bangla-date-utils/dist/utils/banglaCalendar.js

A utility package for converting and formatting dates in the Bangla calendar system with support for Bangla numerals.

"use strict";
exports.__esModule = true;
exports.formatBanglaDateString = exports.getCurrentBanglaDate = exports.getBanglaWeekday = exports.convertBanglaToGregorian = exports.convertGregorianToBangla = exports.getDaysInBanglaMonth = exports.isBanglaLeapYear = exports.BANGLA_WEEKDAYS = exports.BANGLA_SEASONS = exports.BANGLA_MONTHS = void 0;
// Constants for Bangla calendar
exports.BANGLA_MONTHS = [
    "বৈশাখ",
    "জ্যৈষ্ঠ",
    "আষাঢ়",
    "শ্রাবণ",
    "ভাদ্র",
    "আশ্বিন",
    "কার্তিক",
    "অগ্রহায়ণ",
    "পৌষ",
    "মাঘ",
    "ফাল্গুন",
    "চৈত্র", // Choitro
];
exports.BANGLA_SEASONS = [
    "গ্রীষ্ম",
    "বর্ষা",
    "শরৎ",
    "হেমন্ত",
    "শীত",
    "বসন্ত", // Boshonto (Spring)
];
exports.BANGLA_WEEKDAYS = [
    "রবিবার",
    "সোমবার",
    "মঙ্গলবার",
    "বুধবার",
    "বৃহস্পতিবার",
    "শুক্রবার",
    "শনিবার", // Saturday
];
/**
 * Determines if the given Bangla year is a leap year
 * @param year Bangla year
 * @returns boolean indicating if it's a leap year
 */
var isBanglaLeapYear = function (year) {
    // Convert Bangla year to Gregorian year (approximate)
    var gregorianYear = year - 593;
    // Gregorian leap year calculation
    return (gregorianYear % 4 === 0 && gregorianYear % 100 !== 0) || gregorianYear % 400 === 0;
};
exports.isBanglaLeapYear = isBanglaLeapYear;
/**
 * Get the number of days in a Bangla month
 * @param month Bangla month (1-12)
 * @param year Bangla year
 * @returns number of days in the month
 */
var getDaysInBanglaMonth = function (month, year) {
    // Bangla months have either 30 or 31 days
    // Falgun (11th month) has 29 days in non-leap years and 30 days in leap years
    if (month === 11) {
        return (0, exports.isBanglaLeapYear)(year) ? 30 : 29;
    }
    // Chaitra (12th month) has 30 days
    if (month === 12) {
        return 30;
    }
    // Other months alternate between 31 and 30 days
    return month % 2 === 1 ? 31 : 30;
};
exports.getDaysInBanglaMonth = getDaysInBanglaMonth;
/**
 * Convert Gregorian date to Bangla date
 * @param date Gregorian date
 * @returns BanglaDate object
 */
var convertGregorianToBangla = function (date) {
    var gregorianDate = date.getDate();
    var gregorianMonth = date.getMonth() + 1; // 1-12
    var gregorianYear = date.getFullYear();
    var banglaDate;
    var banglaMonth;
    var banglaYear;
    // Bangla new year starts around April 14
    // This is a simplified calculation - a more accurate one would account for leap years
    if (gregorianMonth < 4 || (gregorianMonth === 4 && gregorianDate < 14)) {
        // Jan to mid-April: Bangla year is Gregorian year - 594
        banglaYear = gregorianYear - 594;
    }
    else {
        // Mid-April to Dec: Bangla year is Gregorian year - 593
        banglaYear = gregorianYear - 593;
    }
    // Approximate mapping of Gregorian to Bangla dates
    // This is a simplified version - a more accurate version would use astronomical calculations
    if (gregorianMonth === 4) {
        // April
        if (gregorianDate < 14) {
            banglaMonth = 12; // Chaitra
            banglaDate = gregorianDate + 17;
        }
        else {
            banglaMonth = 1; // Boishakh
            banglaDate = gregorianDate - 13;
        }
    }
    else if (gregorianMonth === 5) {
        // May
        if (gregorianDate < 15) {
            banglaMonth = 1; // Boishakh
            banglaDate = gregorianDate + 17;
        }
        else {
            banglaMonth = 2; // Jyoishtho
            banglaDate = gregorianDate - 14;
        }
    }
    else if (gregorianMonth === 6) {
        // June
        if (gregorianDate < 15) {
            banglaMonth = 2; // Jyoishtho
            banglaDate = gregorianDate + 17;
        }
        else {
            banglaMonth = 3; // Asharh
            banglaDate = gregorianDate - 14;
        }
    }
    else if (gregorianMonth === 7) {
        // July
        if (gregorianDate < 16) {
            banglaMonth = 3; // Asharh
            banglaDate = gregorianDate + 16;
        }
        else {
            banglaMonth = 4; // Shrabon
            banglaDate = gregorianDate - 15;
        }
    }
    else if (gregorianMonth === 8) {
        // August
        if (gregorianDate < 16) {
            banglaMonth = 4; // Shrabon
            banglaDate = gregorianDate + 16;
        }
        else {
            banglaMonth = 5; // Bhadro
            banglaDate = gregorianDate - 15;
        }
    }
    else if (gregorianMonth === 9) {
        // September
        if (gregorianDate < 16) {
            banglaMonth = 5; // Bhadro
            banglaDate = gregorianDate + 16;
        }
        else {
            banglaMonth = 6; // Ashwin
            banglaDate = gregorianDate - 15;
        }
    }
    else if (gregorianMonth === 10) {
        // October
        if (gregorianDate < 16) {
            banglaMonth = 6; // Ashwin
            banglaDate = gregorianDate + 15;
        }
        else {
            banglaMonth = 7; // Kartik
            banglaDate = gregorianDate - 15;
        }
    }
    else if (gregorianMonth === 11) {
        // November
        if (gregorianDate < 15) {
            banglaMonth = 7; // Kartik
            banglaDate = gregorianDate + 16;
        }
        else {
            banglaMonth = 8; // Ogrohayon
            banglaDate = gregorianDate - 14;
        }
    }
    else if (gregorianMonth === 12) {
        // December
        if (gregorianDate < 15) {
            banglaMonth = 8; // Ogrohayon
            banglaDate = gregorianDate + 16;
        }
        else {
            banglaMonth = 9; // Poush
            banglaDate = gregorianDate - 14;
        }
    }
    else if (gregorianMonth === 1) {
        // January
        if (gregorianDate < 14) {
            banglaMonth = 9; // Poush
            banglaDate = gregorianDate + 17;
        }
        else {
            banglaMonth = 10; // Magh
            banglaDate = gregorianDate - 13;
        }
    }
    else if (gregorianMonth === 2) {
        // February
        if (gregorianDate < 13) {
            banglaMonth = 10; // Magh
            banglaDate = gregorianDate + 18;
        }
        else {
            banglaMonth = 11; // Falgun
            banglaDate = gregorianDate - 12;
        }
    }
    else {
        // March
        if (gregorianDate < 15) {
            banglaMonth = 11; // Falgun
            banglaDate = gregorianDate + 16;
        }
        else {
            banglaMonth = 12; // Chaitra
            banglaDate = gregorianDate - 14;
        }
    }
    // Get season based on Bangla month
    var seasonIndex = Math.floor((banglaMonth - 1) / 2);
    if (seasonIndex > 5)
        seasonIndex = 5;
    return {
        year: banglaYear,
        month: banglaMonth,
        date: banglaDate,
        monthName: exports.BANGLA_MONTHS[banglaMonth - 1],
        season: exports.BANGLA_SEASONS[seasonIndex]
    };
};
exports.convertGregorianToBangla = convertGregorianToBangla;
/**
 * Convert Bangla date to Gregorian date
 * @param banglaDate Bangla date (day)
 * @param banglaMonth Bangla month (1-12)
 * @param banglaYear Bangla year
 * @returns JavaScript Date object
 */
var convertBanglaToGregorian = function (banglaDate, banglaMonth, banglaYear) {
    var gregorianYear = banglaYear + 593;
    var gregorianMonth = 0; // 0-11 for JavaScript Date
    var gregorianDate = 0;
    // Approximate mapping of Bangla to Gregorian dates
    // This is a simplified version - a more accurate version would use astronomical calculations
    if (banglaMonth === 1) {
        // Boishakh (mid-April to mid-May)
        if (banglaDate <= 18) {
            gregorianMonth = 3; // April
            gregorianDate = banglaDate + 13;
        }
        else {
            gregorianMonth = 4; // May
            gregorianDate = banglaDate - 18;
        }
    }
    else if (banglaMonth === 2) {
        // Jyoishtho (mid-May to mid-June)
        if (banglaDate <= 17) {
            gregorianMonth = 4; // May
            gregorianDate = banglaDate + 14;
        }
        else {
            gregorianMonth = 5; // June
            gregorianDate = banglaDate - 17;
        }
    }
    else if (banglaMonth === 3) {
        // Asharh (mid-June to mid-July)
        if (banglaDate <= 16) {
            gregorianMonth = 5; // June
            gregorianDate = banglaDate + 14;
        }
        else {
            gregorianMonth = 6; // July
            gregorianDate = banglaDate - 16;
        }
    }
    else if (banglaMonth === 4) {
        // Shrabon (mid-July to mid-August)
        if (banglaDate <= 16) {
            gregorianMonth = 6; // July
            gregorianDate = banglaDate + 15;
        }
        else {
            gregorianMonth = 7; // August
            gregorianDate = banglaDate - 16;
        }
    }
    else if (banglaMonth === 5) {
        // Bhadro (mid-August to mid-September)
        if (banglaDate <= 16) {
            gregorianMonth = 7; // August
            gregorianDate = banglaDate + 15;
        }
        else {
            gregorianMonth = 8; // September
            gregorianDate = banglaDate - 16;
        }
    }
    else if (banglaMonth === 6) {
        // Ashwin (mid-September to mid-October)
        if (banglaDate <= 15) {
            gregorianMonth = 8; // September
            gregorianDate = banglaDate + 15;
        }
        else {
            gregorianMonth = 9; // October
            gregorianDate = banglaDate - 15;
        }
    }
    else if (banglaMonth === 7) {
        // Kartik (mid-October to mid-November)
        if (banglaDate <= 16) {
            gregorianMonth = 9; // October
            gregorianDate = banglaDate + 15;
        }
        else {
            gregorianMonth = 10; // November
            gregorianDate = banglaDate - 16;
        }
    }
    else if (banglaMonth === 8) {
        // Ogrohayon (mid-November to mid-December)
        if (banglaDate <= 15) {
            gregorianMonth = 10; // November
            gregorianDate = banglaDate + 14;
        }
        else {
            gregorianMonth = 11; // December
            gregorianDate = banglaDate - 15;
        }
    }
    else if (banglaMonth === 9) {
        // Poush (mid-December to mid-January)
        if (banglaDate <= 16) {
            gregorianMonth = 11; // December
            gregorianDate = banglaDate + 14;
        }
        else {
            gregorianMonth = 0; // January
            gregorianDate = banglaDate - 16;
            gregorianYear += 1;
        }
    }
    else if (banglaMonth === 10) {
        // Magh (mid-January to mid-February)
        if (banglaDate <= 18) {
            gregorianMonth = 0; // January
            gregorianDate = banglaDate + 13;
        }
        else {
            gregorianMonth = 1; // February
            gregorianDate = banglaDate - 18;
        }
    }
    else if (banglaMonth === 11) {
        // Falgun (mid-February to mid-March)
        if (banglaDate <= 16) {
            gregorianMonth = 1; // February
            gregorianDate = banglaDate + 12;
        }
        else {
            gregorianMonth = 2; // March
            gregorianDate = banglaDate - 16;
        }
    }
    else {
        // Chaitra (mid-March to mid-April)
        if (banglaDate <= 17) {
            gregorianMonth = 2; // March
            gregorianDate = banglaDate + 14;
        }
        else {
            gregorianMonth = 3; // April
            gregorianDate = banglaDate - 17;
        }
    }
    return new Date(gregorianYear, gregorianMonth, gregorianDate);
};
exports.convertBanglaToGregorian = convertBanglaToGregorian;
/**
 * Get the Bangla weekday name for a given date
 * @param date JavaScript Date object
 * @returns Bangla weekday name
 */
var getBanglaWeekday = function (date) {
    var dayIndex = date.getDay(); // 0-6, where 0 is Sunday
    return exports.BANGLA_WEEKDAYS[dayIndex];
};
exports.getBanglaWeekday = getBanglaWeekday;
/**
 * Get the current Bangla date
 * @returns BanglaDate object for the current date
 */
var getCurrentBanglaDate = function () {
    return (0, exports.convertGregorianToBangla)(new Date());
};
exports.getCurrentBanglaDate = getCurrentBanglaDate;
/**
 * Format a Bangla date as a string
 * @param banglaDate BanglaDate object
 * @param format Format string (e.g., 'full', 'medium', 'short')
 * @returns Formatted Bangla date string
 */
var formatBanglaDateString = function (banglaDate, format) {
    if (format === void 0) { format = "medium"; }
    var date = banglaDate.date, month = banglaDate.month, year = banglaDate.year, monthName = banglaDate.monthName, season = banglaDate.season;
    // Convert numbers to Bangla numerals
    var banglaNumerals = ["০", "১", "২", "৩", "৪", "৫", "৬", "৭", "৮", "৯"];
    var toBanglaNumerals = function (num) {
        return num
            .toString()
            .split("")
            .map(function (digit) { return banglaNumerals[Number.parseInt(digit)]; })
            .join("");
    };
    var banglaDateNum = toBanglaNumerals(date);
    var banglaYear = toBanglaNumerals(year);
    if (format === "full") {
        return "".concat(banglaDateNum, " ").concat(monthName, " ").concat(banglaYear, " (").concat(season, ")");
    }
    else if (format === "short") {
        return "".concat(banglaDateNum, "/").concat(toBanglaNumerals(month), "/").concat(banglaYear);
    }
    else {
        // medium format
        return "".concat(banglaDateNum, " ").concat(monthName, " ").concat(banglaYear);
    }
};
exports.formatBanglaDateString = formatBanglaDateString;