package astrogrid.registry.harvest.daemon;
   
   import java.util.*;
   import java.io.*;
   import javax.servlet.*;
   import javax.servlet.http.*;
   
   
   import org.astrogrid.config.Config;
  import org.astrogrid.registry.server.harvest.RegistryHarvestService;
  import org.astrogrid.registry.RegistryException;
  //import org.apache.axis.AxisFault;
  
  
  public class HarvestDaemon extends HttpServlet //implements Runnable
  {
     //Thread myThread;
     int myCounter;
     int harvestInterval;
     Date lastHarvestTime;
     Date servletInitTime;
     RegistryHarvestService rhs;
     boolean harvestOnLoad = false;
     boolean valuesSet = false;
     public static boolean harvestStarted;
     
     private ServletContext context = null;   
  
     public static final String INTERVAL_HOURS_PROPERTY =
         "org.astrogrid.registry.harvest.daemon.interval-hours";
     public static Config conf = null;
     private Timer timer = null;
     private Timer scheduleTimer = null;
  
     static {
        if(conf == null) {
           conf = org.astrogrid.config.SimpleConfig.getSingleton();
           harvestStarted = false;
        }
     }
     
  
     public void destroy() {
         super.destroy();
         System.out.println("exiting HarvestDaemon; trying to destroy timers");
         if(timer != null) {
             timer.cancel();
         }//if
         if(scheduleTimer != null) {
             scheduleTimer.cancel();
         }
     }
     
     public void init(ServletConfig config)
                  throws ServletException
     {
  	    super.init(config);
        
         System.out.println("initialized HarvestDaemon");
         
         servletInitTime = new Date();
         rhs = new RegistryHarvestService();
         if(scheduleTimer != null) {
             //hmmm just in case the servlet container decides to re-initialize
             //this servlet.
             scheduleTimer.cancel();
             scheduleTimer = null;
         }
         scheduleTimer = new Timer();
         boolean harvestEnabled = conf.getBoolean("registry.harvest.enabled",false);
         if(harvestEnabled) {
            if(!valuesSet) {
                System.out.println("harvest is enabled");
                valuesSet = true;
                harvestInterval = conf.getInt(INTERVAL_HOURS_PROPERTY);
                //lets not start a harvest off the bat, wait till next cycle.
                harvestOnLoad = false;
                if(harvestInterval <= 0) {
                    System.out.println("ERROR CANNOT HAVE A HARVESTINTERVAL LESS THAN 1; DEFAULTING TO 2");
                    harvestInterval = 2;
                }
            }
            System.out.println("in init of harvestDaemon and starting thread.");
            
            scheduleTimer.scheduleAtFixedRate(new HarvestTimer("HarvestNow"),
                         harvestInterval*3600*1000,
                         harvestInterval*3600*1000);          
            //Thread myThread = new Thread(this);
            //myThread.start();
         }else {
             System.out.println("harvest not enabled.");
             //if harvest is not enabled then just leave.
             return;
         }//else
        
     }
     
  
     public void doGet(HttpServletRequest req, HttpServletResponse res)
                 throws IOException, ServletException
    {
 	  String nowParam = req.getParameter("HarvestNow");
      if(timer != null) {
          //hmmm just in case the servlet container decides to re-initialize
          //this servlet.
          timer.cancel();
          timer = null;
      }
      timer = new Timer();
      
 	  if( nowParam != null && !harvestStarted ) {
         //start the harvest in 5 seconds
         timer.schedule(new HarvestTimer("HarvestNow"),5000);
         harvestStarted = true;
       }
      String replicate = req.getParameter("ReplicateNow");
       if( replicate != null && !harvestStarted ) {
          //start a replication in 5 seconds
          timer.schedule(new HarvestTimer("ReplicateNow"),5000);
          harvestStarted = true;         
        }
       
       
       ServletOutputStream out = res.getOutputStream();
       res.setContentType("text/html");
       out.println("<html><head><title>Astrogrid Registry Harvest</title></head>");
       out.println("<body><a href=\"http://www.astrogrid.org\">");
       out.println("<img src=\"http://www.astrogrid.org/image/AGlogo\"" +
                   "align=right alt=\"AG logo\"> </a>");
       out.println("<h1>Astrogrid Registry Harvest Control Servlet</h1>" +
                   "<br><h2>Servlet initialized " + servletInitTime +
                   "<br>Harvest interval = " + harvestInterval + " hours" +
                   "<br>Number of Harvests initiated = " + myCounter +
                   "<br>Last harvest time = " + lastHarvestTime +
                   "<form method=\"get\"><input type=\"submit\" " +
                   " name=\"HarvestNow\" value=\"Harvest now!\">" +
                   "<br /><strong>Replication can be dangerous replicates all resources not by date</strong><br />" +
                   "<input type=\"submit\" name=\"ReplicateNow\" value=\"Replicate Now\" /></form>");
                   if(harvestStarted) {
                       out.println("<br /><i>A Harvest/Replicate has began or still running.</i>");
                   }
                   out.println("</h2></body></html>");
    }
 
    class HarvestTimer extends TimerTask {
        private String task = null;
        
        public HarvestTimer(String harvestTask) {
            task = harvestTask;
        }
        
        public void run() {
 
            try {
                if("HarvestNow".equals(task)) {
                    System.out.println("Immediate harvesting will be commenced!");
                    try {
                        rhs.harvestAll(true,true);
                    }catch(RegistryException e) {
                         e.printStackTrace();
                    }
                }
                if("ReplicateNow".equals(task)) {
                    System.out.println("Immediate replicate is beginning!");
                    try {
                       rhs.harvestAll(true,false);
                    }catch(RegistryException e) {
                       e.printStackTrace();
                    }
                }//if
            } finally {
                //turn off
                HarvestDaemon.harvestStarted = false;
            }
        }//run       
    }
 
    
    
 }