start support for songs

socketio.js

@@ -0,0 +1,61 @@
+// Server-side code
+const express = require('express');
+const http = require('http');
+const socketIO = require('socket.io');
+
+const app = express();
+const server = http.createServer(app);
+const io = socketIO(server);
+
+let interval;
+let tempo = 120; // Initial tempo (beats per minute)
+let startTime; // Start time of the metronome
+
+io.on('connection', (socket) => {
+  console.log('A client connected');
+
+  socket.on('start', () => {
+    console.log('Metronome started');
+    startTime = Date.now(); // Set the start time
+
+    // Calculate the delay between each beat based on the tempo
+    const delay = (60 / tempo) * 1000;
+
+    // Send a beat event to all connected clients at the specified interval
+    interval = setInterval(() => {
+      const elapsedTime = Date.now() - startTime;
+      io.emit('beat', elapsedTime);
+    }, delay);
+  });
+
+  socket.on('stop', () => {
+    console.log('Metronome stopped');
+    clearInterval(interval);
+  });
+
+  socket.on('tempo', (newTempo) => {
+    console.log(`Tempo set to ${newTempo} BPM`);
+    tempo = newTempo;
+
+    // If the metronome is already running, restart it with the new tempo
+    if (interval) {
+      clearInterval(interval);
+      const delay = (60 / tempo) * 1000;
+      interval = setInterval(() => {
+        const elapsedTime = Date.now() - startTime;
+        io.emit('beat', elapsedTime);
+      }, delay);
+    }
+  });
+
+  socket.on('disconnect', () => {
+    console.log('A client disconnected');
+    clearInterval(interval);
+  });
+});
+
+server.listen(3000, () => {
+  console.log('Server is running on port 3000');
+});
+
+return io;