//Countdown Class by Sean Christmann developer@mustardlab.com
/*
class		CountDown(instancename)
parameters	instancename - the instance of an object loading content, example objects include _root, MovieClip instances, LoadVars instances, etc...
example		mytimer = new CountDown(_root);

method		getSecondsLeft(finishbytes)
parameters	finishbytes - the byte value for when the countdown timer should reach zero, default is getBytesTotal()
returns		the number of seconds left until the specified object has loaded

method		setDefault(char)
parameters	char - a char value to display while the CountDown class spends 1 second determining average loading time, default is "-"
returns		nothing
*/
_global.CountDown = function(obj) {
	this.refobj = obj;
	this.startbytes = this.refobj.getBytesLoaded();
	this.lastbytes = this.refobj.getBytesLoaded();
	this.avgbytes = 0.1;
	this.nullchar = "-";
	this.secs = 0;
	this.runAvg = function() {
		this.secs++;
		this.loadedbytes = this.refobj.getBytesLoaded();
		this.avgbytes = (((this.loadedbytes-this.startbytes)/this.secs)*0.7)+((this.loadedbytes-this.lastbytes)*0.3);
		this.lastbytes = this.loadedbytes;
		if (this.loadedbytes>=this.refobj.getBytesTotal()) clearInterval(this.interv);
	};
	this.interv = setInterval(this, "runAvg", 1000);
};
CountDown.prototype.getSecondsLeft = function(finishbytes) {
	if (!finishbytes.length || finishbytes>this.refobj.getBytesTotal()) var finishbytes = this.refobj.getBytesTotal();
	var secsleft;
	var bytesleft = finishbytes-this.loadedbytes;
	if (this.secs == 0) {
		secsleft = this.nullchar;
	}else if (bytesleft>0) {
		secsleft = Math.ceil(bytesleft/this.avgbytes);		
	} else {
		secsleft = 0;
	}
	return secsleft;
};
CountDown.prototype.setDefault = function(char) {
	this.nullchar = char;
};