Declarative ways to get time in months|days|hours|seconds|miliseconds later (or of) months|days|minutes|seconds

timeIn.js

/**
 * Get time in months|days|hours|seconds|miliseconds later (or of) months|days|hours|seconds|miliseconds
 * 
 * Examples:
 *  timeIn('second').later(30).minutes();
 *  timeIn('second').of(2).days();
 * 
 * @param {string} name 
 * @return {object} { later, of }
 */
exports.timeIn = (name = 'milisecond') => {
    const output = (timeInMs) => {
        const milisecondTo = {
            month() {
                return timeInMs / 1000 / 60 / 60 / 24 / 30;
            },
            day() {
                return timeInMs / 1000 / 60 / 60 / 24;
            },
            hour() {
                return timeInMs / 1000 / 60 / 60;
            },
            minute() {
                return timeInMs / 1000 / 60;
            },
            second() {
                return timeInMs / 1000;
            },
            milisecond() {
                return timeInMs;
            }
        }
        name = name.replace(/s+$/, '');
        try {
            return milisecondTo[name]();
        } catch (error) {
            throw new Error(name + " is not a function");
        }
    }
    const timeMaker = (number, from = Date.now()) => {
        if(typeof number != 'number') {
            throw new Error("number must be in number type");
        }
        const milisecondBy = {
            month() {
                return from + (number * 1000 * 60 * 60 * 24 * 30)
            },
            day() {
                return from + (number * 1000 * 60 * 60 * 24)
            },
            hour() {
                return from + (number * 1000 * 60 * 60)
            },
            minute() {
                return from + (number * 1000 * 60)
            },
            second() {
                return from + (number * 1000)
            },
            milisecond() {
                return from + number
            },
        }
        const toOutput = (name) => {
            name = name.replace(/s+$/, '');
            try {
                const timeInMs = milisecondBy[name]();
                return output(timeInMs);
            } catch (error) {
                throw new Error(name + " is not a function");
            }
        }
        return {
            month: () => toOutput('month'),
            months: () => toOutput('month'),
            day: () => toOutput('day'),
            days: () => toOutput('day'),
            hour: () => toOutput('hour'),
            hours: () => toOutput('hour'),
            minute: () => toOutput('minute'),
            minutes: () => toOutput('minute'),
            second: () => toOutput('second'),
            seconds: () => toOutput('second'),
            milisecond: () => toOutput('milisecond'),
            miliseconds: () => toOutput('milisecond'),
        }
    }
    const later = number => timeMaker(number);
    const of = number => timeMaker(number, 0);

    return { later, of }
}