Credit Card Generator

//
// Random Credit Card Number Generator
//
// By: Brad Conte (http://bradconte.com)
//

function cc_gen() {
	var pos = 12;
	var str = new Array(7,8,2,4,6,7,0,2,0,0,0,0,5,4,5,3,3,6,1);
	var sum = 0;
	var final_digit = 0;
	var t = 0;
	var len_offset = 0;
	var len = 19;
	var issuer;


	//
	// Fill all the remaining numbers except for the last one with random values.
	//

	while (pos < len - 1) {
		str[pos++] = Math.floor(Math.random() * 10) % 10;
	}

	//
	// Calculate the Luhn checksum of the values thus far.
	//

	len_offset = (len + 1) % 2;
	for (pos = 0; pos < len - 1; pos++) {
		if ((pos + len_offset) % 2) {
			t = str[pos] * 2;
			if (t > 9) {
				t -= 9;
			}
			sum += t;
		}
		else {
			sum += str[pos];
		}
	}

	//
	// Choose the last digit so that it causes the entire string to pass the checksum.
	//

	final_digit = (10 - (sum % 10)) % 10;
	str[len - 1] = final_digit;

	// Output the CC value.
	t = str.join('');
	t = t.substr(0, len);
	console.log(t);
}