var num_frames    = 0;
var current_image = 1;
var frame_width   = 323;

function rotateAd(direction, e) {
    e.preventDefault();
    if (direction == 'previous') {
        if (current_image == 1) return;
        var x_axis = frame_width;
        current_image--;
        if (current_image == 1) {
            $('carouselleft').writeAttribute('src', '/images/button-left-off.gif');
        }
        $('carouselright').writeAttribute('src', '/images/button-right.gif');
    }
    else if (direction == 'next') {
        if (current_image == num_frames - 1) return;
        var x_axis = -frame_width;
        current_image++;
        if (current_image == num_frames - 1) {
            $('carouselright').writeAttribute('src', '/images/button-right-off.gif');
        }
        $('carouselleft').writeAttribute('src', '/images/button-left.gif');
    }
    new Effect.Move($('carousel'), {
        x: x_axis,
        y: 0,
        duration: 1,
        queue: 'end'
    });
}

document.observe('dom:loaded', function() {
    $('carouselleft').writeAttribute('src', '/images/button-left-off.gif');
    num_frames = $$('#carousel li').length;
    if (Prototype.Browser.IE && parseInt(navigator.userAgent.substring(navigator.userAgent.indexOf("MSIE") + 5)) == 6) {
        $('lefttrigger').remove();
        $('righttrigger').remove();
        $('carousel').style.width = '656px';
        if (num_frames > 2) {
            var counter = 0;
            $$('#carousel li').each(function(li) {
                counter++;
                if (counter > 2) {
                    li.remove();
                }
            });
        }
    }
    else {
        var triggers = new Hash({lefttrigger: 'previous', righttrigger: 'next'})
        triggers.each(function(f) {
            $(f.key).observe('click', function(e) {
                rotateAd(f.value, e);
            });
        });
    }
});