Switch Google Account - Bookmark

switch-google-account.js

;(() => {
  /** 
   * User format where the user index is defined as part of the path as '/u/:userIndex/'
   * This format is seen in google calendar.
   * Example: https://calendar.google.com/calendar/u/1/r
   **/
  const formatUserInPath = { 
    getIndex() { return this._regex.exec(location.href)?.[1]; },
    replace(index) { location.href = location.href.replace(this._regex, `/u/${index}/`); },
   _regex:  /\/u\/(.*?)\//
  };

  /**
   * User format where the user index is defined as a query parameter as '?authuser=:userIndex'
   * This format works for most other google products.
   * Example: https://meet.google.com/g1z-ycan-ugs?authuser=1
   */
  /** ?authUser=:userId **/
  const formatUserInQueryParam = { 
    getIndex() {
      const params = this._getParams();
      return params.get('authuser') || "0";
    },
    replace(index) {
      const params = this._getParams();
      params.set('authuser', index);
      location.search = params.toString();
    },
    _getParams() { return new URLSearchParams(location.search); }
  };

  const isGoogleSite = location.href.includes('.google.com');
  if (!isGoogleSite) {
    alert("Not on a google site");
    return;
  }

  /** Order here is important because 'formatUserInQueryParam' will return "0" even if the parameter is not being used. */
  const accountFormats = [
    formatUserInPath,
    formatUserInQueryParam,
  ]
  .filter(format => format.getIndex());

  const accountFormat = accountFormats[0];
  const currentAccount = accountFormat.getIndex();
  const nextAccount = currentAccount === "0" ? "1" : "0";

  accountFormat.replace(nextAccount);
})();