2 files changed, 114 insertions, 0 deletions
diff --git a/graphs/js/advancedCommunication/client.js b/graphs/js/advancedCommunication/client.js
new file mode 100644
index 0000000..7c051a8
--- /dev/null
+++ b/graphs/js/advancedCommunication/client.js
@@ -0,0 +1,26 @@
+const WebSocket = require("ws");
+
+function addClient(userName) {
+    const socket = new WebSocket("ws://localhost:8080?username=" + userName);
+
+    socket.on("open", () => {
+        socket.send(userName + ": trying to establish connection");
+    });
+    socket.on("close", (code, reason) => {
+        console.log(
+            "<server to " +
+                userName +
+                ">: Connection has been closed: [" +
+                code +
+                "] " +
+                reason,
+        );
+    });
+    socket.on("message", (data) => {
+        console.log("<server to " + userName + ">: " + data);
+    });
+    return socket;
+}
+module.exports = {
+    addClient,
+};
diff --git a/graphs/js/advancedCommunication/server.js b/graphs/js/advancedCommunication/server.js
new file mode 100644
index 0000000..e642396
--- /dev/null
+++ b/graphs/js/advancedCommunication/server.js
@@ -0,0 +1,88 @@
+const WebSocket = require("ws");
+
+function startServer() {
+    const server = new WebSocket.Server({ port: 8080 });
+    const connections = new Array();
+    let maxID = 0;
+
+    console.log("Websocket server is running on port 8080.");
+    server.on("connection", (socket, request) => {
+        const userName = request.url.substring(11);
+
+        maxID++;
+        const current_connection = {
+            userName: userName,
+            id: maxID,
+            socket: socket,
+        };
+
+        socket.on("message", (data) => {
+            console.log("[" + current_connection.id + "] " + data);
+        });
+        socket.on("close", (code, reason) => {
+            console.log(
+                "[" +
+                    current_connection.id +
+                    "] Disconnected: [" +
+                    code +
+                    "] " +
+                    reason,
+            );
+            if (code !== 1008) {
+                for (const conn of connections) {
+                    if (conn.id !== current_connection.id) {
+                        conn.socket.send(userName + " disconnected");
+                    }
+                }
+
+                connections.splice(connections.indexOf(current_connection), 1);
+            }
+        });
+        for (const conn of connections) {
+            if (conn.userName === userName) {
+                socket.close(
+                    1008,
+                    'Username: "' + userName + '" is already taken',
+                );
+                return;
+            }
+        }
+
+        socket.send("Welcome " + userName);
+        connections.push(current_connection);
+        if (connections.length === 1) {
+            socket.send(userName + ", you are the only player connected");
+        } else {
+            socket.send(connections.length + " players are connected");
+        }
+
+        for (const conn of connections) {
+            if (conn.userName !== userName) {
+                conn.socket.send(userName + " connected");
+            }
+        }
+
+        if (connections.length < 4) {
+            for (const conn of connections) {
+                conn.socket.send(
+                    "Waiting for " +
+                        (4 - connections.length) +
+                        " other players to start the game",
+                );
+            }
+        } else {
+            for (const conn of connections) {
+                conn.socket.send(
+                    "Match will start soon, disconnecting " +
+                        conn.userName +
+                        " from the lobby",
+                );
+                conn.socket.close(1000, "Match is starting");
+            }
+        }
+    });
+    return server;
+}
+module.exports = {
+    startServer,
+};