/**
 * jQuery (PNG Fix) v1.2
 * Microsoft Internet Explorer 24bit PNG Fix
 *
 * The MIT License
 * 
 * Copyright (c) 2007 Paul Campbell (pauljamescampbell.co.uk)
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * @param		Object
 * @return		Array
 */
(function($) {
    
    $.fn.pngfix = function(options) {
	
	// Review the Microsoft IE developer library for AlphaImageLoader reference 
	// http://msdn2.microsoft.com/en-us/library/ms532969(VS.85).aspx
	
	// ECMA scope fix
	var elements 	= this;
	var settings 	= $.extend({
	    imageFixSrc: 	false,
	    sizingMethod: 	false 
	}, options);
	
	if(!$.browser.msie || ($.browser.msie &&  $.browser.version >= 7)) {
	    return(elements);
	}

	function setFilter(el, path, mode) {
	    var fs = el.attr("filters");
	    var alpha = "DXImageTransform.Microsoft.AlphaImageLoader";
	    if (fs[alpha]) {
		fs[alpha].enabled = true;
		fs[alpha].src = path; 
		fs[alpha].sizingMethod = mode;
	    } else {
		el.css("filter", 'progid:' + alpha + '(enabled="true", sizingMethod="' + mode + '", src="' + path + '")');			
	    }
	}
	
	function setDOMElementWidth(el) {
	    if(el.css("width") == "auto" & el.css("height") == "auto") {
		el.css("width", el.attr("offsetWidth") + "px");
	    }
	}

	return(
	    elements.each(function() {
		
		// Scope
		var el = $(this);
		
		if(el.attr("tagName").toUpperCase() == "IMG" && (/\.png/i).test(el.attr("src"))) {
		    if(!settings.imageFixSrc) {
			
			// Wrap the <img> in a <span> then apply style/filters, 
			// removing the <img> tag from the final render 
			el.wrap("<span></span>");
			var par = el.parent();
			par.css({
			    height: 	el.height(),
			    width: 		el.width(),
			    display: 	"inline-block"
			});
			setFilter(par, el.attr("src"), "scale");
			el.remove();
		    } else if((/\.gif/i).test(settings.imageFixSrc)) {
			
			// Replace the current image with a transparent GIF
			// and apply the filter to the background of the 
			// <img> tag (not the preferred route)
			setDOMElementWidth(el);
			setFilter(el, el.attr("src"), "image");
			el.attr("src", settings.imageFixSrc);
		    }
		    
		} else {
		    var bg = new String(el.css("backgroundImage"));
		    var matches = bg.match(/^url\("(.*)"\)$/);
		    if(matches && matches.length) {
			
			// Elements with a PNG as a backgroundImage have the
			// filter applied with a sizing method relevant to the 
			// background repeat type
			setDOMElementWidth(el);
			el.css("backgroundImage", "none");
			
			// Restrict scaling methods to valid MSDN defintions (or one custom)
			var sc = "crop";
			if(settings.sizingMethod) {
			    sc = settings.sizingMethod;
			} 
			setFilter(el, matches[1], sc);
			
			// Fix IE peek-a-boo bug for internal links
			// within that DOM element
			el.find("a").each(function() {
			    $(this).css("position", "relative");
			});
		    }
		}
		
	    })
	);
    }

})(jQuery)