/*
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 *    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
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package org.apache.poi.ss.util;

import java.io.File;
import java.io.FileOutputStream;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Arrays;
import java.util.Date;
import java.util.Locale;

import junit.framework.TestCase;

import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.CellStyle;
import org.apache.poi.ss.usermodel.DataFormat;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.util.TempFile;

public final class TestDateFormatConverter extends TestCase {
    private void outputLocaleDataFormats( Date date, boolean dates, boolean times, int style, String styleName ) throws Exception {

        Workbook workbook = new HSSFWorkbook();
        String sheetName;
        if( dates ) {
            if( times ) {
                sheetName = "DateTimes";
            } else {
                sheetName = "Dates";
            }
        } else {
            sheetName = "Times";
        }
        Sheet sheet = workbook.createSheet(sheetName);
        Row header = sheet.createRow(0);
        header.createCell(0).setCellValue("locale");
        header.createCell(1).setCellValue("DisplayName");
        header.createCell(2).setCellValue("Excel " + styleName);
        header.createCell(3).setCellValue("java.text.DateFormat");
        header.createCell(4).setCellValue("Equals");
        header.createCell(5).setCellValue("Java pattern");
        header.createCell(6).setCellValue("Excel pattern");

        int rowNum = 1;
        for( Locale locale : DateFormat.getAvailableLocales() ) {
            try {
                Row row = sheet.createRow(rowNum++);
    
                row.createCell(0).setCellValue(locale.toString());
                row.createCell(1).setCellValue(locale.getDisplayName());
    
                DateFormat dateFormat;
                if( dates ) {
                    if( times ) {
                        dateFormat = DateFormat.getDateTimeInstance(style, style, locale);
                    } else {
                        dateFormat = DateFormat.getDateInstance(style, locale);
                    }
                } else {
                    dateFormat = DateFormat.getTimeInstance(style, locale);
                }
    
                Cell cell = row.createCell(2);
    
                cell.setCellValue(date);
                CellStyle cellStyle = row.getSheet().getWorkbook().createCellStyle();
    
                String javaDateFormatPattern = ((SimpleDateFormat)dateFormat).toPattern();
                String excelFormatPattern = DateFormatConverter.convert(locale, javaDateFormatPattern);
    
                DataFormat poiFormat = row.getSheet().getWorkbook().createDataFormat();
                cellStyle.setDataFormat(poiFormat.getFormat(excelFormatPattern));
                row.createCell(3).setCellValue(dateFormat.format(date));
    
                cell.setCellStyle(cellStyle);
    
                // the formula returns TRUE is the formatted date in column C equals to the string in column D
                row.createCell(4).setCellFormula("TEXT(C"+rowNum+",G"+rowNum+")=D" + rowNum);
                row.createCell(5).setCellValue(javaDateFormatPattern);
                row.createCell(6).setCellValue(excelFormatPattern);
            } catch (Exception e) {
                throw new RuntimeException("Failed for locale: " + locale + ", having locales: " + 
                        Arrays.toString(DateFormat.getAvailableLocales()), e);
            }
        }

        File outputFile = TempFile.createTempFile("Locale" + sheetName + styleName, ".xlsx");
        FileOutputStream outputStream = new FileOutputStream(outputFile);
        try {
            workbook.write(outputStream);
        } finally {
            outputStream.close();
        }

        System.out.println("Open " + outputFile.getAbsolutePath()+" in Excel");
    }

    public void testJavaDateFormatsInExcel() throws Exception {
        Date date = new Date();

        outputLocaleDataFormats(date, true, false, DateFormat.DEFAULT, "Default" );
        outputLocaleDataFormats(date, true, false, DateFormat.SHORT, "Short" );
        outputLocaleDataFormats(date, true, false, DateFormat.MEDIUM, "Medium" );
        outputLocaleDataFormats(date, true, false, DateFormat.LONG, "Long" );
        outputLocaleDataFormats(date, true, false, DateFormat.FULL, "Full" );

        outputLocaleDataFormats(date, true, true, DateFormat.DEFAULT, "Default" );
        outputLocaleDataFormats(date, true, true, DateFormat.SHORT, "Short" );
        outputLocaleDataFormats(date, true, true, DateFormat.MEDIUM, "Medium" );
        outputLocaleDataFormats(date, true, true, DateFormat.LONG, "Long" );
        outputLocaleDataFormats(date, true, true, DateFormat.FULL, "Full" );

        outputLocaleDataFormats(date, false, true, DateFormat.DEFAULT, "Default" );
        outputLocaleDataFormats(date, false, true, DateFormat.SHORT, "Short" );
        outputLocaleDataFormats(date, false, true, DateFormat.MEDIUM, "Medium" );
        outputLocaleDataFormats(date, false, true, DateFormat.LONG, "Long" );
        outputLocaleDataFormats(date, false, true, DateFormat.FULL, "Full" );
    }
    
    public void testJDK8EmptyLocale() {
        // JDK 8 seems to add an empty locale-string to the list returned via DateFormat.getAvailableLocales()
        // therefore we now cater for this special locale as well
        DateFormatConverter.getPrefixForLocale(new Locale(""));
    }

}