/* 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.runas;

 import org.acegisecurity.Authentication;

 import org.acegisecurity.ConfigAttribute;

 import org.acegisecurity.ConfigAttributeDefinition;

 import org.acegisecurity.GrantedAuthority;

 import org.acegisecurity.GrantedAuthorityImpl;

 import org.acegisecurity.RunAsManager;

 import org.springframework.beans.factory.InitializingBean;

 import org.springframework.util.Assert;

 import java.util.Iterator;

 import java.util.List;

 import java.util.Vector;

 /**

  * Basic concrete implementation of a {@link RunAsManager}.<p>Is activated if any {@link

  * ConfigAttribute#getAttribute()} is prefixed  with <Code>RUN_AS_</code>. If found, it generates a new {@link

  * RunAsUserToken} containing the same principal, credentials and granted authorities as the original {@link

  * Authentication} object, along with {@link GrantedAuthorityImpl}s for each <code>RUN_AS_</code> indicated. The

  * created <code>GrantedAuthorityImpl</code>s will be prefixed with a special prefix indicating that it is a role

  * (default prefix value is <code>ROLE_</code>), and then the remainder of the <code>RUN_AS_</code> keyword. For

  * example, <code>RUN_AS_FOO</code> will result in the creation of a granted authority of

  * <code>ROLE_RUN_AS_FOO</code>.</p>

  *  <p>The role prefix may be overriden from the default, to match that used elsewhere, for example when using an

  * existing role database with another prefix. An empty role prefix may also be specified. Note however that there are

  * potential issues with using an empty role prefix since different categories of  {@link

  * org.acegisecurity.ConfigAttribute} can not be properly discerned based on the prefix, with possible consequences

  * when performing voting and other actions. However, this option may be of some use when using preexisting role names

  * without a prefix, and no ability exists to prefix them with a role prefix on reading them in, such as provided for

  * example in  {@link org.acegisecurity.userdetails.jdbc.JdbcDaoImpl}.</p>

  *

  * @author Ben Alex

  * @author colin sampaleanu

  * @version $Id: RunAsManagerImpl.java 1496 2006-05-23 13:38:33Z benalex $

  */

 public class RunAsManagerImpl implements RunAsManager, InitializingBean {

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

     private String key;

     private String rolePrefix = "ROLE_";

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

     public void afterPropertiesSet() throws Exception {

         Assert.notNull(key, "A Key is required and should match that configured for the RunAsImplAuthenticationProvider");

     }

     public Authentication buildRunAs(Authentication authentication, Object object, ConfigAttributeDefinition config) {

         List newAuthorities = new Vector();

         Iterator iter = config.getConfigAttributes();

         while (iter.hasNext()) {

             ConfigAttribute attribute = (ConfigAttribute) iter.next();

             if (this.supports(attribute)) {

                 GrantedAuthorityImpl extraAuthority = new GrantedAuthorityImpl(getRolePrefix()

                         + attribute.getAttribute());

                 newAuthorities.add(extraAuthority);

             }

         }

         if (newAuthorities.size() == 0) {

             return null;

         } else {

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

                 newAuthorities.add(authentication.getAuthorities()[i]);

             }

             GrantedAuthority[] resultType = {new GrantedAuthorityImpl("holder")};

             GrantedAuthority[] newAuthoritiesAsArray = (GrantedAuthority[]) newAuthorities.toArray(resultType);

             return new RunAsUserToken(this.key, authentication.getPrincipal(), authentication.getCredentials(),

                 newAuthoritiesAsArray, authentication.getClass());

         }

     }

     public String getKey() {

         return key;

     }

     public String getRolePrefix() {

         return rolePrefix;

     }

     public void setKey(String key) {

         this.key = key;

     }

     /**

      * Allows the default role prefix of <code>ROLE_</code> to be overriden. May be set to an empty value,

      * although this is usually not desireable.

      *

      * @param rolePrefix the new prefix

      */

     public void setRolePrefix(String rolePrefix) {

         this.rolePrefix = rolePrefix;

     }

     public boolean supports(ConfigAttribute attribute) {

         if ((attribute.getAttribute() != null) && attribute.getAttribute().startsWith("RUN_AS_")) {

             return true;

         } else {

             return false;

         }

     }

     /**

      * This implementation supports any type of class, because it does not query the presented secure object.

      *

      * @param clazz the secure object

      *

      * @return alwaus <code>true</code>

      */

     public boolean supports(Class clazz) {

         return true;

     }

 }