/**************************************************************

	Script		: Overlay
	Version		: 1.2
	Authors		: Samuel birch
	Desc		: Covers the window with a semi-transparent layer.
	Licence		: Open Source MIT Licence

**************************************************************/

var Overlay = new Class({
	getOptions: function(){
		return {
			colour: '#000',
			opacity: 0.7,
			zIndex: 1,
			container: document.body,
			onClick: Class.empty
		};
	},

	initialize: function(options) {
		this.setOptions(this.getOptions(), options);

		this.options.container = $(this.options.container);

		this.container = new Element('div').setProperty('id', 'OverlayContainer').setStyles({
			position: 'absolute',
			left: '0px',
			top: '0px',
			width: '100%',
			height: '0px',
			zIndex: this.options.zIndex
		}).injectInside(this.options.container);

		this.iframe = new Element('iframe').setProperties({
			'id': 'OverlayIframe',
			'name': 'OverlayIframe',
			'src': 'javascript:void(0);',
			'frameborder': 0,
			'scrolling': 'no'
		}).setStyles({
			'position': 'absolute',
			'top': 0,
			'left': 0,
			'width': '100%',
			'height': '100%',
			'filter': 'progid:DXImageTransform.Microsoft.Alpha(style=0,opacity=0)',
			'opacity': 0,
			'zIndex': 2
		}).injectInside(this.container);

		this.overlay = new Element('div').setProperty('id', 'Overlay').setStyles({
			position: 'absolute',
			left: '0px',
			top: '0px',
			width: '100%',
			height: '100%',
			zIndex: 3,
			backgroundColor: this.options.colour
		}).injectInside(this.container);

		this.container.addEvent('click', function(){
			this.options.onClick();
		}.bind(this));

		this.fade = new Fx.Style(this.container, 'opacity').set(0);
		this.position();

		window.addEvent('resize', this.position.bind(this));
	},

	position: function() { 
		if (this.options.container == document.body) {
			if (!window.ie) {
				this.container.setStyles({top: '0px', height: '0px', left: '0px', width: '0px'});
			}

			if (window.opera) {
				var h = ((window.innerHeight > document.body.clientHeight) ? window.innerHeight : document.body.clientHeight);
			}
			else {
				var h = window.getScrollHeight()+'px';
			}

			if (window.ie) {
				this.container.setStyles({top: '0px', height: h}); 
			}
			else {
				var w = window.getScrollWidth()+'px';

				this.container.setStyles({top: '0px', height: h, left: '0px', width: w});
			}
		}
		else {
			var myCoords = this.options.container.getCoordinates();
			this.container.setStyles({
				top: myCoords.top + 'px',
				height: myCoords.height + 'px',
				left: myCoords.left + 'px',
				width: myCoords.width + 'px'
			});
		}
	},

	show: function(){
		this.fade.start(0, this.options.opacity);
	},

	hide: function(){
		this.fade.start(this.options.opacity, 0);
	}

});

Overlay.implement(new Options);