pc-component-v5/packages/common/Uuid.js

module.exports = {
	createUUID: function () {
		var _self = this;
		// Loose interpretation of the specification DCE 1.1: Remote Procedure Call
		// since JavaScript doesn't allow access to internal systems, the last 48 bits 
		// of the node section is made up using a series of random numbers (6 octets long).
		//  
		var dg = new Date(1582, 10, 15, 0, 0, 0, 0);
		var dc = new Date();
		var t = dc.getTime() - dg.getTime();
		var tl = _self.getIntegerBits(t, 0, 31);
		var tm = _self.getIntegerBits(t, 32, 47);
		var thv = _self.getIntegerBits(t, 48, 59) + '1'; // version 1, security version is 2
		var csar = _self.getIntegerBits(_self.rand(4095), 0, 7);
		var csl = _self.getIntegerBits(_self.rand(4095), 0, 7);
		// since detection of anything about the machine/browser is far to buggy, 
		// include some more random numbers here
		// if NIC or an IP can be obtained reliably, that should be put in
		// here instead.
		var n = _self.getIntegerBits(_self.rand(8191), 0, 7) +
			_self.getIntegerBits(_self.rand(8191), 8, 15) +
			_self.getIntegerBits(_self.rand(8191), 0, 7) +
			_self.getIntegerBits(_self.rand(8191), 8, 15) +
			_self.getIntegerBits(_self.rand(8191), 0, 15); // this last number is two octets long
		return tl + tm + thv + csar + csl + n;
	},

	//Pull out only certain bits from a very large integer, used to get the time
	//code information for the first part of a UUID. Will return zero's if there 
	//aren't enough bits to shift where it needs to.
	getIntegerBits: function (val, start, end) {
		var base16 = this.returnBase(val, 16);
		var quadArray = new Array();
		var quadString = '';
		var i = 0;
		for (i = 0; i < base16.length; i++) {
			quadArray.push(base16.substring(i, i + 1));
		}
		for (i = Math.floor(start / 4); i <= Math.floor(end / 4); i++) {
			if (!quadArray[i] || quadArray[i] == '')
				quadString += '0';
			else
				quadString += quadArray[i];
		}
		return quadString;
	},

	//Replaced from the original function to leverage the built in methods in
	//JavaScript. Thanks to Robert Kieffer for pointing this one out
	returnBase: function (number, base) {
		return (number).toString(base).toUpperCase();
	},

	//pick a random number within a range of numbers
	//int b rand(int a); where 0 <= b <= a
	rand: function (max) {
		return Math.floor(Math.random() * (max + 1));
	},
}