Twitch Auto Stream Live Checker

twitchlivebot.js

// ==UserScript==
// @name         Twitch Live Checker Autobot
// @namespace    https://gist.github.com/mpratt14/
// @version      2.1
// @description  Automatically open a Twitch stream when they go live when watching someone else or offline
// @author       DatPratt
// @match        https://*.twitch.tv/*
// @icon         https://www.google.com/s2/favicons?domain=twitch.tv
// @grant        none
// ==/UserScript==

(function() {
    'use strict';

    const urls = [
        "streamer1",
        "streamer2",
        "streamer3"
    ]

    const root = "https://www.twitch.tv/";
    var live, notlive, request, requests, url, previous

    function clearChecker () {
        live = []; notlive = []; requests = [];
        previous ??= document.referrer;
    }

    function pickURL () {
        console.log("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~",
                   "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");

        for (let i = 0; i < requests.length; i++) {
            url = urls[i];
            request = requests[i];
            if (!isLive()) {
                if (live.length == 0 && window.location.href.includes(url)) {
                    console.log("TWITCH LIVE CHECKER:", "failed to check", url, "...aborting...");
                    break;
                }
                continue;
            }
        }

        console.log("TWITCH LIVE CHECKER:", live, "are live");
        console.log("TWITCH LIVE CHECKER:", notlive, "are NOT live");
        console.log("TWITCH LIVE CHECKER:", "out of", urls);
        //console.log("TWITCH LIVE CHECKER:", requests);

        gotoURL();

        clearChecker();

        for (let i = 0; i < urls.length; i++) {
            request = new XMLHttpRequest();
            requests.push(request);
            if (!getHTML(i)) {
                break;
            }
        }

        console.log("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~",
                   "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
    }

    function gotoURL () {
        if (typeof live[0] !== "undefined") {
            if (!window.location.href.includes(live[0]) &&
               !window.location.href.includes("videos") &&
               !window.location.href.includes("popout")) {
                if (window.location.href.includes("referrer")) {
                    window.history.replaceState({}, document.title, window.location.href.split("?")[0].split("/")[3]);
                } else if (previous.includes(live[0]) ||
                           previous.includes("referrer")) {
                    previous = window.location.href;
                } else {
                    window.location.href = root + live[0];
                }
            } else {
                console.log("TWITCH LIVE CHECKER:", "we are watching", window.location.href, "already");
            }
        }
    }

    function isLive () {
        if (request.responseText.includes(url)) {
            if (request.responseText.includes("isLiveBroadcast")) {
                live.push(url);
            } else {
                notlive.push(url);
            }
            return true;
        } else {
            console.log("TWITCH LIVE CHECKER:", "failed to check", url, "...skipping...");
            return false;
        }
    }

    function getHTML (i) {
        requests[i].open("GET", root + urls[i]);
        //console.log("TWITCH LIVE CHECKER:", "fetching", root + urls[i]);
        requests[i].onreadystatechange = function () {
            if(this.readyState === XMLHttpRequest.DONE) {
                var status = this.status;
                if (status === 0 || (status >= 200 && status < 400)) {
                    //console.log("DONE", this.readyState, this.responseURL);
                } else {
                    console.log("ERR:", this.readyState, this.responseURL);
                }
            }
        }
        try {
            request.send();
            return true;
        } catch(err) {
            console.log("TWITCH LIVE CHECKER:", "failed to fetch", urls[i], "...skipping...");
            return false;
        }
    }

    clearChecker();
    var timer = setInterval(pickURL, 111111);
    console.log("TWITCH LIVE CHECKER: USERSCRIPT STARTED");
})();