/**************************************************************************
 * AssignItemToSlot
 *
 * $Workfile$
 * $Revision: 1.8 $
 * $Date: 2004/10/21 08:02:19 $
 *
 * Copyright (C) 2001 CERN - European Organization for Nuclear Research
 * All rights reserved.
 **************************************************************************/

package com.c2kernel.lifecycle.instance.predefined;


import java.util.Arrays;

import com.c2kernel.collection.Aggregation;
import com.c2kernel.collection.AggregationMember;
import com.c2kernel.common.InvalidDataException;
import com.c2kernel.common.ObjectNotFoundException;
import com.c2kernel.lookup.AgentPath;
import com.c2kernel.lookup.ItemPath;
import com.c2kernel.persistency.ClusterStorage;
import com.c2kernel.persistency.ClusterStorageException;
import com.c2kernel.process.Gateway;
import com.c2kernel.utils.Logger;

/**************************************************************************
 *
 * @author $Author: abranson $ $Date: 2004/10/21 08:02:19 $
 * @version $Revision: 1.8 $
 **************************************************************************/
public class ClearSlot extends PredefinedStep
{
    /**************************************************************************
    * Constructor for Castor
    **************************************************************************/
    public ClearSlot()
    {
        super();
    }


    /**
     * Params:
     * 0 - collection name
     * 1 - slot number
     */
    @Override
	protected String runActivityLogic(AgentPath agent, ItemPath item,
			int transitionID, String requestData) throws InvalidDataException {
    	
        String collName;
        int slotNo;
        Aggregation agg;

        // extract parameters
        String[] params = getDataList(requestData);
        if (Logger.doLog(3)) Logger.msg(3, "ClearSlot: called by "+agent+" on "+item+" with parameters "+Arrays.toString(params));

        try {
            collName = params[0];
            slotNo = Integer.parseInt(params[1]);
        } catch (Exception e) {
            throw new InvalidDataException("ClearSlot: Invalid parameters "+Arrays.toString(params), "");
        }

        // load collection
        try {
            agg = (Aggregation)Gateway.getStorage().get(item, ClusterStorage.COLLECTION+"/"+collName+"/last", null);
		} catch (ObjectNotFoundException ex) {
			throw new InvalidDataException("ClearSlot: Collection '"+collName+"' not found in this Item", "");
		} catch (ClusterStorageException ex) {
			Logger.error(ex);
			throw new InvalidDataException("ClearSlot: Error loading collection '"+collName+"': "+ex.getMessage(), "");
		}

        // find member and clear
        boolean stored = false;
        for (AggregationMember member : agg.getMembers().list) {
            if (member.getID() == slotNo) {
                if (member.getItemPath() != null)
                    throw new InvalidDataException("ClearSlot: Member slot "+slotNo+" already empty", "");
                member.clearItem();
                stored = true;
                break;
            }
        }
        if (!stored) {
            throw new InvalidDataException("Member slot "+slotNo+" not found.", "");
        }


		try {
            Gateway.getStorage().put(item, agg, null);
        } catch (ClusterStorageException e) {
            Logger.error(e);
            throw new InvalidDataException("Error storing collection", "");
        }
        return requestData;
    }
}