const httpServer = require("http").createServer(); const io = require("socket.io")(httpServer, {cors: {origin: "*"}}); const rooms = {}; /** * Generates a random room code. * @returns {*|string} A random room code. */ const generateRoomCode = () => { const code = Math.random().toString(36).substring(2, 6).toUpperCase(); return rooms[code] ? generateRoomCode() : code; } /** * Returns the room code of the room the socket is in. * @param socketId The socket id of the socket. * @returns {string} The room code of the room the socket is in. */ const getRoomCodeBySocketId = (socketId) => { return Object.keys(rooms).find((code) => rooms[code].host === socketId || rooms[code].players.some((player) => player.id === socketId)); } /** * Returns the name of the player with the given socket id in the given room. * @param socketId The socket id of the player. * @param roomCode The room code of the room the player is in. * @returns {*|null} The name of the player with the given socket id in the given room. */ const getPlayerName = (socketId, roomCode) => { const player = rooms[roomCode].players.find((player) => player.id === socketId); return player ? player.name : null; } io.on("connection", (socket) => { socket.on("CREATE_ROOM", (data, callback = () => {}) => { if (getRoomCodeBySocketId(socket.id)) { callback(false); return; } const code = generateRoomCode(); rooms[code] = {host: socket.id, players: []}; callback({code}); console.log(`Room ${code} created by ${socket.id}.`); socket.join(code); }); socket.on("JOIN_ROOM", (data, callback = () => {}) => { if (getRoomCodeBySocketId(socket.id)) { callback(false); return; } const {code, name} = data; if (!code || !name) { callback(false); return; } if (rooms[code]) { socket.join(code); rooms[code].players.push({id: socket.id, name}); io.to(rooms[code].host).emit("JOINED", {id: socket.id, name}); callback(true); } else { callback(false); } }); socket.on("SUBMISSION_READY", (data, callback = () => {}) => { const roomCode = getRoomCodeBySocketId(socket.id); io.to(roomCode).emit("SUBMISSION_READY"); callback(true); }); socket.on("SUBMIT", (data, callback = () => {}) => { const {price, amount} = data; if (price === undefined || amount === undefined) { callback(false); return; } if (price < 0 || price > 10000 || amount < 0 || amount > 20) { callback(false); return; } const roomCode = getRoomCodeBySocketId(socket.id); const playerName = getPlayerName(socket.id, roomCode); io.to(rooms[roomCode].host).emit("RECEIVED", {id: socket.id, name: playerName, price, amount}); callback(true); }); socket.on("UPDATE_CAPITAL", (data, callback = () => {}) => { const {id, capital} = data; if (!id || capital === undefined) { callback(false); return; } io.to(id).emit("CAPITAL", {capital}); if (capital < 5000) { socket.emit("LEFT", {id: socket.id}); io.sockets.sockets.get(id).disconnect(); } callback(true); }); socket.conn.on("close", () => { const roomCode = getRoomCodeBySocketId(socket.id); if (!roomCode) return; rooms[roomCode].players = rooms[roomCode].players.filter((player) => player.id !== socket.id); if (rooms[roomCode].host === socket.id) { for (const player of rooms[roomCode].players) io.sockets.sockets.get(player.id).disconnect(); delete rooms[roomCode]; } else { io.to(rooms[roomCode].host).emit("LEFT", {id: socket.id}); } }); }); httpServer.listen(3000, () => { console.log("listening on *:3000"); });