/* 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.providers.ldap.authenticator;
  
  import org.acegisecurity.AcegiMessageSource;
  
  import org.acegisecurity.ldap.InitialDirContextFactory;
  import org.acegisecurity.ldap.LdapEntryMapper;
  import org.acegisecurity.ldap.LdapUserSearch;
  
  import org.acegisecurity.providers.ldap.LdapAuthenticator;
  
  import org.acegisecurity.userdetails.ldap.LdapUserDetailsMapper;
  
  import org.springframework.beans.factory.InitializingBean;
  
  import org.springframework.context.MessageSource;
  import org.springframework.context.MessageSourceAware;
  import org.springframework.context.support.MessageSourceAccessor;
  
  import org.springframework.util.Assert;
  
  import java.text.MessageFormat;
  
  import java.util.ArrayList;
  import java.util.List;
  
  
  /**
   * Base class for the authenticator implementations.
   *
   * @author Luke Taylor
   * @version $Id: AbstractLdapAuthenticator.java 1585 2006-07-20 13:15:55Z carlossg $
   */
  public abstract class AbstractLdapAuthenticator implements LdapAuthenticator, InitializingBean, MessageSourceAware {
      //~ Instance fields ================================================================================================
  
      private InitialDirContextFactory initialDirContextFactory;
      private LdapUserDetailsMapper userDetailsMapper = new LdapUserDetailsMapper();
  
      /** Optional search object which can be used to locate a user when a simple DN match isn't sufficient */
      private LdapUserSearch userSearch;
      protected MessageSourceAccessor messages = AcegiMessageSource.getAccessor();
  
      /**
       * The suffix to be added to the DN patterns, worked out internally from the root DN of the configured
       * InitialDirContextFactory.
       */
      private String dnSuffix = "";
  
      /** The attributes which will be retrieved from the directory. Null means all attributes */
      private String[] userAttributes = null;
  
      //private String[] userDnPattern = null;
      /** Stores the patterns which are used as potential DN matches */
      private MessageFormat[] userDnFormat = null;
  
      //~ Constructors ===================================================================================================
  
      /**
       * Create an initialized instance to the {@link InitialDirContextFactory} provided.
       * 
       * @param initialDirContextFactory
       */
      public AbstractLdapAuthenticator(InitialDirContextFactory initialDirContextFactory) {
          this.setInitialDirContextFactory(initialDirContextFactory);
      }
  
      // ~ Methods
      // ========================================================================================================
  
      public void afterPropertiesSet() throws Exception {
          Assert.isTrue((userDnFormat != null) || (userSearch != null),
                  "Either an LdapUserSearch or DN pattern (or both) must be supplied.");
      }
  
      /**
       * Set the {@link InitialDirContextFactory} and initialize this instance from its data.
       * 
       * @param initialDirContextFactory
       */
      private void setInitialDirContextFactory(InitialDirContextFactory initialDirContextFactory) {
          Assert.notNull(initialDirContextFactory, "initialDirContextFactory must not be null.");
          this.initialDirContextFactory = initialDirContextFactory;
  
          String rootDn = initialDirContextFactory.getRootDn();
 
         if (rootDn.length() > 0) {
             dnSuffix = "," + rootDn;
         }
     }
 
     protected InitialDirContextFactory getInitialDirContextFactory() {
         return initialDirContextFactory;
     }
 
     public String[] getUserAttributes() {
         return userAttributes;
     }
 
     protected LdapEntryMapper getUserDetailsMapper() {
         return userDetailsMapper;
     }
 
     /**
      * Builds list of possible DNs for the user, worked out from the <tt>userDnPatterns</tt> property. The
      * returned value includes the root DN of the provider URL used to configure the
      * <tt>InitialDirContextfactory</tt>.
      *
      * @param username the user's login name
      *
      * @return the list of possible DN matches, empty if <tt>userDnPatterns</tt> wasn't set.
      */
     protected List getUserDns(String username) {
         if (userDnFormat == null) {
             return new ArrayList(0);
         }
 
         List userDns = new ArrayList(userDnFormat.length);
         String[] args = new String[] {username};
 
         synchronized (userDnFormat) {
             for (int i = 0; i < userDnFormat.length; i++) {
                 userDns.add(userDnFormat[i].format(args) + dnSuffix);
             }
         }
 
         return userDns;
     }
 
     protected LdapUserSearch getUserSearch() {
         return userSearch;
     }
 
     public void setMessageSource(MessageSource messageSource) {
         Assert.notNull("Message source must not be null");
         this.messages = new MessageSourceAccessor(messageSource);
     }
 
     /**
      * Sets the user attributes which will be retrieved from the directory.
      *
      * @param userAttributes
      */
     public void setUserAttributes(String[] userAttributes) {
         Assert.notNull(userAttributes, "The userAttributes property cannot be set to null");
         this.userAttributes = userAttributes;
     }
 
     public void setUserDetailsMapper(LdapUserDetailsMapper userDetailsMapper) {
         Assert.notNull("userDetailsMapper must not be null");
         this.userDetailsMapper = userDetailsMapper;
     }
 
     /**
      * Sets the pattern which will be used to supply a DN for the user. The pattern should be the name relative
      * to the root DN. The pattern argument {0} will contain the username. An example would be "cn={0},ou=people".
      *
      * @param dnPattern the array of patterns which will be tried when obtaining a username
      * to a DN.
      */
     public void setUserDnPatterns(String[] dnPattern) {
         Assert.notNull(dnPattern, "The array of DN patterns cannot be set to null");
 //        this.userDnPattern = dnPattern;
         userDnFormat = new MessageFormat[dnPattern.length];
 
         for (int i = 0; i < dnPattern.length; i++) {
             userDnFormat[i] = new MessageFormat(dnPattern[i]);
         }
     }
 
     public void setUserSearch(LdapUserSearch userSearch) {
         Assert.notNull(userSearch, "The userSearch cannot be set to null");
         this.userSearch = userSearch;
     }
 }