/*

  * Copyright 2007-2008 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.rule;

 import java.io.StringReader;

 import java.util.ArrayList;

 import java.util.HashMap;

 import java.util.List;

 import java.util.Map;

 import javax.xml.xpath.XPath;

 import javax.xml.xpath.XPathConstants;

 import javax.xml.xpath.XPathExpressionException;

 import org.apache.commons.lang.StringUtils;

 import org.kuali.rice.kew.api.WorkflowRuntimeException;

 import org.kuali.rice.kew.engine.RouteContext;

 import org.kuali.rice.kew.identity.Id;

 import org.kuali.rice.kew.routeheader.DocumentContent;

 import org.kuali.rice.kew.rule.bo.RuleAttribute;

 import org.kuali.rice.kew.rule.xmlrouting.GenericXMLRuleAttribute;

 import org.kuali.rice.kew.rule.xmlrouting.XPathHelper;

 import org.w3c.dom.Element;

 import org.w3c.dom.NodeList;

 import org.xml.sax.InputSource;

 /**

  * A generic Role Attribute superclass that can be used to route to an ID. Can

  * take as configuration the label to use for the element name in the XML. This

  * allows for re-use of this component in different contexts.

  * 

  * @author Kuali Rice Team (rice.collab@kuali.org)

  */

 public abstract class AbstractIdRoleAttribute extends AbstractRoleAttribute

                 implements GenericXMLRuleAttribute {

         private static final String XML_ELEMENT_LABEL = "xmlElementLabel";

         private static final String ROLE_NAME_LABEL = "roleNameLabel";

         private String idValue;

         private Map paramMap = new HashMap();

         private RuleAttribute ruleAttribute;

         protected abstract String getAttributeElementName();

         protected abstract Id resolveId(String id);

         protected abstract String getIdName();

         /**

          * Returns qualified role names based on IDs in the XML. Each returned

          * qualified Role contains a single ID.

          * 

          * @see org.kuali.rice.kew.rule.RoleAttribute#getQualifiedRoleNames(java.lang.String,

          *      org.kuali.rice.kew.routeheader.DocumentContent)

          */

         public List<String> getQualifiedRoleNames(String roleName,

                         DocumentContent documentContent) {

                 try {

                         readConfiguration();

                         String elementName = (String) getParamMap().get(XML_ELEMENT_LABEL);

                         List<String> qualifiedRoleNames = new ArrayList<String>();

                         XPath xPath = XPathHelper.newXPath();

                         NodeList idNodes = (NodeList) xPath.evaluate("//"

                                         + getAttributeElementName() + "/" + elementName,

                                         documentContent.getDocument(), XPathConstants.NODESET);

                         for (int index = 0; index < idNodes.getLength(); index++) {

                                 Element idElement = (Element) idNodes.item(index);

                                 String id = idElement.getTextContent();

                                 qualifiedRoleNames.add(id);

                         }

                         return qualifiedRoleNames;

                 } catch (XPathExpressionException e) {

                         throw new WorkflowRuntimeException(

                                         "Failed to evaulate XPath expression to find ids.", e);

                 }

         }

         /**

          * Takes the given qualified role which contains an ID and returns a

          * resolved role for the entity with that id.

          * 

          * @see org.kuali.rice.kew.rule.RoleAttribute#resolveQualifiedRole(org.kuali.rice.kew.engine.RouteContext,

          *      java.lang.String, java.lang.String)

          */

         public ResolvedQualifiedRole resolveQualifiedRole(

                         RouteContext routeContext, String roleName, String qualifiedRole) {

                 String roleNameLabel = (String) getParamMap().get(ROLE_NAME_LABEL);

                 if (roleNameLabel == null) {

                         readConfiguration();

                         roleNameLabel = (String) getParamMap().get(ROLE_NAME_LABEL);

                 }

                 ResolvedQualifiedRole resolvedRole = new ResolvedQualifiedRole();

                 resolvedRole.setQualifiedRoleLabel(roleNameLabel);

                 resolvedRole.getRecipients().add(resolveId(qualifiedRole));

                 return resolvedRole;

         }

         /**

          * Generates XML containing the ID on this attribute.

          * 

          * @see org.kuali.rice.kew.rule.AbstractWorkflowAttribute#getDocContent()

          */

         @Override

         public String getDocContent() {

                 readConfiguration();

                 if (!StringUtils.isBlank(getIdValue())) {

                         String elementName = (String) getParamMap().get(XML_ELEMENT_LABEL);

                         return "<" + getAttributeElementName() + "><" + elementName + ">"

                                         + getIdValue() + "</" + elementName + "></"

                                         + getAttributeElementName() + ">";

                 }

                 return "";

         }

         /**

          * Reads any configured values in the XML of the RuleAttribute and adds them

          * to the paramMap.

          * 

          */

         protected void readConfiguration() {

                 String idInMap = (String) getParamMap().get(getIdName());

                 if (getIdValue() == null) {

                         setIdValue(idInMap);

                 }

                 if (getIdValue() != null) {

                         getParamMap().put(getIdName(), getIdValue());

                 }

                 if (ruleAttribute != null) {

                         String xmlConfigData = ruleAttribute.getXmlConfigData();

                         if (!StringUtils.isBlank(xmlConfigData)) {

                                 XPath xPath = XPathHelper.newXPath();

                                 try {

                                         String xmlElementLabel = xPath.evaluate("/configuration/"

                                                         + XML_ELEMENT_LABEL, new InputSource(

                                                         new StringReader(xmlConfigData)));

                                         String roleNameLabel = xPath.evaluate("/configuration/"

                                                         + ROLE_NAME_LABEL, new InputSource(

                                                         new StringReader(xmlConfigData)));

                                         if (!StringUtils.isBlank(xmlElementLabel)) {

                                                 getParamMap().put(XML_ELEMENT_LABEL, xmlElementLabel);

                                         }

                                         if (!StringUtils.isBlank(roleNameLabel)) {

                                                 getParamMap().put(ROLE_NAME_LABEL, roleNameLabel);

                                         }

                                 } catch (XPathExpressionException e) {

                                         throw new WorkflowRuntimeException(

                                                         "Failed to locate Rule Attribute configuration.");

                                 }

                         }

                 }

                 // setup default values if none were defined in XML

                 if (StringUtils.isBlank((String) getParamMap().get(XML_ELEMENT_LABEL))) {

                         getParamMap().put(XML_ELEMENT_LABEL, getIdName());

                 }

                 if (getParamMap().get(ROLE_NAME_LABEL) == null) {

                         getParamMap().put(ROLE_NAME_LABEL, "");

                 }

         }

         public String getIdValue() {

                 return this.idValue;

         }

         public void setIdValue(String idValue) {

                 this.idValue = idValue;

         }

         public Map getParamMap() {

                 return paramMap;

         }

         public void setParamMap(Map paramMap) {

                 this.paramMap = paramMap;

         }

         public void setRuleAttribute(RuleAttribute ruleAttribute) {

                 this.ruleAttribute = ruleAttribute;

         }

 }