Autoupdate EzShare web GUI on new photo

ezshare_autoupdate.user.js

// ==UserScript==
// @name         EzShare Autoupdate
// @namespace    http://tampermonkey.net/
// @version      0.181023
// @description  Autoupdate EzShare web GUI on new photo
// @author       artniko@gmail.com
// @match        http://ezshare.card/*
// @grant       GM_xmlhttpRequest
// @grant       GM.xmlHttpRequest
// @grant       GM.getValue
// @grant       GM.setValue
// ==/UserScript==

(function() {
    'use strict';

    if (document.getElementById("srcPic") === null) {
        return;
    }

    function getCookie(name) {
        var matches = document.cookie.match(new RegExp(
            "(?:^|; )" + name.replace(/([\.$?*|{}\(\)\[\]\\\/\+^])/g, '\\$1') + "=([^;]*)"
        ));
        return matches ? decodeURIComponent(matches[1]) : false;
    }

    function setCookie(name, value, options) {
        options = options || {};

        options.expires = "Tue, 19 Jan 2038 03:14:07 GMT";
        options.path = "/";

        value = encodeURIComponent(value);

        var updatedCookie = name + "=" + value;

        for (var propName in options) {
            updatedCookie += "; " + propName;
            var propValue = options[propName];
            if (propValue !== true) {
                updatedCookie += "=" + propValue;
            }
        }

        document.cookie = updatedCookie;
    }

    var counter = 0;
    var wait_limit = 500;
    var errors_limit = 100;
    var check_interval = 500; //ms
    var updates_started = true;
    //stop_updates = localStorage.getItem("stop_updates");
    updates_started = getCookie("updates_started");

    var toggle_link = '<a href="#" id="toggle">Stop</a>'

    //document.body.innerHTML += '<br><br><br><br><div class="log" id="log" style = "position: absolute; bottom: 0; width: 80%">Autoupdate waiting...</div>';
    var tr = document.getElementById("picInfo").insertRow(1);
    var td = tr.insertCell(0);
    td.innerHTML += '<div class="log" id="log" align = "center" style = "position: absolute; bottom: 0; font-size: 14px; width: 50%">Autoupdate waiting...</div>';

    function toggle_updates() {
        updates_started = !updates_started;
        if (updates_started) {
            start_updates();
        }
        else {
            stop_updates1();
        }
    }

    function start_updates() {
        counter = 0;
        setCookie("updates_started", updates_started);
        toggle_link = '<a href="#" id="toggle">Stop ' + getCookie("updates_started")+ '</a>';
        check_updates();
    }

    function stop_updates1() {
        setCookie("updates_started", updates_started);
        toggle_link = '<a href="#" id="toggle">Start ' + getCookie("updates_started")+ ' </a>';
    }

    if (updates_started) {
        start_updates();
    }
    else {
        stop_updates1();
    }

    function update_footer(msg) {
        document.getElementById("log").textContent = msg + ' ' + updates_started + ' ' + getCookie("updates_started");
        document.getElementById("log").innerHTML += " " + toggle_link;
        document.getElementById("toggle").onclick = toggle_updates;
    }

    update_footer("Autoupdate waiting...");

    function linkify(text) {
        //var urlRegex = /(\b(https?|ftp|file):\/\/[-A-Z0-9+&@#\/%?=~_|!:,.;]*[-A-Z0-9+&@#\/%=~_|])/ig;
        var urlRegex = /(\b(preview)[-A-Z0-9+&@#\/%?=~_|!:,.;]*[-A-Z0-9+&@#\/%=~_|])/ig;
        var links = text.match(urlRegex);
        return links;
    }

    function check_link(link) {
        return link.search("fname=") >= 0;
    }

    function proc_responce(resp_txt){
        var links = linkify(resp_txt);
        var pic_link = links.find(check_link);

        var picname_re = /fname=([-_A-Z0-9]+)\.jpg/ig;
        var our_picname = document.getElementById("srcPic").src.match(picname_re)[0];
        var new_picname = pic_link.match(picname_re)[0];
        if (our_picname != new_picname){
            location.assign('http://ezshare.card/' + pic_link);
        }

    }

    function process_error(response) {
        update_footer("Autoupdate not connected... " + counter.toString());
        if (counter < errors_limit){
            setTimeout(check_updates, check_interval);
        }
        else {
            //updates_started = false; //???
            update_footer("Autoupdate stoped (no connection)");
            stop_updates1()
        }
        counter += 1;
    }

    function check_updates() {

        if (!updates_started) {
            counter = wait_limit + 1;
        }

        GM.xmlHttpRequest({
            method: "GET",
            //url: "http://127.0.0.1:5000/st/cat.html/",
            url: "http://ezshare.card/photo?vtype=0&fdir=101EOS5D&dirpage=1&ftype=0&devw=320&devh=356&folderFlag=0",
            onload: function(response) {
                proc_responce(response.responseText);

                update_footer("Autoupdate waiting... " + counter.toString());
                if (counter < wait_limit) {
                    setTimeout(check_updates, check_interval);
                }
                else {
                    //updates_started = true;
                    update_footer("Autoupdate stoped (no activity)");
                    stop_updates1();
                }
                counter += 1;
            },
            onerror: process_error,
            onabort: process_error,
            ontimeout: process_error
        });

    }

    //check_updates();

})();