/**
 * Provides image rollover and IE6.0 PNG support.
 * @author Adam J. McIntyre
 */
YAHOO.util.Event.onDOMReady(function(){
    var swaps = YAHOO.util.Selector.query('img.swap');
    for(var i = 0 ; i < swaps.length; i++){
        var el = swaps[i];
        // We need to work in IE 6 PNG support
        // for elements in the form of <a><img>...</a>
        if(YAHOO.env.ua.ie > 0 && YAHOO.env.ua.ie <= 6 && el.src.indexOf('png') > 0) {
            YAHOO.util.Event.addListener(el.parentNode, 'mouseover', function(){
                var cEl = YAHOO.util.Dom.getFirstChild(this);
                var s = cEl.src;
                cEl.src = s.substr(0, s.lastIndexOf('.')) + '_on' + s.substr(s.lastIndexOf('.'));
                this.style.filter = "progid:DXImageTransform.Microsoft.AlphaImageLoader(src='" + cEl.src + "', sizingMethod='image')";
            });
            YAHOO.util.Event.addListener(el.parentNode, 'mouseout', function(){
                var cEl = YAHOO.util.Dom.getFirstChild(this);
                var s = cEl.src;
                cEl.src = s.substr(0,s.indexOf('_on')) + s.substr(s.lastIndexOf('.'));
                this.style.filter = "progid:DXImageTransform.Microsoft.AlphaImageLoader(src='" + cEl.src + "', sizingMethod='image')";
            });
        }
        else {
            YAHOO.util.Event.addListener(el, 'mouseover', function(){
                var s = this.src;
                this.src = s.substr(0, s.lastIndexOf('.')) + '_on' + s.substr(s.lastIndexOf('.'));
            });
            YAHOO.util.Event.addListener(el,'mouseout',function(){
                var s = this.src;
                this.src = s.substr(0,s.indexOf('_on')) + s.substr(s.lastIndexOf('.'));
            });
        }
    }
    
    if(YAHOO.env.ua.ie > 0 && YAHOO.env.ua.ie <= 6){
        var els = YAHOO.util.Selector.query('.replace_png');
        for(var i = 0; i < els.length; i++){
            var bg = YAHOO.util.Dom.getStyle(els[i],'background-image');
            if(bg != 'none'){
                var imgUrl = bg.match(/url\((.*)\)/)[1];
                els[i].style.filter = "progid:DXImageTransform.Microsoft.AlphaImageLoader(src='" + imgUrl +"', sizingMethod='image')";
                els[i].style.backgroundImage = '';   
            }
            else{    // <a><img></a> construct
                var imgObj = YAHOO.util.Dom.getFirstChild(els[i]);
                els[i].style.filter = "progid:DXImageTransform.Microsoft.AlphaImageLoader(src='" + imgObj.src +"', sizingMethod='image')";
                els[i].style.backgroundImage = ''; 
                imgObj.style.visibility = 'hidden';                                  
            }    
        } 
    }
});