/**
 * jQuery-Plugin "preloadCssImages"
 * by Scott Jehl, scott@filamentgroup.com
 * http://www.filamentgroup.com
 * reference article: http://www.filamentgroup.com/lab/update_automatically_preload_images_from_css_with_jquery/
 * demo page: http://www.filamentgroup.com/examples/preloadImages/index_v2.php
 * 
 * Copyright (c) 2008 Filament Group, Inc
 * Dual licensed under the MIT (filamentgroup.com/examples/mit-license.txt) and GPL (filamentgroup.com/examples/gpl-license.txt) licenses.
 *
 * Version: 5.0, 10.31.2008
 * Changelog:
 * 	02.20.2008 initial Version 1.0
 *    06.04.2008 Version 2.0 : removed need for any passed arguments. Images load from any and all directories.
 *    06.21.2008 Version 3.0 : Added options for loading status. Fixed IE abs image path bug (thanks Sam Pohlenz).
 *    07.24.2008 Version 4.0 : Added support for @imported CSS (credit: http://marcarea.com/). Fixed support in Opera as well. 
 *    10.31.2008 Version: 5.0 : Many feature and performance enhancements from trixta
 * --------------------------------------------------------------------
 */

;jQuery.preloadCssImages = function(settings){
	settings = jQuery.extend({
		statusTextEl: null,
		statusBarEl: null,
		errorDelay: 999, // handles 404-Errors in IE
		simultaneousCacheLoading: 2
	}, settings);
	var allImgs = [],
		loaded = 0,
		imgUrls = [],
		thisSheetRules,	
		errorTimer;
	
	function onImgComplete(){
		clearTimeout(errorTimer);
		if (imgUrls && imgUrls.length && imgUrls[loaded]) {
			loaded++;
			if (settings.statusTextEl) {
				var nowloading = (imgUrls[loaded]) ? 
					'Now Loading: <span>' + imgUrls[loaded].split('/')[imgUrls[loaded].split('/').length - 1] : 
					'Loading complete'; // wrong status-text bug fixed
				jQuery(settings.statusTextEl).html('<span class="numLoaded">' + loaded + '</span> of <span class="numTotal">' + imgUrls.length + '</span> loaded (<span class="percentLoaded">' + (loaded / imgUrls.length * 100).toFixed(0) + '%</span>) <span class="currentImg">' + nowloading + '</span></span>');
			}
			if (settings.statusBarEl) {
				var barWidth = jQuery(settings.statusBarEl).width();
				jQuery(settings.statusBarEl).css('background-position', -(barWidth - (barWidth * loaded / imgUrls.length).toFixed(0)) + 'px 50%');
			}
			loadImgs();
		}
	}
	
	function loadImgs(){
		//only load 1 image at the same time / most browsers can only handle 2 http requests, 1 should remain for user-interaction (Ajax, other images, normal page requests...)
		// otherwise set simultaneousCacheLoading to a higher number for simultaneous downloads
		if(imgUrls && imgUrls.length && imgUrls[loaded]){
			var img = new Image(); //new img obj
			img.src = imgUrls[loaded];	//set src either absolute or rel to css dir
			if(!img.complete){
				jQuery(img).bind('error load onreadystatechange', onImgComplete);
			} else {
				onImgComplete();
			}
			errorTimer = setTimeout(onImgComplete, settings.errorDelay); // handles 404-Errors in IE
		}
	}
	
	function parseCSS(sheets, urls) {
		var w3cImport = false,
			imported = [],
			importedSrc = [],
			baseURL;
		var sheetIndex = sheets.length;
		while(sheetIndex--){//loop through each stylesheet
			
			var cssPile = '';//create large string of all css rules in sheet
			
			if(urls && urls[sheetIndex]){
				baseURL = urls[sheetIndex];
			} else {
				var csshref = (sheets[sheetIndex].href) ? sheets[sheetIndex].href : 'window.location.href';
				var baseURLarr = csshref.split('/');//split href at / to make array
				baseURLarr.pop();//remove file path from baseURL array
				baseURL = baseURLarr.join('/');//create base url for the images in this sheet (css file's dir)
				if (baseURL) {
					baseURL += '/'; //tack on a / if needed
				}
			}
			
			if (!csshref.startsWith("file:")) {
			    if(sheets[sheetIndex].cssRules || sheets[sheetIndex].rules){
				    thisSheetRules = (sheets[sheetIndex].cssRules) ? //->>> http://www.quirksmode.org/dom/w3c_css.html
					    sheets[sheetIndex].cssRules : //w3
					    sheets[sheetIndex].rules; //ie 
				    var ruleIndex = thisSheetRules.length;
				    while(ruleIndex--){
					    if(thisSheetRules[ruleIndex].style && thisSheetRules[ruleIndex].style.cssText){
						    var text = thisSheetRules[ruleIndex].style.cssText;
						    if(text.toLowerCase().indexOf('url') != -1){ // only add rules to the string if you can assume, to find an image, speed improvement
							    cssPile += text; // thisSheetRules[ruleIndex].style.cssText instead of thisSheetRules[ruleIndex].cssText is a huge speed improvement
						    }
					    } else if(thisSheetRules[ruleIndex].styleSheet) {
						    imported.push(thisSheetRules[ruleIndex].styleSheet);
						    w3cImport = true;
					    }
    					
				    }
			    }
			}
			
			//parse cssPile for image urls
			var tmpImage = cssPile.match(/[^\("]+\.(gif|jpg|jpeg|png)/gi);//reg ex to get a string of between a "(" and a ".filename" / '"' for opera-bugfix
			if(tmpImage){
				var i = tmpImage.length;
				while(i--){ // handle baseUrl here for multiple stylesheets in different folders bug
					var imgSrc = (tmpImage[i].charAt(0) == '/' || tmpImage[i].match('://')) ? // protocol-bug fixed
						tmpImage[i] : 
						baseURL + tmpImage[i];
					
					if(jQuery.inArray(imgSrc, imgUrls) == -1){
						imgUrls.push(imgSrc);
					}
				}
			}
			
			if(!w3cImport && sheets[sheetIndex].imports && sheets[sheetIndex].imports.length) {
				for(var iImport = 0, importLen = sheets[sheetIndex].imports.length; iImport < importLen; iImport++){
					var iHref = sheets[sheetIndex].imports[iImport].href;
					iHref = iHref.split('/');
					iHref.pop();
					iHref = iHref.join('/');
					if (iHref) {
						iHref += '/'; //tack on a / if needed
					}
					var iSrc = (iHref.charAt(0) == '/' || iHref.match('://')) ? // protocol-bug fixed
						iHref : 
						baseURL + iHref;
					
					importedSrc.push(iSrc);
					imported.push(sheets[sheetIndex].imports[iImport]);
				}
				
				
			}
		}//loop
		if(imported.length){
			parseCSS(imported, importedSrc);
			return false;
		}
		var downloads = settings.simultaneousCacheLoading;
		while( downloads--){
			setTimeout(loadImgs, downloads);
		}
	}
	parseCSS(document.styleSheets);
	return imgUrls;
};






















///**
// * --------------------------------------------------------------------
// * jQuery-Plugin "preloadCssImages"
// * by Scott Jehl, scott@filamentgroup.com
// * http://www.filamentgroup.com
// * reference article: http://www.filamentgroup.com/lab/update_automatically_preload_images_from_css_with_jquery/
// * demo page: http://www.filamentgroup.com/examples/preloadImages/index_v4.php
// * 
// * Copyright (c) 2008 Filament Group, Inc
// * Dual licensed under the MIT (filamentgroup.com/examples/mit-license.txt) and GPL (filamentgroup.com/examples/gpl-license.txt) licenses.
// *
// * Version: 4.0, 07.24.2008
// * Changelog:
// * 	02.20.2008 initial Version 1.0
// *    06.04.2008 Version 2.0 : removed need for any passed arguments. Images load from any and all directories.
// *    06.21.2008 Version 3.0 : Added options for loading status. Fixed IE abs image path bug (thanks Sam Pohlenz).
// *    07.24.2008 Version 4.0 : Added support for @imported CSS (credit: http://marcarea.com/). Fixed support in Opera as well.
// * --------------------------------------------------------------------
// */
//jQuery.preloadCssImages = function(settings){
//	var settings = jQuery.extend({
//		statusTextEl: null,
//		statusBarEl: null
//	}, settings);
//	
//	var allImgs = [];//new array for all the image urls  
//	var k = 0; //iterator for adding images
//	var sheets = document.styleSheets;//array of stylesheets
//	
//	for(var i = 0; i<sheets.length; i++){//loop through each stylesheet
//		var cssPile = '';//create large string of all css rules in sheet
//		var csshref = (sheets[i].href) ? sheets[i].href : 'window.location.href';
//		var baseURLarr = csshref.split('/');//split href at / to make array
//		baseURLarr.pop();//remove file path from baseURL array
//		var baseURL = baseURLarr.join('/');//create base url for the images in this sheet (css file's dir)
//		if(baseURL!="") baseURL+='/'; //tack on a / if needed
//		if(sheets[i].cssRules){//w3 
//			var thisSheetRules = sheets[i].cssRules; //w3 
//			for(var j = 0; j<thisSheetRules.length; j++){ 
//				if ( sheets[i].cssRules[j].constructor == 'CSSImportRule' ) { //added support for @imported css - credit: http://marcarea.com/
//					var importSheetRules = sheets[i].cssRules[j].styleSheet.cssRules; 
//					for ( var x=0; x<importSheetRules.length; x++ ) { 
//						cssPile+= importSheetRules[x].cssText; 
//					} 
//				} 
//				else { 
//					cssPile+= thisSheetRules[j].cssText; 
//				} 
//			} 
//		} 
//		else { 
//			if ( sheets[i].imports.length > 0 ) { 
//				for (var m=0; m<sheets[i].imports.length; m++) { 
//					cssPile+= sheets[i].imports[m].cssText;
//				} 
//			} 
//			else { 
//				cssPile+= sheets[i].cssText; 
//			} 
//		}
//		
//		//parse cssPile for image urls and load them into the DOM
//		var imgUrls = cssPile.match(/[^\(]+\.(gif|jpg|jpeg|png)/gi);//reg ex to get a string of between a "(" and a ".filename"
//		//var loaded = 0; //number of images loaded

//		if(imgUrls != null && imgUrls.length>0 && imgUrls != ''){//loop array\
//			var arr = jQuery.makeArray(imgUrls);//create array from regex obj	 
//			jQuery(arr).each(function(){
//				
//				allImgs[k] = new Image(); //new img obj
//				allImgs[k].src = (this.charAt(0) == '/' || this.indexOf('http://')>-1) ? this : baseURL + this;	//set src either absolute or rel to css dir
//				
//				if(allImgs[k].src.lastIndexOf('http://')>0){allImgs[k].src = allImgs[k].src.split('%22')[1];} //fixed opera's source doubling
//				
//				window.status = "Loading image : " + allImgs[k].src ;
//				
////				jQuery(allImgs[k]).load(function(){
////					loaded++;
////					//send updates to status elements if applicable
////					if(settings.statusTextEl) {
////						jQuery(settings.statusTextEl).html('<span class="numLoaded">'+loaded+'</span> of <span class="numTotal">'+allImgs.length+'</span> loaded (<span class="percentLoaded">'+(loaded/allImgs.length*100).toFixed(0)+'%</span>) <span class="currentImg">Now Loading: <span>'+allImgs[loaded-1].src.split('/')[allImgs[loaded-1].src.split('/').length-1]+'</span></span>');
////					}
////					if(settings.statusBarEl) {
////						var barWidth = jQuery(settings.statusBarEl).width();
////						jQuery(settings.statusBarEl).css('background-position', -(barWidth-(barWidth*loaded/allImgs.length).toFixed(0))+'px 50%');
////					}
////				});

//				k++;
//			});
//		}
//	}//loop
//	return allImgs;
//}				
//