/*
 * jQuery ifixpng plugin
 * (previously known as pngfix)
 * Version 2.1  (23/04/2008)
 * @requires jQuery v1.1.3 or above
 *
 * Examples at: http://jquery.khurshid.com
 * Copyright (c) 2007 Kush M.
 * Dual licensed under the MIT and GPL licenses:
 * http://www.opensource.org/licenses/mit-license.php
 * http://www.gnu.org/licenses/gpl.html
 */
 
/**
  *
  * @example
  *
  * optional if location of pixel.gif if different to default which is images/pixel.gif
  * $.ifixpng('media/pixel.gif');
  *
  * $('img[@src$=.png], #panel').ifixpng();
  *
  * @apply hack to all png images and #panel which icluded png img in its css
  *
  * @name ifixpng
  * @type jQuery
  * @cat Plugins/Image
  * @return jQuery
  * @author jQuery Community
  */
 
(function($) {

   /**
	 * helper variables and function
	 */
   $.ifixpng = function(sizingMethod) {
      $.ifixpng.method = sizingMethod;
   };
	
   $.ifixpng.getPixel = function() {
      return '/imgs/pixel.gif';
   };
	
   var hack = {
      ltie7  : $.browser.msie && $.browser.version < 7,
      filter : function(src) {
	 if($.ifixpng.method==undefined){
	    return "progid:DXImageTransform.Microsoft.AlphaImageLoader(enabled=true,sizingMethod=crop,src='"+src+"')";
	 }else{
	    return "progid:DXImageTransform.Microsoft.AlphaImageLoader(enabled=true,sizingMethod="+$.ifixpng.method+",src='"+src+"')";
	 }
      }
   };
	
   /**
	 * Applies ie png hack to selected dom elements
	 *
	 * $('img[@src$=.png]').ifixpng();
	 * @desc apply hack to all images with png extensions
	 *
	 * $('#panel, img[@src$=.png]').ifixpng();
	 * @desc apply hack to element #panel and all images with png extensions
	 *
	 * @name ifixpng
	 */
	 
   $.fn.ifixpng = hack.ltie7 ? function() {
      return this.each(function() {
	 var $$ = $(this);
	 // in case rewriting urls
	 var base = $('base').attr('href');
	 if (base) {
	    // remove anything after the last '/'
	    base = base.replace(/\/[^\/]+$/,'/');
	 }
	 if ($$.is('img') || $$.is('input')) { // hack image tags present in dom
	    if ($$.attr('src')) {
	       if ($$.attr('src').match(/.*\.png([?].*)?$/i)) { // make sure it is png image
		  // use source tag value if set
		  var source = (base && $$.attr('src').search(/^(\/|http:)/i)) ? base + $$.attr('src') : $$.attr('src');
		  // apply filter
		  $$.css({
		     filter:hack.filter(source),
		     width:$$.width(),
		     height:$$.height()
		  })
		  .attr({
		     src:$.ifixpng.getPixel()
		  })
		  .positionFix();
	       }
	    }
	 } else { // hack png css properties present inside css
	    var image = $$.css('backgroundImage');
	    if (image.match(/^url\(["']?(.*\.png([?].*)?)["']?\)$/i)) {
	       image = RegExp.$1;
	       image = (base && image.substring(0,1)!='/') ? base + image : image;
	       $$.css({
		  backgroundImage:'none',
		  filter:hack.filter(image)
	       })
	       .children().children().positionFix();
	    }
	 }
      });
   } : function() {
      return this;
   };
	
   /**
	 * Removes any png hack that may have been applied previously
	 *
	 * $('img[@src$=.png]').iunfixpng();
	 * @desc revert hack on all images with png extensions
	 *
	 * $('#panel, img[@src$=.png]').iunfixpng();
	 * @desc revert hack on element #panel and all images with png extensions
	 *
	 * @name iunfixpng
	 */
	 
   $.fn.iunfixpng = hack.ltie7 ? function() {
      return this.each(function() {
	 var $$ = $(this);
	 var src = $$.css('filter');
	 if (src.match(/src=["']?(.*\.png([?].*)?)["']?/i)) { // get img source from filter
	    src = RegExp.$1;
	    if ($$.is('img') || $$.is('input')) {
	       $$.attr({
		  src:src
	       }).css({
		  filter:''
	       });
	    } else {
	       $$.css({
		  filter:'',
		  background:'url('+src+')'
	       });
	    }
	 }
      });
   } : function() {
      return this;
   };
	
   /**
	 * positions selected item relatively
	 */
	 
   $.fn.positionFix = function() {
      return this.each(function() {
	 var $$ = $(this);
	 var position = $$.css('position');
	 if (position != 'absolute' && position != 'relative') {
	    $$.css({
	       position:'relative'
	    });
	 }
      });
   };

})(jQuery);