/*

  * Copyright 2007 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.kns.web;

 import java.util.ArrayList;

 import java.util.List;

 import javax.servlet.ServletContext;

 import javax.servlet.ServletContextEvent;

 import javax.servlet.ServletContextListener;

 import org.apache.commons.lang.StringUtils;

 import org.kuali.rice.core.config.Config;

 import org.kuali.rice.core.config.ConfigContext;

 import org.kuali.rice.core.config.JAXBConfigImpl;

 import org.kuali.rice.core.config.SimpleConfig;

 import org.kuali.rice.core.util.JSTLConstants;

 import org.kuali.rice.kew.util.KEWConstants;

 public class RiceConfigurationListener implements ServletContextListener {

     public void contextDestroyed(ServletContextEvent sce) {

     }

     public void contextInitialized(ServletContextEvent sce) {

         sce.getServletContext().setAttribute("Constants", new JSTLConstants(KEWConstants.class));

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

         // use the system prop as an override of the default packaged META-INF/workflow.xml

         String altCoreConfigLocation = System.getProperty(KEWConstants.DEFAULT_CONFIG_LOCATION_PARAM);

         if (altCoreConfigLocation != null) {

             configLocations.add(altCoreConfigLocation);

         }

         else {

             addDefaultConfigLocation(sce.getServletContext(), configLocations);

         }

         // use the system property to add additional configurations (useful for testing)

         String additionalConfigLocations = System.getProperty(KEWConstants.ADDITIONAL_CONFIG_LOCATIONS_PARAM);

         if (!StringUtils.isEmpty(additionalConfigLocations)) {

             String[] additionalConfigLocationArray = additionalConfigLocations.split(",");

             for (String additionalConfigLocation : additionalConfigLocationArray) {

                 configLocations.add(additionalConfigLocation);

             }

         }

         try {

             Config serverConfig = new JAXBConfigImpl(configLocations);

             serverConfig.parseConfig();

             ConfigContext.init(serverConfig);

         }

         catch (Exception e) {

             e.printStackTrace();

             throw new RuntimeException("Workflow failed to start properly.  Exiting.", e);

         }

     }

     /**

      * Configures the default config location by first checking the init params for default locations and then falling back to the

      * standard default config location.

      */

     protected void addDefaultConfigLocation(ServletContext context, List<String> configLocations) {

         String defaultConfigLocation = context.getInitParameter(KEWConstants.DEFAULT_CONFIG_LOCATION_PARAM);

         if (!StringUtils.isEmpty(defaultConfigLocation)) {

             String[] locations = defaultConfigLocation.split(",");

             for (String location : locations) {

                 configLocations.add(location);

             }

         }

         else {

                 // TODO: say what? Why workflow.xml?

             configLocations.add("classpath:META-INF/workflow.xml");

         }

     }

 }