/**************************************************************************
 * AgentProxy.java
 *
 * $Revision: 1.37 $
 * $Date: 2005/10/05 07:39:36 $
 *
 * Copyright (C) 2001 CERN - European Organization for Nuclear Research
 * All rights reserved.
 **************************************************************************/

package com.c2kernel.entity.proxy;

import java.util.Date;
import java.util.Enumeration;

import com.c2kernel.common.AccessRightsException;
import com.c2kernel.common.InvalidDataException;
import com.c2kernel.common.InvalidTransitionException;
import com.c2kernel.common.ObjectAlreadyExistsException;
import com.c2kernel.common.ObjectNotFoundException;
import com.c2kernel.common.PersistencyException;
import com.c2kernel.entity.Agent;
import com.c2kernel.entity.AgentHelper;
import com.c2kernel.entity.C2KLocalObject;
import com.c2kernel.entity.ManageableEntity;
import com.c2kernel.entity.agent.Job;
import com.c2kernel.lifecycle.instance.predefined.PredefinedStep;
import com.c2kernel.lifecycle.instance.stateMachine.Transitions;
import com.c2kernel.lookup.AgentPath;
import com.c2kernel.lookup.DomainPath;
import com.c2kernel.lookup.EntityPath;
import com.c2kernel.lookup.InvalidEntityPathException;
import com.c2kernel.lookup.Path;
import com.c2kernel.persistency.outcome.OutcomeValidator;
import com.c2kernel.persistency.outcome.Schema;
import com.c2kernel.process.Gateway;
import com.c2kernel.scripting.ErrorInfo;
import com.c2kernel.scripting.Script;
import com.c2kernel.scripting.ScriptErrorException;
import com.c2kernel.scripting.ScriptingEngineException;
import com.c2kernel.utils.LocalObjectLoader;
import com.c2kernel.utils.Logger;

/******************************************************************************
 * It is a wrapper for the connection and communication with Agent
 * It caches data loaded from the Agent to reduce communication
 *
 * @version $Revision: 1.37 $ $Date: 2005/10/05 07:39:36 $
 * @author  $Author: abranson $
 ******************************************************************************/
public class AgentProxy extends EntityProxy
{
    AgentPath path;

   /**************************************************************************
    * Creates an AgentProxy without cache and change notification
    **************************************************************************/
    public AgentProxy( org.omg.CORBA.Object  ior,
                          int               systemKey)
        throws ObjectNotFoundException
    {
        super(ior, systemKey);
        try {
            path = new AgentPath(systemKey);
        } catch (InvalidEntityPathException e) {
            throw new ObjectNotFoundException();
        }
    }

    @Override
	public ManageableEntity narrow() throws ObjectNotFoundException
    {
        try {
            return AgentHelper.narrow(mIOR);
        } catch (org.omg.CORBA.BAD_PARAM ex) { }
        throw new ObjectNotFoundException("CORBA Object was not an Agent, or the server is down.");
    }
   /**************************************************************************
    *
    *
    **************************************************************************/
    public void initialise( String  agentProps, String collector )
        throws AccessRightsException,
               InvalidDataException,
               PersistencyException,
               ObjectNotFoundException
    {
        Logger.msg(7, "AgentProxy::initialise - started");

        ((Agent)getEntity()).initialise( agentProps );
    }

    public AgentPath getPath() {
        return path;
    }

    /**
     * Executes a job on the given item using this agent.
     *
     * @param item - item holding this job
     * @param job - the job to execute
     * @throws ScriptErrorException 
     */
    public void execute(ItemProxy item, Job job)
        throws AccessRightsException,
        InvalidTransitionException,
        ObjectNotFoundException,
        InvalidDataException,
        PersistencyException,
        ObjectAlreadyExistsException,
        ScriptErrorException
    {
        OutcomeValidator validator = null;
        String scriptName = job.getActPropString("ScriptName");
        Date startTime = new Date();
        Logger.msg(3, "AgentProxy - executing "+job.getStepPath()+" for "+path.getAgentName());
        // get the outcome validator if present
        if (job.isOutcomeSet())
        {
        	String schemaName = job.getSchemaType();
        	int schemaVersion = job.getSchemaVersion();

            Logger.msg(5, "AgentProxy - fetching schema "+schemaName+"_"+schemaVersion+" for validation");
            // retrieve schema
            Schema schema = LocalObjectLoader.getSchema(schemaName, schemaVersion);

            if (schema == null)
                throw new InvalidDataException("Job references outcome type "+schemaName+" version "+schemaVersion+" that does not exist in this centre.", "");

            try {
                validator = OutcomeValidator.getValidator(schema);
            } catch (Exception e) {
                throw new InvalidDataException("Could not create validator: "+e.getMessage(), "");
            }
        }

        if(scriptName != null && scriptName.length() > 0 &&
            (job.getPossibleTransition() == Transitions.DONE || job.getPossibleTransition() == Transitions.COMPLETE)) {
            Logger.msg(3, "AgentProxy - executing script "+scriptName);
            try {

                // pre-validate outcome from script if there is one
                if (job.getOutcomeString()!= null && validator != null) {
                    Logger.msg(5, "AgentProxy - validating outcome before script execution");
                    String error = validator.validate(job.getOutcomeString());
                    if (error.length() > 0) {
                        Logger.error("Outcome not valid: \n " + error);
                        throw new InvalidDataException(error, "");
                    }
                }

                // load script
                ErrorInfo scriptErrors = (ErrorInfo)callScript(item, job);

                String errorString = scriptErrors.toString();
                if (scriptErrors.getFatal()) {
                    Logger.msg(3, "AgentProxy - fatal script error");
                    throw new ScriptErrorException(scriptErrors);
                }
                if (errorString.length() > 0)
                    Logger.warning("Script errors: "+errorString);
            } catch (ScriptingEngineException ex) {
                Logger.error(ex);
                throw new InvalidDataException(ex.getMessage(), "");
            }
        }

        if (job.isOutcomeSet()) {
            Logger.msg(3, "AgentProxy - validating outcome");
            String error = validator.validate(job.getOutcomeString());
            if (error.length() > 0)
                throw new InvalidDataException(error, "");
        }

        job.setAgentId(getSystemKey());
        Logger.msg(3, "AgentProxy - submitting job to item proxy");
        item.requestAction(job);
        if (Logger.doLog(3)) {
            Date timeNow = new Date();
        	long secsNow = (timeNow.getTime()-startTime.getTime())/1000;
        	Logger.msg(3, "Execution took "+secsNow+" seconds");
        }
    }

    private Object callScript(ItemProxy item, Job job) throws ScriptingEngineException {
    	Script script = new Script(item, this, job);
    	return script.execute();
    }

    /**
     * Standard execution of jobs. Note that this method should always be the one used from clients - all execution
     * parameters are taken from the job where they're probably going to be correct.
     *
     * @param job
     * @throws AccessRightsException
     * @throws InvalidDataException
     * @throws InvalidTransitionException
     * @throws ObjectNotFoundException
     * @throws PersistencyException
     * @throws ObjectAlreadyExistsException
     * @throws ScriptErrorException 
     */
    public void execute(Job job)
        throws AccessRightsException,
               InvalidDataException,
               InvalidTransitionException,
               ObjectNotFoundException,
               PersistencyException,
               ObjectAlreadyExistsException, 
               ScriptErrorException
    {
        try {
            ItemProxy targetItem = (ItemProxy)Gateway.getProxyManager().getProxy(new EntityPath(job.getItemSysKey()));
            execute(targetItem, job);
        } catch (InvalidEntityPathException e) {
            throw new ObjectNotFoundException("Job contained invalid item sysKey: "+job.getItemSysKey(), "");
        }
    }

    public void execute(ItemProxy item, String predefStep, C2KLocalObject obj)
    throws AccessRightsException,
           InvalidDataException,
           InvalidTransitionException,
           ObjectNotFoundException,
           PersistencyException,
           ObjectAlreadyExistsException
    {
        String param;
        try {
            param = marshall(obj);
        } catch (Exception ex) {
            Logger.error(ex);
            throw new InvalidDataException("Error on marshall", "");
        }
        execute(item, predefStep, param);
    }

    public void execute(ItemProxy item, String predefStep, String... params)
    throws AccessRightsException,
           InvalidDataException,
           InvalidTransitionException,
           ObjectNotFoundException,
           PersistencyException,
           ObjectAlreadyExistsException
    {
        item.requestAction(getSystemKey(), "workflow/predefined/"+predefStep, Transitions.DONE, PredefinedStep.bundleData(params));
    }

    /** Wrappers for scripts */
    public String marshall(Object obj) throws Exception {
        return Gateway.getMarshaller().marshall(obj);
    }

    public Object unmarshall(String obj) throws Exception {
        return Gateway.getMarshaller().unmarshall(obj);
    }

    /** Let scripts resolve items */
    public ItemProxy searchItem(String name) throws ObjectNotFoundException {
        Enumeration<Path> results = Gateway.getLookup().search(new DomainPath(""),name);

        Path returnPath = null;
        if (!results.hasMoreElements())
            throw new ObjectNotFoundException(name, "");

        while(results.hasMoreElements()) {
            Path nextMatch = results.nextElement();
            if (returnPath != null && nextMatch.getSysKey() != -1 && returnPath.getSysKey() != nextMatch.getSysKey())
                throw new ObjectNotFoundException("Too many items with that name");
            returnPath = nextMatch;
        }

        return (ItemProxy)Gateway.getProxyManager().getProxy(returnPath);
    }

    public ItemProxy getItem(String itemPath) throws ObjectNotFoundException {
    	return (getItem(new DomainPath(itemPath)));
    }

    public ItemProxy getItem(Path itemPath) throws ObjectNotFoundException {
    	return (ItemProxy)Gateway.getProxyManager().getProxy(itemPath);
    }

    public ItemProxy getItemBySysKey(int sysKey) throws ObjectNotFoundException, InvalidEntityPathException {
        return (ItemProxy)Gateway.getProxyManager().getProxy(new EntityPath(sysKey));
    }
}