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/*!
* bytes
* Copyright(c) 2012-2014 TJ Holowaychuk
* Copyright(c) 2015 Jed Watson
* MIT Licensed
*/
'use strict';
/**
* Module exports.
* @public
*/
module.exports = bytes;
module.exports.format = format;
module.exports.parse = parse;
/**
* Module variables.
* @private
*/
var formatThousandsRegExp = /\B(?=(\d{3})+(?!\d))/g;
var formatDecimalsRegExp = /(?:\.0*|(\.[^0]+)0+)$/;
var map = {
b: 1,
kb: 1 << 10,
mb: 1 << 20,
gb: 1 << 30,
tb: Math.pow(1024, 4),
pb: Math.pow(1024, 5),
};
var parseRegExp = /^((-|\+)?(\d+(?:\.\d+)?)) *(kb|mb|gb|tb|pb)$/i;
/**
* Convert the given value in bytes into a string or parse to string to an integer in bytes.
*
* @param {string|number} value
* @param {{
* case: [string],
* decimalPlaces: [number]
* fixedDecimals: [boolean]
* thousandsSeparator: [string]
* unitSeparator: [string]
* }} [options] bytes options.
*
* @returns {string|number|null}
*/
function bytes(value, options) {
if (typeof value === 'string') {
return parse(value);
}
if (typeof value === 'number') {
return format(value, options);
}
return null;
}
/**
* Format the given value in bytes into a string.
*
* If the value is negative, it is kept as such. If it is a float,
* it is rounded.
*
* @param {number} value
* @param {object} [options]
* @param {number} [options.decimalPlaces=2]
* @param {number} [options.fixedDecimals=false]
* @param {string} [options.thousandsSeparator=]
* @param {string} [options.unit=]
* @param {string} [options.unitSeparator=]
*
* @returns {string|null}
* @public
*/
function format(value, options) {
if (!Number.isFinite(value)) {
return null;
}
var mag = Math.abs(value);
var thousandsSeparator = (options && options.thousandsSeparator) || '';
var unitSeparator = (options && options.unitSeparator) || '';
var decimalPlaces = (options && options.decimalPlaces !== undefined) ? options.decimalPlaces : 2;
var fixedDecimals = Boolean(options && options.fixedDecimals);
var unit = (options && options.unit) || '';
if (!unit || !map[unit.toLowerCase()]) {
if (mag >= map.pb) {
unit = 'PB';
} else if (mag >= map.tb) {
unit = 'TB';
} else if (mag >= map.gb) {
unit = 'GB';
} else if (mag >= map.mb) {
unit = 'MB';
} else if (mag >= map.kb) {
unit = 'KB';
} else {
unit = 'B';
}
}
var val = value / map[unit.toLowerCase()];
var str = val.toFixed(decimalPlaces);
if (!fixedDecimals) {
str = str.replace(formatDecimalsRegExp, '$1');
}
if (thousandsSeparator) {
str = str.split('.').map(function (s, i) {
return i === 0
? s.replace(formatThousandsRegExp, thousandsSeparator)
: s
}).join('.');
}
return str + unitSeparator + unit;
}
/**
* Parse the string value into an integer in bytes.
*
* If no unit is given, it is assumed the value is in bytes.
*
* @param {number|string} val
*
* @returns {number|null}
* @public
*/
function parse(val) {
if (typeof val === 'number' && !isNaN(val)) {
return val;
}
if (typeof val !== 'string') {
return null;
}
// Test if the string passed is valid
var results = parseRegExp.exec(val);
var floatValue;
var unit = 'b';
if (!results) {
// Nothing could be extracted from the given string
floatValue = parseInt(val, 10);
unit = 'b'
} else {
// Retrieve the value and the unit
floatValue = parseFloat(results[1]);
unit = results[4].toLowerCase();
}
if (isNaN(floatValue)) {
return null;
}
return Math.floor(map[unit] * floatValue);
}