@airgap/coinlib-core
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The @airgap/coinlib-core is a protocol agnostic library to prepare, sign and broadcast cryptocurrency transactions.
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JavaScript
'use strict'
/** Highest positive signed 32-bit float value */
const maxInt = 2147483647 // aka. 0x7FFFFFFF or 2^31-1
/** Bootstring parameters */
const base = 36
const tMin = 1
const tMax = 26
const skew = 38
const damp = 700
const initialBias = 72
const initialN = 128 // 0x80
const delimiter = '-' // '\x2D'
/** Regular expressions */
const regexPunycode = /^xn--/
const regexNonASCII = /[^\0-\x7E]/ // non-ASCII chars
const regexSeparators = /[\x2E\u3002\uFF0E\uFF61]/g // RFC 3490 separators
/** Error messages */
const errors = {
overflow: 'Overflow: input needs wider integers to process',
'not-basic': 'Illegal input >= 0x80 (not a basic code point)',
'invalid-input': 'Invalid input'
}
/** Convenience shortcuts */
const baseMinusTMin = base - tMin
const floor = Math.floor
const stringFromCharCode = String.fromCharCode
/*--------------------------------------------------------------------------*/
/**
* A generic error utility function.
* @private
* @param {String} type The error type.
* @returns {Error} Throws a `RangeError` with the applicable error message.
*/
function error(type) {
throw new RangeError(errors[type])
}
/**
* A generic `Array#map` utility function.
* @private
* @param {Array} array The array to iterate over.
* @param {Function} callback The function that gets called for every array
* item.
* @returns {Array} A new array of values returned by the callback function.
*/
function map(array, fn) {
const result = []
let length = array.length
while (length--) {
result[length] = fn(array[length])
}
return result
}
/**
* A simple `Array#map`-like wrapper to work with domain name strings or email
* addresses.
* @private
* @param {String} domain The domain name or email address.
* @param {Function} callback The function that gets called for every
* character.
* @returns {Array} A new string of characters returned by the callback
* function.
*/
function mapDomain(string, fn) {
const parts = string.split('@')
let result = ''
if (parts.length > 1) {
// In email addresses, only the domain name should be punycoded. Leave
// the local part (i.e. everything up to `@`) intact.
result = parts[0] + '@'
string = parts[1]
}
// Avoid `split(regex)` for IE8 compatibility. See #17.
string = string.replace(regexSeparators, '\x2E')
const labels = string.split('.')
const encoded = map(labels, fn).join('.')
return result + encoded
}
/**
* Creates an array containing the numeric code points of each Unicode
* character in the string. While JavaScript uses UCS-2 internally,
* this function will convert a pair of surrogate halves (each of which
* UCS-2 exposes as separate characters) into a single code point,
* matching UTF-16.
* @see `punycode.ucs2.encode`
* @see <https://mathiasbynens.be/notes/javascript-encoding>
* @memberOf punycode.ucs2
* @name decode
* @param {String} string The Unicode input string (UCS-2).
* @returns {Array} The new array of code points.
*/
function ucs2decode(string) {
const output = []
let counter = 0
const length = string.length
while (counter < length) {
const value = string.charCodeAt(counter++)
if (value >= 0xd800 && value <= 0xdbff && counter < length) {
// It's a high surrogate, and there is a next character.
const extra = string.charCodeAt(counter++)
if ((extra & 0xfc00) == 0xdc00) {
// Low surrogate.
output.push(((value & 0x3ff) << 10) + (extra & 0x3ff) + 0x10000)
} else {
// It's an unmatched surrogate; only append this code unit, in case the
// next code unit is the high surrogate of a surrogate pair.
output.push(value)
counter--
}
} else {
output.push(value)
}
}
return output
}
/**
* Creates a string based on an array of numeric code points.
* @see `punycode.ucs2.decode`
* @memberOf punycode.ucs2
* @name encode
* @param {Array} codePoints The array of numeric code points.
* @returns {String} The new Unicode string (UCS-2).
*/
const ucs2encode = (array) => String.fromCodePoint(...array)
/**
* Converts a basic code point into a digit/integer.
* @see `digitToBasic()`
* @private
* @param {Number} codePoint The basic numeric code point value.
* @returns {Number} The numeric value of a basic code point (for use in
* representing integers) in the range `0` to `base - 1`, or `base` if
* the code point does not represent a value.
*/
const basicToDigit = function (codePoint) {
if (codePoint - 0x30 < 0x0a) {
return codePoint - 0x16
}
if (codePoint - 0x41 < 0x1a) {
return codePoint - 0x41
}
if (codePoint - 0x61 < 0x1a) {
return codePoint - 0x61
}
return base
}
/**
* Converts a digit/integer into a basic code point.
* @see `basicToDigit()`
* @private
* @param {Number} digit The numeric value of a basic code point.
* @returns {Number} The basic code point whose value (when used for
* representing integers) is `digit`, which needs to be in the range
* `0` to `base - 1`. If `flag` is non-zero, the uppercase form is
* used; else, the lowercase form is used. The behavior is undefined
* if `flag` is non-zero and `digit` has no uppercase form.
*/
const digitToBasic = function (digit, flag) {
// 0..25 map to ASCII a..z or A..Z
// 26..35 map to ASCII 0..9
return digit + 22 + 75 * (digit < 26) - ((flag != 0) << 5)
}
/**
* Bias adaptation function as per section 3.4 of RFC 3492.
* https://tools.ietf.org/html/rfc3492#section-3.4
* @private
*/
const adapt = function (delta, numPoints, firstTime) {
let k = 0
delta = firstTime ? floor(delta / damp) : delta >> 1
delta += floor(delta / numPoints)
for (; /* no initialization */ delta > (baseMinusTMin * tMax) >> 1; k += base) {
delta = floor(delta / baseMinusTMin)
}
return floor(k + ((baseMinusTMin + 1) * delta) / (delta + skew))
}
/**
* Converts a Punycode string of ASCII-only symbols to a string of Unicode
* symbols.
* @memberOf punycode
* @param {String} input The Punycode string of ASCII-only symbols.
* @returns {String} The resulting string of Unicode symbols.
*/
const decode = function (input) {
// Don't use UCS-2.
const output = []
const inputLength = input.length
let i = 0
let n = initialN
let bias = initialBias
// Handle the basic code points: let `basic` be the number of input code
// points before the last delimiter, or `0` if there is none, then copy
// the first basic code points to the output.
let basic = input.lastIndexOf(delimiter)
if (basic < 0) {
basic = 0
}
for (let j = 0; j < basic; ++j) {
// if it's not a basic code point
if (input.charCodeAt(j) >= 0x80) {
error('not-basic')
}
output.push(input.charCodeAt(j))
}
// Main decoding loop: start just after the last delimiter if any basic code
// points were copied; start at the beginning otherwise.
for (let index = basic > 0 ? basic + 1 : 0; index < inputLength /* no final expression */; ) {
// `index` is the index of the next character to be consumed.
// Decode a generalized variable-length integer into `delta`,
// which gets added to `i`. The overflow checking is easier
// if we increase `i` as we go, then subtract off its starting
// value at the end to obtain `delta`.
let oldi = i
for (let w = 1, k = base /* no condition */; ; k += base) {
if (index >= inputLength) {
error('invalid-input')
}
const digit = basicToDigit(input.charCodeAt(index++))
if (digit >= base || digit > floor((maxInt - i) / w)) {
error('overflow')
}
i += digit * w
const t = k <= bias ? tMin : k >= bias + tMax ? tMax : k - bias
if (digit < t) {
break
}
const baseMinusT = base - t
if (w > floor(maxInt / baseMinusT)) {
error('overflow')
}
w *= baseMinusT
}
const out = output.length + 1
bias = adapt(i - oldi, out, oldi == 0)
// `i` was supposed to wrap around from `out` to `0`,
// incrementing `n` each time, so we'll fix that now:
if (floor(i / out) > maxInt - n) {
error('overflow')
}
n += floor(i / out)
i %= out
// Insert `n` at position `i` of the output.
output.splice(i++, 0, n)
}
return String.fromCodePoint(...output)
}
/**
* Converts a string of Unicode symbols (e.g. a domain name label) to a
* Punycode string of ASCII-only symbols.
* @memberOf punycode
* @param {String} input The string of Unicode symbols.
* @returns {String} The resulting Punycode string of ASCII-only symbols.
*/
const encode = function (input) {
const output = []
// Convert the input in UCS-2 to an array of Unicode code points.
input = ucs2decode(input)
// Cache the length.
let inputLength = input.length
// Initialize the state.
let n = initialN
let delta = 0
let bias = initialBias
// Handle the basic code points.
for (const currentValue of input) {
if (currentValue < 0x80) {
output.push(stringFromCharCode(currentValue))
}
}
let basicLength = output.length
let handledCPCount = basicLength
// `handledCPCount` is the number of code points that have been handled;
// `basicLength` is the number of basic code points.
// Finish the basic string with a delimiter unless it's empty.
if (basicLength) {
output.push(delimiter)
}
// Main encoding loop:
while (handledCPCount < inputLength) {
// All non-basic code points < n have been handled already. Find the next
// larger one:
let m = maxInt
for (const currentValue of input) {
if (currentValue >= n && currentValue < m) {
m = currentValue
}
}
// Increase `delta` enough to advance the decoder's <n,i> state to <m,0>,
// but guard against overflow.
const handledCPCountPlusOne = handledCPCount + 1
if (m - n > floor((maxInt - delta) / handledCPCountPlusOne)) {
error('overflow')
}
delta += (m - n) * handledCPCountPlusOne
n = m
for (const currentValue of input) {
if (currentValue < n && ++delta > maxInt) {
error('overflow')
}
if (currentValue == n) {
// Represent delta as a generalized variable-length integer.
let q = delta
for (let k = base /* no condition */; ; k += base) {
const t = k <= bias ? tMin : k >= bias + tMax ? tMax : k - bias
if (q < t) {
break
}
const qMinusT = q - t
const baseMinusT = base - t
output.push(stringFromCharCode(digitToBasic(t + (qMinusT % baseMinusT), 0)))
q = floor(qMinusT / baseMinusT)
}
output.push(stringFromCharCode(digitToBasic(q, 0)))
bias = adapt(delta, handledCPCountPlusOne, handledCPCount == basicLength)
delta = 0
++handledCPCount
}
}
++delta
++n
}
return output.join('')
}
/**
* Converts a Punycode string representing a domain name or an email address
* to Unicode. Only the Punycoded parts of the input will be converted, i.e.
* it doesn't matter if you call it on a string that has already been
* converted to Unicode.
* @memberOf punycode
* @param {String} input The Punycoded domain name or email address to
* convert to Unicode.
* @returns {String} The Unicode representation of the given Punycode
* string.
*/
const toUnicode = function (input) {
return mapDomain(input, function (string) {
return regexPunycode.test(string) ? decode(string.slice(4).toLowerCase()) : string
})
}
/**
* Converts a Unicode string representing a domain name or an email address to
* Punycode. Only the non-ASCII parts of the domain name will be converted,
* i.e. it doesn't matter if you call it with a domain that's already in
* ASCII.
* @memberOf punycode
* @param {String} input The domain name or email address to convert, as a
* Unicode string.
* @returns {String} The Punycode representation of the given domain name or
* email address.
*/
const toASCII = function (input) {
return mapDomain(input, function (string) {
return regexNonASCII.test(string) ? 'xn--' + encode(string) : string
})
}
/*--------------------------------------------------------------------------*/
/** Define the public API */
const punycode = {
/**
* A string representing the current Punycode.js version number.
* @memberOf punycode
* @type String
*/
version: '2.1.0',
/**
* An object of methods to convert from JavaScript's internal character
* representation (UCS-2) to Unicode code points, and back.
* @see <https://mathiasbynens.be/notes/javascript-encoding>
* @memberOf punycode
* @type Object
*/
ucs2: {
decode: ucs2decode,
encode: ucs2encode
},
decode: decode,
encode: encode,
toASCII: toASCII,
toUnicode: toUnicode
}
module.exports = punycode