/**

  * 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, 2005 - 2016

  *

  */

 package org.crosswire.jsword.book.filter.thml;

 import java.io.IOException;

 import java.io.StringReader;

 import java.util.List;

 import javax.xml.parsers.ParserConfigurationException;

 import javax.xml.parsers.SAXParser;

 import javax.xml.parsers.SAXParserFactory;

 import org.crosswire.common.xml.XMLUtil;

 import org.crosswire.jsword.book.Book;

 import org.crosswire.jsword.book.OSISUtil;

 import org.crosswire.jsword.book.filter.SourceFilter;

 import org.crosswire.jsword.passage.Key;

 import org.jdom2.Content;

 import org.jdom2.Element;

 import org.slf4j.Logger;

 import org.slf4j.LoggerFactory;

 import org.xml.sax.InputSource;

 import org.xml.sax.SAXException;

 import org.xml.sax.SAXParseException;

 /**

  * Filter to convert THML to OSIS format.

  *

  * <p>

  * I used the THML ref page: <a

  * href="http://www.ccel.org/ThML/ThML1.04.htm">http

  * ://www.ccel.org/ThML/ThML1.04.htm</a> to work out what the tags meant.

  *

  * LATER(joe): check nesting on these THML elements

  *

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

  * @author Joe Walker

  */

 public class THMLFilter implements SourceFilter {

     /* (non-Javadoc)

      * @see org.crosswire.jsword.book.filter.Filter#toOSIS(org.crosswire.jsword.book.Book, org.crosswire.jsword.passage.Key, java.lang.String)

      */

     public List<Content> toOSIS(Book book, Key key, String plain) {

         Element ele = cleanParse(book, key, plain);

         if (ele == null) {

             if (error instanceof SAXParseException) {

                 SAXParseException spe = (SAXParseException) error;

                 int colNumber = spe.getColumnNumber();

                 int start = Math.max(0, colNumber - 40);

                 int stop = Math.min(finalInput.length(), colNumber + 40);

                 int here = stop - start;

                 log.warn("Could not fix {}({}) by {}: Error here({},{},{}): {}",

                          book.getInitials(),

                          key.getName(),

                          errorMessage,

                          Integer.toString(colNumber),

                          Integer.toString(finalInput.length()),

                          Integer.toString(here),

                          finalInput.substring(start, stop));

             } else {

                 log.warn("Could not fix {}({}) by {}: {}",

                          book.getInitials(),

                          key.getName(),

                          errorMessage,

                          error.getMessage());

             }

             ele = OSISUtil.factory().createP();

         }

         return ele.removeContent();

     }

     @Override

     public THMLFilter clone() {

         THMLFilter clone = null;

         try {

             clone = (THMLFilter) super.clone();

         } catch (CloneNotSupportedException e) {

             assert false : e;

         }

         return clone;

     }

     private Element cleanParse(Book book, Key key, String plain) {

         // So just try to strip out all XML looking things

         String clean = XMLUtil.cleanAllEntities(plain);

         Element ele = parse(book, key, clean, "cleaning entities");

         if (ele == null) {

             ele = cleanText(book, key, clean);

         }

         return ele;

     }

     private Element cleanText(Book book, Key key, String plain) {

         // So just try to strip out all XML looking things

         String clean = XMLUtil.cleanAllCharacters(plain);

         Element ele = parse(book, key, clean, "cleaning text");

         if (ele == null) {

             ele = parse(book, key, XMLUtil.closeEmptyTags(clean), "closing empty tags");

         }

         if (ele == null) {

             ele = cleanTags(book, key, clean);

         }

         return ele;

     }

     private Element cleanTags(Book book, Key key, String plain) {

         // So just try to strip out all XML looking things

         String clean = XMLUtil.cleanAllTags(plain);

         return parse(book, key, clean, "cleaning tags");

     }

     private Element parse(Book book, Key key, String plain, String failMessage) {

         Exception ex = null;

         // We need to create a root element to house our document fragment

         // 15 for the tags we add

         StringBuilder buf = new StringBuilder(15 + plain.length());

         buf.append('<').append(RootTag.TAG_ROOT).append('>').append(plain).append("</").append(RootTag.TAG_ROOT).append('>');

         finalInput = buf.toString();

         try {

             StringReader in = new StringReader(finalInput);

             InputSource is = new InputSource(in);

             SAXParserFactory spf = SAXParserFactory.newInstance();

             SAXParser parser = spf.newSAXParser();

             CustomHandler handler = new CustomHandler(book, key);

             parser.parse(is, handler);

             return handler.getRootElement();

         } catch (SAXParseException e) {

             ex = e;

         } catch (SAXException e) {

             ex = e;

         } catch (IOException e) {

             ex = e;

         } catch (ParserConfigurationException e) {

             ex = e;

         } catch (IllegalArgumentException e) {

             // JDOM has a few exceptions which are all derived from this.

             ex = e;

         }

         errorMessage = failMessage;

         error = ex;

         return null;

     }

     private String errorMessage;

     private Exception error;

     private String finalInput;

     /**

      * The log stream

      */

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

 }