C13Date Object

c13date.js

const monthNames = [
    'Capricornus',
    'Aquarius',
    'Pisces',
    'Aries',
    'Taurus',
    'Gemini',
    'Cancer',
    'Leo',
    'Virgo',
    'Libra',
    'Scorpius',
    'Sagittarius',
    'Serpentarius',
];

const dayNames = [
    'Solis',
    'Lunae',
    'Martis',
    'Mercurii',
    'Iovis',
    'Veneris',
    'Saturni',
    'Terra',
];

const SECOND = 1000;
const MINUTE = SECOND * 60;
const HOUR = MINUTE * 60;
const DAY = HOUR * 24;
const MONTH = DAY * 28;

const C13Date = (() => {
    function pad(number, length) {
        const current = number.toString();
        if (current.length >= length)
            return current;

        return ('0'.repeat(length) + current).substr(-length);
    }

    function cls(time) {
        if (typeof time === 'undefined')
            time = Date.now();

        if (!['string', 'object', 'number'].includes(typeof time)
            || !time instanceof Date)
            throw 'Invalid arguement error for C13Date constructor.';

        const isIsoDate = typeof time === 'string' && time.length === 10 && time.split('-').length === 3;

        const def = new Date();
        const _time = new Date(isIsoDate ? def : (time === '' ? def : time));
        this.setTime(_time.getTime());

        if (isIsoDate) {
            const broken = time.split('-');
            const year = parseInt(broken[0]);
            const month = parseInt(broken[1]) - 1;
            const date = parseInt(broken[2]);

            if ((month == 12 && date <= 30) || (month < 12 && date <= 28)) {
                this.setFullYear(year);
                this.setMonth(month);
                this.setDate(date);
            }
        }
    }
    const ins = cls.prototype;

    // static

    cls.now = function () {
        Date.now.apply(this, arguments);
    };

    cls.parse = function () {
        Date.parse.apply(this, arguments);
    };

    cls.UTC = function () {
        Date.UTC.apply(this, arguments);
    };

    // instance

    ins.getDate = function () {
        const base = this._internal - this._start;
        const month = base / MONTH | 0;
        const date = (base % MONTH) / DAY | 0;

        if (month < 13)
            return date + 1;

        return date + 29;
    };

    ins.getDay = function () {
        const date = this.getDate() - 1;
        if (date > 27)
            return 7;

        return date % 7;
    };

    ins.getFullYear = function () {
        return (new Date(this._internal)).getUTCFullYear();
    };

    ins.getHours = function () {
        const base = this._internal - this._start;
        return (base % DAY) / HOUR | 0;
    };

    ins.getMilliseconds = function () {
        const base = this._internal - this._start;
        return base % SECOND;
    };

    ins.getMinutes = function () {
        const base = this._internal - this._start;
        return (base % HOUR) / MINUTE | 0;
    };

    ins.getMonth = function () {
        const base = this._internal - this._start;
        return Math.min((base / MONTH | 0), 12);
    };

    ins.getSeconds = function () {
        const base = this._internal - this._start;
        return (base % MINUTE) / SECOND | 0;
    };

    ins.getTime = function () {
        return this._internal;
    };

    ins.getTimezoneOffset = function () {
        return 0;
    };

    ins.getUTCDate = ins.getDate;
    ins.getUTCDay = ins.getDay;
    ins.getUTCFullYear = ins.getFullYear;
    ins.getUTCHours = ins.getHours;
    ins.getUTCMilliseconds = ins.getMilliseconds;
    ins.getUTCMinutes = ins.getMinutes;
    ins.getUTCMonth = ins.getMonth;
    ins.getUTCSeconds = ins.getSeconds;

    ins.getYear = function () {
        return (new Date(this._internal)).getYear();
    };

    ins.isLeapYear = function () {
        const n = this.getFullYear();
        return n % 400 === 0 || (n % 100 !== 0 && n % 4 === 0);
    };

    ins.setDate = function (date) {
        const offset = (this.getDate() - 1) * DAY;
        this._internal += ((date - 1) * DAY) - offset;
        this.setTime(this._internal);
    };

    ins.setFullYear = function (year) {
        const base = this._internal - this._start;
        this._start = Date.parse(year.toString());
        this._internal = this._start + base;
    };

    ins.setHours = function (hours) {
        const offset = this.getHours() * HOUR;
        this._internal += (hours * HOUR) - offset;
        this.setTime(this._internal);
    };

    ins.setMilliseconds = function (milliseconds) {
        const offset = this.getMilliseconds();
        this._internal += milliseconds - offset;
        this.setTime(this._internal);
    };

    ins.setMinutes = function (minutes) {
        const offset = this.getMinutes() * MINUTE;
        this._internal += (minutes * MINUTE) - offset;
        this.setTime(this._internal);
    };

    ins.setMonth = function (month) {
        const offset = this.getMonth() * MONTH;
        this._internal += (month * MONTH) - offset;
        this.setTime(this._internal);
    };

    ins.setSeconds = function (seconds) {
        const offset = this.getSeconds() * SECOND;
        this._internal += (seconds * SECOND) - offset;
        this.setTime(this._internal);
    };

    ins.setTime = function (time) {
        this._internal = time;
        this._start = Date.parse((new Date(this._internal)).getUTCFullYear().toString());
    };

    ins.setUTCDate = ins.setDate;
    ins.setUTCDay = ins.setDay;
    ins.setUTCFullYear = ins.setFullYear;
    ins.setUTCHours = ins.setHours;
    ins.setUTCMilliseconds = ins.setMilliseconds;
    ins.setUTCMinutes = ins.setMinutes;
    ins.setUTCMonth = ins.setMonth;
    ins.setUTCSeconds = ins.setSeconds;

    ins.setYear = function (year) {
        const dummy = new Date(0);
        dummy.setYear(year);
        this.setFullYear(dummy.getUTCFullYear());
    }

    ins.toDateString = function () {
        return [
            this.getFullYear(),
            monthNames[this.getMonth()],
            this.getDate() + ',',
            dayNames[this.getDay()],
        ].join(' ');
    };

    ins.toISOString = function () {
        return [
            pad(this.getFullYear(), 4),
            '-',
            pad(this.getMonth() + 1, 2),
            '-',
            pad(this.getDate(), 2),
            'T',
            pad(this.getHours(), 2),
            ':',
            pad(this.getMinutes(), 2),
            ':',
            pad(this.getSeconds(), 2),
            '.',
            pad(this.getMilliseconds(), 3),
            'Z'
        ].join('');
    };

    ins.toJSON = ins.toISOString;

    ins.toGMTString = function () {
        return [
            this.toDateString(),
            this.toLocaleTimeString(),
            'UTC',
        ].join(' ');
    };

    ins.toLocaleDateString = ins.toDateString;
    ins.toLocaleString = ins.toGMTString;

    ins.toLocaleTimeString = function () {
        return [
            pad(this.getHours(), 2),
            pad(this.getMinutes(), 2),
            pad(this.getSeconds(), 2),
        ].join(':');
    };

    ins.toString = ins.toGMTString;
    ins.toTimeString = ins.toLocaleTimeString;
    ins.toUTCString = ins.toGMTString;

    ins.valueOf = function () {
        return this._internal;
    }

    cls.monthNames = monthNames;
    cls.dayNames = dayNames;

    return cls;
})();

if (typeof window !== 'undefined') {
    window.C13Date = C13Date;
}
if (typeof module !== 'undefined') {
    module.exports = C13Date;
}