/*
 ***************************************************************************************
 *  Copyright (C) 2006 EsperTech, Inc. All rights reserved.                            *
 *  http://www.espertech.com/esper                                                     *
 *  http://www.espertech.com                                                           *
 *  ---------------------------------------------------------------------------------- *
 *  The software in this package is published under the terms of the GPL license       *
 *  a copy of which has been included with this distribution in the license.txt file.  *
 ***************************************************************************************
 */
package com.espertech.esper.epl.core.eval;

import com.espertech.esper.client.EventBean;
import com.espertech.esper.client.EventType;
import com.espertech.esper.epl.core.SelectExprProcessor;
import com.espertech.esper.epl.expression.core.ExprEvaluator;
import com.espertech.esper.epl.expression.core.ExprEvaluatorContext;
import com.espertech.esper.event.EventAdapterService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public abstract class EvalBaseFirstProp implements SelectExprProcessor {

    private static final Logger log = LoggerFactory.getLogger(EvalBaseFirstProp.class);

    private final SelectExprContext selectExprContext;
    private final EventType resultEventType;

    public EvalBaseFirstProp(SelectExprContext selectExprContext, EventType resultEventType) {
        this.selectExprContext = selectExprContext;
        this.resultEventType = resultEventType;
    }

    public abstract EventBean processFirstCol(Object result);

    public EventBean process(EventBean[] eventsPerStream, boolean isNewData, boolean isSynthesize, ExprEvaluatorContext exprEvaluatorContext) {
        ExprEvaluator[] expressionNodes = selectExprContext.getExpressionNodes();

        Object first = expressionNodes[0].evaluate(eventsPerStream, isNewData, exprEvaluatorContext);
        return processFirstCol(first);
    }

    public EventAdapterService getEventAdapterService() {
        return selectExprContext.getEventAdapterService();
    }

    public EventType getResultEventType() {
        return resultEventType;
    }
}