/*

  * Copyright 2006-2011 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.ksb.messaging.serviceproxies;

 import org.apache.log4j.Logger;

 import org.kuali.rice.core.api.exception.RiceRuntimeException;

 import org.kuali.rice.core.api.util.ClassLoaderUtils;

 import org.kuali.rice.core.api.util.reflect.BaseInvocationHandler;

 import org.kuali.rice.core.api.util.reflect.TargetedInvocationHandler;

 import org.kuali.rice.core.impl.resourceloader.ContextClassLoaderProxy;

 import org.kuali.rice.ksb.api.bus.Endpoint;

 import org.kuali.rice.ksb.api.bus.ServiceConfiguration;

 import org.kuali.rice.ksb.api.messaging.AsynchronousCall;

 import org.kuali.rice.ksb.messaging.PersistedMessageBO;

 import org.kuali.rice.ksb.messaging.quartz.MessageServiceExecutorJob;

 import org.kuali.rice.ksb.messaging.quartz.MessageServiceExecutorJobListener;

 import org.kuali.rice.ksb.service.KSBServiceLocator;

 import org.quartz.JobDataMap;

 import org.quartz.JobDetail;

 import org.quartz.Scheduler;

 import org.quartz.SchedulerException;

 import org.quartz.SimpleTrigger;

 import org.quartz.Trigger;

 import java.io.Serializable;

 import java.lang.reflect.Method;

 import java.lang.reflect.Proxy;

 import java.sql.Timestamp;

 import java.util.Calendar;

 import java.util.List;

 /**

  * A proxy which schedules a service to be executed asynchronously after some delay period.

  * 

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

  */

 public class DelayedAsynchronousServiceCallProxy extends BaseInvocationHandler implements TargetedInvocationHandler {

     private static final Logger LOG = Logger.getLogger(DelayedAsynchronousServiceCallProxy.class);

     List<Endpoint> endpoints;

     private Serializable context;

     private String value1;

     private String value2;

     private long delayMilliseconds;

     protected DelayedAsynchronousServiceCallProxy(List<Endpoint> endpoints, Serializable context,

             String value1, String value2, long delayMilliseconds) {

         this.endpoints = endpoints;

         this.context = context;

         this.value1 = value1;

         this.value2 = value2;

         this.delayMilliseconds = delayMilliseconds;

     }

     public static Object createInstance(List<Endpoint> endpoints, Serializable context, String value1,

             String value2, long delayMilliseconds) {

         if (endpoints == null || endpoints.isEmpty()) {

             throw new RuntimeException("Cannot create service proxy, no service(s) passed in.");

         }

         try {

             return Proxy.newProxyInstance(ClassLoaderUtils.getDefaultClassLoader(), ContextClassLoaderProxy

                     .getInterfacesToProxy(endpoints.get(0).getService()),

                     new DelayedAsynchronousServiceCallProxy(endpoints, context, value1, value2, delayMilliseconds));

         } catch (Exception e) {

             throw new RiceRuntimeException(e);

         }

     }

     @Override

     protected Object invokeInternal(Object proxy, Method method, Object[] arguments) throws Throwable {

         // there are multiple service calls to make in the case of topics.

         AsynchronousCall methodCall = null;

         PersistedMessageBO message = null;

         synchronized (this) {

             // consider moving all this topic invocation stuff to the service

             // invoker for speed reasons

             for (Endpoint endpoint : this.endpoints) {

                 ServiceConfiguration serviceConfiguration = endpoint.getServiceConfiguration();

                 methodCall = new AsynchronousCall(method.getParameterTypes(), arguments, serviceConfiguration, method.getName(),

                         null, this.context);

                 message = KSBServiceLocator.getMessageQueueService().getMessage(serviceConfiguration, methodCall);

                 message.setValue1(this.value1);

                 message.setValue2(this.value2);

                 Calendar now = Calendar.getInstance();

                 now.add(Calendar.MILLISECOND, (int) delayMilliseconds);

                 message.setQueueDate(new Timestamp(now.getTimeInMillis()));

                 scheduleMessage(message);

                 // only do one iteration if this is a queue. The load balancing

                 // will be handled when the service is

                 // fetched by the MessageServiceInvoker through the GRL (and

                 // then through the RemoteResourceServiceLocatorImpl)

                 if (serviceConfiguration.isQueue()) {

                     break;

                 }

             }

         }

         return null;

     }

     protected void scheduleMessage(PersistedMessageBO message) throws SchedulerException {

         LOG.debug("Scheduling execution of a delayed asynchronous message.");

         Scheduler scheduler = KSBServiceLocator.getScheduler();

         JobDataMap jobData = new JobDataMap();

         jobData.put(MessageServiceExecutorJob.MESSAGE_KEY, message);

         JobDetail jobDetail = new JobDetail("Delayed_Asynchronous_Call-" + Math.random(), "Delayed_Asynchronous_Call",

                 MessageServiceExecutorJob.class);

         jobDetail.setJobDataMap(jobData);

         jobDetail.addJobListener(MessageServiceExecutorJobListener.NAME);

         Trigger trigger = new SimpleTrigger("Delayed_Asynchronous_Call_Trigger-" + Math.random(),

                 "Delayed_Asynchronous_Call", message.getQueueDate());

         trigger.setJobDataMap(jobData);// 1.6 bug required or derby will choke

         scheduler.scheduleJob(jobDetail, trigger);

     }

     /**

          * Returns the List<RemotedServiceHolder> of asynchronous services which will be invoked by calls to this proxy.

          * This is a List because, in the case of Topics, there can be more than one service invoked.

          */

     public Object getTarget() {

         return this.endpoints;

     }

 }