/*******************************************************************************
    *  Imixs Workflow 
    *  Copyright (C) 2001, 2011 Imixs Software Solutions GmbH,  
    *  http://www.imixs.com
    *  
    *  This program is free software; you can redistribute it and/or 
    *  modify it under the terms of the GNU General Public License 
    *  as published by the Free Software Foundation; either version 2 
    *  of the License, or (at your option) any later version.
   *  
   *  This program is distributed in the hope that it will be useful, 
   *  but WITHOUT ANY WARRANTY; without even the implied warranty of 
   *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 
   *  General Public License for more details.
   *  
   *  You can receive a copy of the GNU General Public
   *  License at http://www.gnu.org/licenses/gpl.html
   *  
   *  Project: 
   *  	http://www.imixs.org
   *  	http://java.net/projects/imixs-workflow
   *  
   *  Contributors:  
   *  	Imixs Software Solutions GmbH - initial API and implementation
   *  	Ralph Soika - Software Developer
   *******************************************************************************/
  
  package org.imixs.workflow.plugins;
  
  import org.imixs.workflow.ItemCollection;
  import org.imixs.workflow.Plugin;
  import org.imixs.workflow.exceptions.PluginException;
  
  /**
   * This Pluginmodul generates a result message. The Plugin checks if the activiy
   * document has an "txtActivityResult" attribute. The value will be parsed for
   * "<field>attribute</field>" tags and these tags will be replaced with the
   * values of the corresponding attributes of the workitem.
   * 
   * The final result will be stored into the attribute
   * "txtworkflowresultmessage".
   * 
   * This field could be used by an application to display individual messages
   * (e.g HTML Code) or return result Strings (e.g. JSF Action Results)
   * 
   * @author Ralph Soika
   * @version 1.0
   * @see org.imixs.workflow.WorkflowManager
   * 
   */
  public class ResultPlugin extends AbstractPlugin {
  	ItemCollection documentContext;
  	String sActivityResult;
  
  	public int run(ItemCollection adocumentContext,
  			ItemCollection adocumentActivity) throws PluginException {
  		documentContext = adocumentContext;
  
  		// get ResultMessage
  		sActivityResult = adocumentActivity
  				.getItemValueString("txtActivityResult");
  		sActivityResult = replaceDynamicValues(sActivityResult,
  				adocumentContext);
  
  		// evaluate new items....
  		evaluate(sActivityResult, adocumentContext);
  
  		return Plugin.PLUGIN_OK;
  	}
  
  	public void close(int status) throws PluginException {
  		try {
  			// restore changes?
  			if (status < Plugin.PLUGIN_ERROR) {
  				documentContext.replaceItemValue("txtworkflowresultmessage",
  						sActivityResult);
  			}
  		} catch (Exception e) {
  			System.out.println("[ResultPlugin] Error close(): " + e.toString());
  
  		}
  	}
  
  	/**
  	 * This method parses a string for xml tag <item>. Those tags will result in
  	 * new workitem properties.
  	 * 
  	 * <code>
  	 *   
  	 *   <item name="txtTitle">new Title</item>
  	 *   
  	 *   
  	 * </code>
  	 * 
  	 * Additional the attribute 'type' can be provided to specify a field type
  	 * 'boolean', 'string', 'integer'
  	 * 
  	 * The item will be added into the workitem documentContext
  	 * 
 	 * 
 	 */
 	public static void evaluate(String aString, ItemCollection documentContext) {
 		int iTagStartPos;
 		int iTagEndPos;
 
 		int iContentStartPos;
 		int iContentEndPos;
 
 		int iNameStartPos;
 		int iNameEndPos;
 
 		int iTypeStartPos;
 		int iTypeEndPos;
 
 		String sName = "";
 		String sType = " ";
 		String sItemValue;
 
 		if (aString == null)
 			return;
 
 		// test if a <value> tag exists...
 		while ((iTagStartPos = aString.toLowerCase().indexOf("<item")) != -1) {
 
 			iTagEndPos = aString.toLowerCase().indexOf("</item>", iTagStartPos);
 
 			// if no end tag found return string unchanged...
 			if (iTagEndPos == -1)
 				return;
 
 			// reset pos vars
 			iContentStartPos = 0;
 			iContentEndPos = 0;
 			iNameStartPos = 0;
 			iNameEndPos = 0;
 			iTypeStartPos = 0;
 			iTypeEndPos = 0;
 			sName = "";
 			sType = " ";
 			sItemValue = "";
 
 			// so we now search the beginning of the tag content
 			iContentEndPos = iTagEndPos;
 			// start pos is the last > before the iContentEndPos
 			String sTestString = aString.substring(0, iContentEndPos);
 			iContentStartPos = sTestString.lastIndexOf('>') + 1;
 
 			// if no end tag found return string unchanged...
 			if (iContentStartPos >= iContentEndPos)
 				return;
 
 			iTagEndPos = iTagEndPos + "</item>".length();
 
 			// now we have the start and end position of a tag and also the
 			// start and end pos of the value
 
 			// next we check if the start tag contains a 'name' attribute
 			iNameStartPos = aString.toLowerCase()
 					.indexOf("name=", iTagStartPos);
 			// extract format string if available
 			if (iNameStartPos > -1 && iNameStartPos < iContentStartPos) {
 				iNameStartPos = aString.indexOf("\"", iNameStartPos) + 1;
 				iNameEndPos = aString.indexOf("\"", iNameStartPos + 1);
 				sName = aString.substring(iNameStartPos, iNameEndPos);
 			}
 
 			// next we check if the start tag contains a 'type'
 			// attribute
 			iTypeStartPos = aString.toLowerCase()
 					.indexOf("type=", iTagStartPos);
 			// extract format string if available
 			if (iTypeStartPos > -1 && iTypeStartPos < iContentStartPos) {
 				iTypeStartPos = aString.indexOf("\"", iTypeStartPos) + 1;
 				iTypeEndPos = aString.indexOf("\"", iTypeStartPos + 1);
 				sType = aString.substring(iTypeStartPos, iTypeEndPos);
 			}
 
 			// extract Item Value
 			sItemValue = aString.substring(iContentStartPos, iContentEndPos);
 
 			// replace the item value
 			if (sName != null && !"".equals(sName)) {
 				// convert to type...
 				Object oValue = sItemValue;
 
 				if ("boolean".equalsIgnoreCase(sType))
 					// oValue=new Boolean(sItemValue);
 					oValue = Boolean.valueOf(sItemValue);
 
 				if ("integer".equalsIgnoreCase(sType))
 					oValue = new Integer(sItemValue);
 
 				documentContext.replaceItemValue(sName, oValue);
 			}
 
 			// now cut the tag form the string
 			aString = aString.substring(0, iTagStartPos) + ""
 					+ aString.substring(iTagEndPos);
 		}
 
 	}
 
 }