/*
    * 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.portal.service.search;
  
  import fr.paris.lutece.portal.business.page.Page;
  import fr.paris.lutece.portal.business.page.PageHome;
  import fr.paris.lutece.portal.service.message.SiteMessageException;
  import fr.paris.lutece.portal.service.page.IPageService;
  import fr.paris.lutece.portal.service.spring.SpringContextService;
  import fr.paris.lutece.portal.service.util.AppException;
  import fr.paris.lutece.portal.service.util.AppPropertiesService;
  import fr.paris.lutece.util.url.UrlItem;
  
  import org.apache.commons.lang.StringUtils;
  
  import org.apache.lucene.document.DateTools;
  import org.apache.lucene.document.Document;
  import org.apache.lucene.document.Field;
  import org.apache.lucene.document.FieldType;
  import org.apache.lucene.document.StoredField;
  import org.apache.lucene.document.StringField;
  import org.apache.lucene.document.TextField;
  
  import org.apache.tika.exception.TikaException;
  import org.apache.tika.metadata.Metadata;
  import org.apache.tika.parser.ParseContext;
  import org.apache.tika.parser.html.HtmlParser;
  import org.apache.tika.sax.BodyContentHandler;
  
  import org.xml.sax.ContentHandler;
  import org.xml.sax.SAXException;
  
  import java.io.ByteArrayInputStream;
  import java.io.IOException;
  
  import java.util.ArrayList;
  import java.util.List;
  
  
  /**
   * Indexer service for pages
   */
  public class PageIndexer implements SearchIndexer
  {
      public static final String INDEX_TYPE_PAGE = "Page";
      public static final String INDEXER_NAME = "PageIndexer";
      protected static final String PROPERTY_PAGE_BASE_URL = "search.pageIndexer.baseUrl";
      protected static final String PROPERTY_SEARCH_PAGE_URL = "search.pageSearch.baseUrl";
      protected static final String PROPERTY_INDEXER_ENABLE = "search.pageIndexer.enable";
      protected static final String PARAMETER_PAGE_ID = "page_id";
      protected static IPageService _pageService = (IPageService) SpringContextService.getBean( "pageService" );
      private static final String INDEXER_DESCRIPTION = "Indexer service for pages";
      private static final String INDEXER_VERSION = "1.0.0";
  
      /**
       * {@inheritDoc}
       */
      @Override
      public void indexDocuments(  ) throws IOException, InterruptedException, SiteMessageException
      {
          String strPageBaseUrl = AppPropertiesService.getProperty( PROPERTY_PAGE_BASE_URL );
          List<Page> listPages = PageHome.getAllPages(  );
  
          for ( Page page : listPages )
          {
              UrlItem url = new UrlItem( strPageBaseUrl );
              url.addParameter( PARAMETER_PAGE_ID, page.getId(  ) );
  
             Document doc = null;
 
             try
             {
                 doc = getDocument( page, url.getUrl(  ) );
             }
             catch ( Exception e )
             {
                 String strMessage = "Page ID : " + page.getId(  );
                 IndexationService.error( this, e, strMessage );
             }
 
             if ( doc != null )
             {
                 IndexationService.write( doc );
             }
         }
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public List<Document> getDocuments( String nIdDocument )
         throws IOException, InterruptedException, SiteMessageException
     {
         ArrayList<Document> listDocuments = new ArrayList<Document>(  );
         String strPageBaseUrl = AppPropertiesService.getProperty( PROPERTY_PAGE_BASE_URL );
 
         Page page = PageHome.getPage( Integer.parseInt( nIdDocument ) );
 
         if ( ( page != null ) && ( page.getId(  ) != 0 ) )
         {
             UrlItem url = new UrlItem( strPageBaseUrl );
             url.addParameter( PARAMETER_PAGE_ID, page.getId(  ) );
 
             Document doc = getDocument( page, url.getUrl(  ) );
             listDocuments.add( doc );
         }
 
         return listDocuments;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public String getName(  )
     {
         return INDEXER_NAME;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public String getVersion(  )
     {
         return INDEXER_VERSION;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public String getDescription(  )
     {
         return INDEXER_DESCRIPTION;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public boolean isEnable(  )
     {
         String strEnable = AppPropertiesService.getProperty( PROPERTY_INDEXER_ENABLE, Boolean.TRUE.toString(  ) );
 
         return ( strEnable.equalsIgnoreCase( Boolean.TRUE.toString(  ) ) );
     }
 
     /**
      * Builds a document which will be used by Lucene during the indexing of the
      * pages of the site with the following
      * fields : summary, uid, url, contents, title and description.
      * @return the built Document
      * @param strUrl The base URL for documents
      * @param page the page to index
      * @throws IOException The IO Exception
      * @throws InterruptedException The InterruptedException
      * @throws SiteMessageException occurs when a site message need to be
      *             displayed
      */
     protected Document getDocument( Page page, String strUrl )
         throws IOException, InterruptedException, SiteMessageException
     {
         FieldType ft = new FieldType( StringField.TYPE_STORED );
         ft.setOmitNorms( false );
 
         FieldType ftNotStored = new FieldType( StringField.TYPE_NOT_STORED );
         ftNotStored.setOmitNorms( false );
         ftNotStored.setTokenized( false );
 
         // make a new, empty document
         Document doc = new Document(  );
 
         // Add the url as a field named "url".  Use an UnIndexed field, so
         // that the url is just stored with the document, but is not searchable.
         doc.add( new Field( SearchItem.FIELD_URL, strUrl, ft ) );
 
         // Add the last modified date of the file a field named "modified".
         // Use a field that is indexed (i.e. searchable), but don't tokenize
         // the field into words.
         String strDate = DateTools.dateToString( page.getDateUpdate(  ), DateTools.Resolution.DAY );
         doc.add( new Field( SearchItem.FIELD_DATE, strDate, ft ) );
 
         // Add the uid as a field, so that index can be incrementally maintained.
         // This field is not stored with document, it is indexed, but it is not
         // tokenized prior to indexing.
         String strIdPage = String.valueOf( page.getId(  ) );
         doc.add( new Field( SearchItem.FIELD_UID, strIdPage, ftNotStored ) );
 
         String strPageContent = _pageService.getPageContent( page.getId(  ), 0, null );
         ContentHandler handler = new BodyContentHandler(  );
         Metadata metadata = new Metadata(  );
 
         try
         {
             new HtmlParser(  ).parse( new ByteArrayInputStream( strPageContent.getBytes(  ) ), handler, metadata,
                 new ParseContext(  ) );
         }
         catch ( SAXException e )
         {
             throw new AppException( "Error during page parsing." );
         }
         catch ( TikaException e )
         {
             throw new AppException( "Error during page parsing." );
         }
 
         //the content of the article is recovered in the parser because this one
         //had replaced the encoded caracters (as &eacute;) by the corresponding special caracter (as ?)
         StringBuilder sb = new StringBuilder( handler.toString(  ) );
 
         // Add the tag-stripped contents as a Reader-valued Text field so it will
         // get tokenized and indexed.
         StringBuilder sbFieldContent = new StringBuilder(  );
         StringBuilder sbFieldMetadata = new StringBuilder(  );
         sbFieldContent.append( page.getName(  ) ).append( " " ).append( sb.toString(  ) );
 
         // Add the metadata description of the page if it exists
         if ( page.getDescription(  ) != null )
         {
             sbFieldContent.append( " " ).append( page.getDescription(  ) );
         }
 
         // Add the metadata keywords of the page if it exists
         String strMetaKeywords = page.getMetaKeywords(  );
 
         if ( StringUtils.isNotBlank( strMetaKeywords ) )
         {
             sbFieldContent.append( " " ).append( strMetaKeywords );
             sbFieldMetadata.append( strMetaKeywords );
         }
 
         doc.add( new Field( SearchItem.FIELD_CONTENTS, sbFieldContent.toString(  ), TextField.TYPE_NOT_STORED ) );
 
         if ( StringUtils.isNotBlank( page.getMetaDescription(  ) ) )
         {
             if ( sbFieldMetadata.length(  ) > 0 )
             {
                 sbFieldMetadata.append( " " );
             }
 
             sbFieldMetadata.append( page.getMetaDescription(  ) );
         }
 
         if ( sbFieldMetadata.length(  ) > 0 )
         {
             doc.add( new StringField( SearchItem.FIELD_METADATA, sbFieldMetadata.toString(  ), Field.Store.NO ) );
         }
 
         // Add the title as a separate Text field, so that it can be searched
         // separately.
         doc.add( new Field( SearchItem.FIELD_TITLE, page.getName(  ), ft ) );
 
         if ( StringUtils.isNotBlank( page.getDescription(  ) ) )
         {
             // Add the summary as an UnIndexed field, so that it is stored and returned
             // with hit documents for display.
             doc.add( new StoredField( SearchItem.FIELD_SUMMARY, page.getDescription(  ) ) );
         }
 
         doc.add( new Field( SearchItem.FIELD_TYPE, INDEX_TYPE_PAGE, ft ) );
         doc.add( new Field( SearchItem.FIELD_ROLE, page.getRole(  ), ft ) );
 
         // return the document
         return doc;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public List<String> getListType(  )
     {
         List<String> listType = new ArrayList<String>(  );
         listType.add( INDEX_TYPE_PAGE );
 
         return listType;
     }
 
     /**
      * {@inheritDoc}
      */
     @Override
     public String getSpecificSearchAppUrl(  )
     {
         return AppPropertiesService.getProperty( PROPERTY_SEARCH_PAGE_URL );
     }
 }