(function ($) {
    "use strict";
    var $body = $('body'),
        $window = $(window),
        $siteWrapper = $('#site-wrapper'),
        $document = $(document);
    var APP = {};

    APP.animation = {
        delay: 40,
        itemQueue: [],
        queueTimer: null,
        $wrapper: null,
        init: function () {
            var _self = this;
            _self.$wrapper = $body;
            _self.itemQueue = [];
            _self.queueTimer = null;
            if (typeof delay !== 'undefined') {
                _self.delay = delay;
            }
            _self.itemQueue["animated_0"] = [];
            $body.find('#content').find('>div,>section').each(function (index) {
                $(this).attr('data-animated-id', (index + 1));
                _self.itemQueue["animated_" + (index + 1)] = [];
            });
            setTimeout(function () {
                _self.registerAnimation();
            }, 0);
        },
        registerAnimation: function () {
            var _self = this;
            $('[data-animate]:not(.animated)', _self.$wrapper).waypoint(function () {
                var _el = this.element ? this.element : this,
                    $this = $(_el);
                if ($this.is(":visible")) {
                    var $animated_wrap = $this.closest("[data-animated-id]"),
                        animated_id = '0';
                    if ($animated_wrap.length) {
                        animated_id = $animated_wrap.data('animated-id');
                    }
                    _self.itemQueue['animated_' + animated_id].push(_el);
                    _self.processItemQueue();
                } else {
                    $this.addClass($this.data('animate')).addClass('animated');
                }
            }, {
                offset: '90%',
                triggerOnce: true
            });
        },
        processItemQueue: function () {
            var _self = this;
            if (_self.queueTimer) return;
            _self.queueTimer = window.setInterval(function () {
                var has_queue = false;
                for (var animated_id in _self.itemQueue) {
                    if (_self.itemQueue[animated_id].length) {
                        has_queue = true;
                        break;
                    }
                }
                if (has_queue) {
                    for (var animated_id in _self.itemQueue) {
                        var $item = $(_self.itemQueue[animated_id].shift());
                        $item.addClass($item.data('animate')).addClass('animated');
                    }
                    _self.processItemQueue();
                } else {
                    window.clearInterval(_self.queueTimer);
                    _self.queueTimer = null
                }
            }, _self.delay);
        }
    };

    $(document).ready(function () {
        APP.animation.init();
    });
})(jQuery);