parseStringSize.js

"use strict";

var multipliers = {
    k: Math.pow(1024, 1),
    m: Math.pow(1024, 2),
    g: Math.pow(1024, 3),
    t: Math.pow(1024, 4)
};

var regex = /([0-9]+[.,]?[0-9]*) *([kmgt]?)/ig;

/**
 * Parse a size as a string,
 * @param string
 * @param unit
 * @returns {int|null}
 */
var parseStringSize = function parseStringSize (string, unit) {
    var result,
        value;

    if (result = regex.exec(string)) {
        unit = unit ? unit[0] : result[2];
        unit = unit.toLowerCase();
        value = parseFloat(result[1].replace(',', '.'));

        if (multipliers.hasOwnProperty(unit)) {
            value = value * multipliers[unit];
        }

        return value;
    }

    return null;
};

module.exports = parseStringSize;