/**
    * This file Copyright (c) 2003-2011 Magnolia International
    * Ltd.  (http://www.magnolia-cms.com). All rights reserved.
    *
    *
    * This file is dual-licensed under both the Magnolia
    * Network Agreement and the GNU General Public License.
    * You may elect to use one or the other of these licenses.
    *
   * This file is distributed in the hope that it will be
   * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
   * implied warranty of MERCHANTABILITY or FITNESS FOR A
   * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
   * Redistribution, except as permitted by whichever of the GPL
   * or MNA you select, is prohibited.
   *
   * 1. For the GPL license (GPL), you can redistribute and/or
   * modify this file under the terms of the GNU General
   * Public License, Version 3, as published by the Free Software
   * Foundation.  You should have received a copy of the GNU
   * General Public License, Version 3 along with this program;
   * if not, write to the Free Software Foundation, Inc., 51
   * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * 2. For the Magnolia Network Agreement (MNA), this file
   * and the accompanying materials are made available under the
   * terms of the MNA which accompanies this distribution, and
   * is available at http://www.magnolia-cms.com/mna.html
   *
   * Any modifications to this file must keep this entire header
   * intact.
   *
   */
  package info.magnolia.cms.security;
  
  import java.security.Principal;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.HashSet;
  import java.util.List;
  import javax.security.auth.Subject;
  
  import info.magnolia.cms.security.auth.ACL;
  import info.magnolia.cms.security.auth.PrincipalCollectionImpl;
  
  /**
   * Get the current role or user manager.
   * @author philipp
   * @version $Revision$ ($Author$)
   */
  public class Security {
  
      /**
       * Returns the configured RoleManager.
       */
      public static RoleManager getRoleManager() {
          return getSecuritySupport().getRoleManager();
      }
  
      /**
       * Returns the configured UserManager.
       */
      public static UserManager getUserManager() {
          return getSecuritySupport().getUserManager();
      }
  
      /**
       * Returns the configured GroupManager.
       */
      public static GroupManager getGroupManager() {
          return getSecuritySupport().getGroupManager();
      }
  
      public static SecuritySupport getSecuritySupport() {
          return SecuritySupport.Factory.getInstance();
      }
  
      public static User getAnonymousUser() {
          return getSecuritySupport().getUserManager(Realm.REALM_SYSTEM.getName()).getAnonymousUser();
      }
  
      public static User getSystemUser() {
          return getSecuritySupport().getUserManager(Realm.REALM_SYSTEM.getName()).getSystemUser();
      }
  
      public static Subject getSystemSubject() {
          return createSubjectAndPopulate(Security.getSystemUser());
      }
  
      public static Subject getAnonymousSubject() {
          return createSubjectAndPopulate(Security.getAnonymousUser());
      }
  
      private static Subject createSubjectAndPopulate(User user) {
  
          RoleManager roleManager = getRoleManager();
  
          List<Principal> acls = new ArrayList<Principal>();
          for (String role : user.getAllRoles()) {
             acls.addAll(roleManager.getACLs(role).values());
         }
 
         PrincipalCollectionImpl principalCollection = new PrincipalCollectionImpl();
         mergePrincipals(principalCollection, acls);
 
         Subject subject = new Subject();
         subject.getPrincipals().add(user);
         subject.getPrincipals().add(principalCollection);
         return subject;
     }
 
     private static void mergePrincipals(PrincipalCollectionImpl principalCollection, List<Principal> acls) {
         for (Principal principal : acls) {
             ACL princ = (ACL) principal;
             if (principalCollection.contains(princ.getName())) {
                 ACL oldACL = (ACL) principalCollection.get(princ.getName());
                 Collection<Permission> permissions = new HashSet<Permission>(oldACL.getList());
                 permissions.addAll(princ.getList());
                 principalCollection.remove(oldACL);
                 princ = new ACLImpl(princ.getName(), new ArrayList<Permission>(permissions));
             }
             principalCollection.add(princ);
         }
     }
 }