Store room FEN and leave rooms when back to home

backend/src/server.ts

@@ -6,11 +6,15 @@ import { generateRoomCode } from "./utils/calc.js";
 import dotenv from "dotenv";
 import { Server } from "socket.io";
 import { Chess } from "chess.js";
+import "./utils/globals.js";
 
 dotenv.config();
 
+globalThis.roomFen = new Map();
+
 const ENVIRONMENT = process.env.ENV || "dev";
 
+const START_FEN = new Chess().fen();
 const chess = new Chess();
 
 let expressApp = express();
@@ -56,17 +60,20 @@ io.on("connection", (socket) => {
       return;
     }
     socket.join(roomId);
+    globalThis.roomFen.set(roomId, START_FEN);
 
     if (io.sockets.adapter.rooms.get(roomId).size === 2)
-      io.to(roomId).emit(
-        "start",
-        "rnbqkbnr/pppppppp/8/8/8/8/PPPPPPPP/RNBQKBNR",
-        socket.id
-      );
+      io.to(roomId).emit("start", START_FEN, socket.id);
 
     callback("answer");
   });
 
+  socket.on("leave", () => {
+    socket.rooms.forEach((roomId) => {
+      if (roomId !== socket.id) socket.leave(roomId);
+    });
+  });
+
   socket.on("move", (move, callback) => {
     console.log(socket.id, move);
     const allowed = Math.random() < 0.7; //TODO LLM

backend/src/utils/globals.ts

@@ -0,0 +1 @@
+var roomFen: Map<string, string>;

frontend/src/Landing.tsx

@@ -1,6 +1,6 @@
 import { useCallback, useEffect, useRef, useState } from "react";
 import { Button, Grid, Header, Icon, Input } from "semantic-ui-react";
-import { createRoom, joinRoom } from "./utils/socket";
+import { createRoom, joinRoom, resetRoom } from "./utils/socket";
 
 export default function Landing({
   confirmedRoomCodeState,
@@ -48,6 +48,7 @@ export default function Landing({
               onClick={() => {
                 setConfirmedRoomCode("");
                 setRoomCode("");
+                resetRoom();
               }}
             >
               Back to Home

frontend/src/utils/socket.tsx

@@ -18,6 +18,10 @@ export async function joinRoom(roomId: string) {
   return response as boolean;
 }
 
+export function resetRoom() {
+  socket.emit("leave");
+}
+
 export async function move(move: string) {
   return (await socket.emitWithAck("move", move)) as string;
 }