/*
    * Copyright (c) 2002-2014, Mairie de Paris
    * All rights reserved.
    *
    * Redistribution and use in source and binary forms, with or without
    * modification, are permitted provided that the following conditions
    * are met:
    *
    *  1. Redistributions of source code must retain the above copyright notice
   *     and the following disclaimer.
   *
   *  2. Redistributions in binary form must reproduce the above copyright notice
   *     and the following disclaimer in the documentation and/or other materials
   *     provided with the distribution.
   *
   *  3. Neither the name of 'Mairie de Paris' nor 'Lutece' nor the names of its
   *     contributors may be used to endorse or promote products derived from
   *     this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   * POSSIBILITY OF SUCH DAMAGE.
   *
   * License 1.0
   */
  package fr.paris.lutece.portal.service.security;
  
  import fr.paris.lutece.portal.service.spring.SpringContextService;
  
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.Map;
  import java.util.Set;
  import java.util.UUID;
  
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpSession;
  
  
  /**
   *
   * This class provides a security service for getting and verify tokens
   *
   */
  public class SecurityTokenService implements ISecurityTokenService
  {
      public static final String MARK_TOKEN = "token";
      public static final String PARAMETER_TOKEN = "token";
      private static final String BEAN_SECURITY_TOKEN_SERVICE = "securityTokenService";
      private static final String PARAMETER_SESSION_TOKENS = "tokens";
      private static ISecurityTokenService _singleton;
  
      /**
       * SecurityTokenService
       */
      private SecurityTokenService(  )
      {
      }
  
      /**
       * Returns the instance of the singleton
       *
       * @return The instance of the singleton
       */
      public static ISecurityTokenService getInstance(  )
      {
          if ( _singleton == null )
          {
              _singleton = SpringContextService.getBean( BEAN_SECURITY_TOKEN_SERVICE );
          }
  
          return _singleton;
      }
  
      /**
       * {@inheritDoc}
       */
      @Override
      public String getToken( HttpServletRequest request, String strAction )
      {
          String strToken = generateNewKey(  );
          HttpSession session = request.getSession( true );
          Map<String, Set<String>> hashTokens;
  
          if ( session.getAttribute( PARAMETER_SESSION_TOKENS ) == null )
          {
              hashTokens = new HashMap<String, Set<String>>(  );
              session.setAttribute( PARAMETER_SESSION_TOKENS, hashTokens );
          }
  
          hashTokens = (Map<String, Set<String>>) session.getAttribute( PARAMETER_SESSION_TOKENS );
 
         if ( !hashTokens.containsKey( strAction ) )
         {
             hashTokens.put( strAction, new HashSet<String>(  ) );
         }
 
         hashTokens.get( strAction ).add( strToken );
 
         return strToken;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public boolean validate( HttpServletRequest request, String StrAction )
     {
         HttpSession session = request.getSession( true );
 
         String strToken = request.getParameter( PARAMETER_TOKEN );
 
         if ( ( session.getAttribute( PARAMETER_SESSION_TOKENS ) != null ) &&
                 ( (Map<String, Set<String>>) session.getAttribute( PARAMETER_SESSION_TOKENS ) ).containsKey( StrAction ) &&
                 ( (Map<String, Set<String>>) session.getAttribute( PARAMETER_SESSION_TOKENS ) ).get( StrAction )
                       .contains( strToken ) )
         {
             ( (Map<String, Set<String>>) session.getAttribute( PARAMETER_SESSION_TOKENS ) ).get( StrAction )
               .remove( strToken );
 
             return true;
         }
 
         return false;
     }
 
     /**
      * Generate a new key
      *
      * @return a new key
      */
     private String generateNewKey(  )
     {
         UUID key = UUID.randomUUID(  );
 
         return key.toString(  );
     }
 }