sticky.js

'use strict';
! function (e) {
    "function" == typeof define && define.amd ? define(e) : "undefined" != typeof module && module.exports ? module.exports = e() : window.enterView = e.call(this)
}(function () {
    var e = function (e) {
        function n() {
            g = window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame || window.msRequestAnimationFrame || function (e) {
                return setTimeout(e, 1e3 / 60)
            }
        }

        function t() {
            if (h && "number" == typeof h) {
                var e = Math.min(Math.max(0, h), 1);
                return q - e * q
            }
            return q
        }

        function i() {
            var e = document.documentElement.clientHeight,
                n = window.innerHeight || 0;
            q = Math.max(e, n)
        }

        function o() {
            y = !1;
            var e = t();
            A = A.filter(function (n) {
                var t = n.getBoundingClientRect(),
                    i = t.top,
                    o = i < e;
                if (o && !n.__enter_view) {
                    if (m(n), _) return !1
                } else !o && n.__enter_view && w && w(n);
                return n.__enter_view = o, !0
            }), A.length || window.removeEventListener("scroll", r, !0)
        }

        function r() {
            y || (y = !0, g(o))
        }

        function u() {
            i(), o()
        }

        function f(e) {
            for (var n = e.length, t = [], i = 0; i < n; i += 1) t.push(e[i]);
            return t
        }

        function c(e) {
            var n = arguments.length > 1 && void 0 !== arguments[1] ? arguments[1] : document;
            return "string" == typeof e ? f(n.querySelectorAll(e)) : e instanceof NodeList ? f(e) : e instanceof Array ? e : void 0
        }

        function d() {
            A = c(l)
        }

        function a() {
            window.addEventListener("resize", u, !0), window.addEventListener("scroll", r, !0), u()
        }

        function s() {
            var e = l && m;
            e || console.error("must set selector and enter options"), n(), d(), a(), o()
        }
        var l = e.selector,
            m = e.enter,
            w = e.exit,
            v = e.offset,
            h = void 0 === v ? 0 : v,
            p = e.once,
            _ = void 0 !== p && p,
            g = null,
            y = !1,
            A = [],
            q = 0;
        s()
    };
    return e
});