package org.apache.maven.doxia.plugin;
   
   import java.util.ArrayList;
   import java.util.Iterator;
   import java.util.List;
   
   import org.apache.maven.plugin.AbstractMojo;
   import org.apache.maven.plugin.MojoExecutionException;
   
  /**
   * Display help information on doxia-maven-plugin.<br/> Call <pre>  mvn doxia:help -Ddetail=true -Dgoal=&lt;goal-name&gt;</pre> to display parameter details.
   *
   * @version generated on Wed Apr 27 01:35:44 CEST 2011
   * @author org.apache.maven.tools.plugin.generator.PluginHelpGenerator (version 2.5.1)
   * @goal help
   * @requiresProject false
   */
  public class HelpMojo
      extends AbstractMojo
  {
      /**
       * If <code>true</code>, display all settable properties for each goal.
       * 
       * @parameter expression="${detail}" default-value="false"
       */
      private boolean detail;
  
      /**
       * The name of the goal for which to show help. If unspecified, all goals will be displayed.
       * 
       * @parameter expression="${goal}"
       */
      private java.lang.String goal;
  
      /**
       * The maximum length of a display line, should be positive.
       * 
       * @parameter expression="${lineLength}" default-value="80"
       */
      private int lineLength;
  
      /**
       * The number of spaces per indentation level, should be positive.
       * 
       * @parameter expression="${indentSize}" default-value="2"
       */
      private int indentSize;
  
  
      /** {@inheritDoc} */
      public void execute()
          throws MojoExecutionException
      {
          if ( lineLength <= 0 )
          {
              getLog().warn( "The parameter 'lineLength' should be positive, using '80' as default." );
              lineLength = 80;
          }
          if ( indentSize <= 0 )
          {
              getLog().warn( "The parameter 'indentSize' should be positive, using '2' as default." );
              indentSize = 2;
          }
  
          StringBuffer sb = new StringBuffer();
  
          append( sb, "org.apache.maven.doxia:doxia-maven-plugin:1.2", 0 );
          append( sb, "", 0 );
  
          append( sb, "Doxia :: Maven Plugin", 0 );
          append( sb, "A Maven plugin for Doxia.", 1 );
          append( sb, "", 0 );
  
          if ( goal == null || goal.length() <= 0 )
          {
              append( sb, "This plugin has 2 goals:", 0 );
              append( sb, "", 0 );
          }
  
          if ( goal == null || goal.length() <= 0 || "help".equals( goal ) )
          {
              append( sb, "doxia:help", 0 );
              append( sb, "Display help information on doxia-maven-plugin.\nCall\n\u00a0\u00a0mvn\u00a0doxia:help\u00a0-Ddetail=true\u00a0-Dgoal=<goal-name>\nto display parameter details.", 1 );
              append( sb, "", 0 );
              if ( detail )
              {
                  append( sb, "Available parameters:", 1 );
                  append( sb, "", 0 );
  
                  append( sb, "detail (Default: false)", 2 );
                  append( sb, "If true, display all settable properties for each goal.", 3 );
                  append( sb, "", 0 );
  
                  append( sb, "goal", 2 );
                  append( sb, "The name of the goal for which to show help. If unspecified, all goals will be displayed.", 3 );
                  append( sb, "", 0 );
  
                  append( sb, "indentSize (Default: 2)", 2 );
                  append( sb, "The number of spaces per indentation level, should be positive.", 3 );
                 append( sb, "", 0 );
 
                 append( sb, "lineLength (Default: 80)", 2 );
                 append( sb, "The maximum length of a display line, should be positive.", 3 );
                 append( sb, "", 0 );
             }
         }
 
         if ( goal == null || goal.length() <= 0 || "render-books".equals( goal ) )
         {
             append( sb, "doxia:render-books", 0 );
             append( sb, "A Mojo to create books in different output formats.", 1 );
             append( sb, "", 0 );
             if ( detail )
             {
                 append( sb, "Available parameters:", 1 );
                 append( sb, "", 0 );
 
                 append( sb, "basedir (Default: ${basedir})", 2 );
                 append( sb, "Base directory of the project.", 3 );
                 append( sb, "", 0 );
 
                 append( sb, "books", 2 );
                 append( sb, "A list of books.", 3 );
                 append( sb, "", 0 );
 
                 append( sb, "generatedDocs (Default: ${project.build.directory}/generated-site)", 2 );
                 append( sb, "Directory containing the generated project docs.", 3 );
                 append( sb, "", 0 );
 
                 append( sb, "inputEncoding (Default: ${project.build.sourceEncoding})", 2 );
                 append( sb, "Specifies the input encoding.", 3 );
                 append( sb, "", 0 );
 
                 append( sb, "locales (Default: ${locales})", 2 );
                 append( sb, "A comma separated list of locales supported by Maven. The first valid token will be the default Locale for this instance of the Java Virtual Machine.", 3 );
                 append( sb, "", 0 );
 
                 append( sb, "outputEncoding (Default: ${project.reporting.outputEncoding})", 2 );
                 append( sb, "Specifies the output encoding.", 3 );
                 append( sb, "", 0 );
             }
         }
 
         if ( getLog().isInfoEnabled() )
         {
             getLog().info( sb.toString() );
         }
     }
 
     /**
      * <p>Repeat a String <code>n</code> times to form a new string.</p>
      *
      * @param str String to repeat
      * @param repeat number of times to repeat str
      * @return String with repeated String
      * @throws NegativeArraySizeException if <code>repeat < 0</code>
      * @throws NullPointerException if str is <code>null</code>
      */
     private static String repeat( String str, int repeat )
     {
         StringBuffer buffer = new StringBuffer( repeat * str.length() );
 
         for ( int i = 0; i < repeat; i++ )
         {
             buffer.append( str );
         }
 
         return buffer.toString();
     }
 
     /** 
      * Append a description to the buffer by respecting the indentSize and lineLength parameters.
      * <b>Note</b>: The last character is always a new line.
      * 
      * @param sb The buffer to append the description, not <code>null</code>.
      * @param description The description, not <code>null</code>.
      * @param indent The base indentation level of each line, must not be negative.
      */
     private void append( StringBuffer sb, String description, int indent )
     {
         for ( Iterator it = toLines( description, indent, indentSize, lineLength ).iterator(); it.hasNext(); )
         {
             sb.append( it.next().toString() ).append( '\n' );
         }
     }
 
     /** 
      * Splits the specified text into lines of convenient display length.
      * 
      * @param text The text to split into lines, must not be <code>null</code>.
      * @param indent The base indentation level of each line, must not be negative.
      * @param indentSize The size of each indentation, must not be negative.
      * @param lineLength The length of the line, must not be negative.
      * @return The sequence of display lines, never <code>null</code>.
      * @throws NegativeArraySizeException if <code>indent < 0</code>
      */
     private static List toLines( String text, int indent, int indentSize, int lineLength )
     {
         List lines = new ArrayList();
 
         String ind = repeat( "\t", indent );
         String[] plainLines = text.split( "(\r\n)|(\r)|(\n)" );
         for ( int i = 0; i < plainLines.length; i++ )
         {
             toLines( lines, ind + plainLines[i], indentSize, lineLength );
         }
 
         return lines;
     }
 
     /** 
      * Adds the specified line to the output sequence, performing line wrapping if necessary.
      * 
      * @param lines The sequence of display lines, must not be <code>null</code>.
      * @param line The line to add, must not be <code>null</code>.
      * @param indentSize The size of each indentation, must not be negative.
      * @param lineLength The length of the line, must not be negative.
      */
     private static void toLines( List lines, String line, int indentSize, int lineLength )
     {
         int lineIndent = getIndentLevel( line );
         StringBuffer buf = new StringBuffer( 256 );
         String[] tokens = line.split( " +" );
         for ( int i = 0; i < tokens.length; i++ )
         {
             String token = tokens[i];
             if ( i > 0 )
             {
                 if ( buf.length() + token.length() >= lineLength )
                 {
                     lines.add( buf.toString() );
                     buf.setLength( 0 );
                     buf.append( repeat( " ", lineIndent * indentSize ) );
                 }
                 else
                 {
                     buf.append( ' ' );
                 }
             }
             for ( int j = 0; j < token.length(); j++ )
             {
                 char c = token.charAt( j );
                 if ( c == '\t' )
                 {
                     buf.append( repeat( " ", indentSize - buf.length() % indentSize ) );
                 }
                 else if ( c == '\u00A0' )
                 {
                     buf.append( ' ' );
                 }
                 else
                 {
                     buf.append( c );
                 }
             }
         }
         lines.add( buf.toString() );
     }
 
     /** 
      * Gets the indentation level of the specified line.
      * 
      * @param line The line whose indentation level should be retrieved, must not be <code>null</code>.
      * @return The indentation level of the line.
      */
     private static int getIndentLevel( String line )
     {
         int level = 0;
         for ( int i = 0; i < line.length() && line.charAt( i ) == '\t'; i++ )
         {
             level++;
         }
         for ( int i = level + 1; i <= level + 4 && i < line.length(); i++ )
         {
             if ( line.charAt( i ) == '\t' )
             {
                 level++;
                 break;
             }
         }
         return level;
     }
 }