function trailer_link(clip, size)
{
    //if needed you can branch here instead of sending all iphone and hd to the same place
    //example: switch(clip)...
    if (size == 'iphone') location.href = 'http://itunes.apple.com/WebObjects/MZStore.woa/wa/browserRedirect?url=itms://www.apple.com/moviesxml/s/disney/walle/index.xml%3Fi%3D17';
    else if (size == 'hd') location.href = 'hd/';
    else location.href = clip +'_'+size+'.html';
}

Event.observe(window, 'load', function() {

    //automatic rollovers
    $$('img').each(function (e) {
        var over = e.readAttribute('oversrc');
        if (over != null) {
            var oldsrc = e.src;
            e.observe('mouseover', function(x) {e.src = over});
            e.observe('mouseout', function(x) {e.src = oldsrc});
        }
    });

    //show dropdowns on rollover
    $$('.dropdown-trigger').each(function(e) {
        var id = e.readAttribute('id');
        var drop = new Element('div', {'class': 'dropdown', 'clip': id} ).hide();
        if (e.hasClassName('dropdown-trigger-hd') ) drop.addClassName('dropdown-hd');
        e.insert(drop);
        var offset = Math.round((e.getWidth() - drop.getWidth() ) / 2);
        drop.setStyle({'left': offset+'px'});
        e.observe('mouseover', function(x) {drop.show()});
        e.observe('mouseout', function(x) {drop.hide()});
    });

    //create links in the dropdown menu
    $$('.dropdown').each(function(e) {
        var clip = e.readAttribute('clip');

        var sizes = ['small', 'medium', 'large', 'iphone'];
        if (e.hasClassName('dropdown-hd') ) sizes.push('hd');
        sizes.each(function(size) {
            var link = new Element('div', {'class': 'link '+size, 'clip': clip, 'size': size});
            e.insert(link);
        });
    });

    //handle link clicks
    $$('.dropdown .link').each(function(e) {
        var clip = e.readAttribute('clip');
        var size = e.readAttribute('size');
        e.observe('click', function(x) {trailer_link(clip, size);} );
    });

});