(function($) {
	
	$.fn.shadowenable  = function() { return $(this).find("+ .fx-shadow").show().end();   };
	$.fn.shadowdisable = function() { return $(this).find("+ .fx-shadow").hide().end();   };
	$.fn.shadowdestroy = function() { return $(this).find("+ .fx-shadow").remove().end(); };
	
	$.fn.shadow = function(options) {
		options = $.extend({
			offset:  1,
			opacity: 0.2,
			color:   "#000",
			monitor: false
		}, options || {});
		options.offset -= 1;
		
		return this.each(function() {
			
			// remove an existing shadow if it exists
			var $element = $(this).shadowdestroy(),
			
			// create a shadow element
			$shadow = $("<div class='fx-shadow' style='position: relative;'></div>").hide().insertafter($element);
			
			// figure the base height and width
			basewidth  = $element.outerwidth(),
			baseheight = $element.outerheight(),
			
			// get the offset
			position = $element.position(),
			
			// get z-index
			zindex = parseint($element.css("zindex")) || 0;
			
			// append smooth corners
			$('<div class="fx-shadow-color fx-shadow-layer-1"></div>').css({ position: 'absolute', opacity: options.opacity - 0.05,  left: options.offset,     top: options.offset,     width: basewidth + 1, height: baseheight + 1 }).appendto($shadow);
			$('<div class="fx-shadow-color fx-shadow-layer-2"></div>').css({ position: 'absolute', opacity: options.opacity - 0.10,  left: options.offset + 2, top: options.offset + 2, width: basewidth,     height: baseheight - 3 }).appendto($shadow);
			$('<div class="fx-shadow-color fx-shadow-layer-3"></div>').css({ position: 'absolute', opacity: options.opacity - 0.10,  left: options.offset + 2, top: options.offset + 2, width: basewidth - 3, height: baseheight     }).appendto($shadow);
			$('<div class="fx-shadow-color fx-shadow-layer-4"></div>').css({ position: 'absolute', opacity: options.opacity,         left: options.offset + 1, top: options.offset + 1, width: basewidth - 1, height: baseheight - 1 }).appendto($shadow);
			
			// add color
			$("div.fx-shadow-color", $shadow).css("background-color", options.color);
			
			// set zindex +1 and make sure position is at least relative
			// attention: the zindex will get one higher!
			$element
				.css({
					zindex: zindex + 1,
					position: ($element.css("position") == "static" ? "relative" : "")
				});
			
			// copy the original z-index and position to the clone
			// alert(shadow); if you insert this alert, opera will time correctly!!
			$shadow.css({
				position:     "absolute",
				zindex:       zindex,
				top:          position.top+"px",
				left:         position.left+"px",
				width:        basewidth,
				height:       baseheight,
				marginleft:   $element.css("marginleft"),
				marginright:  $element.css("marginright"),
				marginbottom: $element.css("marginbottom"),
				margintop:    $element.css("margintop")
			}).fadein();
			
			
			if ( options.monitor ) {
				function rearrangeshadow() {
					var $element = $(this), $shadow = $element.next();
					// $shadow.css( $element.position() );
					$shadow.css({
						top:  parseint($element.css("top"))  +"px",
						left: parseint($element.css("left")) +"px"
					})
					$(">*", $shadow).css({ height: this.offsetheight+"px", width: this.offsetwidth+"px" });
				}
			
				// attempt to use domattrmodified event
				$element.bind("domattrmodified", rearrangeshadow);
			
				// use expressions if they exist (ie)
				if( $shadow[0].style.setexpression ) {
					$shadow[0].style.setexpression("top" , "parseint(this.previoussibling.currentstyle.top ) + 'px'");
					$shadow[0].style.setexpression("left", "parseint(this.previoussibling.currentstyle.left) + 'px'");
				}
			}

		});
	};
	
})(jquery);