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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
"use strict";
/**
*
* Sites often rely on the Google Analytics window object and will
* break if it fails to load or is blocked. This shim works around
* such breakage.
*
* Sites also often use the Google Optimizer (asynchide) code snippet,
* only for it to cause multi-second delays if Google Analytics does
* not load. This shim also avoids such delays.
*
* They also rely on Google Tag Manager, which often goes hand-in-
* hand with Analytics, but is not always blocked by anti-tracking
* lists. Handling both in the same shim handles both cases.
*/
if (window[window.GoogleAnalyticsObject || "ga"]?.loaded === undefined) {
const DEFAULT_TRACKER_NAME = "t0";
const trackers = new Map();
const run = function (fn, ...args) {
if (typeof fn === "function") {
try {
fn(...args);
} catch (e) {
console.error(e);
}
}
};
const create = (id, cookie, name, opts) => {
id = id || opts?.trackerId;
if (!id) {
return undefined;
}
cookie = cookie || opts?.cookieDomain || "_ga";
name = name || opts?.name || DEFAULT_TRACKER_NAME;
if (!trackers.has(name)) {
let props;
try {
props = new Map(Object.entries(opts));
} catch (_) {
props = new Map();
}
trackers.set(name, {
get(p) {
if (p === "name") {
return name;
} else if (p === "trackingId") {
return id;
} else if (p === "cookieDomain") {
return cookie;
}
return props.get(p);
},
ma() {},
requireSync() {},
send() {},
set(p, v) {
if (typeof p !== "object") {
p = Object.fromEntries([[p, v]]);
}
for (const k in p) {
props.set(k, p[k]);
if (k === "hitCallback") {
run(p[k]);
}
}
},
});
}
return trackers.get(name);
};
const cmdRE = /((?<name>.*?)\.)?((?<plugin>.*?):)?(?<method>.*)/;
function ga(cmd, ...args) {
if (arguments.length === 1 && typeof cmd === "function") {
run(cmd, trackers.get(DEFAULT_TRACKER_NAME));
return undefined;
}
if (typeof cmd !== "string") {
return undefined;
}
const groups = cmdRE.exec(cmd)?.groups;
if (!groups) {
console.error("Could not parse GA command", cmd);
return undefined;
}
let { name, plugin, method } = groups;
if (plugin) {
return undefined;
}
if (cmd === "set") {
trackers.get(name)?.set(args[0], args[1]);
}
if (method === "remove") {
trackers.delete(name);
return undefined;
}
if (cmd === "send") {
run(args.at(-1)?.hitCallback);
return undefined;
}
if (method === "create") {
let id, cookie, fields;
for (const param of args.slice(0, 4)) {
if (typeof param === "object") {
fields = param;
break;
}
if (id === undefined) {
id = param;
} else if (cookie === undefined) {
cookie = param;
} else {
name = param;
}
}
return create(id, cookie, name, fields);
}
return undefined;
}
Object.assign(ga, {
create: (a, b, c, d) => ga("create", a, b, c, d),
getAll: () => Array.from(trackers.values()),
getByName: name => trackers.get(name),
loaded: true,
remove: t => ga("remove", t),
});
const q = window[window.GoogleAnalyticsObject || "ga"]?.q;
window[window.GoogleAnalyticsObject || "ga"] = ga;
if (Array.isArray(q)) {
const push = o => {
ga(...o);
return true;
};
q.push = push;
q.forEach(o => push(o));
}
const dl = window.dataLayer;
if (Array.isArray(dl) && !dl.find(e => e["gtm.start"])) {
const push = function (o) {
setTimeout(() => run(o?.eventCallback), 1);
return true;
};
dl.push = push;
dl.forEach(o => push(o));
}
run(window.dataLayer?.hide?.end);
}
if (!window?.gaplugins?.Linker) {
window.gaplugins = window.gaplugins || {};
window.gaplugins.Linker = class {
autoLink() {}
decorate(url) {
return url;
}
passthrough() {}
};
}