/**

  * 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.core.messages.dao.impl;

 import java.util.ArrayList;

 import java.util.List;

 import javax.persistence.EntityManager;

 import javax.persistence.PersistenceContext;

 import javax.persistence.Query;

 import org.kuali.student.core.messages.MessageException;

 import org.kuali.student.core.messages.dao.MessageManagementDAO;

 import org.kuali.student.core.messages.entity.MessageEntity;

 import org.slf4j.Logger;

 import org.slf4j.LoggerFactory;

 public class MessageManagementDAOImpl implements MessageManagementDAO {

     private EntityManager entityManager;

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

     @PersistenceContext(unitName = "MessageManagement")

     public void setEntityManager(EntityManager entityManager) {

         this.entityManager = entityManager;

     }

     public EntityManager getEntityManager(){

         return this.entityManager; 

     }

     public MessageEntity addMessage(MessageEntity me){

             MessageEntity result = null;

             try{

                 entityManager.persist(me);

                 result = this.getMessage(me.getLocale(), me.getGroupName(), me.getId());

             }

                 catch(Exception e){

                     throw new MessageException("adding message data query failed.", e);

                 }

                 return result;

     }

     public int getTotalMessages(){

             int count = 0;

             try{

                 Query query = entityManager.createQuery("SELECT COUNT(m) FROM MessageEntity m");

                 count = ((Long)query.getSingleResult()).intValue();

             }

         catch(Exception e){

                     logger.error("count query failed.", e);

                         throw new MessageException("count query failed.", e);

             }

         return count;

     }

         @SuppressWarnings("unchecked")

         public List<String> getLocales() {

                 List<String> locales;

             try{

                 Query query = entityManager.createQuery("SELECT distinct m.locale FROM MessageEntity m");

                 locales = (List<String>) query.getResultList();

             }

         catch(Exception e){

                     logger.error("getLocales query failed.", e);

                         throw new MessageException("getLocales query failed.", e);

             }

                 return locales;

         }

         @SuppressWarnings("unchecked")

         public List<String> getMessageGroups() {

                 List<String> groups;

             try{

                 Query query = entityManager.createQuery("SELECT distinct m.groupName FROM MessageEntity m");

                 groups = (List<String>) query.getResultList();

             }

         catch(Exception e){

                     logger.error("getMessageGroups query failed.", e);

                         throw new MessageException("getMessageGroups query failed.", e);

             }

                 return groups;

         }

         public MessageEntity getMessage(String locale, String groupKey, String messageKey) {

                 MessageEntity entity = null;

                 try{

                         Query query = entityManager.createQuery(

                                 "select m from MessageEntity m " +

                                 "where m.locale = :locale and " +

                                 "m.groupName = :groupKey and " +

                                 "m.messageId = :messageKey");

                          query.setParameter("locale", locale);

                          query.setParameter("groupKey", groupKey);

                          query.setParameter("messageKey", messageKey);

                          if(!query.getResultList().isEmpty()){

                             entity = (MessageEntity)query.getResultList().get(0);

                          }else{

                             return null;

                          }

                 }

                 catch(Exception e){

                         logger.error("getMessage query failed.", e);

                         throw new MessageException("getMessage query failed.", e);

                 }

                 return entity;

         }

         @SuppressWarnings("unchecked")

         public List<MessageEntity> getMessages(String locale, String groupKey) {

                 List<MessageEntity> list;

                 try{

                         Query query = entityManager.createQuery(

                             "select m from MessageEntity m " +

                             "where m.locale = :locale and " +

                             "m.groupName = :groupKey ");

                          query.setParameter("locale", locale);

                          query.setParameter("groupKey", groupKey);

                          list = (List<MessageEntity>)query.getResultList();

                 }

                 catch(Exception e){

                         logger.error("getMessages query failed.", e);

                         throw new MessageException("getMessages query failed.", e);

                 }

                 return list;

         }

         @SuppressWarnings("unchecked")

         public List<MessageEntity> getMessagesByGroups(String locale, List<String> groupKeys) {

                 List<MessageEntity> list = new ArrayList<MessageEntity>();

                 try{

                         for(String currentKey: groupKeys){

                                 Query query = entityManager.createQuery(

                                     "select m from MessageEntity m " +

                                     "where m.locale = :locale and " +

                                     "m.groupName = :groupKey ");

                                  query.setParameter("locale", locale);

                                  query.setParameter("groupKey", currentKey);

                                  list.addAll((List<MessageEntity>)query.getResultList());

                         }

                 }

                 catch(Exception e){

                         logger.error("getMessagesByGroups query failed.", e);

                         throw new MessageException("getMessagesByGroups query failed.", e);

                 }

                 return list;

         }

         //assuming all keys are staying the same

         public MessageEntity updateMessage(String locale, String groupKey, String messageKey, MessageEntity updatedMessage) {

                 MessageEntity returnValue = null;

             try{

                     MessageEntity theEntity = this.getMessage(locale, groupKey, messageKey);

                 if(theEntity != null){

                         theEntity.setValue(updatedMessage.getValue());

                         theEntity.setMessageId(updatedMessage.getMessageId());

                         theEntity.setLocale(updatedMessage.getLocale());

                         theEntity.setGroupName(updatedMessage.getGroupName());

                         entityManager.merge(theEntity);

                         returnValue = theEntity;

                 }

             }

         catch(Exception e){

                         throw new MessageException("updateMessage query failed.", e);

         }

         return returnValue;

         }

 }