/**
    * Copyright 2005-2011 The Kuali Foundation
    *
    * Licensed under the Educational Community License, Version 2.0 (the "License");
    * you may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    *
    * http://www.opensource.org/licenses/ecl2.php
    *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.kuali.rice.kew.engine.node.var;
  
  import org.apache.log4j.Logger;
  import org.kuali.rice.core.api.util.xml.XmlException;
  import org.kuali.rice.kew.engine.RouteContext;
  import org.kuali.rice.kew.engine.RouteHelper;
  import org.kuali.rice.kew.engine.node.BranchState;
  import org.kuali.rice.kew.engine.node.PropertiesUtil;
  import org.kuali.rice.kew.engine.node.SimpleNode;
  import org.kuali.rice.kew.engine.node.SimpleResult;
  import org.kuali.rice.kew.service.KEWServiceLocator;
  import org.w3c.dom.Document;
  import org.w3c.dom.Element;
  import org.xml.sax.InputSource;
  
  import javax.xml.parsers.DocumentBuilder;
  import javax.xml.parsers.DocumentBuilderFactory;
  import java.io.StringReader;
  
  
  /**
   * A simple node that allows setting of document variables.
   * The definition of SetVarNode takes the following config parameter elements:
   * <dl>
   *   <dt>name</dt>
   *   <dd>The name of the variable to set</dd>
   *   <dt>value</dt>
   *   <dd>The value to which to set the variable.  This value is parsed according to
   *       Property/PropertyScheme syntax</dd>
   * </dl>
   * The default PropertySchme is LiteralScheme, which will evaluate the value simply
   * as a literal (won't do anything but return it)
   * @see PropertyScheme
   * @see Property
   * 
   * @author Kuali Rice Team (rice.collab@kuali.org)
   */
  public class SetVarNode implements SimpleNode {
      private static final Logger LOG = Logger.getLogger(SetVarNode.class);
  
      public SimpleResult process(RouteContext context, RouteHelper helper) throws Exception {
          LOG.debug("processing");
          DocumentBuilder db = DocumentBuilderFactory.newInstance().newDocumentBuilder();
          String contentFragment = context.getNodeInstance().getRouteNode().getContentFragment();
          LOG.debug("contentFragment=" + contentFragment);
          Document d = db.parse(new InputSource(new StringReader(contentFragment)));
          Element e = d.getDocumentElement();
          String name = e.getElementsByTagName("name").item(0).getTextContent();
          // FIXME: validation should be checked in documenttypexmlparser to start with
          if (name == null) {
              throw new XmlException("SetVar node required 'name' attribute to be specified");
          }
          String valueRef = e.getElementsByTagName("value").item(0).getTextContent();
          Object retrievedVal = PropertiesUtil.retrieveProperty(valueRef, PropertyScheme.LITERAL_SCHEME, context);
          LOG.debug("retrieved value '" + retrievedVal + " for value '" + valueRef);
          // hack to make variable value fit in column size
          // need to just alter that column
          String stringVal = null;
          if (retrievedVal != null) {
              stringVal = retrievedVal.toString();
              if (stringVal.length() > 255) {
                  stringVal = stringVal.substring(0, 255);
              }
          }
          LOG.debug("setting value '" + stringVal + "' for variable " + name);
          KEWServiceLocator.getBranchService().setScopedVariableValue(context.getNodeInstance().getBranch(), BranchState.VARIABLE_PREFIX + name, stringVal);
  
          return new SimpleResult(true);
      }
  
  }