// blur.js

var blur = new _blur();

function _blur() {
	var blur = new Object();
	
	this.initialise = initialise;
	this.start = start;
	this.stop = stop;
	this.animate = animate;
	
	function initialise(parameters) {
		var image = document.images[parameters["image"]];
		var imageLeft = 0, imageTop = 0, imageWidth = 0, imageHeight = 0;
		try {
			imageWidth = image.offsetWidth;
			imageHeight = image.offsetHeight;
			imageLeft = image.offsetLeft;
			imageTop = image.offsetTop;
			while(image.offsetParent) {
				imageLeft += image.offsetParent.offsetLeft;
				imageTop += image.offsetParent.offsetTop;
				image = image.offsetParent;
			}
		} catch(e) {}
				
		for (var i in parameters["blur"]) {
			blur[i] = new __blur();	
			blur[i].initialise({id: i, left: imageLeft, top: imageTop, width: imageWidth, height: imageHeight, blur: parameters["blur"][i]});	
		}	
	}
	
	function start() {
		for (var i in blur) {
			blur[i].start();	
		}
	}
	
	function stop() {
		for (var i in blur) {
			blur[i].stop();	
		}
	}
	
	function animate(id) {
		blur[id].animate();
	}
	
	function __blur() {
		var _timer, _interval, _index, _style, _frames, _id, _div; 
	
		this.initialise = initialise;
		this.start = start;
		this.stop = stop;
		this.animate = animate;
		
		function initialise(parameters) {
			var blurParameters = parameters["blur"];
			
			_id = parameters["id"];
			_interval = Math.ceil(1000 / blurParameters["framesPerSecond"]);
			_frames = Math.ceil(blurParameters["time"] / 1000 * blurParameters["framesPerSecond"]);
			_style = new Array(_frames);
			for (var i = 0; i < _frames; i++) {
				_style[i] = new Object();
			}
			
			var startLeft = blurParameters["startLeft"] * parameters["width"] / 100 + parameters["left"];
			var endLeft = blurParameters["endLeft"] * parameters["width"] / 100 + parameters["left"];
			switch(blurParameters["calcLeft"]) {
				case "linear": linear("left", startLeft, endLeft - startLeft, _frames); break;
					
				default:
					break;	
			}
			for (var i = 0; i < _frames; i++) {
				_style[i]["left"] = Math.min(Math.ceil(_style[i]["left"]), parameters["left"] + parameters["width"]) + "px";
			}
			
			var startWidth = blurParameters["startWidth"] * parameters["width"] / 100;
			var endWidth = blurParameters["endWidth"] * parameters["width"] / 100;
			switch(blurParameters["calcWidth"]) {
				case "linear": linear("width", startWidth, endWidth - startWidth, _frames); break;
					
				default:
					break;	
			}
			for (var i = 0; i < _frames; i++) {
				_style[i]["width"] = Math.ceil(Math.min(_style[i]["width"], parameters["left"] + parameters["width"] - parseInt(_style[i]["left"], 10))) + "px";
			}
			
			switch(blurParameters["calcOpacity"]) {
				case "linear": linear("opacity", blurParameters["startOpacity"], blurParameters["endOpacity"] - blurParameters["startOpacity"], _frames); break;
					
				default:
					break;	
			}
			for (var i = 0; i < _frames; i++) {
				_style[i]["-moz-opacity"] = _style[i]["opacity"];
				_style[i]["filter"] = "alpha(opacity=" + Math.ceil(100 * _style[i]["opacity"]) + ")";
			}

			_style[0]["display"] = "block";
			_style[0]["height"] = parameters["height"];
			_style[0]["top"] = parameters["top"];
			_style[_frames - 1]["display"] = "none";
			
			
			_div = document.createElement("DIV");
			_div.className = "blur";
			document.getElementsByTagName("BODY")[0].appendChild(_div);
		}
		
		function linear(style, start, move, steps) {
			for (var i = 0; i < steps; i++) {
				_style[i][style] = move * i / steps + start;
			}	
		}
		
		function start() {
			_index = 0;
			animate();		
		}
		
		function stop() {
			clearTimeout(_timer);
			_index = _frames - 1;
			animate();
		}
		
		function animate() {
			for (style in _style[_index]) {
				_div.style[style] = _style[_index][style];
			}
			_index++;
			if (_index < _frames) {
				_timer = setTimeout("blur.animate(" + _id + ");", _interval);
			}
		}
		
		return this;
	}
	
	return this;
}