(function ($) {

var offset = 0,
    WIDTH = 150,
    loadedIds = [];

function load_more_videos() {
    var base_video_id = $('.previousvideos div.video:last')[0].id.replace(/^video-/, '');
    
    if ($('.previousvideos .video').length <= offset + 2 && $.inArray(base_video_id, loadedIds) === -1) {
        loadedIds.push(base_video_id);

        $.get("/previous_videos_ajax/" + base_video_id + "/", {}, function(html) {
            $('.previousvideos .slider').append(html);
            disableScrollers();
        });
    }
};

function disableScrollers() {
    if (offset === 0) {
        $('.recent-scrollers .scroll-left').addClass('disabled');
    }
    else {
        $('.recent-scrollers .scroll-left').removeClass('disabled');
    }
    if ($('.previousvideos .video').length <= offset + 2) {
        $('.recent-scrollers .scroll-right').addClass('disabled');
    }
    else {
        $('.recent-scrollers .scroll-right').removeClass('disabled');
    }
};

function scroll(backwards) {
    offset = offset + (backwards ? -2 : 2);
    offset = Math.min(Math.max(offset, 0), $('.previousvideos .video').length - 2);
    $('.previousvideos .slider').animate({'left': (-1 * offset * WIDTH) + 'px'});
    disableScrollers();
    load_more_videos();
};

$(function() {
    $('.recent-scrollers .scroll-right').click(function() {
        scroll();
    });
    $('.recent-scrollers .scroll-left').click(function() {
        scroll(true);
    });
    $('.recent-scrollers').show();
    
    load_more_videos();
    disableScrollers();
});


})(jQuery);