/*******************************************************************************
 * Copyright (c) 1998, 2013 Oracle and/or its affiliates. All rights reserved.
 * This program and the accompanying materials are made available under the 
 * terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0 
 * which accompanies this distribution. 
 * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
 * and the Eclipse Distribution License is available at 
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * Contributors:
 *     Oracle - initial API and implementation from Oracle TopLink
 ******************************************************************************/  
package org.eclipse.persistence.internal.jpa.parsing;

import org.eclipse.persistence.expressions.Expression;
import org.eclipse.persistence.internal.expressions.DateConstantExpression;

/**
 * INTERNAL
 * <p><b>Purpose</b>: Represent a Date, Time or TimeStamp literal
 * <p><b>Responsibilities</b>:<ul>
 * <li> Generate the correct expression for the temporal expression
 * </ul>
 */
public class TemporalLiteralNode extends LiteralNode {
    
    public enum TemporalType {DATE, TIME, TIMESTAMP}
    
    private TemporalType type;
    
    /**
     * Return a new StringLiteralNode
     */
    public TemporalLiteralNode(TemporalType type) {
        super();
        this.type = type;
    }

    /**
     * Return a new StringLiteralNode with the internal string set to the
     * passed value
     */
    public TemporalLiteralNode(String theString, TemporalType type) {
        this(type);
        setLiteral(theString);
    }

    /**
     * INTERNAL
     * Generate the a new EclipseLink ConstantExpression for this node.
     */
    public Expression generateExpression(GenerationContext context) {
        DateConstantExpression whereClause = new DateConstantExpression(literal, context.getBaseExpression());
        return whereClause;
    }
    
    /**
     * INTERNAL
     * Validate node and calculate its type.
     */
    public void validate(ParseTreeContext context) {
        TypeHelper typeHelper = context.getTypeHelper();
        if (type == TemporalType.DATE){
            setType(typeHelper.getSQLDateType());
        } else if (type == TemporalType.TIME) {
            setType(typeHelper.getTimeType());
        } else if (type == TemporalType.TIMESTAMP){
            setType(typeHelper.getTimestampType());
        }
    }
}