/* 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.ldap.search;
  
  import org.acegisecurity.ldap.InitialDirContextFactory;
  import org.acegisecurity.ldap.LdapTemplate;
  import org.acegisecurity.ldap.LdapUserSearch;
  
  import org.acegisecurity.userdetails.UsernameNotFoundException;
  import org.acegisecurity.userdetails.ldap.LdapUserDetails;
  import org.acegisecurity.userdetails.ldap.LdapUserDetailsImpl;
  import org.acegisecurity.userdetails.ldap.LdapUserDetailsMapper;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  
  import org.springframework.dao.IncorrectResultSizeDataAccessException;
  
  import org.springframework.util.Assert;
  
  import javax.naming.directory.DirContext;
  import javax.naming.directory.SearchControls;
  
  
  /**
   * LdapUserSearch implementation which uses an Ldap filter to locate the user.
   *
   * @author Robert Sanders
   * @author Luke Taylor
   * @version $Id: FilterBasedLdapUserSearch.java 2626 2008-02-14 18:58:08Z luke_t $
   *
   * @see SearchControls
   */
  public class FilterBasedLdapUserSearch implements LdapUserSearch {
      //~ Static fields/initializers =====================================================================================
  
      private static final Log logger = LogFactory.getLog(FilterBasedLdapUserSearch.class);
  
      //~ Instance fields ================================================================================================
  
      private InitialDirContextFactory initialDirContextFactory;
      private LdapUserDetailsMapper userDetailsMapper = new LdapUserDetailsMapper();
  
      /**
       * The LDAP SearchControls object used for the search. Shared between searches so shouldn't be modified
       * once the bean has been configured.
       */
      private SearchControls searchControls = new SearchControls();
  
      /** Context name to search in, relative to the root DN of the configured InitialDirContextFactory. */
      private String searchBase = "";
  
      /**
       * The filter expression used in the user search. This is an LDAP search filter (as defined in 'RFC 2254')
       * with optional arguments. See the documentation for the <tt>search</tt> methods in {@link
       * javax.naming.directory.DirContext DirContext} for more information.<p>In this case, the username is the
       * only parameter.</p>
       *  Possible examples are:
       *  <ul>
       *      <li>(uid={0}) - this would search for a username match on the uid attribute.</li>
       *  </ul>
       *  TODO: more examples.
       */
      private String searchFilter;
  
      //~ Constructors ===================================================================================================
  
      public FilterBasedLdapUserSearch(String searchBase, String searchFilter,
              InitialDirContextFactory initialDirContextFactory) {
          Assert.notNull(initialDirContextFactory, "initialDirContextFactory must not be null");
          Assert.notNull(searchFilter, "searchFilter must not be null.");
          Assert.notNull(searchBase, "searchBase must not be null (an empty string is acceptable).");
  
          this.searchFilter = searchFilter;
          this.initialDirContextFactory = initialDirContextFactory;
          this.searchBase = searchBase;
  
          if (searchBase.length() == 0) {
              logger.info("SearchBase not set. Searches will be performed from the root: "
                  + initialDirContextFactory.getRootDn());
          }
      }
  
      //~ Methods ========================================================================================================
  
      /**
      * Return the LdapUserDetails containing the user's information
      *
      * @param username the username to search for.
      *
      * @return An LdapUserDetails object containing the details of the located user's directory entry
      *
      * @throws UsernameNotFoundException if no matching entry is found.
      */
     public LdapUserDetails searchForUser(String username) {
         if (logger.isDebugEnabled()) {
             logger.debug("Searching for user '" + username + "', with user search "
                 + this.toString());
         }
 
         LdapTemplate template = new LdapTemplate(initialDirContextFactory);
 
         template.setSearchControls(searchControls);
 
         try {
             LdapUserDetailsImpl.Essence user = (LdapUserDetailsImpl.Essence) template.searchForSingleEntry(searchBase,
                     searchFilter, new String[] {username}, userDetailsMapper);
             user.setUsername(username);
 
             return user.createUserDetails();
         } catch (IncorrectResultSizeDataAccessException notFound) {
             if (notFound.getActualSize() == 0) {
                 throw new UsernameNotFoundException("User " + username + " not found in directory.");
             }
             // Search should never return multiple results if properly configured, so just rethrow
             throw notFound;
         }
     }
 
     /**
      * Sets the corresponding property on the {@link SearchControls} instance used in the search.
      *
      * @param deref the derefLinkFlag value as defined in SearchControls..
      */
     public void setDerefLinkFlag(boolean deref) {
         searchControls.setDerefLinkFlag(deref);
     }
 
     /**
      * If true then searches the entire subtree as identified by context, if false (the default) then only
      * searches the level identified by the context.
      *
      * @param searchSubtree true the underlying search controls should be set to SearchControls.SUBTREE_SCOPE
      * rather than SearchControls.ONELEVEL_SCOPE.
      */
     public void setSearchSubtree(boolean searchSubtree) {
         searchControls.setSearchScope(searchSubtree ? SearchControls.SUBTREE_SCOPE : SearchControls.ONELEVEL_SCOPE);
     }
 
     /**
      * The time to wait before the search fails; the default is zero, meaning forever.
      *
      * @param searchTimeLimit the time limit for the search (in milliseconds).
      */
     public void setSearchTimeLimit(int searchTimeLimit) {
         searchControls.setTimeLimit(searchTimeLimit);
     }
 
     protected LdapUserDetailsMapper getUserDetailsMapper() {
         return userDetailsMapper;
     }
 
     public void setUserDetailsMapper(LdapUserDetailsMapper userDetailsMapper) {
         this.userDetailsMapper = userDetailsMapper;
     }
 
     public String toString() {
         StringBuffer sb = new StringBuffer();
 
         sb.append("[ searchFilter: '").append(searchFilter).append("', ");
         sb.append("searchBase: '").append(searchBase).append("'");
         sb.append(", scope: ")
           .append(searchControls.getSearchScope() == SearchControls.SUBTREE_SCOPE ? "subtree" : "single-level, ");
         sb.append("searchTimeLimit: ").append(searchControls.getTimeLimit());
         sb.append("derefLinkFlag: ").append(searchControls.getDerefLinkFlag()).append(" ]");
 
         return sb.toString();
     }
 }