Reload-At-Wallclock.user.js

Reload-At-Wallclock.user.js

// ==UserScript==
// @name         Reload at Wallclock
// @namespace    http://tampermonkey.net/
// @version      0.1
// @description  Reload at Wallclock
// @author       You
// @match        http://worldtimeapi.org/api/timezone/Europe/Berlin.txt
// @match        https://tickets.events.ccc.de/*
// @grant        none
// ==/UserScript==

(function() {
    'use strict';
    // Edit here: /////////////////////////////////////
    var target_datetime='1970-12-02T15:00:00.000+0100';
    ///////////////////////////////////////////////////

    var target = new Date(target_datetime);
    console.log("Userscript: " + target_datetime + " parsed as " + target.toLocaleString() + ", " + target.getMilliseconds() + "ms");
    var now = new Date();
    if (target < now){
        console.log("Userscript: Too late to reload at " + target.toLocaleString() + ", " + target.getMilliseconds() + "ms");
    } else {
        console.log("Userscript: Valid reload time: " + target.toLocaleString() + ", " + target.getMilliseconds() + "ms");
        var diff_ms = target - now;
        setTimeout(function() { location.reload() }, diff_ms);
        console.log("Userscript: Timeout set. Will reload in: " + diff_ms + " ms");
        window.setInterval(function() { console.log("Userscript: " + Math.floor((target - new Date()) / 1000) + " s remaining.") }, 10000);
    }
})();