package org.apache.maven.doxia.macro.toc;

 /*

  * 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.StringReader;

 import org.apache.maven.doxia.index.IndexEntry;

 import org.apache.maven.doxia.index.IndexingSink;

 import org.apache.maven.doxia.macro.AbstractMacro;

 import org.apache.maven.doxia.macro.MacroExecutionException;

 import org.apache.maven.doxia.macro.MacroRequest;

 import org.apache.maven.doxia.util.HtmlTools;

 import org.apache.maven.doxia.parser.ParseException;

 import org.apache.maven.doxia.parser.Parser;

 import org.apache.maven.doxia.sink.Sink;

 import org.codehaus.plexus.util.StringUtils;

 /**

  * Macro to display a <code>Table Of Content</code> in a given <code>Sink</code>.

  * The input parameters for this macro are:

  * <dl>

  * <dt>section</dt>

  * <dd>Display a TOC for the specified section only, or all sections if 0.<br/>

  * Positive int, not mandatory, 0 by default.</dd>

  * <dt>fromDepth</dt>

  * <dd>Minimal depth of entries to display in the TOC.

  * Sections are depth 1, sub-sections depth 2, etc.<br/>

  * Positive int, not mandatory, 0 by default.</dd>

  * <dt>toDepth</dt>

  * <dd>Maximum depth of entries to display in the TOC.<br/>

  * Positive int, not mandatory, 5 by default.</dd>

  * </dl>

  * For instance, in an APT file, you could write:

  * <dl>

  * <dt>%{toc|section=2|fromDepth=2|toDepth=3}</dt>

  * <dd>Display a TOC for the second section in the document, including all

  * subsections (depth 2) and  sub-subsections (depth 3).</dd>

  * <dt>%{toc}</dt>

  * <dd>display a TOC with all section and subsections

  * (similar to %{toc|section=0} )</dd>

  * </dl>

  * Moreover, you need to write APT link for section to allow anchor,

  * for instance:

  * <pre>

  * * {SubSection 1}

  * </pre>

  *

  * Similarly, in an XDOC file, you could write:

  * <pre>

  * <macro name="toc">

  *   <param name="section" value="1" />

  *   <param name="fromDepth" value="1" />

  *   <param name="toDepth" value="2" />

  * </macro>

  * </pre>

  *

  * @plexus.component role-hint="toc"

  *

  * @author <a href="mailto:vincent.siveton@gmail.com">Vincent Siveton</a>

  * @version $Id: TocMacro.java 1090706 2011-04-09 23:15:28Z hboutemy $

  */

 public class TocMacro

     extends AbstractMacro

 {

     /** The section to display. */

     private int section;

     /** Start depth. */

     private int fromDepth;

     /** End depth. */

     private int toDepth;

     /** The default end depth. */

     private static final int DEFAULT_DEPTH = 5;

     /** {@inheritDoc} */

     public void execute( Sink sink, MacroRequest request )

         throws MacroExecutionException

     {

         String source = (String) request.getParameter( "sourceContent" );

         Parser parser = (Parser) request.getParameter( "parser" );

         section = getInt( request, "section", 0 );

         fromDepth = getInt( request, "fromDepth", 0 );

         toDepth = getInt( request, "toDepth", DEFAULT_DEPTH );

         if ( fromDepth > toDepth )

         {

             return;

         }

         IndexEntry index = new IndexEntry( "index" );

         IndexingSink tocSink = new IndexingSink( index );

         try

         {

             parser.parse( new StringReader( source ), tocSink );

         }

         catch ( ParseException e )

         {

             throw new MacroExecutionException( "ParseException: " + e.getMessage(), e );

         }

         if ( index.getChildEntries().size() > 0 )

         {

             sink.list( getAttributesFromMap( request.getParameters() ) );

             int i = 1;

             for ( IndexEntry sectionIndex : index.getChildEntries() )

             {

                 if ( ( i == section ) || ( section == 0 ) )

                 {

                     writeSubSectionN( sink, sectionIndex, 1 );

                 }

                 i++;

             }

             sink.list_();

         }

     }

     /**

      * @param sink The sink to write to.

      * @param sectionIndex The section index.

      * @param n The toc depth.

      */

     private void writeSubSectionN( Sink sink, IndexEntry sectionIndex, int n )

     {

         if ( fromDepth <= n )

         {

             sink.listItem();

             sink.link( "#" + HtmlTools.encodeId( sectionIndex.getId() ) );

             sink.text( sectionIndex.getTitle() );

             sink.link_();

         }

         if ( toDepth > n )

         {

             if ( sectionIndex.getChildEntries().size() > 0 )

             {

                 if ( fromDepth <= n )

                 {

                     sink.list();

                 }

                 for ( IndexEntry subsectionIndex : sectionIndex.getChildEntries() )

                 {

                     if ( n == toDepth - 1 )

                     {

                         sink.listItem();

                         sink.link( "#" + HtmlTools.encodeId( subsectionIndex.getId() ) );

                         sink.text( subsectionIndex.getTitle() );

                         sink.link_();

                         sink.listItem_();

                     }

                     else

                     {

                         writeSubSectionN( sink, subsectionIndex, n + 1 );

                     }

                 }

                 if ( fromDepth <= n )

                 {

                     sink.list_();

                 }

             }

         }

         if ( fromDepth <= n )

         {

             sink.listItem_();

         }

     }

     /**

      * @param request The MacroRequest.

      * @param parameter The parameter.

      * @param defaultValue the default value.

      * @return the int value of a parameter in the request.

      * @throws MacroExecutionException if something goes wrong.

      */

     private static int getInt( MacroRequest request, String parameter, int defaultValue )

         throws MacroExecutionException

     {

         String value = (String) request.getParameter( parameter );

         if ( StringUtils.isEmpty( value ) )

         {

             return defaultValue;

         }

         int i;

         try

         {

             i = Integer.parseInt( value );

         }

         catch ( NumberFormatException e )

         {

             return defaultValue;

         }

         if ( i < 0 )

         {

             throw new MacroExecutionException( "The " + parameter + "=" + i + " should be positive." );

         }

         return i;

     }

 }