package com.atlassian.sal.core.scheduling;
   
   import com.atlassian.sal.api.scheduling.PluginJob;
   import com.atlassian.sal.api.scheduling.PluginScheduler;
   import org.slf4j.Logger;
   import org.slf4j.LoggerFactory;
   
   import java.util.Collections;
   import java.util.Date;
  import java.util.HashMap;
  import java.util.Map;
  import java.util.Timer;
  import java.util.TimerTask;
  
  /**
   * Plugin scheduler that uses java.util.Timer
   */
  public class TimerPluginScheduler implements PluginScheduler
  {
  
      private final Map<String, Timer> tasks;
      private final boolean useDaemons;
  
      public TimerPluginScheduler()
      {
          this(Collections.synchronizedMap(new HashMap<String, Timer>()), false);
      }
  
      protected TimerPluginScheduler(Map<String, Timer> tasks, boolean useDaemons)
      {
          this.tasks = tasks;
          this.useDaemons = useDaemons;
      }
  
      public synchronized void scheduleJob(final String name, final Class<? extends PluginJob> job, final Map<String, Object> jobDataMap, final Date startTime, final long repeatInterval)
      {
          // Use one timer per task, this will allow us to remove them if that functionality is wanted in future
          Timer timer = tasks.get(name);
          PluginTimerTask task;
          if (timer != null)
          {
              timer.cancel();
          }
          timer = new Timer("PluginSchedulerTask-" + name, useDaemons);
          tasks.put(name, timer);
          task = new PluginTimerTask();
          task.setJobClass(job);
          task.setJobDataMap(jobDataMap);
          timer.scheduleAtFixedRate(task, startTime, repeatInterval);
      }
  
      /**
       * TimerTask that executes a PluginJob
       */
      private static class PluginTimerTask extends TimerTask
      {
          private Class<? extends PluginJob> jobClass;
          private Map<String, Object> jobDataMap;
          private static final Logger log = LoggerFactory.getLogger(PluginTimerTask.class);
  
          @Override
  		public void run()
          {
              PluginJob job;
              try
              {
                  job = jobClass.newInstance();
              }
              catch (final InstantiationException ie)
              {
                  log.error("Error instantiating job", ie);
                  return;
              }
              catch (final IllegalAccessException iae)
              {
                  log.error("Cannot access job class", iae);
                  return;
              }
              job.execute(jobDataMap);
          }
  
          public Class<? extends PluginJob> getJobClass()
          {
              return jobClass;
          }
  
          public void setJobClass(final Class<? extends PluginJob> jobClass)
          {
              this.jobClass = jobClass;
          }
  
          public Map<String, Object> getJobDataMap()
          {
              return jobDataMap;
          }
  
          public void setJobDataMap(final Map<String, Object> jobDataMap)
          {
              this.jobDataMap = jobDataMap;
         }
     }
 
 	public void unscheduleJob(final String name)
 	{
         final Timer timer = tasks.remove(name);
         if (timer != null)
         {
             timer.cancel();
         }
         else
         {
             throw new IllegalArgumentException("Attempted to unschedule unknown job: " + name);
         }
     }
 }