/*$Id: DatacenterApplication.java,v 1.2 2005/03/21 18:45:55 mch Exp $
    * Created on 12-Jul-2004
    *
    * Copyright (C) AstroGrid. All rights reserved.
    *
    * This software is published under the terms of the AstroGrid
    * Software License version 1.2, a copy of which has been included
    * with this distribution in the LICENSE.txt file.
    *
   **/
  package org.astrogrid.dataservice.service.cea;
  
  import EDU.oswego.cs.dl.util.concurrent.Executor;
  import java.io.IOException;
  import java.io.StringWriter;
  import java.net.URISyntaxException;
  import java.security.Principal;
  import javax.xml.parsers.ParserConfigurationException;
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.astrogrid.account.LoginAccount;
  import org.astrogrid.applications.AbstractApplication;
  import org.astrogrid.applications.CeaException;
  import org.astrogrid.applications.Status;
  import org.astrogrid.applications.beans.v1.parameters.ParameterValue;
  import org.astrogrid.applications.description.ApplicationInterface;
  import org.astrogrid.applications.parameter.protocol.ProtocolLibrary;
  import org.astrogrid.dataservice.queriers.Querier;
  import org.astrogrid.dataservice.queriers.QuerierListener;
  import org.astrogrid.dataservice.queriers.status.QuerierStatus;
  import org.astrogrid.dataservice.service.AxisDataServer;
  import org.astrogrid.dataservice.service.DataServer;
  import org.astrogrid.query.Query;
  import org.astrogrid.query.QueryState;
  import org.astrogrid.query.SimpleQueryMaker;
  import org.astrogrid.query.adql.AdqlQueryMaker;
  import org.astrogrid.slinger.mime.MimeNames;
  import org.astrogrid.slinger.targets.TargetIdentifier;
  import org.astrogrid.slinger.targets.TargetMaker;
  import org.astrogrid.slinger.targets.WriterTarget;
  import org.astrogrid.slinger.vospace.HomespaceName;
  import org.astrogrid.slinger.vospace.IVOSRN;
  import org.astrogrid.workflow.beans.v1.Tool;
  import org.xml.sax.SAXException;
  
  /*** Represents a query running against the datacenter.
   * <p />
   * Datacenter already has a framework for starting asynchronous queries and then monitoring their progress.
   * This class wraps the datacenter framework, mapping querier events into events in the CEA framework.
   *
   * There is one instance of this class for each query
   *
   * @author Noel Winstanley nw@jb.man.ac.uk 12-Jul-2004
   *
   */
  public class DatacenterApplication extends AbstractApplication implements QuerierListener {
     
     /***
      * Commons Logger for this class
      */
     private static final Log logger = LogFactory.getLog(DatacenterApplication.class);
     
     protected final Principal acc;
     /*** the datacenter system object - a static, which provides access to the datacenter query framework */
     protected final DataServer serv;
     /*** the executor for background tasks */
     Executor exec;
     
     /*** id allocated by datacenter to this querier */
     protected String querierID;
     
     public String getQuerierId() { return querierID;   }
     
     /*** Construct a new DatacetnerApplication
      * @param arg0
      * @param arg1
      * @param arg2
      * @param arg3
      */
     public DatacenterApplication(IDs ids, Tool tool, ApplicationInterface interf, ProtocolLibrary arg3,DataServer serv,Executor exec) {
        super(ids, tool,interf, arg3);
        this.serv = serv;
        this.exec = exec;
        this.acc = new LoginAccount(ids.getUser().getUserId(),ids.getUser().getCommunity());
        logger.info("CEA DSA initialised, Job ID="+ids.getJobStepId());
     }
     
     /*** construct a query from the contents of the tool
      * (mch) not entirely happy with this following changes to Query that include
      * the result spec.  I've set it to table here and hope that targets etc get
      * set properly later (as it would have done before)
      * @param t
      * @return
      */
     protected final Query buildQuery(ApplicationInterface interf)  throws IOException, CeaException {
  
        if (interf.getName().equals(DatacenterApplicationDescription.CONE_IFACE)) {
           return SimpleQueryMaker.makeConeQuery(
              Double.parseDouble((String)findInputParameterAdapter(DatacenterApplicationDescription.RA).process())
                , Double.parseDouble((String)findInputParameterAdapter(DatacenterApplicationDescription.DEC).process())
                , Double.parseDouble((String)findInputParameterAdapter(DatacenterApplicationDescription.RADIUS).process())
          );
       }
       else if (interf.getName().equals(DatacenterApplicationDescription.ADQL_IFACE)) {
          String querySource = findInputParameter(DatacenterApplicationDescription.QUERY).getValue();
          String queryString = (String)findInputParameterAdapter(DatacenterApplicationDescription.QUERY).process();
          if ((queryString == null) || (queryString.trim().length() == 0)) {
             throw new IOException("Read empty string at "+querySource);
          }
          logger.debug("Query will be " + queryString);
          try {
             return AdqlQueryMaker.makeQuery(queryString);
          }
          catch (SAXException e) {
             throw new IllegalArgumentException(e+", reading Adql at "+querySource);
          }
       }
       else
       {
          // shouldn't get here - as would have barfed during 'initializeApplication' in DatacenterApplicatonDescription
          logger.fatal("Programming logic error - unknown interface" + interf.getName());
          throw new IllegalArgumentException("Programming logic error - unknown interface" + interf.getName());
       }
       
    }
    
    
    /***
     * @see org.astrogrid.applications.Application#execute()
     */
    public boolean execute() throws CeaException {
       createAdapters();
       try {
          ParameterValue resultTarget = findOutputParameter(DatacenterApplicationDescription.RESULT);
          TargetIdentifier ti = null;
          if (resultTarget.getIndirect()==true) {
             //results will go to the URI given in the parameter
             if ((resultTarget.getValue() == null) || (resultTarget.getValue().trim().length() == 0)) {
                throw new CeaException("ResultTarget is indirect but value is empty");
             }
             
             String targetUri = transformTarget(resultTarget.getValue()); //special botch for old vs new homespaces etc
             
             ti = TargetMaker.makeTarget(targetUri);
          } else {
             //direct-to-cea target, so results must get written to a string to be inserted into the
             //parametervalue when complete (see queryStatusChanged)
             ti = TargetMaker.makeTarget(new StringWriter(), true); //close stream when finished writing to it
          }
 
          String resultsFormat = MimeNames.getMimeType( findInputParameterAdapter(DatacenterApplicationDescription.FORMAT).process().toString());
          
          Query query = buildQuery(getApplicationInterface());
          query.getResultsDef().setTarget(ti);
          query.getResultsDef().setFormat(resultsFormat);
          Querier querier = Querier.makeQuerier(acc,query, "CEA from "+AxisDataServer.getSource()+" [Job "+ids.getJobStepId()+"]");
          querier.addListener(this);
          
          setStatus(Status.INITIALIZED);
          querierID = serv.submitQuerier(querier);
          logger.info("assigned QuerierID " + querierID);
          return true;
       }
       catch (Throwable e) {
          reportError(e+" executing "+this.getTool().getName(),e);
          if (e instanceof CeaException) {
             throw (CeaException) e;
          }
          else {
             throw new CeaException(e+", executing application "+this.getTool().getName(),e);
          }
       }
    }
 
    /***
     * If the incoming URI describing the target location is an IVORN, it might be
     * an account or it might be a real IVORN.  Examines it to see if it is of the
     * form of an account (ie ivo://community/individual) and if so, checks to see
     * if the Registry can resolve it.  If it is of the right form, and the registry
     * cannot resolve it, turns it into a homespacename
     */
    public String transformTarget(String targetUri) throws IllegalArgumentException, URISyntaxException {
       if (!IVOSRN.isIvorn(targetUri)) { return targetUri; } //some other URI
 
       int hashIdx = targetUri.indexOf("#");
       if (hashIdx == -1) {
          throw new IllegalArgumentException("Target URI "+targetUri+" has no path given");
       }
       String key = targetUri.substring(0,hashIdx).substring(6);
       int slashIdx = key.indexOf("/");
       if ((slashIdx != -1) && (slashIdx == key.lastIndexOf("/"))) { //if there is only one slash
          
          //check it can't be resolved
          try {
             new IVOSRN(targetUri).resolve();
             //it resolved OK, so it's a real IVORN.  Leave unchanged
             return targetUri;
          }
          catch (IOException rre) { } //carry on, it's not resolvable (normally), so...
          
          //assume any exception means it can't be found.  Can't do much better than that at the mo anyway
          String ind = key.substring(slashIdx+1); //individual
          String com = key.substring(0,slashIdx); //community
          HomespaceName homespace = new HomespaceName(ind+"@"+com, targetUri.substring(hashIdx+1));
          logger.info("Converting incoming '"+targetUri+"' to '"+homespace+"'");
          return homespace.toURI();
       }
       return targetUri;
    }
          
    /*** Implemented by calling abot on the querier object - so if the underlyng database back end supports abort, the cec does too
     * @see org.astrogrid.applications.Application#attemptAbort()
     */
    public boolean attemptAbort() {
       try {
          QuerierStatus stat = serv.abortQuery(acc,querierID);
          if (stat.getState().equals(QueryState.ABORTED)) {
             return true;
          } else {
             return false; // assume this means we couldn't abort.
          }
       } catch (IOException e) {
          logger.warn("Attempted abort failed with exception",e);
          return false;
       }
    }
    
    
    /*** callback method for our associated querier
     * <p />Through this method, this class receives notifications in changes of state of the running query.
     * These state changes and messages are propagated onto the cea framework,
     * and results are grabbed from the query at the appropriate time.
     * @see org.astrogrid.datacenter.queriers.QuerierListener#queryStatusChanged(org.astrogrid.datacenter.queriers.Querier)
     */
    public void queryStatusChanged(final Querier querier) {
       QuerierStatus qs = querier.getStatus();
       QueryState state = qs.getState();
       logger.debug("CEA seen DSA state="+state);
       // would be nice to use a switch here, but can't.
       if (state.equals(QueryState.CONSTRUCTED) || state.equals(QueryState.QUEUED)) {
          this.setStatus(Status.INITIALIZED);
          
       } else if (state.equals(QueryState.STARTING) || state.equals(QueryState.RUNNING_QUERY)) {
          this.setStatus(Status.RUNNING);
          
       } else if (state.equals(QueryState.QUERY_COMPLETE)) {
          this.reportMessage(qs.toString());
          
       } else if (state.equals(QueryState.RUNNING_RESULTS)) {
          this.setStatus(Status.WRITINGBACK);
          /* this is all handled by the target indicators and the 'finish' below
           final ParameterAdapter result = (ParameterAdapter)outputParameterAdapters().next();
           //necessary to perform write-back in separate thread - as we don't know what thread is calling this callback
           // and it mustn't be the same one as is going to write out the output - otherwise we'll deadlock on the pipe.
           Runnable worker = new Runnable() {
           public void run() {
           try {
           CEATargetIndicator ti = (CEATargetIndicator)querier.getQuery().getTarget();
           result.writeBack(ti);
           setStatus(Status.COMPLETED); // now the application has completed..
           } catch (CeaException e) {
           reportError("Failed to write back parameter values",e);
           }
           }
           };
           try {
           exec.execute(worker);
           }catch (InterruptedException e) {
           reportMessage("couldn't start worker thread to read results");
           }
           */
       } else if (state.equals(QueryState.ABORTED)) {
          this.reportMessage(qs.toString());
          this.setStatus(Status.ERROR); // this is the convention.
          
       } else if (state.equals(QueryState.ERROR)) {
          this.reportError(qs.toString()); // sets us in error state.
          
       } else if (state.equals(QueryState.FINISHED)) {
          ParameterValue result = findOutputParameter(DatacenterApplicationDescription.RESULT);
          if (result.getIndirect() != true) {
             //if the results were to be directed to CEA, they will be stored in a StringWriter in
             //the WriterTarget
             WriterTarget target = (WriterTarget) querier.getQuery().getTarget();
             StringWriter sw = (StringWriter) target.resolveWriter(acc);
             result.setValue(sw.toString() );
          }
 
          this.setStatus(Status.COMPLETED);
          this.reportMessage(qs.toString());
          
       } else if (state.equals(QueryState.UNKNOWN)) {
          this.setStatus(Status.UNKNOWN);
          this.reportMessage(qs.toString());
          
       } else {
          logger.fatal("Programming error - unknown state encountered" + state.toString());
          // would like to throw, but won't - as don't know who called me.
          this.setStatus(Status.UNKNOWN);
          this.reportMessage("Unkown state encountered " + state.toString());
       }
       
    }
    
    
    /*** overridden, to return instances of datacenter parameter adapter.
     * @see org.astrogrid.applications.AbstractApplication#instantiateAdapter(org.astrogrid.applications.beans.v1.parameters.ParameterValue, org.astrogrid.applications.description.ParameterDescription, org.astrogrid.applications.parameter.indirect.IndirectParameterValue)
     *
    protected ParameterAdapter instantiateAdapter(ParameterValue arg0,
                                                  ParameterDescription arg1, ExternalValue arg2) {
       return new DatacenterParameterAdapter(arg0, arg1, arg2);
    }
     */
 }
 
 
 /*
  $Log: DatacenterApplication.java,v $
  Revision 1.2  2005/03/21 18:45:55  mch
  Naughty big lump of changes
 
  Revision 1.1.1.1  2005/02/17 18:37:35  mch
  Initial checkin
 
  Revision 1.1.1.1  2005/02/16 17:11:24  mch
  Initial checkin
 
  Revision 1.12.2.11  2005/02/11 15:58:27  mch
  Some fixes before split
 
  Revision 1.12.2.10  2004/12/08 18:36:40  mch
  Added Vizier, rationalised SqlWriters etc, separated out TableResults from QueryResults
 
  Revision 1.12.2.9  2004/12/07 21:21:09  mch
  Fixes after a days integration testing
 
  Revision 1.12.2.8  2004/12/07 00:02:17  mch
  added tentative ivorn->homespace converter
 
  Revision 1.12.2.7  2004/11/30 01:04:02  mch
  Rationalised tablewriters, reverted AxisDataService06 to string
 
  Revision 1.12.2.6  2004/11/29 21:52:18  mch
  Fixes to skynode, log.error(), getstem, status logger, etc following tests on grendel
 
  Revision 1.12.2.5  2004/11/25 08:29:41  mch
  added table writers modelled on STIL
 
  Revision 1.12.2.4  2004/11/23 17:46:52  mch
  Fixes etc
 
  Revision 1.12.2.3  2004/11/23 12:34:01  mch
  renamed to makeTarget
 
  Revision 1.12.2.2  2004/11/23 11:55:06  mch
  renamved makeTarget methods
 
  Revision 1.12.2.1  2004/11/22 00:57:16  mch
  New interfaces for SIAP etc and new slinger package
 
  Revision 1.12  2004/11/11 20:42:50  mch
  Fixes to Vizier plugin, introduced SkyNode, started SssImagePlugin
 
  Revision 1.11  2004/11/10 22:01:50  mch
  skynode starts and some fixes
 
  Revision 1.10  2004/11/09 17:42:22  mch
  Fixes to tests after fixes for demos, incl adding closable to targetIndicators
 
  Revision 1.9  2004/11/08 02:58:44  mch
  Various fixes and better error messages
 
  Revision 1.8  2004/11/03 00:17:56  mch
  PAL_MCH Candidate 2 merge
 
  Revision 1.3.8.4  2004/11/02 21:51:54  mch
  Replaced AgslTarget with UrlTarget and MySpaceTarget
 
  Revision 1.3.8.3  2004/11/02 19:48:43  mch
  Split TargetIndicator to indicator and maker
 
  Revision 1.3.8.2  2004/11/02 19:41:26  mch
  Split TargetIndicator to indicator and maker
 
  Revision 1.3.8.1  2004/10/20 18:12:45  mch
  CEA fixes, resource tests and fixes, minor navigation changes
 
  Revision 1.4.2.1  2004/10/20 12:43:28  mch
  Fixes to CEA interface to write directly to target
 
  Revision 1.4  2004/10/20 08:10:55  pah
  taken Principal of new backend phase and tidied up some logging
 
  Revision 1.3  2004/10/07 10:34:44  mch
  Fixes to Cone maker functions and reading/writing String comparisons from Query
 
  Revision 1.2  2004/10/06 21:12:17  mch
  Big Lump of changes to pass Query OM around instead of Query subclasses, and TargetIndicator mixed into Slinger
 
  Revision 1.1  2004/09/28 15:02:13  mch
  Merged PAL and server packages
 
  Revision 1.8  2004/09/17 01:27:21  nw
  added thread management.
 
  Revision 1.7  2004/09/06 15:20:47  mch
  Added logger message for execute()
 
  Revision 1.6  2004/08/25 23:38:34  mch
  (Days changes) moved many query- and results- related classes, renamed packages, added tests, added CIRCLE to sql/adql parsers
 
  Revision 1.5  2004/08/17 20:19:36  mch
  Moved TargetIndicator to client
 
  Revision 1.4  2004/07/27 13:48:33  nw
  renamed indirect package to protocol,
  renamed classes and methods within protocol package
 
  Revision 1.3  2004/07/22 16:31:22  nw
  cleaned up application / parameter adapter interface.
 
  Revision 1.2  2004/07/20 02:14:48  nw
  final implementaiton of itn06 Datacenter CEA interface
 
  Revision 1.1  2004/07/13 17:11:09  nw
  first draft of an itn06 CEA implementation for datacenter
  
  */