var IEPNGFix = window.IEPNGFix || {};

IEPNGFix.data = IEPNGFix.data || {};

IEPNGFix.blankImg = 'images/x.gif';



IEPNGFix.fix = function(elm, src, t) {

	// Applies an image 'src' to an element 'elm' using the DirectX filter.

	// If 'src' is null, filter is disabled.

	// Disables the 'hook' to prevent infinite recursion on setting BG/src.

	// 't' = type, where background tile = 0, background = 1, IMG SRC = 2.



	var h = IEPNGFix.hook.enabled;

	IEPNGFix.hook.enabled = 0;

	var f = 'DXImageTransform.Microsoft.AlphaImageLoader';

	src = (src || '').replace(/\(/g, '%28').replace(/\)/g, '%29');

	if (src && !(/IMG|INPUT/.test(elm.nodeName) && (t != 2)) && elm.currentStyle.width == 'auto' && elm.currentStyle.height == 'auto') {

		elm.style.width = elm.offsetWidth + 'px';

		elm.style.height = elm.clientHeight + 'px';

		if (elm.currentStyle.display == 'inline') {

			elm.style.display = 'inline-block';

		}

	}

	if (t == 1) {

		elm.style.backgroundImage = 'url("' + IEPNGFix.blankImg + '")';

	}

	if (t == 2) {

		elm.src = IEPNGFix.blankImg;

	}

	if (elm.filters[f]) {

		elm.filters[f].enabled = src ? true : false;

		if (src) {

			elm.filters[f].src = src;

		}

	} else if (src) {

		elm.style.filter = 'progid:' + f + '(src="' + src +	'",sizingMethod="' + (t == 2 ? 'scale' : 'crop') + '")';

	}

	IEPNGFix.hook.enabled = h;

};





IEPNGFix.process = function(elm, init) {

	// Checks the onpropertychange event (on first 'init' run, a fake event)

	// and calls the filter-applying-functions.



	if (!/MSIE (5\.5|6)/.test(navigator.userAgent) || typeof elm.filters == 'unknown') {

		return;

	}

	if (!IEPNGFix.data[elm.uniqueID]) {

		IEPNGFix.data[elm.uniqueID] = {

			className: ''

		};

	}

	var data = IEPNGFix.data[elm.uniqueID],

		evt = init ? { propertyName: 'src,backgroundImage' } : event,

		isSrc = /src/.test(evt.propertyName),

		isBg = /backgroundImage/.test(evt.propertyName),

		isPos = /width|height|background(Pos|Rep)/.test(evt.propertyName),

		isClass = !init && ((elm.className != data.className) &&

			(elm.className || data.className));

	if (!(isSrc || isBg || isPos || isClass)) {

		return;

	}

	data.className = elm.className;

	var blank = IEPNGFix.blankImg.match(/([^\/]+)$/)[1],

		eS = elm.style,

		eCS = elm.currentStyle;



	// Required for Whatever:hover - erase set BG if className changes.

	if (

		isClass && (eS.backgroundImage.indexOf('url(') == -1 ||

		eS.backgroundImage.indexOf(blank) > -1)

	) {

		return setTimeout(function() {

			eS.backgroundImage = '';

		}, 0);

	}



	// Foregrounds.

	if (isSrc && elm.src &&  { IMG: 1, INPUT: 1 }[elm.nodeName]) {

		if ((/\.png/i).test(elm.src)) {

			IEPNGFix.fix(elm, elm.src, 2);

		} else if (elm.src.indexOf(blank) == -1) {

			IEPNGFix.fix(elm, '');

		}

	}



	// Backgrounds.

	var bgSrc = eCS.backgroundImage || eS.backgroundImage;

	if ((bgSrc + elm.src).indexOf(blank) == -1) {

		var bgPNG = bgSrc.match(/url[("']+(.*\.png[^\)"']*)[\)"']/i);

		if (bgPNG) {

			if (IEPNGFix.tileBG && !{ IMG: 1, INPUT: 1 }[elm.nodeName]) {

				IEPNGFix.tileBG(elm, bgPNG[1]);

				IEPNGFix.fix(elm, '', 1);

			} else {

				if (data.tiles && data.tiles.src) {

					IEPNGFix.tileBG(elm, '');

				}

				IEPNGFix.fix(elm, bgPNG[1], 1);

				IEPNGFix.childFix(elm);

			}

		} else {

			if (data.tiles && data.tiles.src) {

				IEPNGFix.tileBG(elm, '');

			}

			IEPNGFix.fix(elm, '');

		}

	} else if ((isPos || isClass) && data.tiles && data.tiles.src) {

		IEPNGFix.tileBG(elm, data.tiles.src);

	}



	if (init) {

		IEPNGFix.hook.enabled = 1;

		elm.attachEvent('onpropertychange', function(){

			IEPNGFix.hook(elm);

		});

	}

};



IEPNGFix.childFix = function(elm) {

	// "hasLayout" fix for unclickable children inside PNG backgrounds.

	var tags = [

			'a',

			'input',

			'select',

			'textarea',

			'button',

			'iframe',

			'object'

		],

		t = tags.length,

		tFix = [];

	while (t--) {

		var pFix = elm.all.tags(tags[t]),

			e = pFix.length;

		while (e--) {

			tFix.push(pFix[e]);

		}

	}

	t = tFix.length;

	if (t && (/relative|absolute/i).test(elm.currentStyle.position)) {

		alert('IEPNGFix: Unclickable children of element:' +

			'\n\n<' + elm.nodeName + (elm.id && ' id=' + elm.id) + '>');

	}

	while (t--) {

		if (!(/relative|absolute/i).test(tFix[t].currentStyle.position)) {

			tFix[t].style.position = 'relative';

		}

	}

};



IEPNGFix.hook = function(elm) {

	if (IEPNGFix.hook.enabled) {

		IEPNGFix.process(elm, 0);

	}

};



IEPNGFix.tileBG = function(elm, pngSrc, ready) {

	// Params: A reference to a DOM element, the PNG src file pathname, and a

	// hidden "ready-to-run" passed when called back after image preloading.



	var data = IEPNGFix.data[elm.uniqueID],

		elmW = Math.max(elm.clientWidth, elm.scrollWidth),

		elmH = Math.max(elm.clientHeight, elm.scrollHeight),

		bgX = elm.currentStyle.backgroundPositionX,

		bgY = elm.currentStyle.backgroundPositionY,

		bgR = elm.currentStyle.backgroundRepeat;



	// Cache of DIVs created per element, and image preloader/data.

	if (!data.tiles) {

		data.tiles = {

			elm: elm,

			src: '',

			cache: [],

			img: new Image(),

			old: {}

		};

	}

	var tiles = data.tiles,

		pngW = tiles.img.width,

		pngH = tiles.img.height;



	if (pngSrc) {

		if (!ready && pngSrc != tiles.src) {

			// New image? Preload it with a callback to detect dimensions.

			tiles.img.onload = function() {

				tiles.img.onload = null;

				IEPNGFix.tileBG(elm, pngSrc, 1);

			};

			return tiles.img.src = pngSrc;

		}

	} else {

		// No image?

		if (tiles.src) ready = 1;

		pngW = pngH = 0;

	}

	tiles.src = pngSrc;



	if (!ready && elmW == tiles.old.w && elmH == tiles.old.h &&

		bgX == tiles.old.x && bgY == tiles.old.y && bgR == tiles.old.r) {

		return;

	}



	// Convert English and percentage positions to pixels.

	var pos = {

			top: '0%',

			left: '0%',

			center: '50%',

			bottom: '100%',

			right: '100%'

		},

		x,

		y,

		pc;

	x = pos[bgX] || bgX;

	y = pos[bgY] || bgY;

	if (pc = x.match(/(\d+)%/)) {

		x = Math.round((elmW - pngW) * (parseInt(pc[1]) / 100));

	}

	if (pc = y.match(/(\d+)%/)) {

		y = Math.round((elmH - pngH) * (parseInt(pc[1]) / 100));

	}

	x = parseInt(x);

	y = parseInt(y);



	// Handle backgroundRepeat.

	var repeatX = { 'repeat': 1, 'repeat-x': 1 }[bgR],

		repeatY = { 'repeat': 1, 'repeat-y': 1 }[bgR];

	if (repeatX) {

		x %= pngW;

		if (x > 0) x -= pngW;

	}

	if (repeatY) {

		y %= pngH;

		if (y > 0) y -= pngH;

	}



	// Go!

	IEPNGFix.hook.enabled = 0;

	if (!({ relative: 1, absolute: 1 }[elm.currentStyle.position])) {

		elm.style.position = 'relative';

	}

	var count = 0,

		xPos,

		maxX = repeatX ? elmW : x + 0.1,

		yPos,

		maxY = repeatY ? elmH : y + 0.1,

		d,

		s,

		isNew;

	if (pngW && pngH) {

		for (xPos = x; xPos < maxX; xPos += pngW) {

			for (yPos = y; yPos < maxY; yPos += pngH) {

				isNew = 0;

				if (!tiles.cache[count]) {

					tiles.cache[count] = document.createElement('div');

					isNew = 1;

				}

				var clipR = (xPos + pngW > elmW ? elmW - xPos : pngW),

					clipB = (yPos + pngH > elmH ? elmH - yPos : pngH);

				d = tiles.cache[count];

				s = d.style;

				s.behavior = 'none';

				s.left = xPos + 'px';

				s.top = yPos + 'px';

				s.width = clipR + 'px';

				s.height = clipB + 'px';

				s.clip = 'rect(' +

					(yPos < 0 ? 0 - yPos : 0) + 'px,' +

					clipR + 'px,' +

					clipB + 'px,' +

					(xPos < 0 ? 0 - xPos : 0) + 'px)';

				s.display = 'block';

				if (isNew) {

					s.position = 'absolute';

					s.zIndex = -999;

					if (elm.firstChild) {

						elm.insertBefore(d, elm.firstChild);

					} else {

						elm.appendChild(d);

					}

				}

				IEPNGFix.fix(d, pngSrc, 0);

				count++;

			}

		}

	}

	while (count < tiles.cache.length) {

		IEPNGFix.fix(tiles.cache[count], '', 0);

		tiles.cache[count++].style.display = 'none';

	}



	IEPNGFix.hook.enabled = 1;



	// Cache so updates are infrequent.

	tiles.old = {

		w: elmW,

		h: elmH,

		x: bgX,

		y: bgY,

		r: bgR

	};

};



IEPNGFix.update = function() {

	// Update all PNG backgrounds.

	for (var i in IEPNGFix.data) {

		var t = IEPNGFix.data[i].tiles;

		if (t && t.elm && t.src) {

			IEPNGFix.tileBG(t.elm, t.src);

		}

	}

};

IEPNGFix.update.timer = 0;



if (window.attachEvent && !window.opera) {	

	window.attachEvent('onresize', function() {

		clearTimeout(IEPNGFix.update.timer);

		IEPNGFix.update.timer = setTimeout(IEPNGFix.update, 100);

	});

}







/*

init IE PNG fix

*/

window.addEvent(Browser.Engine.trident4 ? 'load' : 'domready', function(){

	// init fix png

	if(Browser.Engine.trident4){

		$$('.png').each(function(fixme){			

			IEPNGFix.process(fixme, 1);				

		});	

	}

	// init moo hover

	new MooHover();

});