visjs-network
Version:
A dynamic, browser-based network visualization library.
244 lines (197 loc) • 6.12 kB
JavaScript
/* eslint-disable require-jsdoc */
var _rng
var globalVar =
typeof window !== 'undefined'
? window
: typeof global !== 'undefined'
? global
: null
if (globalVar && globalVar.crypto && crypto.getRandomValues) {
// WHATWG crypto-based RNG - http://wiki.whatwg.org/wiki/Crypto
// Moderately fast, high quality
var _rnds8 = new Uint8Array(16)
_rng = function whatwgRNG() {
crypto.getRandomValues(_rnds8)
return _rnds8
}
}
if (!_rng) {
// Math.random()-based (RNG)
//
// If all else fails, use Math.random(). It's fast, but is of unspecified
// quality.
var _rnds = new Array(16)
_rng = function() {
for (var i = 0, r; i < 16; i++) {
if ((i & 0x03) === 0) r = Math.random() * 0x100000000
_rnds[i] = (r >>> ((i & 0x03) << 3)) & 0xff
}
return _rnds
}
}
// uuid.js
//
// Copyright (c) 2010-2012 Robert Kieffer
// MIT License - http://opensource.org/licenses/mit-license.php
// Unique ID creation requires a high quality random # generator. We feature
// detect to determine the best RNG source, normalizing to a function that
// returns 128-bits of randomness, since that's what's usually required
//var _rng = require('./rng');
// Maps for number <-> hex string conversion
var _byteToHex = []
var _hexToByte = {}
for (var i = 0; i < 256; i++) {
_byteToHex[i] = (i + 0x100).toString(16).substr(1)
_hexToByte[_byteToHex[i]] = i
}
// **`parse()` - Parse a UUID into it's component bytes**
function parse(s, buf, offset) {
var i = (buf && offset) || 0,
ii = 0
buf = buf || []
s.toLowerCase().replace(/[0-9a-f]{2}/g, function(oct) {
if (ii < 16) {
// Don't overflow!
buf[i + ii++] = _hexToByte[oct]
}
})
// Zero out remaining bytes if string was short
while (ii < 16) {
buf[i + ii++] = 0
}
return buf
}
// **`unparse()` - Convert UUID byte array (ala parse()) into a string**
function unparse(buf, offset) {
var i = offset || 0,
bth = _byteToHex
return (
bth[buf[i++]] +
bth[buf[i++]] +
bth[buf[i++]] +
bth[buf[i++]] +
'-' +
bth[buf[i++]] +
bth[buf[i++]] +
'-' +
bth[buf[i++]] +
bth[buf[i++]] +
'-' +
bth[buf[i++]] +
bth[buf[i++]] +
'-' +
bth[buf[i++]] +
bth[buf[i++]] +
bth[buf[i++]] +
bth[buf[i++]] +
bth[buf[i++]] +
bth[buf[i++]]
)
}
// **`v1()` - Generate time-based UUID**
//
// Inspired by https://github.com/LiosK/UUID.js
// and http://docs.python.org/library/uuid.html
// random #'s we need to init node and clockseq
var _seedBytes = _rng()
// Per 4.5, create and 48-bit node id, (47 random bits + multicast bit = 1)
var _nodeId = [
_seedBytes[0] | 0x01,
_seedBytes[1],
_seedBytes[2],
_seedBytes[3],
_seedBytes[4],
_seedBytes[5]
]
// Per 4.2.2, randomize (14 bit) clockseq
var _clockseq = ((_seedBytes[6] << 8) | _seedBytes[7]) & 0x3fff
// Previous uuid creation time
var _lastMSecs = 0,
_lastNSecs = 0
// See https://github.com/broofa/node-uuid for API details
function v1(options, buf, offset) {
var i = (buf && offset) || 0
var b = buf || []
options = options || {}
var clockseq = options.clockseq !== undefined ? options.clockseq : _clockseq
// UUID timestamps are 100 nano-second units since the Gregorian epoch,
// (1582-10-15 00:00). JSNumbers aren't precise enough for this, so
// time is handled internally as 'msecs' (integer milliseconds) and 'nsecs'
// (100-nanoseconds offset from msecs) since unix epoch, 1970-01-01 00:00.
var msecs = options.msecs !== undefined ? options.msecs : new Date().getTime()
// Per 4.2.1.2, use count of uuid's generated during the current clock
// cycle to simulate higher resolution clock
var nsecs = options.nsecs !== undefined ? options.nsecs : _lastNSecs + 1
// Time since last uuid creation (in msecs)
var dt = msecs - _lastMSecs + (nsecs - _lastNSecs) / 10000
// Per 4.2.1.2, Bump clockseq on clock regression
if (dt < 0 && options.clockseq === undefined) {
clockseq = (clockseq + 1) & 0x3fff
}
// Reset nsecs if clock regresses (new clockseq) or we've moved onto a new
// time interval
if ((dt < 0 || msecs > _lastMSecs) && options.nsecs === undefined) {
nsecs = 0
}
// Per 4.2.1.2 Throw error if too many uuids are requested
if (nsecs >= 10000) {
throw new Error("uuid.v1(): Can't create more than 10M uuids/sec")
}
_lastMSecs = msecs
_lastNSecs = nsecs
_clockseq = clockseq
// Per 4.1.4 - Convert from unix epoch to Gregorian epoch
msecs += 12219292800000
// `time_low`
var tl = ((msecs & 0xfffffff) * 10000 + nsecs) % 0x100000000
b[i++] = (tl >>> 24) & 0xff
b[i++] = (tl >>> 16) & 0xff
b[i++] = (tl >>> 8) & 0xff
b[i++] = tl & 0xff
// `time_mid`
var tmh = ((msecs / 0x100000000) * 10000) & 0xfffffff
b[i++] = (tmh >>> 8) & 0xff
b[i++] = tmh & 0xff
// `time_high_and_version`
b[i++] = ((tmh >>> 24) & 0xf) | 0x10 // include version
b[i++] = (tmh >>> 16) & 0xff
// `clock_seq_hi_and_reserved` (Per 4.2.2 - include variant)
b[i++] = (clockseq >>> 8) | 0x80
// `clock_seq_low`
b[i++] = clockseq & 0xff
// `node`
var node = options.node || _nodeId
for (var n = 0; n < 6; n++) {
b[i + n] = node[n]
}
return buf ? buf : unparse(b)
}
// **`v4()` - Generate random UUID**
// See https://github.com/broofa/node-uuid for API details
function v4(options, buf, offset) {
// Deprecated - 'format' argument, as supported in v1.2
var i = (buf && offset) || 0
if (typeof options == 'string') {
buf = options == 'binary' ? new Array(16) : null
options = null
}
options = options || {}
var rnds = options.random || (options.rng || _rng)()
// Per 4.4, set bits for version and `clock_seq_hi_and_reserved`
rnds[6] = (rnds[6] & 0x0f) | 0x40
rnds[8] = (rnds[8] & 0x3f) | 0x80
// Copy bytes to buffer, if provided
if (buf) {
for (var ii = 0; ii < 16; ii++) {
buf[i + ii] = rnds[ii]
}
}
return buf || unparse(rnds)
}
// Export public API
var uuid = v4
uuid.v1 = v1
uuid.v4 = v4
uuid.parse = parse
uuid.unparse = unparse
module.exports = uuid