// Copyright Yahoo. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
package com.yahoo.search.grouping.request;

import java.util.Arrays;

/**
 * This class represents a day-of-year timestamp-function in a {@link GroupingExpression}. It evaluates to a long that
 * equals the day of year (0-365) of the result of the argument.
 *
 * @author Simon Thoresen Hult
 * @author bratseth
 */
public class DayOfYearFunction extends FunctionNode {

    /**
     * Constructs a new instance of this class.
     *
     * @param exp The expression to evaluate, must evaluate to a long.
     */
    public DayOfYearFunction(GroupingExpression exp) {
        this(null, null, exp);
    }

    private DayOfYearFunction(String label, Integer level, GroupingExpression exp) {
        super("time.dayofyear", label, level, Arrays.asList(exp));
    }

    @Override
    public DayOfYearFunction copy() {
        return new DayOfYearFunction(getLabel(),
                                     getLevelOrNull(),
                                     getArg(0).copy());
    }

}