/*

  * Copyright (C) 2005 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.directive;

 import java.io.IOException;

 import org.webmacro.Context;

 import org.webmacro.FastWriter;

 import org.webmacro.Macro;

 import org.webmacro.PropertyException;

 import org.webmacro.TemplateVisitor;

 import org.webmacro.WebMacroException;

 import org.webmacro.engine.BuildContext;

 import org.webmacro.engine.BuildException;

 import org.webmacro.engine.StringTemplate;

 import org.webmacro.engine.Variable;

 import org.webmacro.servlet.TextTool;

 import org.webmacro.util.Instantiator;

 /**

  * Set properties on an object using Java properties file

  * type syntax.

  * 

  * @author Keats Kirsch 

  */

 public class SetpropsDirective extends Directive

 {

     private static final String DEFAULT_CLASS_NAME = "java.util.Hashtable";

     private static final int PROPS_TARGET = 1;

     private static final int PROPS_CLASS = 2;

     private static final int PROPS_CLASSNAME = 3;

     private static final int PROPS_RESULT = 4;

     private Variable target;

     private Object result;

     private String _className;

     private static final ArgDescriptor[] myArgs = new ArgDescriptor[] {

             new LValueArg(PROPS_TARGET), new OptionalGroup(3),

             new KeywordArg(PROPS_CLASS, "class"), new AssignmentArg(),

             new QuotedStringArg(PROPS_CLASSNAME), new BlockArg(PROPS_RESULT) };

     private static final DirectiveDescriptor myDescr = new DirectiveDescriptor(

             "setprops", null, myArgs, null);

     public static DirectiveDescriptor getDescriptor ()

     {

         return myDescr;

     }

     public SetpropsDirective()

     {

     }

     public Object build (DirectiveBuilder builder, BuildContext bc)

             throws BuildException

     {

         try {

             target = (Variable) builder.getArg(PROPS_TARGET, bc);

         } catch (ClassCastException e) {

             throw new NotVariableBuildException(myDescr.name, e);

         }

         _className = (String) builder.getArg(PROPS_CLASSNAME, bc);

         if (_className == null)

             _className = DEFAULT_CLASS_NAME;

         result = builder.getArg(PROPS_RESULT, bc);

         return this;

     }

     public void write (FastWriter out, Context context)

             throws PropertyException, IOException

     {

         try {

             if (!context.containsKey(target.getName())) {

                 // target doesn't exist. Must create.

                 // TODO check for class loading restrictions as per bean directive

                 try {

                     Class c = Instantiator.getInstance(context.getBroker())

                             .classForName(_className);

                     Object o = c.newInstance();

                     target.setValue(context, o);

                 } catch (RuntimeException re) {

                     throw new PropertyException("Failed to create instance of "

                             + _className + " for the #properties directive. "

                             + re, re);

                 }

             }

             String res = (String) ((Macro) result).evaluate(context);

             String[] lines = TextTool.getLines(res);

             String s;

             String prevLine = "";

             String prefix = "#set $" + target.getVariableName() + ".";

             for (int i = 0; i < lines.length; i++) {

                 s = prevLine + lines[i].trim();

                 if (s.endsWith("\\")) {

                     // ends with continuation character. Add to next line.

                     prevLine = s.substring(0, s.length() - 1);

                 } else {

                     prevLine = "";

                     setProp(context, s, prefix);

                 }

             }

         } catch (PropertyException e) {

             throw e;

         } catch (Exception e) {

             String errorText = "#setprops: Unable to set " + target + " as " + e.getMessage();

             writeWarning(errorText, context, out);

         }

     }

     private void setProp (Context context, String s, String prefix)

             throws PropertyException

     {

         String prop;

         String val;

         StringTemplate stringTemplate;

         if (s.length() > 0 && !s.startsWith("#")) {

             for (int j = 0; j < s.length(); j++) {

                 char ch = s.charAt(j);

                 if (ch == ':' || ch == '=') {

                     prop = s.substring(0, j).trim();

                     val = s.substring(j + 1).trim();

                     // convert to WM syntax and evaluate

                     // if (val.length() > 0)

                     // {

                     // try first as a string

                     s = prefix + prop + "=\"" + val + "\"";

                     try {

                         stringTemplate = new StringTemplate(context.getBroker(), s);

                         stringTemplate.evaluateAsString(context);

                     } catch (WebMacroException wme) {

                         // try again without quotes.

                         s = prefix + prop + "=" + val;

                         try {

                             stringTemplate = new StringTemplate(context.getBroker(), s);

                             stringTemplate.evaluateAsString(context);

                         } catch (WebMacroException wme2) {

                             PropertyException pex = new PropertyException(

                                     "Failed to set property \"" + prop

                                             + "\" to value \"" + val

                                             + "\" on variable \""

                                             + target.getVariableName()

                                             + "\" of type "

                                             + target.getClass().getName(), wme2);

                             context.getEvaluationExceptionHandler().evaluate(

                                     this.target, context, pex);

                         }

                     }

                     break;

                 }

             }

         }

     }

     public void accept (TemplateVisitor v)

     {

         v.beginDirective(myDescr.name);

         v.visitDirectiveArg("PropertiesClassKeyword", "class");

         v.visitDirectiveArg("PropertiesClassName", _className);

         v.visitDirectiveArg("PropertiesTarget", target);

         v.visitDirectiveArg("PropertiesValue", result);

         v.endDirective();

     }

 }