package org.apache.maven.doxia.module.apt;
   
   /*
    * 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.PrintWriter;
  import java.io.Writer;
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Stack;
  
  import org.apache.maven.doxia.sink.SinkEventAttributes;
  import org.apache.maven.doxia.sink.impl.AbstractTextSink;
  import org.apache.maven.doxia.sink.impl.SinkEventAttributeSet;
  import org.codehaus.plexus.util.StringUtils;
  
  /**
   * APT generator implementation.
   * <br>
   * <b>Note</b>: The encoding used is UTF-8.
   *
   * @author eredmond
   * @since 1.0
   */
  public class AptSink
      extends AbstractTextSink
      implements AptMarkup
  {
      // ----------------------------------------------------------------------
      // Instance fields
      // ----------------------------------------------------------------------
  
      /**  A buffer that holds the current text when headerFlag or bufferFlag set to <code>true</code>. */
      private StringBuffer buffer;
  
      /**  A buffer that holds the table caption. */
      private StringBuilder tableCaptionBuffer;
  
      /**  author. */
      private String author;
  
      /**  title. */
      private String title;
  
      /**  date. */
      private String date;
  
      /** startFlag. */
      private boolean startFlag;
  
      /**  tableCaptionFlag. */
      private boolean tableCaptionFlag;
  
      /**  tableCellFlag. */
      private boolean tableCellFlag;
  
      /**  headerFlag. */
      private boolean headerFlag;
  
      /**  bufferFlag. */
      private boolean bufferFlag;
  
      /**  itemFlag. */
      private boolean itemFlag;
  
      /**  verbatimFlag. */
      private boolean verbatimFlag;
  
      /**  boxed verbatim. */
      private boolean isBoxed;
  
      /**  gridFlag for tables. */
      private boolean gridFlag;
  
      /**  number of cells in a table. */
      private int cellCount;
  
      /**  The writer to use. */
      private final PrintWriter writer;
  
      /**  justification of table cells. */
      private int[] cellJustif;
  
     /**  a line of a row in a table. */
     private String rowLine;
 
     /**  listNestingIndent. */
     private String listNestingIndent;
 
     /**  listStyles. */
     private final Stack<String> listStyles;
 
     /** Keep track of the closing tags for inline events. */
     protected Stack<List<String>> inlineStack = new Stack<>();
 
     // ----------------------------------------------------------------------
     // Public protected methods
     // ----------------------------------------------------------------------
 
     /**
      * Constructor, initialize the Writer and the variables.
      *
      * @param writer not null writer to write the result. <b>Should</b> be an UTF-8 Writer.
      * You could use <code>newWriter</code> methods from {@link org.codehaus.plexus.util.WriterFactory}.
      */
     protected AptSink( Writer writer )
     {
         this.writer = new PrintWriter( writer );
         this.listStyles = new Stack<>();
 
         init();
     }
 
     /**
      * Returns the buffer that holds the current text.
      *
      * @return A StringBuffer.
      */
     protected StringBuffer getBuffer()
     {
         return buffer;
     }
 
     /**
      * Used to determine whether we are in head mode.
      *
      * @param headFlag True for head mode.
      */
     protected void setHeadFlag( boolean headFlag )
     {
         this.headerFlag = headFlag;
     }
 
     /**
      * Reset all variables.
      *
      * @deprecated since 1.1.2, use {@link #init()} instead of.
      */
     protected void resetState()
     {
         init();
     }
 
     /**
      * {@inheritDoc}
      */
     protected void init()
     {
         super.init();
 
         resetBuffer();
 
         this.tableCaptionBuffer = new StringBuilder();
         this.listNestingIndent = "";
 
         this.author = null;
         this.title = null;
         this.date = null;
         this.startFlag = true;
         this.tableCaptionFlag = false;
         this.tableCellFlag = false;
         this.headerFlag = false;
         this.bufferFlag = false;
         this.itemFlag = false;
         this.verbatimFlag = false;
         this.isBoxed = false;
         this.gridFlag = false;
         this.cellCount = 0;
         this.cellJustif = null;
         this.rowLine = null;
         this.listStyles.clear();
         this.inlineStack.clear();
     }
 
     /**
      * Reset the StringBuilder.
      */
     protected void resetBuffer()
     {
         buffer = new StringBuffer();
     }
 
     /**
      * Reset the TableCaptionBuffer.
      */
     protected void resetTableCaptionBuffer()
     {
         tableCaptionBuffer = new StringBuilder();
     }
 
     /**
      * {@inheritDoc}
      */
     public void head()
     {
         boolean startFlag = this.startFlag;
 
         init();
 
         headerFlag = true;
         this.startFlag = startFlag;
     }
 
     /**
      * {@inheritDoc}
      */
     public void head_()
     {
         headerFlag = false;
 
         if ( ! startFlag )
         {
             write( EOL );
         }
         write( HEADER_START_MARKUP + EOL );
         if ( title != null )
         {
             write( " " + title + EOL );
         }
         write( HEADER_START_MARKUP + EOL );
         if ( author != null )
         {
             write( " " + author + EOL );
         }
         write( HEADER_START_MARKUP + EOL );
         if ( date != null )
         {
             write( " " + date + EOL );
         }
         write( HEADER_START_MARKUP + EOL );
     }
 
     /**
      * {@inheritDoc}
      */
     public void title_()
     {
         if ( buffer.length() > 0 )
         {
             title = buffer.toString();
             resetBuffer();
         }
     }
 
     /**
      * {@inheritDoc}
      */
     public void author_()
     {
         if ( buffer.length() > 0 )
         {
             author = buffer.toString();
             resetBuffer();
         }
     }
 
     /**
      * {@inheritDoc}
      */
     public void date_()
     {
         if ( buffer.length() > 0 )
         {
             date = buffer.toString();
             resetBuffer();
         }
     }
 
     /**
      * {@inheritDoc}
      */
     public void section1_()
     {
         write( EOL );
     }
 
     /**
      * {@inheritDoc}
      */
     public void section2_()
     {
         write( EOL );
     }
 
     /**
      * {@inheritDoc}
      */
     public void section3_()
     {
         write( EOL );
     }
 
     /**
      * {@inheritDoc}
      */
     public void section4_()
     {
         write( EOL );
     }
 
     /**
      * {@inheritDoc}
      */
     public void section5_()
     {
         write( EOL );
     }
 
     /**
      * {@inheritDoc}
      */
     public void sectionTitle1()
     {
         write( EOL );
     }
 
     /**
      * {@inheritDoc}
      */
     public void sectionTitle1_()
     {
         write( EOL + EOL );
     }
 
     /**
      * {@inheritDoc}
      */
     public void sectionTitle2()
     {
         write( EOL + SECTION_TITLE_START_MARKUP );
     }
 
     /**
      * {@inheritDoc}
      */
     public void sectionTitle2_()
     {
         write( EOL + EOL );
     }
 
     /**
      * {@inheritDoc}
      */
     public void sectionTitle3()
     {
         write( EOL + StringUtils.repeat( SECTION_TITLE_START_MARKUP, 2 ) );
     }
 
     /**
      * {@inheritDoc}
      */
     public void sectionTitle3_()
     {
         write( EOL + EOL );
     }
 
     /**
      * {@inheritDoc}
      */
     public void sectionTitle4()
     {
         write( EOL + StringUtils.repeat( SECTION_TITLE_START_MARKUP, 3 ) );
     }
 
     /**
      * {@inheritDoc}
      */
     public void sectionTitle4_()
     {
         write( EOL + EOL );
     }
 
     /**
      * {@inheritDoc}
      */
     public void sectionTitle5()
     {
         write( EOL + StringUtils.repeat( SECTION_TITLE_START_MARKUP, 4 ) );
     }
 
     /**
      * {@inheritDoc}
      */
     public void sectionTitle5_()
     {
         write( EOL + EOL );
     }
 
     /**
      * {@inheritDoc}
      */
     public void list()
     {
         listNestingIndent += " ";
         listStyles.push( LIST_START_MARKUP );
         write( EOL );
     }
 
     /**
      * {@inheritDoc}
      */
     public void list_()
     {
         if ( listNestingIndent.length() <= 1 )
         {
             write( EOL + listNestingIndent + LIST_END_MARKUP + EOL );
         }
         else
         {
             write( EOL );
         }
         listNestingIndent = StringUtils.chomp( listNestingIndent, " " );
         listStyles.pop();
         itemFlag = false;
     }
 
     /**
      * {@inheritDoc}
      */
     public void listItem()
     {
         //if ( !numberedList )
         //write( EOL + listNestingIndent + "*" );
         //else
         numberedListItem();
         itemFlag = true;
     }
 
     /**
      * {@inheritDoc}
      */
     public void listItem_()
     {
         write( EOL );
         itemFlag = false;
     }
 
     /** {@inheritDoc} */
     public void numberedList( int numbering )
     {
         listNestingIndent += " ";
         write( EOL );
 
         String style;
         switch ( numbering )
         {
             case NUMBERING_UPPER_ALPHA:
                 style = String.valueOf( NUMBERING_UPPER_ALPHA_CHAR );
                 break;
             case NUMBERING_LOWER_ALPHA:
                 style = String.valueOf( NUMBERING_LOWER_ALPHA_CHAR );
                 break;
             case NUMBERING_UPPER_ROMAN:
                 style = String.valueOf( NUMBERING_UPPER_ROMAN_CHAR );
                 break;
             case NUMBERING_LOWER_ROMAN:
                 style = String.valueOf( NUMBERING_LOWER_ROMAN_CHAR );
                 break;
             case NUMBERING_DECIMAL:
             default:
                 style = String.valueOf( NUMBERING );
         }
 
         listStyles.push( style );
     }
 
     /**
      * {@inheritDoc}
      */
     public void numberedList_()
     {
         if ( listNestingIndent.length() <= 1 )
         {
             write( EOL + listNestingIndent + LIST_END_MARKUP + EOL );
         }
         else
         {
             write( EOL );
         }
         listNestingIndent = StringUtils.chomp( listNestingIndent, " " );
         listStyles.pop();
         itemFlag = false;
     }
 
     /**
      * {@inheritDoc}
      */
     public void numberedListItem()
     {
         String style = listStyles.peek();
         if ( style.equals( String.valueOf( STAR ) ) )
         {
             write( EOL + listNestingIndent + STAR + SPACE );
         }
         else
         {
             write( EOL + listNestingIndent + LEFT_SQUARE_BRACKET
                 + LEFT_SQUARE_BRACKET + style + RIGHT_SQUARE_BRACKET
                 + RIGHT_SQUARE_BRACKET + SPACE );
         }
         itemFlag = true;
     }
 
     /**
      * {@inheritDoc}
      */
     public void numberedListItem_()
     {
         write( EOL );
         itemFlag = false;
     }
 
     /**
      * {@inheritDoc}
      */
     public void definitionList()
     {
         listNestingIndent += " ";
         listStyles.push( "" );
         write( EOL );
     }
 
     /**
      * {@inheritDoc}
      */
     public void definitionList_()
     {
         if ( listNestingIndent.length() <= 1 )
         {
             write( EOL + listNestingIndent + LIST_END_MARKUP + EOL );
         }
         else
         {
             write( EOL );
         }
         listNestingIndent = StringUtils.chomp( listNestingIndent, " " );
         listStyles.pop();
         itemFlag = false;
     }
 
     /**
      * {@inheritDoc}
      */
     public void definedTerm()
     {
         write( EOL + " [" );
     }
 
     /**
      * {@inheritDoc}
      */
     public void definedTerm_()
     {
         write( "] " );
     }
 
     /**
      * {@inheritDoc}
      */
     public void definition()
     {
         itemFlag = true;
     }
 
     /**
      * {@inheritDoc}
      */
     public void definition_()
     {
         write( EOL );
         itemFlag = false;
     }
 
     /**
      * {@inheritDoc}
      */
     public void pageBreak()
     {
         write( EOL + PAGE_BREAK + EOL );
     }
 
     /**
      * {@inheritDoc}
      */
     public void paragraph()
     {
         if ( tableCellFlag )
         {
             // ignore paragraphs in table cells
         }
         else if ( itemFlag )
         {
             write( EOL + EOL + "  " + listNestingIndent );
         }
         else
         {
             write( EOL + " " );
         }
     }
 
     /**
      * {@inheritDoc}
      */
     public void paragraph_()
     {
         if ( tableCellFlag )
         {
             // ignore paragraphs in table cells
         }
         else
         {
             write( EOL + EOL );
         }
     }
 
     /** {@inheritDoc} */
     public void verbatim( boolean boxed )
     {
         verbatimFlag = true;
         this.isBoxed = boxed;
         write( EOL );
         if ( boxed )
         {
             write( EOL + BOXED_VERBATIM_START_MARKUP + EOL );
         }
         else
         {
             write( EOL + NON_BOXED_VERBATIM_START_MARKUP + EOL );
         }
     }
 
     /**
      * {@inheritDoc}
      */
     public void verbatim_()
     {
         if ( isBoxed )
         {
             write( EOL + BOXED_VERBATIM_END_MARKUP + EOL );
         }
         else
         {
             write( EOL + NON_BOXED_VERBATIM_END_MARKUP + EOL );
         }
         isBoxed = false;
         verbatimFlag = false;
     }
 
     /**
      * {@inheritDoc}
      */
     public void horizontalRule()
     {
         write( EOL + HORIZONTAL_RULE_MARKUP + EOL );
     }
 
     /**
      * {@inheritDoc}
      */
     public void table()
     {
         write( EOL );
     }
 
     /**
      * {@inheritDoc}
      */
     public void table_()
     {
         if ( rowLine != null )
         {
             write( rowLine );
         }
         rowLine = null;
 
         if ( tableCaptionBuffer.length() > 0 )
         {
             text( tableCaptionBuffer.toString() + EOL );
         }
 
         resetTableCaptionBuffer();
     }
 
     /** {@inheritDoc} */
     public void tableRows( int[] justification, boolean grid )
     {
         cellJustif = justification;
         gridFlag = grid;
     }
 
     /**
      * {@inheritDoc}
      */
     public void tableRows_()
     {
         cellJustif = null;
         gridFlag = false;
     }
 
     /**
      * {@inheritDoc}
      */
     public void tableRow()
     {
         bufferFlag = true;
         cellCount = 0;
     }
 
     /**
      * {@inheritDoc}
      */
     public void tableRow_()
     {
         bufferFlag = false;
 
         // write out the header row first, then the data in the buffer
         buildRowLine();
 
         write( rowLine );
 
         // TODO: This will need to be more clever, for multi-line cells
         if ( gridFlag )
         {
             write( TABLE_ROW_SEPARATOR_MARKUP );
         }
 
         write( buffer.toString() );
 
         resetBuffer();
 
         write( EOL );
 
         // only reset cell count if this is the last row
         cellCount = 0;
     }
 
     /** Construct a table row. */
     private void buildRowLine()
     {
         StringBuilder rLine = new StringBuilder();
         rLine.append( TABLE_ROW_START_MARKUP );
 
         for ( int i = 0; i < cellCount; i++ )
         {
             if ( cellJustif != null )
             {
                 switch ( cellJustif[i] )
                 {
                 case 1:
                     rLine.append( TABLE_COL_LEFT_ALIGNED_MARKUP );
                     break;
                 case 2:
                     rLine.append( TABLE_COL_RIGHT_ALIGNED_MARKUP );
                     break;
                 default:
                     rLine.append( TABLE_COL_CENTERED_ALIGNED_MARKUP );
                 }
             }
             else
             {
                 rLine.append( TABLE_COL_CENTERED_ALIGNED_MARKUP );
             }
         }
         rLine.append( EOL );
 
         this.rowLine = rLine.toString();
     }
 
     /**
      * {@inheritDoc}
      */
     public void tableCell()
     {
         tableCell( false );
     }
 
     /**
      * {@inheritDoc}
      */
     public void tableHeaderCell()
     {
         tableCell( true );
     }
 
     /**
      * Starts a table cell.
      *
      * @param headerRow If this cell is part of a header row.
      */
     public void tableCell( boolean headerRow )
     {
         if ( headerRow )
         {
             buffer.append( TABLE_CELL_SEPARATOR_MARKUP );
         }
         tableCellFlag = true;
     }
 
     /**
      * {@inheritDoc}
      */
     public void tableCell_()
     {
         endTableCell();
     }
 
     /**
      * {@inheritDoc}
      */
     public void tableHeaderCell_()
     {
         endTableCell();
     }
 
     /**
      * Ends a table cell.
      */
     private void endTableCell()
     {
         tableCellFlag = false;
         buffer.append( TABLE_CELL_SEPARATOR_MARKUP );
         cellCount++;
     }
 
     /**
      * {@inheritDoc}
      */
     public void tableCaption()
     {
         tableCaptionFlag = true;
     }
 
     /**
      * {@inheritDoc}
      */
     public void tableCaption_()
     {
         tableCaptionFlag = false;
     }
 
     /**
      * {@inheritDoc}
      */
     public void figureCaption_()
     {
         write( EOL );
     }
 
     /** {@inheritDoc} */
     public void figureGraphics( String name )
     {
         write( EOL + "[" + name + "] " );
     }
 
     /** {@inheritDoc} */
     public void anchor( String name )
     {
         write( ANCHOR_START_MARKUP );
     }
 
     /**
      * {@inheritDoc}
      */
     public void anchor_()
     {
         write( ANCHOR_END_MARKUP );
     }
 
     /** {@inheritDoc} */
     public void link( String name )
     {
         if ( !headerFlag )
         {
             write( LINK_START_1_MARKUP );
             text( name.startsWith( "#" ) ? name.substring( 1 ) : name );
             write( LINK_START_2_MARKUP );
         }
     }
 
     /**
      * {@inheritDoc}
      */
     public void link_()
     {
         if ( !headerFlag )
         {
             write( LINK_END_MARKUP );
         }
     }
 
     /**
      * A link with a target.
      *
      * @param name The name of the link.
      * @param target The link target.
      */
     public void link( String name, String target )
     {
         if ( !headerFlag )
         {
             write( LINK_START_1_MARKUP );
             text( target );
             write( LINK_START_2_MARKUP );
             text( name );
         }
     }
 
     /**
      * {@inheritDoc}
      */
     public void inline()
     {
         inline( null );
     }
 
     /** {@inheritDoc} */
     public void inline( SinkEventAttributes attributes )
     {
         if ( !headerFlag )
         {
             List<String> tags = new ArrayList<>();
 
             if ( attributes != null )
             {
 
                 if ( attributes.containsAttribute( SinkEventAttributes.SEMANTICS, "italic" ) )
                 {
                     write( ITALIC_START_MARKUP );
                     tags.add( 0, ITALIC_END_MARKUP );
                 }
 
                 if ( attributes.containsAttribute( SinkEventAttributes.SEMANTICS, "bold" ) )
                 {
                     write( BOLD_START_MARKUP );
                     tags.add( 0, BOLD_END_MARKUP );
                 }
 
                 if ( attributes.containsAttribute( SinkEventAttributes.SEMANTICS, "code" ) )
                 {
                     write( MONOSPACED_START_MARKUP );
                     tags.add( 0, MONOSPACED_END_MARKUP );
                 }
 
             }
 
             inlineStack.push( tags );
         }
     }
 
     /**
      * {@inheritDoc}
      */
     public void inline_()
     {
         if ( !headerFlag )
         {
             for ( String tag: inlineStack.pop() )
             {
                 write( 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()
     {
         if ( headerFlag || bufferFlag )
         {
             buffer.append( EOL );
         }
         else if ( verbatimFlag )
         {
             write( EOL );
         }
         else
         {
             write( "\\" + EOL );
         }
     }
 
     /**
      * {@inheritDoc}
      */
     public void nonBreakingSpace()
     {
         if ( headerFlag || bufferFlag )
         {
             buffer.append( NON_BREAKING_SPACE_MARKUP );
         }
         else
         {
             write( NON_BREAKING_SPACE_MARKUP );
         }
     }
 
     /** {@inheritDoc} */
     public void text( String text )
     {
         if ( tableCaptionFlag )
         {
             tableCaptionBuffer.append( text );
         }
         else if ( headerFlag || bufferFlag )
         {
             buffer.append( text );
         }
         else if ( verbatimFlag )
         {
             verbatimContent( text );
         }
         else
         {
             content( text );
         }
     }
 
     /** {@inheritDoc} */
     public void rawText( String text )
     {
         write( text );
     }
 
     /** {@inheritDoc} */
     public void comment( String comment )
     {
         rawText( ( startFlag ? "" : EOL ) + COMMENT + COMMENT + comment );
     }
 
     /**
      * {@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 )
     {
         getLog().warn( "[Apt Sink] Unknown Sink event: '" + name + "', ignoring!" );
     }
 
     /**
      * Write text to output.
      *
      * @param text The text to write.
      */
     protected void write( String text )
     {
         startFlag = false;
         if ( tableCellFlag )
         {
             buffer.append( text );
         }
         else
         {
             writer.write( unifyEOLs( text ) );
         }
     }
 
     /**
      * Write Apt escaped text to output.
      *
      * @param text The text to write.
      */
     protected void content( String text )
     {
         write( escapeAPT( text ) );
     }
 
     /**
      * Write Apt escaped text to output.
      *
      * @param text The text to write.
      */
     protected void verbatimContent( String text )
     {
         write( escapeAPT( text ) );
     }
 
     /**
      * {@inheritDoc}
      */
     public void flush()
     {
         writer.flush();
     }
 
     /**
      * {@inheritDoc}
      */
     public void close()
     {
         writer.close();
 
         init();
     }
 
     // ----------------------------------------------------------------------
     // Private methods
     // ----------------------------------------------------------------------
 
     /**
      * Escape special characters in a text in APT:
      *
      * <pre>
      * \~, \=, \-, \+, \*, \[, \], \<, \>, \{, \}, \\
      * </pre>
      *
      * @param text the String to escape, may be null
      * @return the text escaped, "" if null String input
      */
     private static String escapeAPT( String text )
     {
         if ( text == null )
         {
             return "";
         }
 
         int length = text.length();
         StringBuilder buffer = new StringBuilder( length );
 
         for ( int i = 0; i < length; ++i )
         {
             char c = text.charAt( i );
             switch ( c )
             { // 0080
                 case '\\':
                 case '~':
                 case '=':
                 case '-':
                 case '+':
                 case '*':
                 case '[':
                 case ']':
                 case '<':
                 case '>':
                 case '{':
                 case '}':
                     buffer.append( '\\' );
                     buffer.append( c );
                     break;
                 default:
                     buffer.append( c );
             }
         }
 
         return buffer.toString();
     }
 }