window.addEvent('domready', function() {

	//first remove no-JS background image
	if (browserVersion == "ie6"){
		// -> for IE6
		$(document.body).setStyle('background-image','none');
	}
	else{
		// -> for everything except IE6
		$('background').setStyle('background-image','none');	
	}
	
	//load and fade background image
	//load_image(get_image_by_hour());
	setTimeout("load_image(get_image_by_hour())",250);
});


//decide which image should be loaded
function get_image_by_hour(){
	
	// decide by hour
	var date = new Date();  var hour = date.getHours();
	if (hour > 5 && hour < 10) {
		var img = backimage_morning; 
	}
	if (hour > 9 && hour < 17) {
		var img = backimage_noon; 
	}
	if (hour > 16 && hour < 21) {
		var img = backimage_evening; 
	}
	if (hour < 6 || hour > 20) {
		var img = backimage_night; 
	}
	
	// if there is no image available for this interval: use default
	if(typeof(img) !== 'undefined' && img != null) {
		return img;
	}
	else {
		return backimage_default;
	}
}

//load and fade the background image
function load_image(img_src){
	var image = new Image();
	image.onload = function() {
		
		if (browserVersion == "ie6"){
			// -> for IE6
			var e = $(document.body);
			e.setStyle('background-image','url(' + this.src + ')');
		}
		else{
			// -> for everything except IE6
			var e = $('background');	
		
			e.setStyle('background-image','url(' + this.src + ')');
			e.setStyle('opacity','0.001');
			
			e.fx = new Fx.Styles(e, {duration:1600, wait:false});
			e.fx.start({
					'opacity': 1
			});
		}
	};
	image.src =img_src;

	
}