appRobotDriver/robot/fluidnc/FluidNCClient.js

const WebSocket = require("ws");
const EventEmitter = require("events");

class FluidNCClient extends EventEmitter {
    constructor(cfg) {
        super();

        this.host = cfg.host;
        this.port = cfg.port || 81;

        this.ws = null;
        this.reconnectDelay = 2000;

        this.connect();
    }

    connect() {
        const url = `ws://${this.host}:${this.port}`;
        console.log("[FluidNC] Connecting to:", url);

        this.ws = new WebSocket(url);

        this.ws.on("open", () => {
            console.log("[FluidNC] Connected (WS)");
        });

        this.ws.on("message", (msg) => {
            this.emit("message", msg.toString());
        });

        this.ws.on("close", () => {
            console.log("[FluidNC] Disconnected → retry");
            setTimeout(() => this.connect(), this.reconnectDelay);
        });

        this.ws.on("error", (err) => {
            console.log("[FluidNC] WS Error:", err.message);
        });
    }

    sendLine(cmd) {
        if (this.ws && this.ws.readyState === WebSocket.OPEN) {
            this.ws.send(cmd + "\n");
        }
    }

    requestStatus() {
        this.sendLine("?");
    }

    sendGcode(cmd) {
        this.sendLine(cmd);
    }

    onMessage(fn) {
        this.on("message", fn);
    }
}

module.exports = FluidNCClient;