/**

  * Distribution License:

  * JSword is free software; you can redistribute it and/or modify it under

  * the terms of the GNU Lesser General Public License, version 2.1 or later

  * as published by the Free Software Foundation. This program is distributed

  * in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even

  * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

  * See the GNU Lesser General Public License for more details.

  *

  * The License is available on the internet at:

  *      http://www.gnu.org/copyleft/lgpl.html

  * or by writing to:

  *      Free Software Foundation, Inc.

  *      59 Temple Place - Suite 330

  *      Boston, MA 02111-1307, USA

  *

  * © CrossWire Bible Society, 2007 - 2016

  *

  */

 package org.crosswire.jsword.index.lucene.analysis;

 import java.io.IOException;

 import org.apache.lucene.analysis.TokenStream;

 import org.apache.lucene.analysis.tokenattributes.TermAttribute;

 import org.crosswire.jsword.JSMsg;

 import org.crosswire.jsword.book.Book;

 import org.crosswire.jsword.book.study.StrongsNumber;

 import org.slf4j.Logger;

 import org.slf4j.LoggerFactory;

 /**

  * A StrongsNumberFilter normalizes Strong's Numbers.

  * 

  * @see gnu.lgpl.License The GNU Lesser General Public License for details.

  * @author DM Smith

  */

 public class StrongsNumberFilter extends AbstractBookTokenFilter {

     /**

      * Construct filtering <i>in</i>.

      * 

      * @param in 

      */

     public StrongsNumberFilter(TokenStream in) {

         this(null, in);

     }

     /**

      * Construct filtering <i>in</i>.

      * 

      * @param book the book

      * @param in 

      */

     public StrongsNumberFilter(Book book, TokenStream in) {

         super(book, in);

         termAtt = addAttribute(TermAttribute.class);

     }

     /*

      * (non-Javadoc)

      * 

      * @see org.apache.lucene.analysis.TokenStream#incrementToken()

      */

     @Override

     public boolean incrementToken() throws IOException {

         // If the term is suffixed with '!a' or 'a', where 'a' is a sequence of

         // 1 or more letters

         // then create a token without the suffix and also for the whole.

         if (number == null) {

             // Need to loop over invalid tokens

             while (input.incrementToken()) {

                 String tokenText = termAtt.term();

                 number = new StrongsNumber(tokenText);

                 // Skip invalid Strong's Numbers.

                 // Still need to return true as there may be more tokens to filter.

                 if (!number.isValid()) {

                     // TRANSLATOR: User error condition: Indicates that what was given is not a Strong's Number. {0} is a placeholder for the bad Strong's Number.

                     log.warn(JSMsg.gettext("Not a valid Strong's Number \"{0}\"", tokenText));

                     // Go get the next token

                     continue;

                 }

                 String s = number.getStrongsNumber();

                 termAtt.setTermBuffer(s);

                 // If the number had a part keep it around for the next call

                 // TODO(DMS): if there is a part, then treat as a synonym,

                 //      setting the same position increment.

                 if (!number.isPart()) {

                     number = null;

                 }

                 // incrementToken returned a value. There may be more input.

                 return true;

             }

             // There was no more input

             return false;

         }

         // Process the Strong's number with the !a

         termAtt.setTermBuffer(number.getFullStrongsNumber());

         // We are done with the Strong's Number so mark it as used

         number = null;

         // We are working on a value returned by incrementToken.

         // There may be more input.

         return true;

     }

     /* Define to quite FindBugs */

     @Override

     public boolean equals(Object obj) {

         return super.equals(obj);

     }

     /* Define to quite FindBugs */

     @Override

     public int hashCode() {

         return super.hashCode();

     }

     private TermAttribute termAtt;

     private StrongsNumber number;

     /**

      * The log stream

      */

     private static final Logger log = LoggerFactory.getLogger(StrongsNumberFilter.class);

 }