/*
 * Image Centering
 * Copyright 2009 Drew Wilson
 * www.drewwilson.com
 *
 * Version 1.0   -   Updated: Oct. 10, 2009
 *
 * This Plug-In will center images inside of it's parent element.
 * By default it even scales each image up or down to fit inside it's parent element.
 * It will also wait to make sure each image is loaded before doing any re-sizing.
 *
 * This Image Centering jQuery plug-in is dual licensed under the MIT and GPL licenses:
 *   http://www.opensource.org/licenses/mit-license.php
 *   http://www.gnu.org/licenses/gpl.html
 */

(function($){
	$.fn.imgCenter = function(options) {

		var defaults = {  
		  	parentSteps: 0,
		  	scaleToFit: true,
		  	centerVertical: true,
		  	complete: function(){},
		  	start: function(){},
		  	end: function(){}
	  	};  
	 	var opts = $.extend(defaults, options);
	 	
		opts.start.call(this);
		
		// Get total number of items.
		var len = this.length - 1;
		
		return this.each(function(i){
			var current = i;
			
			// Declare the current Image as a variable.
			var org_image = $(this);
			
			org_image.hide();
			
			// Move up Parents until the spcified limit has been met.
			var theParent = org_image;
			for (var i=0; i <= opts.parentSteps; i++){
				theParent = theParent.parent();
			}			
			var parWidth = parseInt(theParent.width());
			var parHeight = parseInt(theParent.height());
			var parAspect = parWidth / parHeight;

			if(org_image[0].complete){
				imgMath(org_image);
			} else {
				var loadWatch = setInterval(watch, 500);
			}
			
			function watch(){
				if(org_image[0].complete){
					clearInterval(loadWatch);
					imgMath(org_image);
				}
			}

			function imgMath(org_image) {
				// Get image properties.		
				var imgWidth = parseInt(org_image.width());
				var imgHeight = parseInt(org_image.height());
				var imgAspect = imgWidth / imgHeight;
	
				// Center the image.
				if(parWidth != imgWidth || parHeight != imgHeight){
					theParent.css("overflow","hidden");
					
					if(opts.scaleToFit){
						if(parAspect >= 1){
							org_image.css({"width": parWidth +"px"});
							imgWidth = parWidth;
							imgHeight = Math.round(imgWidth / imgAspect);
							
							if((parWidth / imgAspect) < parHeight){
								org_image.css({"height": parHeight +"px","width":"auto"});
								imgHeight = parHeight;
								imgWidth = Math.round(imgHeight * imgAspect);
							}				
						} else {
							org_image.css({"height": parHeight +"px"});
							imgHeight = parHeight;
							imgWidth = Math.round(imgHeight * imgAspect);
							if((parHeight * imgAspect) < parWidth){
								org_image.css({"width": parWidth +"px","height":"auto"});
								imgWidth = parWidth;
								imgHeight = Math.round(imgWidth / imgAspect);
							}
						}
						if(imgWidth > parWidth){
							org_image.css({"margin-left":"-"+ Math.round((imgWidth - parWidth) / 2) +"px"});
						}
						if(imgHeight > parHeight && opts.centerVertical){
							org_image.css({"margin-top":"-"+ Math.round((imgHeight - parHeight) / 2) +"px"});
						}		
					} else {
						if(imgWidth > parWidth){
							org_image.css({"margin-left":"-"+ Math.round((imgWidth - parWidth) / 2) +"px"});
						} else if(imgWidth < parWidth){
							org_image.css({"margin-left": Math.round((parWidth - imgWidth) / 2) +"px"});
						}
						if(imgHeight > parHeight && opts.centerVertical){
							org_image.css({"margin-top":"-"+ Math.round((imgHeight - parHeight) / 2) +"px"});
						} else if(imgHeight < parHeight && opts.centerVertical){
							org_image.css({"margin-top": Math.round((parHeight - imgHeight) / 2) +"px"});
						}
					}
					opts.complete.call(this);
					if(current == len){
						opts.end.call(this);
					}
				}
				org_image.show();	
			}
			
		});		
	}
})(jQuery);