission.Type.
       *
       * @param type The ObjectPermission.Type to translate into a String.
       * @return The XML attribute value representation of the given
       *         ObjectPermission.Type.
       *
       * @throws GuacamoleException If the type given is not implemented.
       */
      private String toString(ObjectPermission.Type type)
          throws GuacamoleException {
  
          switch (type) {
              case READ:       return "read";
              case UPDATE:     return "update";
              case DELETE:     return "delete";
              case ADMINISTER: return "admin";
          }
  
          throw new GuacamoleException("Unknown permission type: " + type);
  
      }
  
      @Override
      protected void authenticatedService(
              UserContext context,
              HttpServletRequest request, HttpServletResponse response)
      throws GuacamoleException {
  
          // Do not cache
          response.setHeader("Cache-Control", "no-cache");
          
          // Set encoding
          response.setCharacterEncoding("UTF-8");
  
          // Write actual XML
          try {
  
              User user;
  
              // Get username
              String username = request.getParameter("user");
              if (username != null) {
  
                  // Get user directory
                  Directory<String, User> users = context.getUserDirectory();
  
                  // Get specific user
                  user = users.get(username);
              }
              else
                  user = context.self();
              
              if (user == null)
                  throw new GuacamoleSecurityException("No such user.");
  
              // Write XML content type
              response.setHeader("Content-Type", "text/xml");
  
              XMLOutputFactory outputFactory = XMLOutputFactory.newInstance();
              XMLStreamWriter xml = outputFactory.createXMLStreamWriter(response.getWriter());
  
              // Begin document
              xml.writeStartDocument();
              xml.writeStartElement("permissions");
              xml.writeAttribute("user", user.getUsername());
  
              // For each entry, write corresponding user element
              for (Permission permission : user.getPermissions()) {
  
                  // System permission
                  if (permission instanceof SystemPermission) {
  
                      // Get permission
                      SystemPermission sp = (SystemPermission) permission;
  
                      // Write permission
                      xml.writeEmptyElement("system");
                      xml.writeAttribute("type", toString(sp.getType()));
  
                  }
  
                  // Config permission
                  else if (permission instanceof ConnectionPermission) {
  
                      // Get permission
                      ConnectionPermission cp =
                              (ConnectionPermission) permission;
  
                      // Write permission
                      xml.writeEmptyElement("connection");
                      xml.writeAttribute("type", toString(cp.getType()));
                      xml.writeAttribute("name", cp.getObjectIdentifier());
  
                  }
  
                  // Connection group permission
                  else if (permission instanceof ConnectionGroupPermission) {
  
                      // Get permission
                      ConnectionGroupPermission cgp =
                              (ConnectionGroupPermission) permission;
  
                      // Write permission
                      xml.writeEmptyElement("connection-group");
                      xml.writeAttribute("type", toString(cgp.getType()));
                      xml.writeAttribute("name", cgp.getObjectIdentifier());
  
                  }
  
                  // User permission
                  else if (permission instanceof UserPermission) {
  
                      // Get permission
                      UserPermission up = (UserPermission) permission;
  
                      // Write permission
                      xml.writeEmptyElement("user");
                      xml.writeAttribute("type", toString(up.getType()));
                      xml.writeAttribute("name", up.getObjectIdentifier());
  
                  }
  
                  else
                      throw new GuacamoleClientException(
                              "Unsupported permission type.");
  
              }
  
              // End document
              xml.writeEndElement();
              xml.writeEndDocument();
  
          }
          catch (XMLStreamException e) {
              throw new GuacamoleServerException(
                      "Unable to write permission list XML.", e);
          }
          catch (IOException e) {
              throw new GuacamoleServerException(
                      "I/O error writing permission list XML.", e);
          }
  
      }
  
  }
  