/* Copyright 2004, 2005, 2006 Acegi Technology Pty Limited

  *

  * Licensed 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.acegisecurity.wrapper;

 import org.acegisecurity.Authentication;

 import org.acegisecurity.AuthenticationTrustResolver;

 import org.acegisecurity.AuthenticationTrustResolverImpl;

 import org.acegisecurity.context.SecurityContextHolder;

 import org.acegisecurity.userdetails.UserDetails;

 import org.acegisecurity.util.PortResolver;

 import java.security.Principal;

 import javax.servlet.http.HttpServletRequest;

 import javax.servlet.http.HttpServletRequestWrapper;

 /**

  * An Acegi Security-aware <code>HttpServletRequestWrapper</code>, which uses the

  * <code>SecurityContext</code>-defined <code>Authentication</code> object for {@link

  * SecurityContextHolderAwareRequestWrapper#isUserInRole(java.lang.String)} and {@link

  * javax.servlet.http.HttpServletRequestWrapper#getRemoteUser()} responses.

  *

  * @author Orlando Garcia Carmona

  * @author Ben Alex

  * @version $Id: SecurityContextHolderAwareRequestWrapper.java 1859 2007-05-24 23:20:40Z vishalpuri $

  */

 public class SecurityContextHolderAwareRequestWrapper extends HttpServletRequestWrapper {

     //~ Instance fields ================================================================================================

     private AuthenticationTrustResolver authenticationTrustResolver = new AuthenticationTrustResolverImpl();

     //~ Constructors ===================================================================================================

     public SecurityContextHolderAwareRequestWrapper(HttpServletRequest request, PortResolver portResolver) {

         super(request);

     }

     //~ Methods ========================================================================================================

     /**

      * Obtain the current active <code>Authentication</code>

      *

      * @return the authentication object or <code>null</code>

      */

     private Authentication getAuthentication() {

         Authentication auth = SecurityContextHolder.getContext().getAuthentication();

         if (!authenticationTrustResolver.isAnonymous(auth)) {

             return auth;

         }

         return null;

     }

     /**

      * Returns the principal's name, as obtained from the <code>SecurityContextHolder</code>. Properly handles

      * both <code>String</code>-based and <code>UserDetails</code>-based principals.

      *

      * @return the username or <code>null</code> if unavailable

      */

     public String getRemoteUser() {

         Authentication auth = getAuthentication();

         if ((auth == null) || (auth.getPrincipal() == null)) {

             return null;

         }

         if (auth.getPrincipal() instanceof UserDetails) {

             return ((UserDetails) auth.getPrincipal()).getUsername();

         }

         return auth.getPrincipal().toString();

     }

     /**

      * Returns the <code>Authentication</code> (which is a subclass of <code>Principal</code>), or

      * <code>null</code> if unavailable.

      *

      * @return the <code>Authentication</code>, or <code>null</code>

      */

     public Principal getUserPrincipal() {

         Authentication auth = getAuthentication();

         if ((auth == null) || (auth.getPrincipal() == null)) {

             return null;

         }

         return auth;

     }

     private boolean isGranted(String role) {

         Authentication auth = getAuthentication();

         if ((auth == null) || (auth.getPrincipal() == null) || (auth.getAuthorities() == null)) {

             return false;

         }

         for (int i = 0; i < auth.getAuthorities().length; i++) {

             if (role.equals(auth.getAuthorities()[i].getAuthority())) {

                 return true;

             }

         }

         return false;

     }

     /**

      * Simple searches for an exactly matching {@link org.acegisecurity.GrantedAuthority#getAuthority()}.<p>Will

      * always return <code>false</code> if the <code>SecurityContextHolder</code> contains an

      * <code>Authentication</code> with <code>null</code><code>principal</code> and/or <code>GrantedAuthority[]</code>

      * objects.</p>

      *

      * @param role the <code>GrantedAuthority</code><code>String</code> representation to check for

      *

      * @return <code>true</code> if an <b>exact</b> (case sensitive) matching granted authority is located,

      *         <code>false</code> otherwise

      */

     public boolean isUserInRole(String role) {

         return isGranted(role);

     }

 }