package org.apache.maven.doxia.module.fo;
   
   /*
    * 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.
   */
  
  import java.io.File;
  import java.io.IOException;
  import java.io.PrintWriter;
  import java.io.StringWriter;
  import java.io.Writer;
  import java.util.ArrayList;
  import java.util.Enumeration;
  import java.util.HashMap;
  import java.util.LinkedList;
  import java.util.List;
  import java.util.Map;
  import java.util.Set;
  import java.util.Stack;
  import java.util.TreeSet;
  
  import javax.swing.text.MutableAttributeSet;
  import javax.swing.text.html.HTML.Attribute;
  import javax.swing.text.html.HTML.Tag;
  
  import org.apache.maven.doxia.sink.SinkEventAttributes;
  import org.apache.maven.doxia.sink.impl.AbstractXmlSink;
  import org.apache.maven.doxia.sink.impl.SinkEventAttributeSet;
  import org.apache.maven.doxia.sink.impl.SinkUtils;
  import org.apache.maven.doxia.util.DoxiaUtils;
  import org.apache.maven.doxia.util.HtmlTools;
  
  import org.codehaus.plexus.util.xml.PrettyPrintXMLWriter;
  
  import static org.apache.maven.doxia.util.HtmlTools.escapeHTML;
  
  /**
   * A Doxia Sink that produces a FO model. The usage is similar to the following:
   *
   * <pre>
   * FoSink sink = new FoSink( writer );
   * sink.beginDocument();
   * ...
   * sink.endDocument();
   * </pre>
   *
   * @author ltheussl
   * @since 1.1
   */
  public class FoSink
      extends AbstractXmlSink
      implements FoMarkup
  {
      /** For writing the result. */
      private final PrintWriter out;
  
      /** Used to get the current position in numbered lists. */
      private final Stack<NumberedListItem> listStack;
  
      /** Used to get attributes for a given FO element. */
      private final FoConfiguration config;
  
      /** Counts the current section level. */
      private int section = 0;
  
      /** Counts the current subsection level. */
      private int subsection = 0;
  
      /** Counts the current subsubsection level. */
      private int subsubsection = 0;
  
      /** Verbatim flag. */
      private boolean verbatim;
  
      /** figure flag. */
      private boolean inFigure;
  
      private final String encoding;
  
      private final String languageId;
  
      /** Stack of drawing borders on table cells. */
      private final LinkedList<Boolean> tableGridStack;
  
     /** Stack of alignment int[] of table cells. */
     private final LinkedList<int[]> cellJustifStack;
 
     /** Stack of justification of table cells. */
     private final LinkedList<Boolean> isCellJustifStack;
 
     /** Stack of current table cell. */
     private final LinkedList<Integer> cellCountStack;
 
     /** The stack of StringWriter to write the table result temporary, so we could play with the output and fix fo. */
     private final LinkedList<StringWriter> tableContentWriterStack;
 
     private final LinkedList<StringWriter> tableCaptionWriterStack;
 
     private final LinkedList<PrettyPrintXMLWriter> tableCaptionXMLWriterStack;
 
     /** The stack of table caption */
     private final LinkedList<String> tableCaptionStack;
 
     /** Keep track of the closing tags for inline events. */
     protected Stack<List<Tag>> inlineStack = new Stack<>();
 
     /** Map of warn messages with a String as key to describe the error type and a Set as value.
      * Using to reduce warn messages. */
     protected Map<String, Set<String>> warnMessages;
 
     /**
      * Constructor, initialize the Writer.
      *
      * @param writer not null writer to write the result. <b>Should</b> be an UTF-8 Writer.
      * You could use <code>newXmlWriter</code> methods from {@link org.codehaus.plexus.util.WriterFactory}.
      */
     protected FoSink( Writer writer )
     {
         this( writer, "UTF-8" );
     }
 
     /**
      * Constructor, initialize the Writer and tells which encoding is used.
      *
      * @param writer not null writer to write the result.
      * @param encoding the encoding used, that should be written to the generated HTML content
      * if not <code>null</code>.
      */
     protected FoSink( Writer writer, String encoding )
     {
         this( writer, encoding, null );
     }
 
     /**
      * Constructor, initialize the Writer and tells which encoding and languageId are used.
      *
      * @param writer not null writer to write the result.
      * @param encoding the encoding used, that should be written to the generated HTML content
      * if not <code>null</code>.
      * @param languageId language identifier for the root element as defined by
      * <a href="ftp://ftp.isi.edu/in-notes/bcp/bcp47.txt">IETF BCP 47</a>, Tags for the Identification of Languages;
      * in addition, the empty string may be specified.
      */
     protected FoSink( Writer writer, String encoding, String languageId )
     {
         if ( writer == null )
         {
             throw new NullPointerException( "Null writer in FO Sink!" );
         }
 
         this.out = new PrintWriter( writer );
         this.encoding = encoding;
         this.languageId = languageId;
         this.config = new FoConfiguration();
 
         this.listStack = new Stack<>();
         this.tableGridStack = new LinkedList<>();
         this.cellJustifStack = new LinkedList<>();
         this.isCellJustifStack = new LinkedList<>();
         this.cellCountStack = new LinkedList<>();
         this.tableContentWriterStack = new LinkedList<>();
         this.tableCaptionWriterStack = new LinkedList<>();
         this.tableCaptionXMLWriterStack = new LinkedList<>();
         this.tableCaptionStack = new LinkedList<>();
 
         setNameSpace( "fo" );
     }
 
     // TODO add FOP compliance mode?
 
     /**
      * Load configuration parameters from a File.
      *
      * @param configFile the configuration file.
      *
      * @throws java.io.IOException if the File cannot be read
      *  or some error occurs when initializing the configuration parameters.
      *
      * @since 1.1.1
      */
     public void load( File configFile )
             throws IOException
     {
         config.load( configFile );
     }
 
     /** {@inheritDoc} */
     public void head( SinkEventAttributes attributes )
     {
         init();
 
         startPageSequence( "0", null, null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void head()
     {
         head( null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void head_()
     {
         writeEOL();
     }
 
     /** {@inheritDoc} */
     public void title( SinkEventAttributes attributes )
     {
         writeStartTag( BLOCK_TAG, "doc.header.title" );
     }
 
     /**
      * {@inheritDoc}
      */
     public void title()
     {
         title( null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void title_()
     {
         writeEndTag( BLOCK_TAG );
         writeEOL();
     }
 
     /** {@inheritDoc} */
     public void author( SinkEventAttributes attributes )
     {
         writeStartTag( BLOCK_TAG, "doc.header.author" );
     }
 
     /**
      * {@inheritDoc}
      */
     public void author()
     {
         author( null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void author_()
     {
         writeEndTag( BLOCK_TAG );
         writeEOL();
     }
 
     /** {@inheritDoc} */
     public void date( SinkEventAttributes attributes )
     {
         writeStartTag( BLOCK_TAG, "doc.header.date" );
     }
 
     /**
      * {@inheritDoc}
      */
     public void date()
     {
         date( null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void date_()
     {
         writeEndTag( BLOCK_TAG );
         writeEOL();
     }
 
     /** {@inheritDoc} */
     public void body( SinkEventAttributes attributes )
     {
         // noop
     }
 
     /**
      * {@inheritDoc}
      */
     public void body()
     {
         body( null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void body_()
     {
         writeEOL();
         writeEndTag( FLOW_TAG );
         writeEOL();
         writeEndTag( PAGE_SEQUENCE_TAG );
         writeEOL();
         endDocument();
     }
 
     // -----------------------------------------------------------------------
     //
     // -----------------------------------------------------------------------
 
     /**
      * {@inheritDoc}
      */
     public void sectionTitle()
     {
         // nop
     }
 
     /**
      * {@inheritDoc}
      */
     public void sectionTitle_()
     {
         // nop
     }
 
     /** {@inheritDoc} */
     public void section( int level, SinkEventAttributes attributes )
     {
         if ( level == SECTION_LEVEL_1 )
         {
             section++;
             subsection = 0;
             subsubsection = 0;
         }
         else if ( level == SECTION_LEVEL_2 )
         {
             subsection++;
             subsubsection = 0;
         }
         else if ( level == SECTION_LEVEL_3 )
         {
             subsubsection++;
         }
 
         onSection();
     }
 
     /** {@inheritDoc} */
     public void section_( int level )
     {
         onSection_();
     }
 
     /** {@inheritDoc} */
     public void sectionTitle( int level, SinkEventAttributes attributes )
     {
         onSectionTitle( level );
     }
 
     /** {@inheritDoc} */
     public void sectionTitle_( int level )
     {
         onSectionTitle_();
     }
 
     /**
      * {@inheritDoc}
      */
     public void section1()
     {
         section( SECTION_LEVEL_1, null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void sectionTitle1()
     {
         sectionTitle( SECTION_LEVEL_1, null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void sectionTitle1_()
     {
         sectionTitle_( SECTION_LEVEL_1 );
     }
 
     /**
      * {@inheritDoc}
      */
     public void section1_()
     {
         section_( SECTION_LEVEL_1 );
     }
 
     /**
      * {@inheritDoc}
      */
     public void section2()
     {
         section( SECTION_LEVEL_2, null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void sectionTitle2()
     {
         sectionTitle( SECTION_LEVEL_2, null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void sectionTitle2_()
     {
         sectionTitle_( SECTION_LEVEL_2 );
     }
 
     /**
      * {@inheritDoc}
      */
     public void section2_()
     {
         section_( SECTION_LEVEL_2 );
     }
 
     /**
      * {@inheritDoc}
      */
     public void section3()
     {
         section( SECTION_LEVEL_3, null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void sectionTitle3()
     {
         sectionTitle( SECTION_LEVEL_3, null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void sectionTitle3_()
     {
         sectionTitle_( SECTION_LEVEL_3 );
     }
 
     /**
      * {@inheritDoc}
      */
     public void section3_()
     {
         section_( SECTION_LEVEL_3 );
     }
 
     /**
      * {@inheritDoc}
      */
     public void section4()
     {
         section( SECTION_LEVEL_4, null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void sectionTitle4()
     {
         sectionTitle( SECTION_LEVEL_4, null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void sectionTitle4_()
     {
         sectionTitle_( SECTION_LEVEL_4 );
     }
 
     /**
      * {@inheritDoc}
      */
     public void section4_()
     {
         section_( SECTION_LEVEL_4 );
     }
 
     /**
      * {@inheritDoc}
      */
     public void section5()
     {
         section( SECTION_LEVEL_5, null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void sectionTitle5()
     {
         sectionTitle( SECTION_LEVEL_5, null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void sectionTitle5_()
     {
         sectionTitle_( SECTION_LEVEL_5 );
     }
 
     /**
      * {@inheritDoc}
      */
     public void section5_()
     {
         section_( SECTION_LEVEL_5 );
     }
 
     /** Starts a section/subsection. */
     private void onSection()
     {
         writeEOL();
         writeStartTag( BLOCK_TAG, "body.text" );
     }
 
     /**
      * Starts a section title.
      *
      * @param depth The section level.
      */
     private void onSectionTitle( int depth )
     {
         StringBuilder title = new StringBuilder( 16 );
 
         title.append( getChapterString() );
 
         writeEOL();
         if ( depth == SECTION_LEVEL_1 )
         {
             writeStartTag( BLOCK_TAG, "body.h1" );
             title.append( section ).append( "   " );
         }
         else if ( depth == SECTION_LEVEL_2 )
         {
             writeStartTag( BLOCK_TAG, "body.h2" );
             title.append( section ).append( "." );
             title.append( subsection ).append( "   " );
         }
         else if ( depth == SECTION_LEVEL_3 )
         {
             writeStartTag( BLOCK_TAG, "body.h3" );
             title.append( section ).append( "." );
             title.append( subsection ).append( "." );
             title.append( subsubsection ).append( "   " );
         }
         else if ( depth == SECTION_LEVEL_4 )
         {
             writeStartTag( BLOCK_TAG, "body.h4" );
         }
         else
         {
             writeStartTag( BLOCK_TAG, "body.h5" );
         }
 
         write( title.toString() );
     }
 
     /** Ends a section title. */
     private void onSectionTitle_()
     {
         writeEndTag( BLOCK_TAG );
         writeEOL();
     }
 
     /** Ends a section/subsection. */
     private void onSection_()
     {
         writeEndTag( BLOCK_TAG );
         writeEOL();
     }
 
     /**
      * Resets the section counter to 0.
      * Only useful for overriding classes, like AggregateSink, the FoSink puts everything into one chapter.
      */
     protected void resetSectionCounter()
     {
         this.section = 0;
     }
 
     /**
      * Returns the current chapter number as a string.
      * By default does nothing, gets overridden by AggregateSink.
      *
      * @return an empty String.
      */
     protected String getChapterString()
     {
         return "";
     }
 
     // -----------------------------------------------------------------------
     //
     // -----------------------------------------------------------------------
 
     /** {@inheritDoc} */
     public void list( SinkEventAttributes attributes )
     {
         writeEOL();
         writeStartTag( LIST_BLOCK_TAG, "list" );
     }
 
     /**
      * {@inheritDoc}
      */
     public void list()
     {
         list( null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void list_()
     {
         writeEndTag( LIST_BLOCK_TAG );
         writeEOL();
     }
 
     /** {@inheritDoc} */
     public void listItem( SinkEventAttributes attributes )
     {
         writeStartTag( LIST_ITEM_TAG, "list.item" );
         writeStartTag( LIST_ITEM_LABEL_TAG );
         writeStartTag( BLOCK_TAG );
         write( "&#8226;" ); // TODO customize?
         writeEndTag( BLOCK_TAG );
         writeEndTag( LIST_ITEM_LABEL_TAG );
         writeEOL();
         writeStartTag( LIST_ITEM_BODY_TAG, "list.item" );
         writeEOL();
         writeStartTag( BLOCK_TAG );
     }
 
     /**
      * {@inheritDoc}
      */
     public void listItem()
     {
         listItem( null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void listItem_()
     {
         writeEndTag( BLOCK_TAG );
         writeEOL();
         writeEndTag( LIST_ITEM_BODY_TAG );
         writeEOL();
         writeEndTag( LIST_ITEM_TAG );
         writeEOL();
     }
 
     /** {@inheritDoc} */
     public void numberedList( int numbering, SinkEventAttributes attributes )
     {
         this.listStack.push( new NumberedListItem( numbering ) );
         writeEOL();
         writeStartTag( LIST_BLOCK_TAG, "list" );
     }
 
     /** {@inheritDoc} */
     public void numberedList( int numbering )
     {
         numberedList( numbering, null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void numberedList_()
     {
         this.listStack.pop();
         writeEndTag( LIST_BLOCK_TAG );
         writeEOL();
     }
 
     /** {@inheritDoc} */
     public void numberedListItem( SinkEventAttributes attributes )
     {
         NumberedListItem current = this.listStack.peek();
         current.next();
 
         writeStartTag( LIST_ITEM_TAG, "list.item" );
 
         writeEOL();
         writeStartTag( LIST_ITEM_LABEL_TAG );
         writeEOL();
         writeStartTag( BLOCK_TAG );
         write( current.getListItemSymbol() );
         writeEndTag( BLOCK_TAG );
         writeEOL();
         writeEndTag( LIST_ITEM_LABEL_TAG );
         writeEOL();
 
         writeStartTag( LIST_ITEM_BODY_TAG, "list.item" );
         writeEOL();
         writeStartTag( BLOCK_TAG );
     }
 
     /**
      * {@inheritDoc}
      */
     public void numberedListItem()
     {
         numberedListItem( null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void numberedListItem_()
     {
         writeEndTag( BLOCK_TAG );
         writeEOL();
         writeEndTag( LIST_ITEM_BODY_TAG );
         writeEOL();
         writeEndTag( LIST_ITEM_TAG );
         writeEOL();
     }
 
     /** {@inheritDoc} */
     public void definitionList( SinkEventAttributes attributes )
     {
         writeEOL();
         writeStartTag( BLOCK_TAG, "dl" );
     }
 
     /**
      * {@inheritDoc}
      */
     public void definitionList()
     {
         definitionList( null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void definitionList_()
     {
         writeEndTag( BLOCK_TAG );
         writeEOL();
     }
 
     /** {@inheritDoc} */
     public void definitionListItem( SinkEventAttributes attributes )
     {
         // nop
     }
 
     /**
      * {@inheritDoc}
      */
     public void definitionListItem()
     {
         definitionListItem( null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void definitionListItem_()
     {
         // nop
     }
 
     /** {@inheritDoc} */
     public void definedTerm( SinkEventAttributes attributes )
     {
         writeStartTag( BLOCK_TAG, "dt" );
     }
 
     /**
      * {@inheritDoc}
      */
     public void definedTerm()
     {
         definedTerm( null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void definedTerm_()
     {
         writeEndTag( BLOCK_TAG );
         writeEOL();
     }
 
     /** {@inheritDoc} */
     public void definition( SinkEventAttributes attributes )
     {
         writeEOL();
         writeStartTag( BLOCK_TAG, "dd" );
     }
 
     /**
      * {@inheritDoc}
      */
     public void definition()
     {
         definition( null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void definition_()
     {
         writeEndTag( BLOCK_TAG );
         writeEOL();
     }
 
     /** {@inheritDoc} */
     public void figure( SinkEventAttributes attributes )
     {
         this.inFigure = true;
         writeEOL();
         writeStartTag( BLOCK_TAG, "figure.display" );
     }
 
     /**
      * {@inheritDoc}
      */
     public void figure()
     {
         figure( null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void figure_()
     {
         this.inFigure = false;
         writeEndTag( BLOCK_TAG );
         writeEOL();
     }
 
     /** {@inheritDoc} */
     public void figureGraphics( String name )
     {
         figureGraphics( name, null );
     }
 
     /** {@inheritDoc} */
     public void figureGraphics( String src, SinkEventAttributes attributes )
     {
         MutableAttributeSet atts = config.getAttributeSet( "figure.graphics" );
         atts.addAttribute( Attribute.SRC.toString(), escapeHTML( src ) );
 
         // https://xmlgraphics.apache.org/fop/trunk/graphics.html#resolution
 
         final String[] valids = new String[] {"content-height", "content-width", "height", "width"};
         final MutableAttributeSet filtered = SinkUtils.filterAttributes( attributes, valids );
 
         if ( filtered != null )
         {
             atts.addAttributes( filtered );
         }
 
         writeln( "<fo:external-graphic" + SinkUtils.getAttributeString( atts ) + "/>" );
     }
 
     /**
      * Flags if we are inside a figure.
      *
      * @return True if we are between {@link #figure()} and {@link #figure_()} calls.
      */
     protected boolean isFigure()
     {
         return this.inFigure;
     }
 
     /** {@inheritDoc} */
     public void figureCaption( SinkEventAttributes attributes )
     {
         writeStartTag( BLOCK_TAG, "figure.caption" );
     }
 
     /**
      * {@inheritDoc}
      */
     public void figureCaption()
     {
         figureCaption( null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void figureCaption_()
     {
         writeEndTag( BLOCK_TAG );
         writeEOL();
     }
 
     /**
      * {@inheritDoc}
      */
     public void paragraph()
     {
         paragraph( null );
     }
 
     /** {@inheritDoc} */
     public void paragraph( SinkEventAttributes attributes )
     {
         MutableAttributeSet atts = config.getAttributeSet( "normal.paragraph" );
 
         if ( attributes != null && attributes.isDefined( SinkEventAttributes.ALIGN ) )
         {
             atts.addAttribute( "text-align", attributes.getAttribute( SinkEventAttributes.ALIGN ) );
         }
 
         writeEOL();
         writeStartTag( BLOCK_TAG, atts );
     }
 
     /**
      * {@inheritDoc}
      */
     public void paragraph_()
     {
         writeEndTag( BLOCK_TAG );
         writeEOL();
     }
 
     /**
      * {@inheritDoc}
      *
      * @param attributes a {@link org.apache.maven.doxia.sink.SinkEventAttributes} object.
      */
     public void verbatim( SinkEventAttributes attributes )
     {
         this.verbatim = true;
 
         boolean boxed = false;
 
         if ( attributes != null && attributes.isDefined( SinkEventAttributes.DECORATION ) )
         {
             boxed =
                 "boxed".equals( attributes.getAttribute( SinkEventAttributes.DECORATION ).toString() );
         }
 
         if ( boxed )
         {
             writeStartTag( BLOCK_TAG, "body.source" );
         }
         else
         {
             writeStartTag( BLOCK_TAG, "body.pre" );
         }
     }
 
     /** {@inheritDoc} */
     public void verbatim( boolean boxed )
     {
         verbatim( boxed ? SinkEventAttributeSet.BOXED : null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void verbatim_()
     {
         this.verbatim = false;
         writeEndTag( BLOCK_TAG );
         writeEOL();
     }
 
     /** {@inheritDoc} */
     public void horizontalRule( SinkEventAttributes attributes )
     {
         writeEOL();
         writeEOL();
         writeStartTag( BLOCK_TAG );
         writeEmptyTag( LEADER_TAG, "body.rule" );
         writeEndTag( BLOCK_TAG );
         writeEOL();
     }
 
     /**
      * {@inheritDoc}
      */
     public void horizontalRule()
     {
         horizontalRule( null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void pageBreak()
     {
         writeEmptyTag( BLOCK_TAG, "break-before", "page" );
         writeEOL();
     }
 
     /** {@inheritDoc} */
     public void table( SinkEventAttributes attributes )
     {
         writeEOL();
         writeStartTag( BLOCK_TAG, "table.padding" );
 
         // <fo:table-and-caption> is XSL-FO 1.0 standard but still not implemented in FOP 0.95
         //writeStartTag( TABLE_AND_CAPTION_TAG );
 
         this.tableContentWriterStack.addLast( new StringWriter() );
         writeStartTag( TABLE_TAG, "table.layout" );
     }
 
     /**
      * {@inheritDoc}
      */
     public void table()
     {
         table( null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void table_()
     {
         String content = this.tableContentWriterStack.removeLast().toString();
 
         StringBuilder sb = new StringBuilder();
         int cellCount = Integer.parseInt( this.cellCountStack.removeLast().toString() );
         for ( int i = 0; i < cellCount; i++ )
         {
             sb.append( "<fo:table-column column-width=\"proportional-column-width(1)\"/>" );
             sb.append( EOL );
         }
 
         int index = content.indexOf( ">" ) + 1;
         writeln( content.substring( 0, index ) );
         write( sb.toString() );
         write( content.substring( index ) );
 
         writeEndTag( TABLE_TAG );
         writeEOL();
 
         // <fo:table-and-caption> is XSL-FO 1.0 standard but still not implemented in FOP 0.95
         //writeEndTag( TABLE_AND_CAPTION_TAG );
 
         writeEndTag( BLOCK_TAG );
         writeEOL();
 
         if ( !this.tableCaptionStack.isEmpty() && this.tableCaptionStack.getLast() != null )
         {
             paragraph( SinkEventAttributeSet.CENTER );
             write( this.tableCaptionStack.removeLast() );
             paragraph_();
         }
     }
 
     /** {@inheritDoc} */
     public void tableRows( int[] justification, boolean grid )
     {
         this.tableGridStack.addLast( grid );
         this.cellJustifStack.addLast( justification );
         this.isCellJustifStack.addLast( Boolean.TRUE );
         this.cellCountStack.addLast( 0 );
         writeEOL();
         writeStartTag( TABLE_BODY_TAG );
     }
 
     /**
      * {@inheritDoc}
      */
     public void tableRows_()
     {
         this.tableGridStack.removeLast();
         this.cellJustifStack.removeLast();
         this.isCellJustifStack.removeLast();
         writeEndTag( TABLE_BODY_TAG );
         writeEOL();
     }
 
     /** {@inheritDoc} */
     public void tableRow( SinkEventAttributes attributes )
     {
         // TODO spacer rows
         writeStartTag( TABLE_ROW_TAG, "table.body.row" );
         this.cellCountStack.removeLast();
         this.cellCountStack.addLast( 0 );
     }
 
     /**
      * {@inheritDoc}
      */
     public void tableRow()
     {
         tableRow( null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void tableRow_()
     {
         writeEndTag( TABLE_ROW_TAG );
         writeEOL();
     }
 
     /** {@inheritDoc} */
     public void tableCell( SinkEventAttributes attributes )
     {
         tableCell( false, attributes );
     }
 
     /**
      * {@inheritDoc}
      */
     public void tableCell()
     {
         tableCell( (SinkEventAttributes) null );
     }
 
     /** {@inheritDoc} */
     public void tableCell( String width )
     {
         // TODO: fop can't handle cell width
         tableCell();
     }
 
     /** {@inheritDoc} */
     public void tableHeaderCell( SinkEventAttributes attributes )
     {
         tableCell( true, attributes );
     }
 
     /**
      * {@inheritDoc}
      */
     public void tableHeaderCell()
     {
         tableHeaderCell( (SinkEventAttributes) null );
     }
 
     /** {@inheritDoc} */
     public void tableHeaderCell( String width )
     {
         // TODO: fop can't handle cell width
         tableHeaderCell();
     }
 
     /**
      * Writes a table cell.
      *
      * @param headerRow true if this is a header cell.
      * @param attributes the cell attributes, could be null.
      */
     private void tableCell( boolean headerRow, SinkEventAttributes attributes )
     {
         MutableAttributeSet cellAtts = headerRow
                  ? config.getAttributeSet( "table.heading.cell" )
                  : config.getAttributeSet( "table.body.cell" );
 
         // the column-number is needed for the hack to center the table, see tableRows.
         int cellCount = Integer.parseInt( this.cellCountStack.getLast().toString() );
         cellAtts.addAttribute( "column-number", String.valueOf( cellCount + 1 ) );
 
         if ( this.tableGridStack.getLast().equals( Boolean.TRUE ) )
         {
             cellAtts.addAttributes( config.getAttributeSet( "table.body.cell.grid" ) );
         }
 
         MutableAttributeSet blockAtts = headerRow
                  ? config.getAttributeSet( "table.heading.block" )
                  : config.getAttributeSet( "table.body.block" );
 
         String justif = null;
         if ( attributes == null )
         {
             attributes = new SinkEventAttributeSet( 0 );
         }
 
         if ( attributes.isDefined( Attribute.ALIGN.toString() ) )
         {
             justif = attributes.getAttribute( Attribute.ALIGN.toString() ).toString();
         }
 
         int[] cellJustif = this.cellJustifStack.getLast();
         if ( justif == null && cellJustif != null && cellJustif.length > 0
             && this.isCellJustifStack.getLast().equals( Boolean.TRUE ) )
         {
             switch ( cellJustif[Math.min( cellCount, cellJustif.length - 1 )] )
             {
                 case JUSTIFY_LEFT:
                     justif = "left";
                     break;
                 case JUSTIFY_RIGHT:
                     justif = "right";
                     break;
                 case JUSTIFY_CENTER:
                 default:
                     justif = "center";
             }
         }
 
         if ( justif != null )
         {
             blockAtts.addAttribute( "text-align", justif );
         }
 
         writeStartTag( TABLE_CELL_TAG, cellAtts );
         writeEOL();
         writeStartTag( BLOCK_TAG, blockAtts );
         writeEOL();
     }
 
     /**
      * {@inheritDoc}
      */
     public void tableCell_()
     {
         writeEndTag( BLOCK_TAG );
         writeEOL();
         writeEndTag( TABLE_CELL_TAG );
         writeEOL();
 
         if ( this.isCellJustifStack.getLast().equals( Boolean.TRUE ) )
         {
             int cellCount = Integer.parseInt( this.cellCountStack.removeLast().toString() );
             this.cellCountStack.addLast( ++cellCount );
         }
     }
 
     /**
      * {@inheritDoc}
      */
     public void tableHeaderCell_()
     {
         tableCell_();
     }
 
     /** {@inheritDoc} */
     public void tableCaption( SinkEventAttributes attributes )
     {
         StringWriter sw = new StringWriter();
         this.tableCaptionWriterStack.addLast( sw );
         this.tableCaptionXMLWriterStack.addLast( new PrettyPrintXMLWriter( sw ) );
 
         // <fo:table-caption> is XSL-FO 1.0 standard but not implemented in FOP 0.95
         //writeStartTag( TABLE_CAPTION_TAG );
 
         // TODO: how to implement this otherwise?
         // table-footer doesn't work because it has to be declared before table-body.
     }
 
     /**
      * {@inheritDoc}
      */
     public void tableCaption()
     {
         tableCaption( null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void tableCaption_()
     {
         if ( !this.tableCaptionXMLWriterStack.isEmpty() && this.tableCaptionXMLWriterStack.getLast() != null )
         {
             this.tableCaptionStack.addLast( this.tableCaptionWriterStack.removeLast().toString() );
             this.tableCaptionXMLWriterStack.removeLast();
         }
         // <fo:table-caption> is XSL-FO 1.0 standard but not implemented in FOP 0.95
         //writeEndTag( TABLE_CAPTION_TAG );
     }
 
     /** {@inheritDoc} */
     public void anchor( String name, SinkEventAttributes attributes )
     {
         if ( name == null )
         {
             throw new NullPointerException( "Anchor name cannot be null!" );
         }
 
         String anchor = name;
 
         if ( !DoxiaUtils.isValidId( anchor ) )
         {
             anchor = DoxiaUtils.encodeId( name, true );
 
             String msg = "Modified invalid anchor name: '" + name + "' to '" + anchor + "'";
             logMessage( "modifiedLink", msg );
         }
 
         anchor = "#" + name;
 
         writeStartTag( INLINE_TAG, "id", anchor );
     }
 
     /** {@inheritDoc} */
     public void anchor( String name )
     {
         anchor( name, null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void anchor_()
     {
         writeEndTag( INLINE_TAG );
     }
 
     /** {@inheritDoc} */
     public void link( String name, SinkEventAttributes attributes )
     {
         if ( name == null )
         {
             throw new NullPointerException( "Link name cannot be null!" );
         }
 
         if ( DoxiaUtils.isExternalLink( name ) )
         {
             writeStartTag( BASIC_LINK_TAG, "external-destination", HtmlTools.escapeHTML( name ) );
             writeStartTag( INLINE_TAG, "href.external" );
         }
         else if ( DoxiaUtils.isInternalLink( name ) )
         {
             String anchor = name.substring( 1 );
 
             if ( !DoxiaUtils.isValidId( anchor ) )
             {
                 anchor = DoxiaUtils.encodeId( anchor, true );
 
                 String msg = "Modified invalid anchor name: '" + name + "' to '" + anchor + "'";
                 logMessage( "modifiedLink", msg );
             }
 
             anchor = "#" + anchor;
 
             writeStartTag( BASIC_LINK_TAG, "internal-destination", HtmlTools.escapeHTML( anchor ) );
             writeStartTag( INLINE_TAG, "href.internal" );
         }
         else
         {
             // treat everything else as is
             writeStartTag( BASIC_LINK_TAG, "internal-destination", HtmlTools.escapeHTML( name ) );
             writeStartTag( INLINE_TAG, "href.internal" );
         }
     }
 
     /** {@inheritDoc} */
     public void link( String name )
     {
         link( name, null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void link_()
     {
         writeEndTag( INLINE_TAG );
         writeEndTag( BASIC_LINK_TAG );
     }
 
     /**
      * {@inheritDoc}
      */
     public void inline()
     {
         inline( null );
     }
 
     /** {@inheritDoc} */
     public void inline( SinkEventAttributes attributes )
     {
         List<Tag> tags = new ArrayList<>();
 
         if ( attributes != null )
         {
 
             if ( attributes.containsAttribute( SinkEventAttributes.SEMANTICS, "italic" ) )
             {
                 writeStartTag( INLINE_TAG, "italic" );
                 tags.add( 0, INLINE_TAG );
             }
 
             if ( attributes.containsAttribute( SinkEventAttributes.SEMANTICS, "bold" ) )
             {
                 writeStartTag( INLINE_TAG, "bold" );
                 tags.add( 0, INLINE_TAG );
             }
 
             if ( attributes.containsAttribute( SinkEventAttributes.SEMANTICS, "code" ) )
             {
                 writeStartTag( INLINE_TAG, "monospace" );
                 tags.add( 0, INLINE_TAG );
             }
 
         }
 
         inlineStack.push( tags );
     }
 
     /**
      * {@inheritDoc}
      */
     public void inline_()
     {
         for ( Tag tag: inlineStack.pop() )
         {
             writeEndTag( tag );
         }
     }
 
     /**
      * {@inheritDoc}
      */
     public void italic()
     {
         inline( SinkEventAttributeSet.Semantics.ITALIC );
     }
 
     /**
      * {@inheritDoc}
      */
     public void italic_()
     {
         inline_();
     }
 
     /**
      * {@inheritDoc}
      */
     public void bold()
     {
         inline( SinkEventAttributeSet.Semantics.BOLD );
     }
 
     /**
      * {@inheritDoc}
      */
     public void bold_()
     {
         inline_();
     }
 
     /**
      * {@inheritDoc}
      */
     public void monospaced()
     {
         inline( SinkEventAttributeSet.Semantics.CODE );
     }
 
     /**
      * {@inheritDoc}
      */
     public void monospaced_()
     {
         inline_();
     }
 
     /** {@inheritDoc} */
     public void lineBreak( SinkEventAttributes attributes )
     {
         writeEOL();
         writeEOL();
         writeSimpleTag( BLOCK_TAG );
     }
 
     /**
      * {@inheritDoc}
      */
     public void lineBreak()
     {
         lineBreak( null );
     }
 
     /**
      * {@inheritDoc}
      */
     public void nonBreakingSpace()
     {
         write( "&#160;" );
     }
 
     /** {@inheritDoc} */
     public void text( String text, SinkEventAttributes attributes )
     {
         content( text );
     }
 
     /** {@inheritDoc} */
     public void text( String text )
     {
         text( text, null );
     }
 
     /** {@inheritDoc} */
     public void rawText( String text )
     {
         write( text );
     }
 
     /**
      * {@inheritDoc}
      */
     public void flush()
     {
         out.flush();
     }
 
     /**
      * {@inheritDoc}
      */
     public void close()
     {
         out.close();
 
         if ( getLog().isWarnEnabled() && this.warnMessages != null )
         {
             for ( Map.Entry<String, Set<String>> entry : this.warnMessages.entrySet() )
             {
                 for ( String msg : entry.getValue() )
                 {
                     getLog().warn( msg );
                 }
             }
 
             this.warnMessages = null;
         }
 
         init();
     }
 
     /**
      * {@inheritDoc}
      *
      * Unkown events just log a warning message but are ignored otherwise.
      * @see org.apache.maven.doxia.sink.Sink#unknown(String,Object[],SinkEventAttributes)
      */
     public void unknown( String name, Object[] requiredParams, SinkEventAttributes attributes )
     {
         String msg = "Unknown Sink event: '" + name + "', ignoring!";
         logMessage( "unknownEvent", msg );
     }
 
     /** {@inheritDoc} */
     public void comment( String comment )
     {
         if ( comment != null )
         {
             final String originalComment = comment;
 
             // http://www.w3.org/TR/2000/REC-xml-20001006#sec-comments
             while ( comment.contains( "--" ) )
             {
                 comment = comment.replace( "--", "- -" );
             }
 
             if ( comment.endsWith( "-" ) )
             {
                 comment += " ";
             }
 
             if ( !originalComment.equals( comment ) )
             {
                 String msg = "Modified invalid comment: '" + originalComment + "' to '" + comment + "'";
                 logMessage( "modifyComment", msg );
             }
 
             final StringBuilder buffer = new StringBuilder( comment.length() + 7 );
 
             buffer.append( LESS_THAN ).append( BANG ).append( MINUS ).append( MINUS );
             buffer.append( comment );
             buffer.append( MINUS ).append( MINUS ).append( GREATER_THAN );
 
             write( buffer.toString() );
         }
     }
 
     /**
      * Writes the beginning of a FO document.
      */
     public void beginDocument()
     {
         write( "<?xml version=\"1.0\"" );
         if ( encoding != null )
         {
             write( " encoding=\"" + encoding + "\"" );
         }
         write( "?>" );
         writeEOL();
 
         MutableAttributeSet atts = new SinkEventAttributeSet();
         atts.addAttribute( "xmlns:" + getNameSpace(), FO_NAMESPACE );
 
         if ( languageId != null )
         {
             atts.addAttribute( "language", languageId );
         }
 
         writeStartTag( ROOT_TAG, atts );
 
         writeStartTag( LAYOUT_MASTER_SET_TAG );
 
         writeStartTag( SIMPLE_PAGE_MASTER_TAG, "layout.master.set.cover-page" );
         writeEmptyTag( REGION_BODY_TAG, "layout.master.set.cover-page.region-body" );
         writeEndTag( SIMPLE_PAGE_MASTER_TAG );
         writeEOL();
 
         writeStartTag( SIMPLE_PAGE_MASTER_TAG, "layout.master.set.toc" );
         writeEmptyTag( REGION_BODY_TAG, "layout.master.set.toc.region-body" );
         writeEmptyTag( REGION_BEFORE_TAG, "layout.master.set.toc.region-before" );
         writeEmptyTag( REGION_AFTER_TAG, "layout.master.set.toc.region-after" );
         writeEndTag( SIMPLE_PAGE_MASTER_TAG );
         writeEOL();
 
         writeStartTag( SIMPLE_PAGE_MASTER_TAG, "layout.master.set.body" );
         writeEmptyTag( REGION_BODY_TAG, "layout.master.set.body.region-body" );
         writeEmptyTag( REGION_BEFORE_TAG, "layout.master.set.body.region-before" );
         writeEmptyTag( REGION_AFTER_TAG, "layout.master.set.body.region-after" );
         writeEndTag( SIMPLE_PAGE_MASTER_TAG );
         writeEOL();
 
         writeEndTag( LAYOUT_MASTER_SET_TAG );
         writeEOL();
 
         pdfBookmarks();
     }
 
     /**
      * Writes the end of a FO document, flushes and closes the stream.
      */
     public void endDocument()
     {
         writeEndTag( ROOT_TAG );
         writeEOL();
 
         flush();
         close();
     }
 
     // ----------------------------------------------------------------------
     //
     // ----------------------------------------------------------------------
 
     /**
      * Returns the configuration object of this sink.
      *
      * @return The configuration object of this sink.
      */
     protected FoConfiguration getFoConfiguration()
     {
         return config;
     }
 
     /**
      * Writes a start tag, prepending EOL.
      *
      * @param tag The tag.
      * @param attributeId An id identifying the attribute set.
      */
     protected void writeStartTag( Tag tag, String attributeId )
     {
         writeEOL();
         writeStartTag( tag, config.getAttributeSet( attributeId ) );
     }
 
     /**
      * Writes a start tag, prepending EOL.
      *
      * @param tag The tag.
      * @param id An id to add.
      * @param name The name (value) of the id.
      */
     protected void writeStartTag( Tag tag, String id, String name )
     {
         writeEOL();
         MutableAttributeSet att = new SinkEventAttributeSet( id, name );
 
         writeStartTag( tag, att );
     }
 
     /**
      * Writes a start tag, prepending EOL.
      *
      * @param tag The tag.
      * @param id An id to add.
      * @param name The name (value) of the id.
      * @param attributeId An id identifying the attribute set.
      */
     protected void writeStartTag( Tag tag, String id, String name, String attributeId )
     {
         MutableAttributeSet att = config.getAttributeSet( attributeId );
 
         // make sure we don't add it twice
         if ( att.isDefined( id ) )
         {
             att.removeAttribute( id );
         }
 
         att.addAttribute( id, name );
 
         writeEOL();
         writeStartTag( tag, att );
     }
 
     /**
      * Writes an empty tag, prepending EOL.
      *
      * @param tag The tag.
      * @param id An id to add.
      * @param name The name (value) of the id.
      */
     protected void writeEmptyTag( Tag tag, String id, String name )
     {
         MutableAttributeSet att = new SinkEventAttributeSet( id, name );
 
         writeEOL();
         writeSimpleTag( tag, att );
     }
 
     /**
      * Writes a simple tag, appending EOL.
      *
      * @param tag The tag name.
      * @param attributeId An id identifying the attribute set.
      */
     protected void writeEmptyTag( Tag tag, String attributeId )
     {
         writeEOL();
         writeSimpleTag( tag, config.getAttributeSet( attributeId ) );
     }
 
     /**
      * {@inheritDoc}
      *
      * Writes a text, swallowing any exceptions.
      */
     protected void write( String text )
     {
         if ( !this.tableCaptionXMLWriterStack.isEmpty() && this.tableCaptionXMLWriterStack.getLast() != null )
         {
             this.tableCaptionXMLWriterStack.getLast().writeText( unifyEOLs( text ) );
         }
         else if ( !this.tableContentWriterStack.isEmpty() && this.tableContentWriterStack.getLast() != null )
         {
             this.tableContentWriterStack.getLast().write( unifyEOLs( text ) );
         }
         else
         {
             out.write( unifyEOLs( text ) );
         }
     }
 
     /**
      * Writes a text, appending EOL.
      *
      * @param text The text to write.
      */
     protected void writeln( String text )
     {
         write( text );
         writeEOL();
     }
 
     /**
      * Writes content, escaping special characters.
      *
      * @param text The text to write.
      */
     protected void content( String text )
     {
         write( escaped( text, verbatim ) );
     }
 
     /**
      * Escapes special characters so that the text can be included in a fo file.
      *
      * @param text The text to process.
      * @param verb In verbatim mode, white space and newlines are escaped.
      * @return The text with special characters escaped.
      */
     public static String escaped( String text, boolean verb )
     {
         int length = text.length();
         StringBuilder buffer = new StringBuilder( length );
 
         for ( int i = 0; i < length; ++i )
         {
             char c = text.charAt( i );
             switch ( c )
             {
                 case ' ':
                     if ( verb )
                     {
                         buffer.append( "&#160;" );
                     }
                     else
                     {
                         buffer.append( c );
                     }
                     break;
                 case '<':
                     buffer.append( "&lt;" );
                     break;
                 case '>':
                     buffer.append( "&gt;" );
                     break;
                 case '&':
                     buffer.append( "&amp;" );
                     break;
                 case '\n':
                     buffer.append( EOL );
                     if ( verb )
                     {
                         buffer.append( "<fo:block/>" ).append( EOL );
                     }
                     break;
                 default:
                     if ( needsSymbolFont( c ) )
                     {
                         // TODO: make font configurable?
                         buffer.append( "<fo:inline font-family=\"Symbol\">" ).append( c ).append( "</fo:inline>" );
                     }
                     else
                     {
                         buffer.append( c );
                     }
             }
         }
 
         return buffer.toString();
     }
 
     /** {@inheritDoc} */
     protected void writeStartTag( Tag t, MutableAttributeSet att, boolean isSimpleTag )
     {
         if ( this.tableCaptionXMLWriterStack.isEmpty() )
         {
             super.writeStartTag ( t, att, isSimpleTag );
         }
         else
         {
             String tag = ( getNameSpace() != null ? getNameSpace() + ":" : "" ) + t.toString();
             this.tableCaptionXMLWriterStack.getLast().startElement( tag );
 
             if ( att != null )
             {
                 Enumeration<?> names = att.getAttributeNames();
                 while ( names.hasMoreElements() )
                 {
                     Object key = names.nextElement();
                     Object value = att.getAttribute( key );
 
                     this.tableCaptionXMLWriterStack.getLast().addAttribute( key.toString(), value.toString() );
                 }
             }
 
             if ( isSimpleTag )
             {
                 this.tableCaptionXMLWriterStack.getLast().endElement();
             }
         }
     }
 
     /**
      * {@inheritDoc}
      *
      * @param t a {@link javax.swing.text.html.HTML.Tag} object.
      */
     protected void writeEndTag( Tag t )
     {
         if ( this.tableCaptionXMLWriterStack.isEmpty() )
         {
             super.writeEndTag( t );
         }
         else
         {
             this.tableCaptionXMLWriterStack.getLast().endElement();
         }
     }
 
     private static final char UPPER_ALPHA = 0x391;
     private static final char PIV = 0x3d6;
     private static final char OLINE = 0x203e;
     private static final char DIAMS = 0x2666;
     private static final char EURO = 0x20ac;
     private static final char TRADE = 0x2122;
     private static final char PRIME = 0x2032;
     private static final char PPRIME = 0x2033;
 
     private static boolean needsSymbolFont( char c )
     {
         // greek characters and mathematical symbols, except the euro and trade symbols
         // symbols I couldn't get to display in any font:
         // zwnj (0x200C), zwj (0x200D), lrm (0x200E), rlm (0x200F), oline (0x203E),
         // lceil (0x2038), rceil (0x2039), lfloor (0x203A), rfloor (0x203B)
         return ( c >= UPPER_ALPHA && c <= PIV )
                 || ( c == PRIME || c == PPRIME )
                 || ( c >= OLINE && c <= DIAMS && c != EURO && c != TRADE );
     }
 
     /**
      * Starts a page sequence.
      *
      * @param initPageNumber The initial page number. Should be either "0" (for the first page) or "auto".
      * @param headerText The text to write in the header, if null, nothing is written.
      * @param footerText The text to write in the footer, if null, nothing is written.
      */
     protected void startPageSequence( String initPageNumber, String headerText, String footerText )
     {
         writeln( "<fo:page-sequence initial-page-number=\"" + initPageNumber + "\" master-reference=\"body\">" );
         regionBefore( headerText );
         regionAfter( footerText );
         writeln( "<fo:flow flow-name=\"xsl-region-body\">" );
         chapterHeading( null, true );
     }
 
     /**
      * Writes a 'xsl-region-before' block.
      *
      * @param headerText The text to write in the header, if null, nothing is written.
      */
     protected void regionBefore( String headerText )
     {
         // do nothing, overridden by AggregateSink
     }
 
     /**
      * Writes a 'xsl-region-after' block. By default does nothing, gets overridden by AggregateSink.
      *
      * @param footerText The text to write in the footer, if null, nothing is written.
      */
     protected void regionAfter( String footerText )
     {
         // do nothing, overridden by AggregateSink
     }
 
     /**
      * Writes a chapter heading. By default does nothing, gets overridden by AggregateSink.
      *
      * @param headerText The text to write in the header, if null, the current document title is written.
      * @param chapterNumber True if the chapter number should be written in front of the text.
      */
     protected void chapterHeading( String headerText, boolean chapterNumber )
     {
         // do nothing, overridden by AggregateSink
     }
 
     /**
      * Writes a fo:bookmark-tree. By default does nothing, gets overridden by AggregateSink.
      */
     protected void pdfBookmarks()
     {
         // do nothing, overridden by AggregateSink
     }
 
     /**
      * If debug mode is enabled, log the <code>msg</code> as is, otherwise add unique msg in <code>warnMessages</code>.
      *
      * @param key not null
      * @param msg not null
      * @see #close()
      * @since 1.1.1
      */
     protected void logMessage( String key, String msg )
     {
         msg = "[FO Sink] " + msg;
         if ( getLog().isDebugEnabled() )
         {
             getLog().debug( msg );
 
             return;
         }
 
         if ( warnMessages == null )
         {
             warnMessages = new HashMap<>();
         }
 
         Set<String> set = warnMessages.get( key );
         if ( set == null )
         {
             set = new TreeSet<>();
         }
         set.add( msg );
         warnMessages.put( key, set );
     }
 
     /**
      * {@inheritDoc}
      */
     protected void init()
     {
         super.init();
 
         this.listStack.clear();
         this.tableGridStack.clear();
         this.cellJustifStack.clear();
         this.isCellJustifStack.clear();
         this.cellCountStack.clear();
         this.tableContentWriterStack.clear();
         this.tableCaptionWriterStack.clear();
         this.tableCaptionXMLWriterStack.clear();
         this.tableCaptionStack.clear();
 
         this.section = 0;
         this.subsection = 0;
         this.subsubsection = 0;
         this.verbatim = false;
         this.inFigure = false;
         this.warnMessages = null;
     }
 }