var effect = false;
var effect_regex = /0\.(png|gif|jpg)\)$/

function swapImageUrl(url) {
    effect = effect_regex.test(url);
    return  effect ? 
            url.replace(/0\.(png|gif|jpg)\)$/, '.$1)') : 
            url.replace(/\.(png|gif|jpg)\)$/, '0.$1)');
}
function swapImage(a) {
    url = swapImageUrl(a.style.backgroundImage);
    if(effect) new Effect.Opacity(a, {duration:0.7, from:0.4, to:1.0});
    a.style.backgroundImage = url;
}
function initTeaserTable() {
    if(!(table = $('teaser-table'))) return false;
    image_a = document.getElementsByClassName('image', table)[0].getElementsByTagName('a')
    tds = table.getElementsByTagName('td')
    if(!image_a || !tds || (!tds.length % image_a.length)) return false;
    tr = document.createElement('tr');
    for(i = 0; i < image_a.length; i++) {
        td = document.createElement('td');
        td.style.backgroundImage = swapImageUrl(image_a[i].style.backgroundImage);
        tr.appendChild(td);
        o = new Object;
        o.image_a = image_a[i];
        o.eventHandler = function() {swapImage(this.image_a);}
        for(j = i; j < tds.length; j += image_a.length) {
            tds[j].onmouseover = o.eventHandler.bindAsEventListener(o);
            tds[j].onmouseout = o.eventHandler.bindAsEventListener(o);
        }
    }
    table.appendChild(tr);
    tr.style.display = 'none';
}
function init() {
    initTeaserTable();
}