/**
    * 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.kcb.config;
  
  import org.kuali.rice.kcb.service.GlobalKCBServiceLocator;
  import org.kuali.rice.ksb.service.KSBServiceLocator;
  import org.quartz.JobDetail;
  import org.quartz.ObjectAlreadyExistsException;
  import org.quartz.Scheduler;
  import org.quartz.SchedulerException;
  import org.quartz.Trigger;
  import org.springframework.beans.BeansException;
  import org.springframework.beans.factory.BeanFactory;
  import org.springframework.beans.factory.BeanFactoryAware;
  import org.springframework.beans.factory.DisposableBean;
  import org.springframework.beans.factory.InitializingBean;
  import org.springframework.beans.factory.annotation.Required;
  
  /**
   * Initializing bean that initializes KCB (specifically the GlobalKCBServiceLocator)
   * on Spring context initialization.  This bean should be eagerly initialized (not marked lazy) 
   * 
   * @author Kuali Rice Team (rice.collab@kuali.org)
   */
  public class KCBInitializer implements BeanFactoryAware, InitializingBean, DisposableBean {
      private BeanFactory beanFactory;
      private Trigger messageProcessingTrigger;
      private JobDetail messageProcessingJobDetail;
      protected Scheduler scheduler;
      
  	/**
       * @see org.springframework.beans.factory.BeanFactoryAware#setBeanFactory(org.springframework.beans.factory.BeanFactory)
       */
      public void setBeanFactory(BeanFactory beanFactory) throws BeansException {
          this.beanFactory = beanFactory;
      }
  
      /**
       * Sets the Trigger for the message processing job
       * @param messageProcessingTrigger the Trigger for the message processing job
       */
      @Required
      public void setMessageProcessingTrigger(Trigger messageProcessingTrigger) {
          this.messageProcessingTrigger = messageProcessingTrigger;
      }
      
      /**
       * Sets the JobDetail for the message processing job
       * @param messageProcessingJobDetail the JobDetail for the message processing job
       */
      @Required
      public void setMessageProcessingJobDetail(JobDetail messageProcessingJobDetail) {
          this.messageProcessingJobDetail = messageProcessingJobDetail;
      }
  
      /**
       * @see org.springframework.beans.factory.InitializingBean#afterPropertiesSet()
       */
      public void afterPropertiesSet() throws Exception {
          GlobalKCBServiceLocator.init(beanFactory);
          // kill the reference, our job is done
          beanFactory = null;
  
          Scheduler scheduler = getScheduler()==null?KSBServiceLocator.getScheduler():getScheduler();
          scheduler.addJob(messageProcessingJobDetail, true);
  
          addTriggerToScheduler(messageProcessingTrigger);
      }
      
      private void addTriggerToScheduler(Trigger trigger) throws SchedulerException {
  		boolean triggerExists = (getScheduler().getTrigger(trigger.getName(), trigger.getGroup()) != null);
  		if (!triggerExists) {
  			try {
  				getScheduler().scheduleJob(trigger);
  			} catch (ObjectAlreadyExistsException ex) {
  				getScheduler().rescheduleJob(trigger.getName(), trigger.getGroup(), trigger);
  			}
  		} else {
  		    getScheduler().rescheduleJob(trigger.getName(), trigger.getGroup(), trigger);
  		}
  	}
  
      public void destroy() throws Exception {
          // prevent anything from accessing our services after the module has been destroyed/shutdown
          // our module's lifecycle is tied to the Spring context lifecycle for now
          GlobalKCBServiceLocator.destroy();
     }
 
 	/**
 	 * @return the scheduler
 	 */
 	public Scheduler getScheduler() {
 		return this.scheduler;
 	}
 
 	/**
 	 * @param scheduler the scheduler to set
 	 */
 	public void setScheduler(Scheduler scheduler) {
 		this.scheduler = scheduler;
 	}
     
 }