/*
    * 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.plugins.directory.service.directorysearch;
  
  import java.io.IOException;
  import java.nio.file.Paths;
  
  import org.apache.commons.lang3.mutable.MutableBoolean;
  import org.apache.lucene.analysis.Analyzer;
  import org.apache.lucene.index.DirectoryReader;
  import org.apache.lucene.index.IndexWriter;
  import org.apache.lucene.index.IndexWriterConfig;
  import org.apache.lucene.index.IndexWriterConfig.OpenMode;
  import org.apache.lucene.search.IndexSearcher;
  import org.apache.lucene.store.Directory;
  import org.apache.lucene.store.NIOFSDirectory;
  
  import fr.paris.lutece.plugins.lucene.service.analyzer.LuteceFrenchAnalyzer;
  import fr.paris.lutece.portal.service.util.AppLogService;
  import fr.paris.lutece.portal.service.util.AppPathService;
  import fr.paris.lutece.portal.service.util.AppPropertiesService;
  
  /**
   * Factory for the search on Directory
   */
  public class DirectorySearchFactory
  {
      // Constants
      private static final String PATH_INDEX = "directory.internalIndexer.lucene.indexPath";
      private static final String PROPERTY_ANALYSER_CLASS_NAME = "directory.internalIndexer.lucene.analyser.className";
  
      // Variables
      private Analyzer _analyzer;
  
      /**
       * Constructor
       */
      private DirectorySearchFactory( )
      {
          try
          {
              String strAnalyserClassName = AppPropertiesService.getProperty( PROPERTY_ANALYSER_CLASS_NAME );
              _analyzer = (Analyzer) Class.forName( strAnalyserClassName ).newInstance( );
          }
          catch( InstantiationException | IllegalAccessException | ClassNotFoundException exception )
          {
              AppLogService.error( "Failed to instanciate the analyzer of the type: " + PROPERTY_ANALYSER_CLASS_NAME );
  
              _analyzer = new LuteceFrenchAnalyzer( );
          }
      }
  
      /**
       * Return the instance of the DirectorySearchFactory
       * 
       * @return the instance of the DirectorySearchFactory
       */
      public static DirectorySearchFactory getInstance( )
      {
          return DirectorySearchFactoryHolder._instance;
      }
  
      /**
       * Return the Analyzer to use for the search
       * 
       * @return the Analyzer to use for the search
       */
      public Analyzer getAnalyzer( )
     {
         return _analyzer;
     }
 
     /**
      * Return the IndexSearcher to use for the search
      * 
      * @return the index searcher to use for the search
      * @throws IOException
      *             - if there is a low-level IO error
      */
     public IndexSearcher getIndexSearcher( ) throws IOException
     {
         Directory luceneDirectory = getDirectory( );
 
         return new IndexSearcher( DirectoryReader.open( luceneDirectory ) );
     }
 
     /**
      * Create the IndexWriter with its configuration
      * 
      * @param bCreateIndex
      *            The boolean which tell if the index must be created
      * @return the created IndexWriter
      * @throws IOException
      *             - if there is a low level IO error
      */
     public IndexWriter getIndexWriter( MutableBoolean bCreateIndex ) throws IOException
     {
         Directory luceneDirectory = getDirectory( );
 
         if ( !DirectoryReader.indexExists( luceneDirectory ) )
         {
             bCreateIndex.setValue( Boolean.TRUE );
         }
 
         IndexWriterConfig conf = new IndexWriterConfig( getAnalyzer( ) );
 
         if ( bCreateIndex.isTrue( ) )
         {
             conf.setOpenMode( OpenMode.CREATE );
         }
         else
         {
             conf.setOpenMode( OpenMode.APPEND );
         }
 
         return new IndexWriter( luceneDirectory, conf );
     }
 
     /**
      * Return the Directory to use for the search
      * 
      * @return the Directory to use for the search
      * @throws IOException
      *             - if the path string cannot be converted to a Path
      */
     private Directory getDirectory( ) throws IOException
     {
         String strIndex = AppPathService.getPath( PATH_INDEX );
 
         return NIOFSDirectory.open( Paths.get( strIndex ) );
     }
 
     /**
      * Holder to manage the DirectorySearchFactory singleton
      */
     private static class DirectorySearchFactoryHolder
     {
         public static final DirectorySearchFactory _instance = new DirectorySearchFactory( );
     }
 }