function test(e) {
    var node = e.target;
    if (
        e.screenY > node.boxObject.screenY + 5 ||
        node.nodeName != "tab" ||
        node == gBrowser.selectedTab
    ) return;
    gBrowser.selectedTab = node;
}
addEventListener("mousemove", test, false, gBrowser.mTabContainer);

const reloadInterval = 5000; //ms
const labelReload = "Перезагружать вкладку";
const labelStopReload = "Остановить перезагрузку вкладки";

const tabContextMenu = document.getElementById("tabContextMenu");
const insertPoint = document.getElementById("context_reloadTab");
const id = "context_reloadTab_interval";
const attr = "reload-interval-id";

var menuitem = document.createElement("menuitem");
menuitem.id = id;
const command = '\
    var tab = this.parentNode.triggerNode;\n\
    var interval = tab.getAttribute("' + attr + '");\n\
    if (interval) {\n\
        clearInterval(interval);\n\
        tab.removeAttribute("' + attr + '");\n\
    }\n\
    else {\n\
        var interval = setInterval(function() {\n\
            gBrowser.reloadTab(tab);\n\
        }, ' + reloadInterval + ');\n\
        tab.setAttribute("' + attr + '", interval);\n\
    }';
menuitem.setAttribute("oncommand", command);
    
function insertMenuitem(e) {
    if (e.target != tabContextMenu) return;

    var tab = tabContextMenu.triggerNode;
    var interval = tab.hasAttribute(attr);

    var label = interval ? labelStopReload : labelReload;
    menuitem.setAttribute("label", label);
    tabContextMenu.insertBefore(menuitem, insertPoint.nextSibling);
}
function removeMenuitem(e) {
    if (e.target != tabContextMenu) return;
    tabContextMenu.removeChild(menuitem);
}
addEventListener("popupshowing", insertMenuitem, false, tabContextMenu);
addEventListener("popuphiding", removeMenuitem, false, tabContextMenu);

const checkInterval = 1 * 60 * 1000; //ms
const labelReload = "Перезагружать вкладку";
const labelStopReload = "Остановить перезагрузку вкладки";
const noThrob = true;

const tabContextMenu = document.getElementById("tabContextMenu");
const insertPoint = document.getElementById("context_reloadTab");

var menuitem = document.createElement("menuitem");
menuitem.id = "context_reloadTab_interval";

function setThrobberState(tab, throb) {

    const on = "tab-throbber";
    const off = "tab-throbber-off"
    var throbber = 
        document.getAnonymousElementByAttribute(tab, "class", on) ||
        document.getAnonymousElementByAttribute(tab, "class", off);
    throbber.className = throb ? on : off;
}
function tick(tab) {

    var oldDocs = tab.docs;
    if (!oldDocs) return;
    tab.docs = {};
    function fillTabDocs(tab, win) {

        var frames = win.frames;
        var loc = frames.location;
        if (loc != "about:blank") {
            tab.docs[frames.location] = oldDocs[frames.location] || "";
        }
        if (!frames.length) return;
        for(var i = 0; i < frames.length; i++)
            fillTabDocs(tab, frames[i]);
    }
    var br = tab.linkedBrowser;
    if (!br) return;
    fillTabDocs(tab, br.contentWindow);
    for(var loc in tab.docs) sendRequest(tab, loc);
    setTimeout(tick, checkInterval, tab);
}
function sendRequest(tab, loc) {

    var req = new XMLHttpRequest();
    req.open("GET", loc, true);
    req.responseType = "text";
//    reg.timeout = Math.round(checkInterval / 2);
    req.onloadend = function() {

//        if (req.status != 200) return;
        var res = req.responseText;

        var old = tab.docs[loc];
        if (old && old != res) {
            var wn = tab.linkedBrowser.webNavigation;
            wn.reload(wn.LOAD_FLAGS_BYPASS_CACHE);
        }
        tab.docs[loc] = res;
    }
    req.channel.loadFlags |= req.channel.LOAD_BYPASS_CACHE;
    req.send(null);
}
function onCommand(e) {

    var tab = e.target.parentNode.triggerNode;
    if (tab.docs) {
        delete tab.docs;
        setThrobberState(tab, true);
        return;
    }
    if (noThrob) setThrobberState(tab, false);
    tab.docs = {};
    tick(tab);
}
function insertMenuitem(e) {

    if (e.target != tabContextMenu) return;
    var tab = tabContextMenu.triggerNode;
    var protocol = tab.linkedBrowser.contentDocument.location.protocol;
    if (protocol != "http:" && protocol != "https:") return;

    var label = tab.docs ? labelStopReload : labelReload;
    menuitem.setAttribute("label", label);
    tabContextMenu.insertBefore(menuitem, insertPoint.nextSibling);
}
function removeMenuitem(e) {
    if (e.target != tabContextMenu) return;
    try {
        tabContextMenu.removeChild(menuitem);
    } catch(ex) {}
}
addEventListener("popupshowing", insertMenuitem, false, tabContextMenu);
addEventListener("popuphiding", removeMenuitem, false, tabContextMenu);
addEventListener("command", onCommand, false, menuitem);

this.onDestroy = function(reason) {
    if (reason == "update" || reason == "delete") {
        Array.slice(gBrowser.tabs).forEach(function(tab) {
            delete tab.docs;
            setThrobberState(tab, true);
        });
    }
};

function reloader(e) {
    var tab = e.target;
    var br = tab.linkedBrowser;

    gBrowser.reloadTab(tab);
    br.addEventListener("DOMContentLoaded", function onLoad(e) {
        br.removeEventListener("DOMContentLoaded", onLoad, false);
        e.target.defaultView.scroll(0, 0);
    }, false);
}
function addListener(e) {
    if (e.button != 2 || e.target.nodeName != "tab") return;
    e.preventDefault();
    var tab = e.target;
    if (!tab.reloader) {
        addEventListener("TabSelect", reloader, false, tab);
        tab.reloader = true;
        return;
    }
    removeEventListener("TabSelect", reloader, false, tab);
    delete tab.reloader;
}
addEventListener("click", addListener, false, gBrowser.mTabContainer);