/*
    * $Id: Monitor.java,v 1.1 2006/06/16 14:50:06 kea Exp $
    */
   
   package org.astrogrid.monitor;
   
   import java.io.IOException;
   import java.io.InputStream;
   import java.io.OutputStreamWriter;
  import java.io.PrintWriter;
  import java.net.MalformedURLException;
  import java.net.URL;
  import java.rmi.RemoteException;
  import java.util.Enumeration;
  import java.util.Vector;
  import javax.xml.rpc.ServiceException;
  import javax.xml.rpc.encoding.XMLType;
  import org.apache.axis.client.Call;
  import org.apache.axis.client.Service;
  import org.astrogrid.status.ServiceStatus;
  import org.astrogrid.util.TimeStamp;
  
  /***
   * Servlet for monitoring the statuses of other services and displaying them
   * in HTML
   *
   * @author mch
   */
  public class Monitor  {
  
     Vector datacenters = null;
     Vector ceaServices = null;
  
     final static String ERR_COLOUR = "#FF0000";
     final static String OK_COLOUR = "#00FF00";
     final static String WARN_COLOUR = "#FFFF00";
     
     /*** Set up with default list of datacenters */
     protected void initialise() {
        datacenters = new Vector();
        datacenters.add("http://grendel12.roe.ac.uk:8080/pal-6df");
        datacenters.add("http://grendel12.roe.ac.uk:8080/pal-sec");
        datacenters.add("http://grendel12.roe.ac.uk:8080/pal-vizier");
        datacenters.add("http://astrogrid.roe.ac.uk:8080/pal-ssa");
        datacenters.add("http://astrogrid.roe.ac.uk:8080/pal-usnob");
        datacenters.add("http://astrogrid.roe.ac.uk:8080/pal-twomass");
        datacenters.add("http://zhumulangma.star.le.ac.uk:8080/astrogrid-pal-SNAPSHOT");
        datacenters.add("http://msslxy.mssl.ucl.ac.uk:8080/astrogrid-pal-fits-SNAPSHOT");
        datacenters.add("http://ag01.ast.cam.ac.uk:8080/astrogrid-pal-Itn05_release");
        datacenters.add("http://twmbarlwm.star.le.ac.uk:8888/astrogrid-pal-SNAPSHOT");
        datacenters.add("http://twmbarlwm.star.le.ac.uk:8888/astrogrid-pal-fits-SNAPSHOT");
        datacenters.add("http://twmbarlwm.star.le.ac.uk:8888/astrogrid-pal-cds-SNAPSHOT");
        datacenters.add("http://twmbarlwm.star.le.ac.uk:8888/astrogrid-pal-sec-SNAPSHOT");
           
        ceaServices = new Vector();
        ceaServices.add("http://grendel12.roe.ac.uk:8080/pal-6df");
        ceaServices.add("http://grendel12.roe.ac.uk:8080/pal-sec");
        ceaServices.add("http://grendel12.roe.ac.uk:8080/pal-vizier");
        ceaServices.add("http://astrogrid.roe.ac.uk:8080/pal-ssa");
        ceaServices.add("http://astrogrid.roe.ac.uk:8080/pal-usnob");
        ceaServices.add("http://astrogrid.roe.ac.uk:8080/pal-twomass");
        ceaServices.add("http://zhumulangma.star.le.ac.uk:8080/astrogrid-pal-SNAPSHOT");
     }
     
     public Monitor() {
        initialise();
     }
     
     /***
      * Finds out statuses of all services and makes an Html table to the given
      * Writer.  Does it this way so we can flush as we write, in case some servers
      * timeout, etc
      */
     public void writeHtmlTables(PrintWriter out)  throws IOException {
  
        out.print("<h3>Datacenters</h3>");
        out.print("<table>"+
                     "<tr>"+
                     "<th>Endpoint</th><th>JSP</th><th>SOAP</th>"+
                     "</tr>");
        
        Enumeration datacenter = datacenters.elements();
        while (datacenter.hasMoreElements()) {
           out.flush();
           String endpoint = (String) datacenter.nextElement();
           writeDatacenterStatusRow(endpoint, out);
        }
        out.print("</table>");
        out.flush();
     }
     
     
     
     protected void writeDatacenterStatusRow(String endpoint, PrintWriter out) {
        out.println("<tr>");
        out.println("<td><a href='"+endpoint+"'>"+endpoint+"</a></td>");
        try {
           //test JSP connection
           TimeStamp timestamp = new TimeStamp();
          URL url = new URL(endpoint+"/serverStatus.jsp");
          InputStream in = url.openStream();
          String bgcolor=OK_COLOUR;
          if (timestamp.getSecsSince()>5) { bgcolor=WARN_COLOUR; }
          out.println("<td bgcolor='"+bgcolor+"'>"+timestamp.getSecsSince()+"s</td>");
       }
       catch (MalformedURLException mue) {
          out.println("<td bgcolor='"+ERR_COLOUR+"'>"+mue.getMessage()+"</td>");
       }
       catch (IOException ioe) {
          out.println("<td bgcolor='"+ERR_COLOUR+"'>"+ioe.getMessage()+"</td>");
       }
          
       //test SOAP connection
       try {
          TimeStamp timestamp = new TimeStamp();
          ServiceStatus status = getDatacenterStatus(endpoint);
          out.println("<td bgcolor='"+OK_COLOUR+"'>"+timestamp.getSecsSince()+"s</td>");
       }
       catch (ServiceException e) {
          out.println("<td bgcolor='"+ERR_COLOUR+"'>"+e+"</td>");
       }
       catch (RemoteException e) {
          out.println("<td bgcolor='"+ERR_COLOUR+"'>"+e+"</td>");
       }
          
       out.println("</tr>\n");
       
    }
    
    public static ServiceStatus getDatacenterStatus(String endpoint) throws ServiceException, RemoteException {
       Service  service = new Service();
       Call     call    = (Call) service.createCall();
       
       call.setTargetEndpointAddress( endpoint+"/services/AxisDataService06");
       call.setOperationName("getServiceStatus");
       
       //call.setReturnType( XMLType.XSD_STRING );
       
       Object response = call.invoke( new Object[] {  } );
       
       return null;
    }
    
    public static String getSimpleDatacenterStatus(String endpoint) throws ServiceException, RemoteException {
       Service  service = new Service();
       Call     call    = (Call) service.createCall();
       
       call.setTargetEndpointAddress( endpoint+"/services/AxisDataService06");
       call.setOperationName("getSimpleServiceStatus");
       
       call.setReturnType( XMLType.XSD_STRING );
       
       return (String) call.invoke( new Object[] {  } );
    }
    /*
    public String getCeaStatus(String endpoint) {
       Call call = getCall();
       SOAPBodyElement sbeRequest =
                                  new SOAPBodyElement();
       sbeRequest.setName("submitQuery");
       try {
          Vector result = (Vector) call.invoke (new Object[] {sbeRequest});
          SOAPBodyElement sbe = (SOAPBodyElement) result.get(0);
          Document resultDoc = sbe.getAsDocument();
       }catch(RemoteException re) {
          log.debug(re);
       } catch (Exception e) {
          resultDoc = null;
          e.printStackTrace();
          log.debug(e);
    }
 
    private Call getCall() {
       log.debug("entered getCall()");
       if(DEBUG_FLAG) log.info("entered getCall()");
       Call _call = null;
       try {
          Service  service = new Service();
          _call = (Call) service.createCall();
          _call.setTargetEndpointAddress(this.endPoint);
          _call.setSOAPActionURI("");
          _call.setOperationStyle(org.apache.axis.enum.Style.MESSAGE);
          _call.setOperationUse(org.apache.axis.enum.Use.LITERAL);
          _call.setEncodingStyle(null);
       } catch(ServiceException se) {
          se.printStackTrace();
          log.debug(se);
          _call = null;
       }finally {
          log.debug("exiting getCall()");
          if(DEBUG_FLAG) log.info("exiting getCall()");
          return _call;
       }
    }
     */
    
    /***
     *
     */
    public static void main(String[] args) throws IOException {
       Monitor m = new Monitor();
       PrintWriter out =new PrintWriter(new OutputStreamWriter(System.out));
       out.write("<html><body>");
       m.writeHtmlTables(out);
       out.write("</body></html>");
    }
 }