Holiday Media JavaScript API from https://lib.hmcms.nl/js/2/ha/booking/hmapi.js unminified with http://unminify.com/.

hmapi.js

window.hmapi || (window.hmapi = function(n) {
    "use strict";
    var i, e = n.document,
        o = function(n, i, o, t) {
            o = e.createElement("script"), o.src = n, o.onload = i, o.onreadystatechange = function(n) {
                n = this.readyState, ("complete" == n || "loaded" == n) && i()
            }, t = e.getElementsByTagName("script")[0], t.parentNode.insertBefore(o, t)
        },
        t = function() {
            var t, r = "https://lib.hmcms.nl/js/2/",
                a = [],
                d = function() {
                    for (t = 2; a.length;) a.shift()()
                },
                u = function() {
                    i.hm && i.hm.libloader ? d() : o(r + "libloader.js?load=ha.booking.widget", d)
                };
            return function(d) {
                if (2 == t ? d() : a.push(d), !t) {
                    var c = n.jQuery ? n.jQuery.fn.jquery.split(".") : [];
                    if (t = 1, c[0] > 1 || c[1] > 7) i = jQuery, u();
                    else {
                        var f = e.createElement("i");
                        f.innerHTML = "<!--[if lt IE 9]>1<![endif]-->", o(r + ("1" === f.innerHTML ? "jquery-1.11.2.js" : "jquery-2.1.3.js"), function() {
                            i = n.jQuery.noConflict(!1), u()
                        })
                    }
                }
            }
        }();
    return {
        load: function() {
            var n = arguments;
            t(function() {
                i.hm.libloader.add.apply(i.hm.libloader, n)
            })
        },
        ready: function(n) {
            t(function() {
                i(e).ready(n)
            })
        }
    }
}(window)), window.hmapi.booking || (window.hmapi.booking = function() {
    return {
        init: function(n) {
            hmapi.ready(function(i) {
                i.hm.libloader.add("ha.booking.widget").done(function() {
                    var e = i(".booking-widget");
                    e.booking(), "function" == typeof n && n.apply(e)
                })
            })
        }
    }
}(window));