/*
 * Copyright 2009 SIB Visions GmbH
 * 
 * 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.
 *
 *
 * History
 *
 * 28.09.2009 - [JR] - creation
 */
package apps.firstapp.security;

import java.util.Hashtable;

import javax.rad.remote.IConnectionConstants;
import javax.rad.server.ISession;

import com.sibvisions.rad.server.security.ISecurityManager;

/**
 * The <code>HashtableSecurityManager</code> is a {@link Hashtable} 
 * based {@link ISecurityManager} implementation.
 *  
 * @author René Jahn
 */
public class HashtableSecurityManager implements ISecurityManager
{
   //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   // Class members
   //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

   /** contains username/password mapping. */
   private Hashtable<String, String> htUsers = new Hashtable<String, String>();
   
   //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   // Initialization
   //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

   /**
    * Creates a new instance of <code>HashtableSecurityManager</code> with
    * predefined users.
    */
   public HashtableSecurityManager()
   {
      htUsers.put("username", "password");
      htUsers.put("jvx", "jvx");
   }
   
   //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   // Interface implementation
   //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

   /**
    * {@inheritDoc}
    */
   public synchronized void validateAuthentication(ISession pSession)
   {
      checkUser(pSession);
   }

   /**
    * {@inheritDoc}
    */
   public synchronized void changePassword(ISession pSession)
   {
      checkUser(pSession);
      
      //check old password with current password!
      if (!htUsers.get(pSession.getUserName()).equals(
                       pSession.getProperty(IConnectionConstants.OLDPASSWORD)))
      {
         throw new SecurityException("Invalid password");
      }

      //user is valid -> change the password
      htUsers.put(pSession.getUserName(), 
                  (String)pSession.getProperty(IConnectionConstants.NEWPASSWORD));
   }
   
   /**
    * {@inheritDoc}
    */
   public synchronized void logout(ISession pSession)
   {
   }

   /**
    * {@inheritDoc}
    */
   public synchronized IAccessController getAccessController(ISession pSession)
   {
      return null;
   }

   /**
    * {@inheritDoc}
    */
   public synchronized void release()
   {
   }

   //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   // User-defined methods
   //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

   /**
    * Checks if the user is known and the password is valid.
    * 
    * @param pSession the session to authenticate
    */
   private void checkUser(ISession pSession)
   {
      String sPwd = htUsers.get(pSession.getUserName());
      
      if (sPwd == null)
      {
         throw new SecurityException("User not found!");
      }
      
      if (!sPwd.equals(pSession.getPassword()))
      {
         throw new SecurityException("Invalid password");
      }
   }

}   // HashtableSecurityManager