code: /**
   * Copyright (c) 2004-2005, Regents of the University of California
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * Redistributions of source code must retain the above copyright notice,
   * this list of conditions and the following disclaimer.
   *
   * Redistributions in binary form must reproduce the above copyright
   * notice, this list of conditions and the following disclaimer in the
   * documentation and/or other materials provided with the distribution.
   *
   * Neither the name of the University of California, Los Angeles nor the
   * names of its contributors may be used to endorse or promote products
   * derived from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
   * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  package cck.help;
  
  import cck.text.StringUtil;
  import cck.text.Terminal;
  import cck.util.ClassMap;
  
  /**
   * The <code>ClassMapValueItem</code> is a help item representing one possible value
   * for an option, where the value of the option is used to access a class map. For
   * example, the "-action" option accepts a value where the user specifies what
   * action the main program should perform. In this case, for each of the possible
   * values of this option, a <code>ClassMapValueItem</code> instance will be created
   * that is used in constructing the help text for the actions help category.
   *
   * @author Ben L. Titzer
   */
  public class ClassMapValueItem implements HelpItem {
  
      public final int indent;
      public final String optname;
      public final String optvalue;
      public final ClassMap map;
      boolean isHelpCategory;
      protected String help;
  
      /**
       * The constructor for the <code>ClassMapValueItem</code> class creates a new instance of
       * a help item for the specified option and value. The classmap passed is used to
       * get an instance of the object corresponding to that value so that any help that it has
       * can be added underneath the option.
       *
       * @param indent   the number of spaces to indent when printing the help
       * @param optname  the name of the option
       * @param optvalue the string value of the option
       * @param map      the classmap which is used to get instances for this value
       */
      public ClassMapValueItem(int indent, String optname, String optvalue, ClassMap map) {
          this.optname = optname;
          this.optvalue = optvalue;
          this.map = map;
          this.indent = indent;
      }
  
      /**
       * The <code>getHelp()</code> method returns a help string for this help item.
       *
       * @return a string representing the help for this item
       */
      public String getHelp() {
          if (help != null) return help;
          else return computeHelp();
      }
  
      /**
       * The <code>printHelp()</code> method prints out a well-formatted paragraph for this option
       * and the value specified. If there is help for the value associated with this option, it
       * will format it as part of the help for this item.
       */
      public void printHelp() {
          String h = getHelp();
          Terminal.print(StringUtil.space(indent));
          String name;
          if (isHelpCategory && Terminal.htmlColors) {
              name = "<a href=" + optvalue + ".html>" + optvalue + "</a>";
          } else {
              name = optvalue;
          }
          Terminal.printPair(Terminal.COLOR_GREEN, Terminal.COLOR_YELLOW, optname, "=", name);
          Terminal.nextln();
          Terminal.println(StringUtil.formatParagraphs(h, indent + 4, 0, Terminal.MAXLINE));
      }
  
      /**
       * The <code>computeHelp()</code> method looks up this value in the specified class map,
       * and if the object is a help item itself, will return its help. If it is not a help item,
       * then it will return a default string.
       *
       * @return help for this item
       */
      private String computeHelp() {
          try {
              HelpItem item = (HelpItem) map.getObjectOfClass(optvalue);
              help = item.getHelp();
              if (item instanceof HelpCategory) isHelpCategory = true;
          } catch (Throwable t) {
              return "(No help available for this item.)";
          }
          return help;
      }
  }
  