util.js

const { createConnection } = require('net');

const getIPCPath = (id) => {
    if (process.platform === 'win32') return `\\\\?\\pipe\\discord-ipc-${id}`;
    const prefix = process.env.XDG_RUNTIME_DIR || process.env.TMPDIR || process.env.TMP || process.env.TEMP || '/tmp';
    return `${prefix.replace(/\/$/, '')}/discord-ipc-${id}`;
};

module.exports = class Util {
    static encode(op, data) {
        data = JSON.stringify(data);
        const len = Buffer.byteLength(data);
        const packet = Buffer.alloc(8 + len);
        packet.writeInt32LE(op, 0);
        packet.writeInt32LE(len, 4);
        packet.write(data, 8, len);
        return packet;
    }

    static decode(socket, callback) {
        let working = { full: '', op: undefined };
        const packet = socket.read();
        if (!packet) return;

        let op = working.op;
        let raw;
        if (working.full === '') {
            op = working.op = packet.readInt32LE(0);
            raw = packet.slice(8, packet.readInt32LE(4) + 8);
        } else raw = packet.toString();

        try {
            let data = JSON.parse(working.full + raw);
            callback({op, data});
            working.full = '';
            working.op = undefined;
        } catch (err) { working.full += raw; }

        Util.decode(socket, callback);
    }

    static getIPC(id = 0) {
        return new Promise((resolve, reject) => {
            const path = getIPCPath(id);
            const onerror = () => {
                if (id < 10) resolve(util.getIPC(id + 1));
                else reject(new Error('[Discord RPC] Could not connect'));
            };
            const sock = createConnection(path, () => {
                sock.removeListener('error', onerror);
                resolve(sock);
            });
            sock.once('error', onerror);
        });
    }

//UUID function originally taken from https://github.com/discordjs/RPC/blob/master/src/util.js (MIT LICENSE)
    static uuid() {
        let uuid = '';
        for (let i = 0; i < 32; i += 1) {
            if (i === 8 || i === 12 || i === 16 || i === 20) uuid += '-';
            let n;
            if (i === 12) n = 4;
            else {
                const random = Math.random() * 16 | 0;
                if (i === 16) n = (random & 3) | 0;
                else n = random;
            }
            uuid += n.toString(16);
        }
        return uuid;
    }
};