/*
    *  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.api.ldap.schema.loader;
  
  
  import java.io.File;
  import java.io.IOException;
  import java.io.InputStream;
  import java.net.URL;
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Map;
  import java.util.regex.Pattern;
  
  import org.apache.directory.api.i18n.I18n;
  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.ldif.LdifEntry;
  import org.apache.directory.api.ldap.model.ldif.LdifReader;
  import org.apache.directory.api.ldap.model.schema.registries.AbstractSchemaLoader;
  import org.apache.directory.api.ldap.model.schema.registries.Schema;
  import org.apache.directory.api.ldap.schema.extractor.impl.DefaultSchemaLdifExtractor;
  import org.apache.directory.api.ldap.schema.extractor.impl.ResourceMap;
  import org.apache.directory.api.util.Strings;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  
  /**
   * Loads schema data from LDIF files containing entries representing schema
   * objects, using the meta schema format.
   * 
   * This class is used only for tests.
   *
   * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
   */
  public class JarLdifSchemaLoader extends AbstractSchemaLoader
  {
      /**
       * Filesystem path separator pattern, either forward slash or backslash.
       * java.util.regex.Pattern is immutable so only one instance is needed for all uses.
       */
      private static final String SEPARATOR_PATTERN = "[/\\Q\\\\E]";
  
      /** ldif file extension used */
      private static final String LDIF_EXT = "ldif";
  
      /** static class logger */
      private static final Logger LOG = LoggerFactory.getLogger( JarLdifSchemaLoader.class );
  
      /** Speedup for DEBUG mode */
      private static final boolean IS_DEBUG = LOG.isDebugEnabled();
  
      /** a map of all the resources in this jar */
      private static final Map<String, Boolean> RESOURCE_MAP = ResourceMap.getResources( Pattern
          .compile( "schema" + SEPARATOR_PATTERN + "ou=schema.*" ) );
  
  
      /**
       * Creates a new LDIF based SchemaLoader. The constructor checks to make
       * sure the supplied base directory exists and contains a schema.ldif file
       * and if not complains about it.
       *
       * @throws LdapException if the base directory does not exist or does not
       * a valid schema.ldif file
       * @throws IOException If we can't load the schema
       */
      public JarLdifSchemaLoader() throws IOException, LdapException
      {
          initializeSchemas();
      }
  
  
      private URL getResource( String resource, String msg ) throws IOException
      {
          if ( RESOURCE_MAP.get( resource ) )
          {
              return DefaultSchemaLdifExtractor.getUniqueResource( resource, msg );
          }
          else
          {
             return new File( resource ).toURI().toURL();
         }
     }
 
 
     /**
      * Scans for LDIF files just describing the various schema contained in
      * the schema repository.
      *
      * @throws LdapException
      */
     private void initializeSchemas() throws IOException, LdapException
     {
         if ( IS_DEBUG )
         {
             LOG.debug( "Initializing schema" );
         }
 
         Pattern pat = Pattern.compile( "schema" + SEPARATOR_PATTERN + "ou=schema"
             + SEPARATOR_PATTERN + "cn=[a-z0-9-_]*\\." + LDIF_EXT );
 
         for ( String file : RESOURCE_MAP.keySet() )
         {
             if ( pat.matcher( file ).matches() )
             {
                 URL resource = getResource( file, "schema LDIF file" );
                 InputStream in = resource.openStream();
 
                 try
                 {
                     LdifReader reader = new LdifReader( in );
                     LdifEntry entry = reader.next();
                     reader.close();
                     Schema schema = getSchema( entry.getEntry() );
                     schemaMap.put( schema.getSchemaName(), schema );
 
                     if ( IS_DEBUG )
                     {
                         LOG.debug( "Schema Initialized ... \n{}", schema );
                     }
                 }
                 catch ( LdapException le )
                 {
                     LOG.error( I18n.err( I18n.ERR_10003, file ), le );
                     throw le;
                 }
                 finally
                 {
                     in.close();
                 }
             }
         }
     }
 
 
     /**
      * Utility method to get a regex.Pattern fragment for the path for a schema directory.
      *
      * @param schema the schema to get the path for
      * @return the regex.Pattern fragment for the path for the specified schema directory
      */
     private String getSchemaDirectoryString( Schema schema )
     {
         return "schema" + "/" + "ou=schema" + "/"
             + "cn=" + Strings.lowerCase( schema.getSchemaName() ) + "/";
     }
 
 
     /**
      * {@inheritDoc}
      */
     @Override
     public List<Entry> loadComparators( Schema... schemas ) throws LdapException, IOException
     {
         List<Entry> comparatorList = new ArrayList<>();
 
         if ( schemas == null )
         {
             return comparatorList;
         }
 
         for ( Schema schema : schemas )
         {
             String start = getSchemaDirectoryString( schema )
                 + SchemaConstants.COMPARATORS_PATH + "/" + "m-oid=";
             String end = "." + LDIF_EXT;
 
             for ( String resourcePath : RESOURCE_MAP.keySet() )
             {
                 if ( resourcePath.startsWith( start ) && resourcePath.endsWith( end ) )
                 {
                     URL resource = getResource( resourcePath, "comparator LDIF file" );
                     LdifReader reader = new LdifReader( resource.openStream() );
                     LdifEntry entry = reader.next();
                     reader.close();
 
                     comparatorList.add( entry.getEntry() );
                 }
             }
         }
 
         return comparatorList;
     }
 
 
     /**
      * {@inheritDoc}
      */
     @Override
     public List<Entry> loadSyntaxCheckers( Schema... schemas ) throws LdapException, IOException
     {
         List<Entry> syntaxCheckerList = new ArrayList<>();
 
         if ( schemas == null )
         {
             return syntaxCheckerList;
         }
 
         for ( Schema schema : schemas )
         {
             String start = getSchemaDirectoryString( schema )
                 + SchemaConstants.SYNTAX_CHECKERS_PATH + "/" + "m-oid=";
             String end = "." + LDIF_EXT;
 
             for ( String resourcePath : RESOURCE_MAP.keySet() )
             {
                 if ( resourcePath.startsWith( start ) && resourcePath.endsWith( end ) )
                 {
                     URL resource = getResource( resourcePath, "syntaxChecker LDIF file" );
                     LdifReader reader = new LdifReader( resource.openStream() );
                     LdifEntry entry = reader.next();
                     reader.close();
 
                     syntaxCheckerList.add( entry.getEntry() );
                 }
             }
         }
 
         return syntaxCheckerList;
     }
 
 
     /**
      * {@inheritDoc}
      */
     @Override
     public List<Entry> loadNormalizers( Schema... schemas ) throws LdapException, IOException
     {
         List<Entry> normalizerList = new ArrayList<>();
 
         if ( schemas == null )
         {
             return normalizerList;
         }
 
         for ( Schema schema : schemas )
         {
             String start = getSchemaDirectoryString( schema )
                 + SchemaConstants.NORMALIZERS_PATH + "/" + "m-oid=";
             String end = "." + LDIF_EXT;
 
             for ( String resourcePath : RESOURCE_MAP.keySet() )
             {
                 if ( resourcePath.startsWith( start ) && resourcePath.endsWith( end ) )
                 {
                     URL resource = getResource( resourcePath, "normalizer LDIF file" );
                     LdifReader reader = new LdifReader( resource.openStream() );
                     LdifEntry entry = reader.next();
                     reader.close();
 
                     normalizerList.add( entry.getEntry() );
                 }
             }
         }
 
         return normalizerList;
     }
 
 
     /**
      * {@inheritDoc}
      */
     @Override
     public List<Entry> loadMatchingRules( Schema... schemas ) throws LdapException, IOException
     {
         List<Entry> matchingRuleList = new ArrayList<>();
 
         if ( schemas == null )
         {
             return matchingRuleList;
         }
 
         for ( Schema schema : schemas )
         {
             String start = getSchemaDirectoryString( schema )
                 + SchemaConstants.MATCHING_RULES_PATH + "/" + "m-oid=";
             String end = "." + LDIF_EXT;
 
             for ( String resourcePath : RESOURCE_MAP.keySet() )
             {
                 if ( resourcePath.startsWith( start ) && resourcePath.endsWith( end ) )
                 {
                     URL resource = getResource( resourcePath, "matchingRules LDIF file" );
                     LdifReader reader = new LdifReader( resource.openStream() );
                     LdifEntry entry = reader.next();
                     reader.close();
 
                     matchingRuleList.add( entry.getEntry() );
                 }
             }
         }
 
         return matchingRuleList;
     }
 
 
     /**
      * {@inheritDoc}
      */
     @Override
     public List<Entry> loadSyntaxes( Schema... schemas ) throws LdapException, IOException
     {
         List<Entry> syntaxList = new ArrayList<>();
 
         if ( schemas == null )
         {
             return syntaxList;
         }
 
         for ( Schema schema : schemas )
         {
             String start = getSchemaDirectoryString( schema )
                 + SchemaConstants.SYNTAXES_PATH + "/" + "m-oid=";
             String end = "." + LDIF_EXT;
 
             for ( String resourcePath : RESOURCE_MAP.keySet() )
             {
                 if ( resourcePath.startsWith( start ) && resourcePath.endsWith( end ) )
                 {
                     URL resource = getResource( resourcePath, "syntax LDIF file" );
                     LdifReader reader = new LdifReader( resource.openStream() );
                     LdifEntry entry = reader.next();
                     reader.close();
 
                     syntaxList.add( entry.getEntry() );
                 }
             }
         }
 
         return syntaxList;
     }
 
 
     /**
      * {@inheritDoc}
      */
     @Override
     public List<Entry> loadAttributeTypes( Schema... schemas ) throws LdapException, IOException
     {
         List<Entry> attributeTypeList = new ArrayList<>();
 
         if ( schemas == null )
         {
             return attributeTypeList;
         }
 
         for ( Schema schema : schemas )
         {
             // check that the attributeTypes directory exists for the schema
             String start = getSchemaDirectoryString( schema )
                 + SchemaConstants.ATTRIBUTE_TYPES_PATH + "/" + "m-oid=";
             String end = "." + LDIF_EXT;
 
             // get list of attributeType LDIF schema files in attributeTypes
             for ( String resourcePath : RESOURCE_MAP.keySet() )
             {
                 if ( resourcePath.startsWith( start ) && resourcePath.endsWith( end ) )
                 {
                     URL resource = getResource( resourcePath, "attributeType LDIF file" );
                     LdifReader reader = new LdifReader( resource.openStream() );
                     LdifEntry entry = reader.next();
                     reader.close();
 
                     attributeTypeList.add( entry.getEntry() );
                 }
             }
         }
 
         return attributeTypeList;
     }
 
 
     /**
      * {@inheritDoc}
      */
     @Override
     public List<Entry> loadMatchingRuleUses( Schema... schemas ) throws LdapException, IOException
     {
         List<Entry> matchingRuleUseList = new ArrayList<>();
 
         if ( schemas == null )
         {
             return matchingRuleUseList;
         }
 
         for ( Schema schema : schemas )
         {
             String start = getSchemaDirectoryString( schema )
                 + SchemaConstants.MATCHING_RULE_USE_PATH + "/" + "m-oid=";
             String end = "." + LDIF_EXT;
 
             for ( String resourcePath : RESOURCE_MAP.keySet() )
             {
                 if ( resourcePath.startsWith( start ) && resourcePath.endsWith( end ) )
                 {
                     URL resource = getResource( resourcePath, "matchingRuleUse LDIF file" );
                     LdifReader reader = new LdifReader( resource.openStream() );
                     LdifEntry entry = reader.next();
                     reader.close();
 
                     matchingRuleUseList.add( entry.getEntry() );
                 }
             }
         }
 
         return matchingRuleUseList;
     }
 
 
     /**
      * {@inheritDoc}
      */
     @Override
     public List<Entry> loadNameForms( Schema... schemas ) throws LdapException, IOException
     {
         List<Entry> nameFormList = new ArrayList<>();
 
         if ( schemas == null )
         {
             return nameFormList;
         }
 
         for ( Schema schema : schemas )
         {
             String start = getSchemaDirectoryString( schema )
                 + SchemaConstants.NAME_FORMS_PATH + "/" + "m-oid=";
             String end = "." + LDIF_EXT;
 
             for ( String resourcePath : RESOURCE_MAP.keySet() )
             {
                 if ( resourcePath.startsWith( start ) && resourcePath.endsWith( end ) )
                 {
                     URL resource = getResource( resourcePath, "nameForm LDIF file" );
                     LdifReader reader = new LdifReader( resource.openStream() );
                     LdifEntry entry = reader.next();
                     reader.close();
 
                     nameFormList.add( entry.getEntry() );
                 }
             }
         }
 
         return nameFormList;
     }
 
 
     /**
      * {@inheritDoc}
      */
     @Override
     public List<Entry> loadDitContentRules( Schema... schemas ) throws LdapException, IOException
     {
         List<Entry> ditContentRulesList = new ArrayList<>();
 
         if ( schemas == null )
         {
             return ditContentRulesList;
         }
 
         for ( Schema schema : schemas )
         {
             String start = getSchemaDirectoryString( schema )
                 + SchemaConstants.DIT_CONTENT_RULES_PATH + "/" + "m-oid=";
             String end = "." + LDIF_EXT;
 
             for ( String resourcePath : RESOURCE_MAP.keySet() )
             {
                 if ( resourcePath.startsWith( start ) && resourcePath.endsWith( end ) )
                 {
                     URL resource = getResource( resourcePath, "ditContentRule LDIF file" );
                     LdifReader reader = new LdifReader( resource.openStream() );
                     LdifEntry entry = reader.next();
                     reader.close();
 
                     ditContentRulesList.add( entry.getEntry() );
                 }
             }
         }
 
         return ditContentRulesList;
     }
 
 
     /**
      * {@inheritDoc}
      */
     @Override
     public List<Entry> loadDitStructureRules( Schema... schemas ) throws LdapException, IOException
     {
         List<Entry> ditStructureRuleList = new ArrayList<>();
 
         if ( schemas == null )
         {
             return ditStructureRuleList;
         }
 
         for ( Schema schema : schemas )
         {
             String start = getSchemaDirectoryString( schema )
                 + SchemaConstants.DIT_STRUCTURE_RULES_PATH + "/" + "m-oid=";
             String end = "." + LDIF_EXT;
 
             for ( String resourcePath : RESOURCE_MAP.keySet() )
             {
                 if ( resourcePath.startsWith( start ) && resourcePath.endsWith( end ) )
                 {
                     URL resource = getResource( resourcePath, "ditStructureRule LDIF file" );
                     LdifReader reader = new LdifReader( resource.openStream() );
                     LdifEntry entry = reader.next();
                     reader.close();
 
                     ditStructureRuleList.add( entry.getEntry() );
                 }
             }
         }
 
         return ditStructureRuleList;
     }
 
 
     /**
      * {@inheritDoc}
      */
     @Override
     public List<Entry> loadObjectClasses( Schema... schemas ) throws LdapException, IOException
     {
         List<Entry> objectClassList = new ArrayList<>();
 
         if ( schemas == null )
         {
             return objectClassList;
         }
 
         for ( Schema schema : schemas )
         {
             // get objectClasses directory, check if exists, return if not
             String start = getSchemaDirectoryString( schema )
                 + SchemaConstants.OBJECT_CLASSES_PATH + "/" + "m-oid=";
             String end = "." + LDIF_EXT;
 
             for ( String resourcePath : RESOURCE_MAP.keySet() )
             {
                 if ( resourcePath.startsWith( start ) && resourcePath.endsWith( end ) )
                 {
                     URL resource = getResource( resourcePath, "objectClass LDIF file" );
                     LdifReader reader = new LdifReader( resource.openStream() );
                     LdifEntry entry = reader.next();
                     reader.close();
 
                     objectClassList.add( entry.getEntry() );
                 }
             }
         }
 
         return objectClassList;
     }
 }