/*

  * Copyright (C) 1998-2001 Semiotek Inc.  All Rights Reserved.

  *

  * Redistribution and use in source and binary forms, with or without

  * modification, are permitted under the terms of either of the following

  * Open Source licenses:

  *

  * The GNU General Public License, version 2, or any later version, as

  * published by the Free Software Foundation

  * (http://www.fsf.org/copyleft/gpl.html);

  *

  *  or

  *

  * The Semiotek Public License (http://webmacro.org/LICENSE.)

  *

  * This software is provided "as is", with NO WARRANTY, not even the

  * implied warranties of fitness to purpose, or merchantability. You

  * assume all risks and liabilities associated with its use.

  *

  * See www.webmacro.org for more information on the WebMacro project.

  */

 package org.webmacro.engine;

 /**

  * MacroDefinition.java

  *

  * Represents a (C-style) macro, which gets expanded during the

  * building of a template.  Not to be confused with Macro as used

  * by WebMacro, which is something else.

  * @author Brian Goetz

  */

 public class MacroDefinition

 {

     private String name;

     private String[] argNames;

     Object macroBody;

     public MacroDefinition (String name,

                             String[] argNames,

                             Object macroBody)

     {

         this.name = name;

         this.argNames = argNames;

         this.macroBody = macroBody;

     }

     public String[] getArgNames ()

     {

         return argNames;

     }

     public String getName ()

     {

         return name;

     }

     public Object getMacroBody ()

     {

         return macroBody;

     }

     public Object expand (Object[] args, BuildContext bc)

             throws BuildException

     {

         if (args.length != argNames.length)

             throw new BuildException("#" + name + ": invoked with "

                     + args.length + " arguments, expecting "

                     + argNames.length + " arguments");

         if (macroBody instanceof Builder)

         {

             if (bc instanceof MacroBuildContext)

                 bc = ((MacroBuildContext) bc).getRootContext();

             MacroBuildContext mbc = new MacroBuildContext(this, args, bc);

             return ((Builder) macroBody).build(mbc);

         }

         else

             return macroBody;

     }

 }