import java.util.regex.Pattern;

	/**

	 * Implementation of the PROPER function:

     * Normalizes all words (separated by non-word characters) by

     * making the first letter upper and the rest lower case.

	 */

	public static final Function PROPER = new SingleArgTextFunc() {

	    final Pattern nonAlphabeticPattern = Pattern.compile("\\P{IsAlphabetic}");

		protected ValueEval evaluate(String text) {

			StringBuilder sb = new StringBuilder();

			boolean shouldMakeUppercase = true;

			String lowercaseText = text.toLowerCase();

			String uppercaseText = text.toUpperCase();

			for(int i = 0; i < text.length(); ++i) {

				if (shouldMakeUppercase) {

					sb.append(uppercaseText.charAt(i));

				}

				else {

					sb.append(lowercaseText.charAt(i));

				}

				shouldMakeUppercase = nonAlphabeticPattern.matcher(text.subSequence(i, i + 1)).matches();

			}

			return new StringEval(sb.toString());

		}

	};

/* ====================================================================

   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.

==================================================================== */

package org.apache.poi.ss.formula.functions;

import junit.framework.AssertionFailedError;

import junit.framework.TestCase;

import org.apache.poi.hssf.usermodel.HSSFCell;

import org.apache.poi.hssf.usermodel.HSSFFormulaEvaluator;

import org.apache.poi.hssf.usermodel.HSSFSheet;

import org.apache.poi.hssf.usermodel.HSSFWorkbook;

import org.apache.poi.ss.usermodel.Cell;

import org.apache.poi.ss.usermodel.CellValue;

public final class TestProper extends TestCase {

    private HSSFCell cell11;

    private HSSFFormulaEvaluator evaluator;

    public void setUp() {

        HSSFWorkbook wb = new HSSFWorkbook();

        HSSFSheet sheet = wb.createSheet("new sheet");

        cell11 = sheet.createRow(0).createCell(0);

        cell11.setCellType(HSSFCell.CELL_TYPE_FORMULA);

        evaluator = new HSSFFormulaEvaluator(wb);

    }

    public void testValid() {

        confirm("PROPER(\"hi there\")", "Hi There");

        confirm("PROPER(\"what's up\")", "What'S Up");

        confirm("PROPER(\"I DON'T TH!NK SO!\")", "I Don'T Th!Nk So!");

        confirm("PROPER(\"drÜbö'ä éloş|ëè \")", "Drübö'Ä Éloş|Ëè ");

    }

    private void confirm(String formulaText, String expectedResult) {

        cell11.setCellFormula(formulaText);

        evaluator.clearAllCachedResultValues();

        CellValue cv = evaluator.evaluate(cell11);

        if (cv.getCellType() != Cell.CELL_TYPE_STRING) {

            throw new AssertionFailedError("Wrong result type: " + cv.formatAsString());

        }

        String actualValue = cv.getStringValue();

        assertEquals(expectedResult, actualValue);

    }

}