main.js

// Electron's entry point (web-based RIDE doesn't load it)
const rq = require;
const fs = rq('fs');
const ps = process;
const el = rq('electron');
const elm = rq('@electron/remote/main');
const D = {};

elm.initialize();
// Detect platform: https://nodejs.org/api/process.html#process_process_platform
// https://stackoverflow.com/questions/19877924/what-is-the-list-of-possible-values-for-navigator-platform-as-of-today
D.win = /^win/i.test(ps.platform);
D.mac = ps.platform === 'darwin';

if (ps.env.spectron_temp_dir) {
  el.app.setPath('userData', ps.env.spectron_temp_dir);
}

const winstate = ps.env.RIDE_CONF || 'winstate';

// build db file path & set up empty db
const dbf = `${el.app.getPath('userData')}/${winstate}.json`; // json "database" file for storing preferences
let db = {};
// try reading the preferences
try {
  if (fs.existsSync(dbf))db = JSON.parse(fs.readFileSync(dbf, 'utf8'));
} catch (e) { console.error(e); }

let tid;
let dx = 0;
let dy = 0; // used to correct for bad coords misreported by Electron (NW.js has the same problem)

const h = { theme: 'light' };
global.winstate = h;
const svNow = () => { // save now
  tid = 0;
  try {
    const { elw } = global;
    const bounds = elw.getBounds();
    h.main = [bounds.x - dx, bounds.y - dy, bounds.width, bounds.height, elw.isMaximized()];
    h.devTools = elw.isDevToolsOpened();
    fs.writeFileSync(dbf, JSON.stringify(h));
  } catch (e) { console.error(e); }
};

const sv = () => { if (!tid)tid = setTimeout(svNow, 2000); }; // save (throttled)


el.app.on('ready', () => {
  // initialise variables
  let x; let y;
  let width; let height;

  // if we have a position saved try and restore it
  if (db.main) {
    // get co-ordinates & bounds
    [x, y, width, height] = db.main;
    // determine an appropriate screen
    const b = el.screen.getDisplayMatching({
      x, y, width, height,
    }).bounds;

    const vw = Math.max(0, Math.min(x + width, b.x + b.width) - Math.max(x, b.x));
    const vh = Math.max(0, Math.min(y + height, b.y + b.height) - Math.max(y, b.y));

    if (width * height > 2 * vw * vh) {
      // saved window position is now mostly off screen
      x = null;
      y = null;
      width = Math.min(width, b.width);
      height = Math.min(height, b.height);
    }
  }

  // create an electron renderer
  global.elw = new el.BrowserWindow({
    x,
    y,
    width,
    height,
    show: 0,
    ...(!D.win && !D.mac && { icon: `${__dirname}/D.png` }),
    backgroundColor: '#7688d9',
    webPreferences: {
      contextIsolation: false,
      enableRemoteModule: true,
      nodeIntegration: true,
    },
  });
  elm.enable(global.elw.webContents);
  el.Menu.setApplicationMenu(null);

  let w = global.elw;
  const showMB = (f) => {
    w.setMenuBarVisibility(!!f);
    w.setAutoHideMenuBar(!f);
  };
  if (db.main && db.main[4])w.maximize();
  w.loadURL(`file://${__dirname}/index.html`);
  w.on('move', sv).on('resize', sv).on('maximize', sv).on('unmaximize', sv)
    .on('enter-full-screen', () => showMB(0))
    .on('leave-full-screen', () => showMB(1))
    .on('close', () => {
      if (tid)clearTimeout(tid);
      svNow();
    })
    .on('closed', () => {
      global.elw = 0;
      w = 0;
    })
    .on('show', () => {
      if (x) {
        const q = w.getPosition();
        dx = q[0] - x;
        dy = q[1] - y;
      }
    })
    .on('ready-to-show', w.show);

  if (db.devTools)w.webContents.openDevTools();

  if (process.argv.constructor === Array && process.argv.includes('DEV_STYLE')) {
    const { client } = rq('electron-connect');
    const c = client.create(w, { sendBounds: false });
    c.on('reboot', () => {
      w.close();
      el.app.relaunch();
    });
    c.on('css_update', () => {
      // define the reload function that hacks in the new styles
      const reloadFn = `() => {
        [...document.getElementsByClassName('theme')].forEach(t => t.replaceWith(t));
      }`;
      w.webContents.executeJavaScript(`(${reloadFn})()`);
    });
  }
});

el.app.on('window-all-closed', () => { el.app.quit(); });
el.app.on('will-finish-launching', () => {
  el.app.on('open-file', (event, path) => {
      global.open_file = path;
  });
});
global.js = (i, x) => el.BrowserWindow.fromId(i).webContents.executeJavaScript(x);