function initDiscCalc(qty, id, cartvalue) {
	$.ajax({
		dataType: 'jsonp',
		data: {prodQty: qty, prodID: id},
		jsonp: 'callback',
		url: 'http://www.littlebrowndogltd.co.uk/EKMScripts/disccalc.php',
		error: function() {
			//alert("Error");	
		}
	});
	if (cartvalue) {
		$('#cartTotal').text(cartvalue);
	}
}
function callback(data) {
	var completeDVDs = data[0];
	var leftOnThisDisc = data[1];
	var leftOnThisDiscMb = (leftOnThisDisc * 1000).toFixed(2);
	var currentDVD = data[2];
	if (currentDVD < 1){
		$('#numberofDiscs').text('Current Playlist Value');
	} else if (currentDVD == 1) {
		$('#numberofDiscs').text("You've used "+currentDVD+" disc");
	} else {
		$('#numberofDiscs').text("You've used "+currentDVD+" discs");
	}
		
	if (currentDVD < 1) {
		$('#availableSpace').text('0.00Gb');
		$('#availableSpace').css('color', '#54BF4C');
	} else {
		if (leftOnThisDiscMb > 1024) {
			$('#availableSpace').text(leftOnThisDisc.toFixed(2)+'Gb');
			$('#availableSpace').css('color', '#54BF4C');
		} else {
			leftOnThisDiscMb = parseInt(leftOnThisDiscMb);
			
			if (leftOnThisDiscMb < 250 && leftOnThisDisc > 0.01) {
				$('#availableSpace').text(leftOnThisDiscMb.toFixed(2)+'Mb');
				$('#availableSpace').css('color', '#ff0000');
			} else {
				$('#availableSpace').text(leftOnThisDisc.toFixed(2)+'Gb');
				$('#availableSpace').css('color', '#54BF4C');
			}
		}
	}
}