roman-time.js

'use strict';

function isTime(time) {
    var regexn = /^([0-9]|0[0-9]|1[0-9]|2[0-3]):[0-5][0-9]$/;
    if (regexn.test(time)) {
        return true;
    }
}

function translationFromArabicToRoman(number) {
    if (!number) {
        return 'N';
    }
    var alphabet = [["M", 1000], ["CM", 900], ["D", 500], ["CD", 400], ["C", 100], ["XC", 90],
    ["L", 50], ["XL", 40], ["X", 10], ["IX", 9], ["V", 5], ["IV", 4], ["I", 1]];
    var cumTotal = 0;
    var i;
    var rom = "";
    for (i = 0; i < alphabet.length; i++) {
        while (cumTotal + alphabet[i][1] <= number) {
            cumTotal += alphabet[i][1];
            rom += alphabet[i][0];
        }
    }

    return rom;
}

function romanTime(time) {
    if (!isTime(time)) {
        throw new TypeError('Неверное время');
    }
    time = time.split(':');
    var hour = parseInt(time[0]);
    var minute = parseInt(time[1]);

    return translationFromArabicToRoman(hour) + ':' + translationFromArabicToRoman(minute);
}

module.exports = romanTime;