/**

  * Copyright 2010 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.osedu.org/licenses/ECL-2.0

  *

  * 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.student.common.util.jpa;

 import java.io.BufferedReader;

 import java.io.File;

 import java.io.FileReader;

 import java.io.IOException;

 import java.util.List;

 import java.util.Map;

 import java.util.Map.Entry;

 import javax.persistence.EntityManager;

 import javax.persistence.EntityManagerFactory;

 import org.apache.commons.lang.StringUtils;

 import org.slf4j.Logger;

 import org.slf4j.LoggerFactory;

 import org.springframework.beans.BeansException;

 import org.springframework.context.ApplicationContext;

 import org.springframework.context.ApplicationContextAware;

 import org.springframework.context.ApplicationEvent;

 import org.springframework.context.ApplicationListener;

 import org.springframework.context.event.ContextRefreshedEvent;

 import org.springframework.core.io.ClassPathResource;

 import org.springframework.orm.jpa.EntityManagerFactoryUtils;

 import org.springframework.orm.jpa.SharedEntityManagerCreator;

 import org.springframework.transaction.TransactionDefinition;

 import org.springframework.transaction.TransactionStatus;

 import org.springframework.transaction.jta.JtaTransactionManager;

 import org.springframework.transaction.support.DefaultTransactionDefinition;

 public class LoadSqlListener implements ApplicationListener,

                 ApplicationContextAware {

         final static Logger logger = LoggerFactory.getLogger(LoadSqlListener.class);

         private ApplicationContext applicationContext;

         private boolean loaded = false;

         private Map<String,Object> preloadMap;

         private JtaTransactionManager jtaTxManager;

         private boolean shouldLoadData = false;

         @Override

         @SuppressWarnings("unchecked") 

         public void onApplicationEvent(ApplicationEvent event) {

                 if (event instanceof ContextRefreshedEvent && !loaded && shouldLoadData) {

                         for (Entry<String, Object> entry : preloadMap.entrySet()) {

                                 if(entry.getValue() instanceof java.util.List<?>) {

                                         List<String> sqlFileList = (List<String>) entry.getValue();

                                         for(String sqlFile : sqlFileList) {

                                                 process(entry.getKey(), sqlFile);

                                         }

                                 } else {

                                         process(entry.getKey(), entry.getValue().toString());

                                 }

                         }

                         loaded=true;

                 }

         }

         private void process(String entityKey, String sqlFileName) {

                 EntityManagerFactory emf = EntityManagerFactoryUtils

                                 .findEntityManagerFactory(applicationContext, entityKey);

                 EntityManager em = SharedEntityManagerCreator

                                 .createSharedEntityManager(emf);

                 File sqlFile;

                 BufferedReader in;

                 try{

                     if(sqlFileName.startsWith("classpath:")){

                                   sqlFile = new ClassPathResource(sqlFileName.substring("classpath:".length())).getFile();

                         }else{

                             sqlFile = new File(sqlFileName);

                     }

                         in = new BufferedReader(new FileReader(sqlFile));

                 } catch (Exception e) {

                         throw new RuntimeException(e);

                 }

                 String ln = "";

                 TransactionDefinition txDefinition = new DefaultTransactionDefinition() ;

                 TransactionStatus txStatus = jtaTxManager.getTransaction(txDefinition);

                 try {

                         while((ln=in.readLine())!=null){

                                 if(!ln.startsWith("/")&&!ln.startsWith("--")&&StringUtils.isNotBlank(ln)){

                                         ln=ln.replaceFirst("[;/]\\s*$","");

                                         em.createNativeQuery(ln).executeUpdate();

                                 }

                         }

                         jtaTxManager.commit(txStatus);

                 } catch (Exception e) {

                         logger.error("Error loading sql file "+sqlFileName+". Failing statement was '" + ln + "'",e);

                         jtaTxManager.rollback(txStatus);

                 }

                 finally{

                         try {

                                 in.close();

                         } catch (IOException e) {

                                 logger.error("IO Stream closed " + e);

                         }

                 }

         }

         @Override

         public void setApplicationContext(ApplicationContext applicationContext)

                         throws BeansException {

                 this.applicationContext = applicationContext;

         }

         public JtaTransactionManager getJtaTxManager() {

                 return jtaTxManager;

         }

         public void setJtaTxManager(JtaTransactionManager jtaTxManager) {

                 this.jtaTxManager = jtaTxManager;

         }

         public Map<String, Object> getPreloadMap() {

                 return preloadMap;

         }

         public void setPreloadMap(Map<String, Object> preloadMap) {

                 this.preloadMap = preloadMap;

         }

         public void setShouldLoadData(boolean shouldLoadData) {

                 this.shouldLoadData = shouldLoadData;

         }

 }