/* ====================================================================
   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.examples.ss;

import java.io.FileOutputStream;
import java.util.Calendar;
import java.util.HashMap;
import java.util.Map;

import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.BorderStyle;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.CellStyle;
import org.apache.poi.ss.usermodel.FillPatternType;
import org.apache.poi.ss.usermodel.Font;
import org.apache.poi.ss.usermodel.HorizontalAlignment;
import org.apache.poi.ss.usermodel.IndexedColors;
import org.apache.poi.ss.usermodel.PrintSetup;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.VerticalAlignment;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.ss.util.CellRangeAddress;
import org.apache.poi.util.LocaleUtil;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

/**
 * A  monthly calendar created using Apache POI. Each month is on a separate sheet.
 * <pre>
 * Usage:
 * CalendarDemo -xls|xlsx <year>
 * </pre>
 *
 * @author Yegor Kozlov
 */
@SuppressWarnings({"java:S106","java:S4823","java:S1192"})
public final class CalendarDemo {

    private static final String[] days = {
            "Sunday", "Monday", "Tuesday",
            "Wednesday", "Thursday", "Friday", "Saturday"};

    private static final String[]  months = {
            "January", "February", "March","April", "May", "June","July", "August",
            "September","October", "November", "December"};

    private CalendarDemo() {}

    public static void main(String[] args) throws Exception {

        Calendar calendar = LocaleUtil.getLocaleCalendar();
        boolean xlsx = true;
        for (String arg : args) {
            if (arg.charAt(0) == '-') {
                xlsx = arg.equals("-xlsx");
            } else {
                calendar.set(Calendar.YEAR, Integer.parseInt(arg));
            }
        }
        int year = calendar.get(Calendar.YEAR);

        try (Workbook wb = xlsx ? new XSSFWorkbook() : new HSSFWorkbook()) {

            Map<String, CellStyle> styles = createStyles(wb);

            for (int month = 0; month < 12; month++) {
                calendar.set(Calendar.MONTH, month);
                calendar.set(Calendar.DAY_OF_MONTH, 1);
                //create a sheet for each month
                Sheet sheet = wb.createSheet(months[month]);

                //turn off gridlines
                sheet.setDisplayGridlines(false);
                sheet.setPrintGridlines(false);
                sheet.setFitToPage(true);
                sheet.setHorizontallyCenter(true);
                PrintSetup printSetup = sheet.getPrintSetup();
                printSetup.setLandscape(true);

                //the following three statements are required only for HSSF
                sheet.setAutobreaks(true);
                printSetup.setFitHeight((short) 1);
                printSetup.setFitWidth((short) 1);

                //the header row: centered text in 48pt font
                Row headerRow = sheet.createRow(0);
                headerRow.setHeightInPoints(80);
                Cell titleCell = headerRow.createCell(0);
                titleCell.setCellValue(months[month] + " " + year);
                titleCell.setCellStyle(styles.get("title"));
                sheet.addMergedRegion(CellRangeAddress.valueOf("$A$1:$N$1"));

                //header with month titles
                Row monthRow = sheet.createRow(1);
                for (int i = 0; i < days.length; i++) {
                    //set column widths, the width is measured in units of 1/256th of a character width
                    sheet.setColumnWidth(i * 2, 5 * 256); //the column is 5 characters wide
                    sheet.setColumnWidth(i * 2 + 1, 13 * 256); //the column is 13 characters wide
                    sheet.addMergedRegion(new CellRangeAddress(1, 1, i * 2, i * 2 + 1));
                    Cell monthCell = monthRow.createCell(i * 2);
                    monthCell.setCellValue(days[i]);
                    monthCell.setCellStyle(styles.get("month"));
                }

                int cnt = 1, day = 1;
                int rownum = 2;
                for (int j = 0; j < 6; j++) {
                    Row row = sheet.createRow(rownum++);
                    row.setHeightInPoints(100);
                    for (int i = 0; i < days.length; i++) {
                        Cell dayCell_1 = row.createCell(i * 2);
                        Cell dayCell_2 = row.createCell(i * 2 + 1);

                        int day_of_week = calendar.get(Calendar.DAY_OF_WEEK);
                        if (cnt >= day_of_week && calendar.get(Calendar.MONTH) == month) {
                            dayCell_1.setCellValue(day);
                            calendar.set(Calendar.DAY_OF_MONTH, ++day);

                            if (i == 0 || i == days.length - 1) {
                                dayCell_1.setCellStyle(styles.get("weekend_left"));
                                dayCell_2.setCellStyle(styles.get("weekend_right"));
                            } else {
                                dayCell_1.setCellStyle(styles.get("workday_left"));
                                dayCell_2.setCellStyle(styles.get("workday_right"));
                            }
                        } else {
                            dayCell_1.setCellStyle(styles.get("grey_left"));
                            dayCell_2.setCellStyle(styles.get("grey_right"));
                        }
                        cnt++;
                    }
                    if (calendar.get(Calendar.MONTH) > month) break;
                }
            }

            // Write the output to a file
            String file = "calendar.xls";
            if (wb instanceof XSSFWorkbook) file += "x";

            try (FileOutputStream out = new FileOutputStream(file)) {
                wb.write(out);
            }
        }
    }

    /**
     * cell styles used for formatting calendar sheets
     */
    private static Map<String, CellStyle> createStyles(Workbook wb){
        Map<String, CellStyle> styles = new HashMap<>();

        short borderColor = IndexedColors.GREY_50_PERCENT.getIndex();

        CellStyle style;
        Font titleFont = wb.createFont();
        titleFont.setFontHeightInPoints((short)48);
        titleFont.setColor(IndexedColors.DARK_BLUE.getIndex());
        style = wb.createCellStyle();
        style.setAlignment(HorizontalAlignment.CENTER);
        style.setVerticalAlignment(VerticalAlignment.CENTER);
        style.setFont(titleFont);
        styles.put("title", style);

        Font monthFont = wb.createFont();
        monthFont.setFontHeightInPoints((short)12);
        monthFont.setColor(IndexedColors.WHITE.getIndex());
        monthFont.setBold(true);
        style = wb.createCellStyle();
        style.setAlignment(HorizontalAlignment.CENTER);
        style.setVerticalAlignment(VerticalAlignment.CENTER);
        style.setFillForegroundColor(IndexedColors.DARK_BLUE.getIndex());
        style.setFillPattern(FillPatternType.SOLID_FOREGROUND);
        style.setFont(monthFont);
        styles.put("month", style);

        Font dayFont = wb.createFont();
        dayFont.setFontHeightInPoints((short)14);
        dayFont.setBold(true);
        style = wb.createCellStyle();
        style.setAlignment(HorizontalAlignment.LEFT);
        style.setVerticalAlignment(VerticalAlignment.TOP);
        style.setFillForegroundColor(IndexedColors.LIGHT_CORNFLOWER_BLUE.getIndex());
        style.setFillPattern(FillPatternType.SOLID_FOREGROUND);
        style.setBorderLeft(BorderStyle.THIN);
        style.setLeftBorderColor(borderColor);
        style.setBorderBottom(BorderStyle.THIN);
        style.setBottomBorderColor(borderColor);
        style.setFont(dayFont);
        styles.put("weekend_left", style);

        style = wb.createCellStyle();
        style.setAlignment(HorizontalAlignment.CENTER);
        style.setVerticalAlignment(VerticalAlignment.TOP);
        style.setFillForegroundColor(IndexedColors.LIGHT_CORNFLOWER_BLUE.getIndex());
        style.setFillPattern(FillPatternType.SOLID_FOREGROUND);
        style.setBorderRight(BorderStyle.THIN);
        style.setRightBorderColor(borderColor);
        style.setBorderBottom(BorderStyle.THIN);
        style.setBottomBorderColor(borderColor);
        styles.put("weekend_right", style);

        style = wb.createCellStyle();
        style.setAlignment(HorizontalAlignment.LEFT);
        style.setVerticalAlignment(VerticalAlignment.TOP);
        style.setBorderLeft(BorderStyle.THIN);
        style.setFillForegroundColor(IndexedColors.WHITE.getIndex());
        style.setFillPattern(FillPatternType.SOLID_FOREGROUND);
        style.setLeftBorderColor(borderColor);
        style.setBorderBottom(BorderStyle.THIN);
        style.setBottomBorderColor(borderColor);
        style.setFont(dayFont);
        styles.put("workday_left", style);

        style = wb.createCellStyle();
        style.setAlignment(HorizontalAlignment.CENTER);
        style.setVerticalAlignment(VerticalAlignment.TOP);
        style.setFillForegroundColor(IndexedColors.WHITE.getIndex());
        style.setFillPattern(FillPatternType.SOLID_FOREGROUND);
        style.setBorderRight(BorderStyle.THIN);
        style.setRightBorderColor(borderColor);
        style.setBorderBottom(BorderStyle.THIN);
        style.setBottomBorderColor(borderColor);
        styles.put("workday_right", style);

        style = wb.createCellStyle();
        style.setBorderLeft(BorderStyle.THIN);
        style.setFillForegroundColor(IndexedColors.GREY_25_PERCENT.getIndex());
        style.setFillPattern(FillPatternType.SOLID_FOREGROUND);
        style.setBorderBottom(BorderStyle.THIN);
        style.setBottomBorderColor(borderColor);
        styles.put("grey_left", style);

        style = wb.createCellStyle();
        style.setFillForegroundColor(IndexedColors.GREY_25_PERCENT.getIndex());
        style.setFillPattern(FillPatternType.SOLID_FOREGROUND);
        style.setBorderRight(BorderStyle.THIN);
        style.setRightBorderColor(borderColor);
        style.setBorderBottom(BorderStyle.THIN);
        style.setBottomBorderColor(borderColor);
        styles.put("grey_right", style);

        return styles;
    }
}