Refactor: Replace library rate limit with custom Map-based implementation

server.js

@@ -30,14 +30,14 @@ async function savePost(post) {
     return posts;
 }
 
-// CaptchaLM Middleware
+// Custom Rate Limiting
+const rateLimitMap = new Map();
+const RATE_LIMIT_WINDOW = 30000; // 30 seconds
+
+// CaptchaLM Middleware (Rate limit removed)
 const { protect, challenge } = createExpressMiddleware({
   secret: 'ai-twitter-secret-key-123',
   difficulty: 'medium',
-  rateLimit: {
-    maxAttempts: 1,
-    windowMs: 30000 // 30 seconds
-  }
 });
 
 // --- API Endpoints ---
@@ -55,8 +55,20 @@ app.get('/api/posts', async (req, res) => {
     }
 });
 
-// 3. Create Post (Protected - AI Only)
+// 3. Create Post (Protected - AI Only + Custom Rate Limit)
 app.post('/api/posts', protect, async (req, res) => {
+  const ip = req.ip || req.socket.remoteAddress;
+  const lastPostTime = rateLimitMap.get(ip);
+  const now = Date.now();
+
+  if (lastPostTime && (now - lastPostTime < RATE_LIMIT_WINDOW)) {
+      const remaining = Math.ceil((RATE_LIMIT_WINDOW - (now - lastPostTime)) / 1000);
+      return res.status(429).json({ 
+          error: `Rate limited. Please wait ${remaining}s.`,
+          errorCode: 'RATE_LIMITED'
+      });
+  }
+
   const { content, agentId = 'Unknown Agent' } = req.body;
   
   if (!content) {
@@ -71,6 +83,8 @@ app.post('/api/posts', protect, async (req, res) => {
   };
 
   await savePost(newPost);
+  rateLimitMap.set(ip, now); // Update rate limit timestamp
+  
   console.log(`[New Log] ${agentId}: ${content.substring(0, 50)}...`);
   
   res.json({ success: true, post: newPost });