/*
Script: FixPNG.js
	Extends the Browser hash object to include methods useful in managing the window location and urls.

License:
	http://www.clientcide.com/wiki/cnet-libraries#license
*/
$extend(Browser, {
	fixPNG: function(el) {
		try {
			if (Browser.Engine.trident4){
				el = $(el);
				if (!el) return el;
				if (el.get('tag') == "img" && el.get('src').test(".png")) {
					var vis = el.isVisible();
					try { //safari sometimes crashes here, so catch it
						dim = el.getSize();
					}catch(e){}
					if(!vis){
						var before = {};
						//use this method instead of getStyles 
						['visibility', 'display', 'position'].each(function(style){
							before[style] = this.style[style]||'';
						}, this);
						//this.getStyles('visibility', 'display', 'position');
						this.setStyles({
							visibility: 'hidden',
							display: 'block',
							position:'absolute'
						});
						dim = el.getSize(); //works now, because the display isn't none
						this.setStyles(before); //put it back where it was
						el.hide();
					}
					var replacement = new Element('span', {
						id:(el.id)?el.id:'',
						'class':(el.className)?el.className:'',
						title:(el.title)?el.title:(el.alt)?el.alt:'',
						styles: {
							display: vis?'inline-block':'none',
							width: dim.x,
							height: dim.y,
							filter: "progid:DXImageTransform.Microsoft.AlphaImageLoader (src='" 
								+ el.src + "', sizingMethod='scale');"
						},
						src: el.src
					});
					if(el.style.cssText) {
						try {
							var styles = {};
							var s = el.style.cssText.split(';');
							s.each(function(style){
								var n = style.split(':');
								styles[n[0]] = n[1];
							});
							replacement.setStyle(styles);
						} catch(e){ dbug.log('fixPNG1: ', e)}
					}
					if(replacement.cloneEvents) replacement.cloneEvents(el);
					replacement.replaces(el);
				} else if (el.get('tag') != "img") {
				 	var imgURL = el.getStyle('background-image');
				 	if (imgURL.test(/\((.+)\)/)){
				 		el.setStyles({
				 			background: '',
				 			filter: "progid:DXImageTransform.Microsoft.AlphaImageLoader(enabled='true', sizingMethod='crop', src=" + imgURL.match(/\((.+)\)/)[1] + ")"
				 		});
				 	};
				}
			}
		} catch(e) {dbug.log('fixPNG2: ', e)}
	},
  pngTest: /\.png$/, // saves recreating the regex repeatedly
  scanForPngs: function(el, className) {
    className = className||'fixPNG';
    //TODO: should this also be testing the css background-image property for pngs?
    //Q: should it return an array of all those it has tweaked?
    if (document.getElements){ // more efficient but requires 'selectors'
      el = $(el||document.body);
      el.getElements('img[src$=.png]').addClass(className);
    } else { // scan the whole page
      var els = $$('img').each(function(img) {
        if (Browser.pngTest(img.src)){
          img.addClass(className);
        }
      });
    }
  }
});
if(Browser.Engine.trident4) window.addEvent('domready', function(){$$('img.fixPNG').each(Browser.fixPNG)});