// This mess of code checks the scroll position every second (or so)
// and plays or pauses the autoplaying slideshows accordingly.
// This way, the browser isn't animating stuff you can't even see.

var watcher = {

    init: function(slideshows){
        watcher.slideshows = slideshows;
        watcher.setPositions().attach().check();
        return watcher;
    },

    check: function (){
        var scroll = window.getScroll().y;
        watcher.slideshows.each(function(item){
            if (item.position.stop <= scroll || item.position.start > scroll){
                if (item.isLooping) item.pause();
                return;
            }

            if (item.position.start <= scroll){
                if (!item.isLooping) item.show('next').play();
            }
        });
        setTimeout(watcher.check, 500);
        return watcher;
    },

    setPositions: function (){
        watcher.slideshows.each(function(item){
            var el = $(item),
                top = el.getPosition().y;

            item.position = {
                start: top - window.getSize().y,
                stop: top + el.getSize().y
            };
        });
        return watcher;
    },

    attach: function (){
        window.addEvent('resize', watcher.setPositions);
        return watcher;
    }
}


document.addEvent('domready', function(){
    $$('html')[0].removeClass('not-ready').removeClass('no-js');
    watcher.init([
        flickr, basic.pause(), 
        css.pause(), 
        declarative.pause()
    ]);
});