export default async function ({ addon, console }) {

// TODO: test whether e.altKey is true in chromebooks when alt+clicking.

// If so, no timeout needed, similar to mute-project addon.

let global_fps = 30;

const vm = addon.tab.traps.vm;

let mode = false;

let monitorUpdateFixed = false;

const fastFlag = addon.self.dir + "/svg/fast-flag.svg";

let vanillaFlag = null;

while (true) {

let button = await addon.tab.waitForElement("[class^='green-flag_green-flag']", {

markAsSeen: true,

reduxEvents: ["scratch-gui/mode/SET_PLAYER", "fontsLoaded/SET_FONTS_LOADED", "scratch-gui/locales/SELECT_LOCALE"],

});

const updateFlag = () => {

if (!vanillaFlag) vanillaFlag = button.src;

button.src = mode ? fastFlag : vanillaFlag;

};

const changeMode = (_mode = !mode) => {

mode = _mode;

if (mode) {

setFPS(addon.settings.get("framerate"));

// monitor updates are throttled by default

// https://github.com/scratchfoundation/scratch-gui/blob/ba76db7/src/reducers/monitors.js

if (!monitorUpdateFixed) {

const originalListener = vm.listeners("MONITORS_UPDATE").find((f) => f.name === "onMonitorsUpdate");

if (originalListener) vm.removeListener("MONITORS_UPDATE", originalListener);

vm.on("MONITORS_UPDATE", (monitors) =>

addon.tab.redux.dispatch({

type: "scratch-gui/monitors/UPDATE_MONITORS",

monitors,

})

);

monitorUpdateFixed = true;

}

} else setFPS(30);

updateFlag();

};

const flagListener = (e) => {

if (addon.self.disabled) return;

const isAltClick = e.type === "click" && e.altKey;

const isChromebookAltClick = navigator.userAgent.includes("CrOS") && e.type === "contextmenu";

if (isAltClick || isChromebookAltClick) {

e.cancelBubble = true;

e.preventDefault();

changeMode();

}

};

button.addEventListener("click", flagListener);

button.addEventListener("contextmenu", flagListener);

const setFPS = (fps) => {

global_fps = addon.self.disabled ? 30 : fps;

clearInterval(vm.runtime._steppingInterval);

vm.runtime._steppingInterval = null;

vm.runtime.start();

};

addon.settings.addEventListener("change", () => {

if (vm.runtime._steppingInterval) {

setFPS(addon.settings.get("framerate"));

}

});

addon.self.addEventListener("disabled", () => changeMode(false));

vm.runtime.start = function () {

if (this._steppingInterval) return;

let interval = 1000 / global_fps;

this.currentStepTime = interval;

this._steppingInterval = setInterval(() => {

this._step();

}, interval);

this.emit("RUNTIME_STARTED");

};

updateFlag();

}

}