Game state persistency implemented. Game state is

now saved on page refresh.
The game state is stored on the server and when the user refreshes
the page the game state is fetched from the server on socket
re-connection

Next step:
stop user from making any move when the use is viewing past moves

backend/socket.js

@@ -2,15 +2,19 @@ const socket = require("socket.io");
 const { SOCKET_EVENTS } = require("./constants");
 const { CHESS_MOVE, CHESS_OPPONENT_MOVE, CONNECTION, JOIN_ROOM, JOIN_ROOM_ERROR, JOIN_ROOM_SUCCESS, ROOM_FULL } =
     SOCKET_EVENTS;
-// roomID => { timeLimit, players:[{username: {color}}] }
+// roomID => { timeLimit,gameHistory , players:[{username: {color}}] }
 let activeRooms = new Map();
 
 function createRoom(roomID, timeLimit) {
     console.log(roomID, "created");
-    activeRooms.set(roomID, { timeLimit, players: {} });
+    activeRooms.set(roomID, { timeLimit, players: {}, gameHistory: [] });
     console.log("Currently active rooms", activeRooms.size);
 }
 
+function getRoom(roomID) {
+    return activeRooms.get(roomID);
+}
+
 // structure of userDetails: {username,color}
 function addUserToRoom(roomID, userDetails) {
     console.log(userDetails);
@@ -57,7 +61,9 @@ function socketIOServerInit(server) {
                 if (result === JOIN_ROOM_SUCCESS) {
                     socket.join(roomID);
                     io.to(roomID).emit("new user joined the room");
-                    socket.emit(result); // room joined successfully
+                    console.log(data, "joined");
+                    let room = getRoom(roomID);
+                    socket.emit(result, room.gameHistory); // room joined successfully
                 } else {
                     socket.emit(result); // room is full
                 }
@@ -68,6 +74,8 @@ function socketIOServerInit(server) {
 
         socket.on(CHESS_MOVE, (roomID, moveData) => {
             console.log(moveData);
+            let room = activeRooms.get(roomID);
+            room.gameHistory.push(moveData);
             socket.to(roomID).emit(CHESS_OPPONENT_MOVE, moveData);
         });
     });