const express = require('express');
const app = express();
const http = require('http');
const cors = require("cors");
const server = http.createServer(app);
const { Server } = require("socket.io");
const io = new Server(server, {
    cors: {
        origin: true,
    }
});

app.use(cors());

app.get('/', (req, res) => {
    res.sendFile(__dirname + '/index.html');
});

app.get("/cursor.svg", (req, res) => {
    res.sendFile(__dirname + "/cursor.svg");
});

let paths = {};

io.on('connection', (socket) => {
    console.log('a user connected');

    let userid = socket.id;

    // take stream of movement packet, append as necessary
    socket.on('movement', (data) => {
        if (paths[userid] === undefined) {
            paths[userid] = data;
        } else {
            paths[userid] = paths[userid].concat(data);
        }
        console.log(paths);

    });

    // send old paths to new user
    setInterval(() => {
        socket.emit('pathsync', paths);
    }, 1000);
});

server.listen(3000, () => {
    console.log('listening on *:3000');
});