/*
    *   Licensed to the Apache Software Foundation (ASF) under one
    *   or more contributor license agreements.  See the NOTICE file
    *   distributed with this work for additional information
    *   regarding copyright ownership.  The ASF licenses this file
    *   to you 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.apache.directory.server.core.api.schema.registries.synchronizers;
  
  
  import org.apache.directory.api.ldap.model.constants.MetaSchemaConstants;
  import org.apache.directory.api.ldap.model.constants.SchemaConstants;
  import org.apache.directory.api.ldap.model.entry.Entry;
  import org.apache.directory.api.ldap.model.exception.LdapException;
  import org.apache.directory.api.ldap.model.exception.LdapInvalidDnException;
  import org.apache.directory.api.ldap.model.exception.LdapSchemaViolationException;
  import org.apache.directory.api.ldap.model.exception.LdapUnwillingToPerformException;
  import org.apache.directory.api.ldap.model.message.ResultCodeEnum;
  import org.apache.directory.api.ldap.model.name.Dn;
  import org.apache.directory.api.ldap.model.name.Rdn;
  import org.apache.directory.api.ldap.model.schema.SchemaManager;
  import org.apache.directory.api.ldap.model.schema.SyntaxChecker;
  import org.apache.directory.api.ldap.model.schema.registries.Schema;
  import org.apache.directory.api.util.Strings;
  import org.apache.directory.server.core.api.interceptor.context.ModifyOperationContext;
  import org.apache.directory.server.i18n.I18n;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  
  /**
   * A synchronizer which detects changes to syntaxCheckers and updates the
   * {@link SchemaManager}.
   *
   * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
   */
  public class SyntaxCheckerSynchronizer extends AbstractRegistrySynchronizer
  {
      /** A logger for this class */
      private static final Logger LOG = LoggerFactory.getLogger( SyntaxCheckerSynchronizer.class );
  
  
      /**
       * Creates a new instance of SyntaxCheckerSynchronizer.
       *
       * @param schemaManager The global schemaManager
       * @throws Exception If the initialization failed
       */
      public SyntaxCheckerSynchronizer( SchemaManager schemaManager ) throws Exception
      {
          super( schemaManager );
      }
  
  
      /**
       * {@inheritDoc}
       */
      @Override
      public boolean modify( ModifyOperationContext modifyContext, Entry targetEntry, boolean cascade )
          throws LdapException
      {
          Dn name = modifyContext.getDn();
          Entry entry = modifyContext.getEntry();
          String schemaName = getSchemaName( name );
          String oid = getOid( entry );
          SyntaxChecker syntaxChecker = factory.getSyntaxChecker( schemaManager, targetEntry, schemaManager
              .getRegistries(), schemaName );
  
          if ( isSchemaEnabled( schemaName ) )
          {
              syntaxChecker.setSchemaName( schemaName );
  
              schemaManager.unregisterSyntaxChecker( oid );
              schemaManager.add( syntaxChecker );
  
              return SCHEMA_MODIFIED;
          }
  
          return SCHEMA_UNCHANGED;
      }
  
  
      /**
       * {@inheritDoc}
       */
      @Override
      public void add( Entry entry ) throws LdapException
     {
         Dn dn = entry.getDn();
         Dn parentDn = dn.getParent();
 
         // The parent Dn must be ou=syntaxcheckers,cn=<schemaName>,ou=schema
         checkParent( parentDn, schemaManager, SchemaConstants.SYNTAX_CHECKER );
 
         // The new schemaObject's OID must not already exist
         checkOidIsUniqueForSyntaxChecker( entry );
 
         // Build the new SyntaxChecker from the given entry
         String schemaName = getSchemaName( dn );
 
         SyntaxChecker syntaxChecker = factory.getSyntaxChecker( schemaManager, entry, schemaManager.getRegistries(),
             schemaName );
 
         // At this point, the constructed SyntaxChecker has not been checked against the
         // existing SchemaManager. It will be checked there, if the schema and the
         // SyntaxChecker are both enabled.
         Schema schema = schemaManager.getLoadedSchema( schemaName );
 
         if ( schema.isEnabled() && syntaxChecker.isEnabled() )
         {
             if ( schemaManager.add( syntaxChecker ) )
             {
                 LOG.debug( "Added {} into the enabled schema {}", dn.getName(), schemaName );
             }
             else
             {
                 String msg = I18n.err( I18n.ERR_386, entry.getDn().getName(),
                     Strings.listToString( schemaManager.getErrors() ) );
                 LOG.info( msg );
                 throw new LdapUnwillingToPerformException( ResultCodeEnum.UNWILLING_TO_PERFORM, msg );
             }
         }
         else
         {
             LOG.debug( "The SyntaxChecker {} cannot be added in the disabled schema {}", dn.getName(), schemaName );
         }
     }
 
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void delete( Entry entry, boolean cascade ) throws LdapException
     {
         Dn dn = entry.getDn();
         Dn parentDn = dn.getParent();
 
         // The parent Dn must be ou=syntaxcheckers,cn=<schemaName>,ou=schema
         checkParent( parentDn, schemaManager, SchemaConstants.SYNTAX_CHECKER );
 
         // Get the SyntaxChecker's instance
         String schemaName = getSchemaName( entry.getDn() );
 
         // Get the Schema
         Schema schema = schemaManager.getLoadedSchema( schemaName );
 
         if ( schema.isDisabled() )
         {
             // The schema is disabled, nothing to do.
             LOG.debug( "The SyntaxChecker {} cannot be deleted from the disabled schema {}", dn.getName(), schemaName );
 
             return;
         }
 
         // Test that the Oid exists
         SyntaxChecker syntaxChecker = null;
 
         try
         {
             syntaxChecker = checkSyntaxCheckerOidExists( entry );
         }
         catch ( LdapSchemaViolationException lsve )
         {
             // The syntaxChecker does not exist
             syntaxChecker = factory.getSyntaxChecker( schemaManager, entry, schemaManager.getRegistries(), schemaName );
 
             if ( schemaManager.getRegistries().contains( syntaxChecker ) )
             {
                 // Remove the syntaxChecker from the schema/SchemaObject Map
                 schemaManager.getRegistries().dissociateFromSchema( syntaxChecker );
 
                 // Ok, we can exit.
                 return;
             }
             else
             {
                 // Ok, definitively an error
                 String msg = I18n.err( I18n.ERR_387, entry.getDn().getName() );
                 LOG.info( msg );
                 throw new LdapSchemaViolationException( ResultCodeEnum.UNWILLING_TO_PERFORM, msg );
             }
         }
 
         if ( schema.isEnabled() && syntaxChecker.isEnabled() )
         {
             if ( schemaManager.delete( syntaxChecker ) )
             {
                 LOG.debug( "Deleted {} from the enabled schema {}", dn.getName(), schemaName );
             }
             else
             {
                 String msg = I18n.err( I18n.ERR_386, entry.getDn().getName(),
                     Strings.listToString( schemaManager.getErrors() ) );
                 LOG.info( msg );
                 throw new LdapUnwillingToPerformException( ResultCodeEnum.UNWILLING_TO_PERFORM, msg );
             }
         }
         else
         {
             LOG.debug( "The syntaxChecker {} cannot be deleted from the disabled schema {}", dn.getName(), schemaName );
         }
     }
 
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void rename( Entry entry, Rdn newRdn, boolean cascade ) throws LdapException
     {
         String oldOid = getOid( entry );
         String schemaName = getSchemaName( entry.getDn() );
 
         if ( schemaManager.getLdapSyntaxRegistry().contains( oldOid ) )
         {
             throw new LdapUnwillingToPerformException( ResultCodeEnum.UNWILLING_TO_PERFORM,
                 I18n.err( I18n.ERR_389, oldOid ) );
         }
 
         Entry targetEntry = entry.clone();
         String newOid = newRdn.getValue();
 
         if ( schemaManager.getSyntaxCheckerRegistry().contains( newOid ) )
         {
             throw new LdapSchemaViolationException( ResultCodeEnum.OTHER,
                 I18n.err( I18n.ERR_390, newOid ) );
         }
 
         targetEntry.put( MetaSchemaConstants.M_OID_AT, newOid );
 
         if ( isSchemaEnabled( schemaName ) )
         {
             SyntaxChecker syntaxChecker = factory.getSyntaxChecker( schemaManager, targetEntry, schemaManager
                 .getRegistries(), schemaName );
             schemaManager.unregisterSyntaxChecker( oldOid );
             schemaManager.add( syntaxChecker );
         }
     }
 
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void moveAndRename( Dn oriChildName, Dn newParentName, Rdn newRdn, boolean deleteOldRn,
         Entry entry, boolean cascade ) throws LdapException
     {
         checkNewParent( newParentName );
         String oldOid = getOid( entry );
         String oldSchemaName = getSchemaName( oriChildName );
         String newSchemaName = getSchemaName( newParentName );
 
         if ( schemaManager.getLdapSyntaxRegistry().contains( oldOid ) )
         {
             throw new LdapUnwillingToPerformException( ResultCodeEnum.UNWILLING_TO_PERFORM,
                 I18n.err( I18n.ERR_391, oldOid ) );
         }
 
         Entry targetEntry = entry.clone();
 
         String newOid = newRdn.getValue();
 
         if ( schemaManager.getSyntaxCheckerRegistry().contains( newOid ) )
         {
             throw new LdapSchemaViolationException( ResultCodeEnum.OTHER,
                 I18n.err( I18n.ERR_390, newOid ) );
         }
 
         targetEntry.put( MetaSchemaConstants.M_OID_AT, newOid );
         SyntaxChecker syntaxChecker = factory.getSyntaxChecker( schemaManager, targetEntry, schemaManager
             .getRegistries(), newSchemaName );
 
         if ( isSchemaEnabled( oldSchemaName ) )
         {
             schemaManager.unregisterSyntaxChecker( oldOid );
         }
 
         if ( isSchemaEnabled( newSchemaName ) )
         {
             schemaManager.add( syntaxChecker );
         }
     }
 
 
     /**
      * {@inheritDoc}
      */
     @Override
     public void move( Dn oriChildName, Dn newParentName, Entry entry, boolean cascade ) throws LdapException
     {
         checkNewParent( newParentName );
         String oid = getOid( entry );
         String oldSchemaName = getSchemaName( oriChildName );
         String newSchemaName = getSchemaName( newParentName );
 
         if ( schemaManager.getLdapSyntaxRegistry().contains( oid ) )
         {
             throw new LdapUnwillingToPerformException( ResultCodeEnum.UNWILLING_TO_PERFORM,
                 I18n.err( I18n.ERR_393, oid ) );
         }
 
         SyntaxChecker syntaxChecker = factory.getSyntaxChecker( schemaManager, entry, schemaManager.getRegistries(),
             newSchemaName );
 
         if ( isSchemaEnabled( oldSchemaName ) )
         {
             schemaManager.unregisterSyntaxChecker( oid );
         }
 
         if ( isSchemaEnabled( newSchemaName ) )
         {
             schemaManager.add( syntaxChecker );
         }
     }
 
 
     private void checkOidIsUniqueForSyntaxChecker( Entry entry ) throws LdapException
     {
         String oid = getOid( entry );
 
         if ( schemaManager.getNormalizerRegistry().contains( oid ) )
         {
             throw new LdapSchemaViolationException( ResultCodeEnum.OTHER,
                 I18n.err( I18n.ERR_390, oid ) );
         }
     }
 
 
     /**
      * Check that a SyntaxChecker exists in the SyntaxCheckerRegistry, and if so,
      * return it.
      * 
      * @param entry The entry to check
      * @return The found SyntaxChecker
      * @throws LdapException If the SyntaxChecker does not exist
      */
     protected SyntaxChecker checkSyntaxCheckerOidExists( Entry entry ) throws LdapException
     {
         String oid = getOid( entry );
 
         if ( schemaManager.getSyntaxCheckerRegistry().contains( oid ) )
         {
             return schemaManager.getSyntaxCheckerRegistry().get( oid );
         }
         else
         {
             throw new LdapSchemaViolationException( ResultCodeEnum.OTHER,
                 I18n.err( I18n.ERR_336, oid ) );
         }
     }
 
 
     private void checkNewParent( Dn newParent ) throws LdapException
     {
         if ( newParent.size() != 3 )
         {
             throw new LdapInvalidDnException( ResultCodeEnum.NAMING_VIOLATION,
                 I18n.err( I18n.ERR_396 ) );
         }
 
         Rdn rdn = newParent.getRdn();
         if ( !schemaManager.getAttributeTypeRegistry().getOidByName( rdn.getNormType() ).equals(
             SchemaConstants.OU_AT_OID ) )
         {
             throw new LdapInvalidDnException( ResultCodeEnum.NAMING_VIOLATION,
                 I18n.err( I18n.ERR_397 ) );
         }
 
         if ( !rdn.getValue().equalsIgnoreCase( SchemaConstants.SYNTAX_CHECKERS_AT ) )
         {
             throw new LdapInvalidDnException( ResultCodeEnum.NAMING_VIOLATION,
                 I18n.err( I18n.ERR_372 ) );
         }
     }
 }