/* ====================================================================
   Licensed to the Apache Software Foundation (ASF) under one or more
   contributor license agreements.  See the NOTICE file distributed with
   this work for additional information regarding copyright ownership.
   The ASF licenses this file to You under the Apache License, Version 2.0
   (the "License"); you may not use this file except in compliance with
   the License.  You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
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package org.apache.poi.ss.formula.functions;

import org.apache.poi.ss.formula.eval.ErrorEval;
import org.apache.poi.ss.formula.eval.EvaluationException;
import org.apache.poi.ss.formula.eval.OperandResolver;
import org.apache.poi.ss.formula.eval.StringEval;
import org.apache.poi.ss.formula.eval.ValueEval;

/**
 * Implementation for Excel REPT () function.
 * <p>
 * <b>Syntax</b>:<br> <b>REPT  </b>(<b>text</b>,<b>number_times</b> )<br>
 * <p>
 * Repeats text a given number of times. Use REPT to fill a cell with a number of instances of a text string.
 *
 * text : text The text that you want to repeat.
 * number_times:    A positive number specifying the number of times to repeat text.
 *
 * If number_times is 0 (zero), REPT returns "" (empty text).
 * If this argument contains a decimal value, this function ignores the numbers to the right side of the decimal point.
 *
 * The result of the REPT function cannot be longer than 32,767 characters, or REPT returns #VALUE!.
 */
public class Rept extends Fixed2ArgFunction  {

    @Override
    public ValueEval evaluate(int srcRowIndex, int srcColumnIndex, ValueEval text, ValueEval number_times) {

        ValueEval veText1;
        try {
            veText1 = OperandResolver.getSingleValue(text, srcRowIndex, srcColumnIndex);
        } catch (EvaluationException e) {
            return e.getErrorEval();
        }
        String strText1 = OperandResolver.coerceValueToString(veText1);
        double numberOfTime;
        try {
            numberOfTime = OperandResolver.coerceValueToDouble(number_times);
        } catch (EvaluationException e) {
            return ErrorEval.VALUE_INVALID;
        }

        int numberOfTimeInt = (int)numberOfTime;
        StringBuilder strb = new StringBuilder(strText1.length() * numberOfTimeInt);
        for(int i = 0; i < numberOfTimeInt; i++) {
            strb.append(strText1);
        }

        if (strb.length() > 32767) {
            return ErrorEval.VALUE_INVALID;
        }

        return new StringEval(strb.toString());
    }
}
