_boot.js

const signale = require("signale");
const {app, BrowserWindow, dialog, shell} = require("electron");

process.on("uncaughtException", e => {
    signale.fatal(e);
    dialog.showErrorBox("eEDEX-UI failed to launch", e.message || "Cannot retrieve error message.");
    if (tty) {
        tty.close();
    }
    if (extraTtys) {
        Object.keys(extraTtys).forEach(key => {
            if (extraTtys[key] !== null) {
                extraTtys[key].close();
            }
        });
    }
    process.exit(1);
});

signale.start(`Starting eDEX-UI v${app.getVersion()}`);
signale.info(`With Node ${process.versions.node} and Electron ${process.versions.electron}`);
signale.info(`Renderer is Chrome ${process.versions.chrome}`);
signale.time("Startup");

const electron = require("electron");
const ipc = electron.ipcMain;
const path = require("path");
const url = require("url");
const fs = require("fs");
const clip = require("clipboardy");
const Terminal = require("./classes/terminal.class.js").Terminal;

ipc.on("log", (e, type, content) => {
    signale[type](content);
});

var win, tty, extraTtys;
const settingsFile = path.join(electron.app.getPath("userData"), "settings.json");
const themesDir = path.join(electron.app.getPath("userData"), "themes");
const innerThemesDir = path.join(__dirname, "assets/themes");
const kblayoutsDir = path.join(electron.app.getPath("userData"), "keyboards");
const innerKblayoutsDir = path.join(__dirname, "assets/kb_layouts");
const fontsDir = path.join(electron.app.getPath("userData"), "fonts");
const innerFontsDir = path.join(__dirname, "assets/fonts");

// Fix userData folder not setup on Windows
try {
    fs.mkdirSync(electron.app.getPath("userData"));
    signale.info(`Created config dir at ${electron.app.getPath("userData")}`);
} catch(e) {
    signale.info(`Base config dir is ${electron.app.getPath("userData")}`);
}
// Create default settings file
if (!fs.existsSync(settingsFile)) {
    fs.writeFileSync(settingsFile, JSON.stringify({
        shell: (process.platform === "win32") ? "powershell.exe" : "bash",
        cwd: electron.app.getPath("userData"),
        keyboard: "en-US",
        theme: "tron",
        audio: false
    }, 4));
}

// Copy default themes & keyboard layouts & fonts
try {
    fs.mkdirSync(themesDir);
} catch(e) {
    // Folder already exists
}
fs.readdirSync(innerThemesDir).forEach((e) => {
    fs.writeFileSync(path.join(themesDir, e), fs.readFileSync(path.join(innerThemesDir, e), {encoding:"utf-8"}));
});
try {
    fs.mkdirSync(kblayoutsDir);
} catch(e) {
    // Folder already exists
}
fs.readdirSync(innerKblayoutsDir).forEach((e) => {
    fs.writeFileSync(path.join(kblayoutsDir, e), fs.readFileSync(path.join(innerKblayoutsDir, e), {encoding:"utf-8"}));
});
try {
    fs.mkdirSync(fontsDir);
} catch(e) {
    // Folder already exists
}
fs.readdirSync(innerFontsDir).forEach((e) => {
    fs.writeFileSync(path.join(fontsDir, e), fs.readFileSync(path.join(innerFontsDir, e)));
});

function createWindow(settings) {
    signale.info("Creating window...");

    let display;
    if (!isNaN(settings.monitor)) {
        display = electron.screen.getAllDisplays()[settings.monitor] || electron.screen.getPrimaryDisplay();
    } else {
        display = electron.screen.getPrimaryDisplay();
    }
    let {x, y, width, height} = display.bounds;
    width++; height++;
    win = new BrowserWindow({
        title: "eDEX-UI",
        x,
        y,
        width,
        height,
        show: false,
        resizable: true,
        movable: settings.allowWindowed || false,
        fullscreen: true,
        autoHideMenuBar: true,
        frame: settings.allowWindowed || false,
        backgroundColor: '#000000',
        webPreferences: {
            devTools: true,
            backgroundThrottling: false,
            webSecurity: true,
            nodeIntegration: true,
            allowRunningInsecureContent: false,
            experimentalFeatures: settings.experimentalFeatures || false
        }
    });

    win.loadURL(url.format({
        pathname: path.join(__dirname, 'ui.html'),
        protocol: 'file:',
        slashes: true
    }));

    win.once("ready-to-show", () => {
        signale.complete("Frontend window is up!");
        win.show();
        if (!settings.allowWindowed) {
            win.setResizable(false);
        }
    });

    signale.watch("Waiting for frontend connection...");
}

app.on('ready', () => {
    signale.pending(`Loading settings file...`);
    let settings = require(settingsFile);
    signale.success(`Settings loaded!`);

    if (!require("fs").existsSync(settings.cwd)) throw new Error("Configured cwd path does not exist.");

    signale.pending(`Creating new terminal process on port ${settings.port || '3000'}`);
    tty = new Terminal({
        role: "server",
        shell: settings.shell.split(" ")[0],
        params: settings.shell.split(" ").splice(1),
        cwd: settings.cwd,
        env: settings.env,
        port: settings.port || 3000
    });
    signale.success(`Terminal back-end initialized!`);
    tty.onclosed = (code, signal) => {
        tty.ondisconnected = () => {};
        signale.complete("Terminal exited", code, signal);
        app.quit();
    };
    tty.onopened = () => {
        signale.success("Connected to frontend!");
        signale.timeEnd("Startup");
    };
    tty.onresized = (cols, rows) => {
        signale.info("Resized TTY to ", cols, rows);
    };
    tty.ondisconnected = () => {
        signale.error("Lost connection to frontend");
        signale.watch("Waiting for frontend connection...");
    };

    // Clipboard backend access
    ipc.on("clipboard", (e, arg) => {
        switch(arg) {
            case "read":
                clip.read().then(text => {
                    e.sender.send("clipboard-reply", text);
                });
                break;
            default:
                throw new Error("Illegal clipboard access request");
        }
    });

    // Support for multithreaded systeminformation calls
    signale.pending("Starting multithreaded calls controller...");
    require("./_multithread.js");

    createWindow(settings);

    // Support for more terminals, used for creating tabs (currently limited to 4 extra terms)
    extraTtys = {};
    let basePort = settings.port || 3000;
    basePort = Number(basePort) + 2;

    for (let i = 0; i < 4; i++) {
        extraTtys[basePort+i] = null;
    }

    ipc.on("ttyspawn", (e, arg) => {
        let port = null;
        Object.keys(extraTtys).forEach(key => {
            if (extraTtys[key] === null && port === null) {
                extraTtys[key] = {};
                port = key;
            }
        });

        if (port === null) {
            signale.error("TTY spawn denied (Reason: exceeded max TTYs number)");
            e.sender.send("ttyspawn-reply", "ERROR: max number of ttys reached");
        } else {
            signale.pending(`Creating new TTY process on port ${port}`);
            let term = new Terminal({
                role: "server",
                shell: settings.shell.split(" ")[0],
                params: settings.shell.split(" ").splice(1),
                cwd: tty.tty._cwd || settings.cwd,
                env: settings.env,
                port: port
            });
            signale.success(`New terminal back-end initialized at ${port}`);
            term.onclosed = (code, signal) => {
                term.ondisconnected = () => {};
                term.wss.close();
                signale.complete(`TTY exited at ${port}`, code, signal);
                extraTtys[term.port] = null;
                delete term;
            };
            term.onopened = () => {
                signale.success(`TTY ${port} connected to frontend`);
            };
            term.onresized = () => {};
            term.ondisconnected = () => {
                term.onclosed = () => {};
                term.close();
                term.wss.close();
                extraTtys[term.port] = null;
                delete term;
            };

            extraTtys[port] = term;
            e.sender.send("ttyspawn-reply", "SUCCESS: "+port);
        }
    });

    // Backend support for theme and keyboard hotswitch
    let themeOverride = null;
    let kbOverride = null;
    ipc.on("getThemeOverride", (e, arg) => {
        e.sender.send("getThemeOverride", themeOverride);
    });
    ipc.on("getKbOverride", (e, arg) => {
        e.sender.send("getKbOverride", kbOverride);
    });
    ipc.on("setThemeOverride", (e, arg) => {
        themeOverride = arg;
    });
    ipc.on("setKbOverride", (e, arg) => {
        kbOverride = arg;
    });
});

app.on('web-contents-created', (e, contents) => {
    // Prevent creating more than one window
    contents.on('new-window', (e, url) => {
        e.preventDefault();
        shell.openExternal(url);
    });
    // Prevent loading something else than the UI
    contents.on('will-navigate', (e, url) => {
        if (url !== contents.getURL()) e.preventDefault();
    });
});

app.on('window-all-closed', () => {
    signale.info("All windows closed");
    app.quit();
});

app.on('before-quit', () => {
    tty.close();
    Object.keys(extraTtys).forEach(key => {
        if (extraTtys[key] !== null) {
            extraTtys[key].close();
        }
    });
    signale.complete("Shutting down...");
});