/**
 * Copyright (c) 2009 Sergiy Kovalchuk (serg472@gmail.com)
 * 
 * Dual licensed under the MIT (http://www.opensource.org/licenses/mit-license.php)
 * and GPL (http://www.opensource.org/licenses/gpl-license.php) licenses.
 *  
 * Following code is based on Element.mask() implementation from ExtJS framework (http://extjs.com/)
 *
 */
;(function($){
	
	/**
	 * Displays loading mask over selected element.
	 *
	 * @param label Text message that will be displayed on the top of a mask besides a spinner (optional). 
	 * 				If not provided only mask will be displayed without a label or a spinner.  	
	 */
	$.fn.mask = function(label){
		
		this.unmask();
		
		if(this.css("position") == "static") {
			this.addClass("masked-relative");
		}
		
		this.addClass("masked");
		
		var maskDiv = $('<div class="loadmask"></div>');
		
		//auto height fix for IE
		var ua = navigator.userAgent.toLowerCase();
		var isStrict = document.compatMode == "CSS1Compat";
		var isIE = ua.indexOf("msie") > -1;
		var isIE7 = ua.indexOf("msie 7");
		
		if(isIE && !(isIE7 && isStrict) && this.css("height") == "auto"){ 
			maskDiv.height(this.height());
			maskDiv.width(this.width());
		}
		
		//Modified code 
		//When div'got a scroll bar, height needs to be adjusted
		maskDiv.height(this[0].scrollHeight);
		scrollTop = this[0].scrollTop;
		height = this.height();
		//See if the loading screen is in the content window
		if (window.name == 'iframe_content'){
			 frame = parent.document.getElementById(window.name);
			 scrollTop = window.scrollY; 
			 
			 if (document.documentElement && !document.documentElement.scrollTop){
				// IE6 +4.01 but no scrolling going on
				scrollTop = document.documentElement.scrollTop;
			 }else if (document.documentElement && document.documentElement.scrollTop){
			 	// IE6 +4.01 and user has scrolled    
			 	scrollTop = document.documentElement.scrollTop;     
			 }else if (document.body && document.body.scrollTop){
			 	// IE5 or DTD 3.2
			 	scrollTop = document.body.scrollTop; 
			 }
			
					 
			 if (window.innerWidth) {
			 	height = window.innerHeight;
			}
			else if (document.documentElement && document.documentElement.clientHeight) {
			    height = document.documentElement.clientHeight;
			}
			else if (document.body) {
			    height = document.body.clientHeight;
			}
		}
		
		this.append(maskDiv);
		
		if(typeof label == "string") {
			var maskMsgDiv = $('<div class="loadmask-msg" style="display:none;"></div>');
			maskMsgDiv.append('<div>' + label + '</div>');
			this.append(maskMsgDiv);
			
			//calculate center position
			//Modified code
			//if div height's got scroll bar add the scroll top height to the height in order to push the msg.
			if (scrollTop > 0){
				maskMsgDiv.css("top", Math.round(height / 2 - maskMsgDiv.height() / 2 + scrollTop)+"px");
			}else{
				maskMsgDiv.css("top", Math.round(height / 2 - maskMsgDiv.height() / 2)+"px");
			}
			maskMsgDiv.css("left", Math.round(this.width() / 2 - maskMsgDiv.width() / 2)+"px");
			
			maskMsgDiv.show();
		}
		
	};
	/**
	 * Removes mask from the element.
	 */
	$.fn.unmask = function(label){
		this.find(".loadmask-msg,.loadmask").remove();
		this.removeClass("masked");
		this.removeClass("masked-relative");
	};
 
})(jQuery);