Update server.js

server.js

@@ -1,5 +1,4 @@
 
-// ... existing imports
 const { 
     School, User, Student, Course, Score, ClassModel, SubjectModel, ExamModel, ScheduleModel,
     ConfigModel, NotificationModel, GameSessionModel, StudentRewardModel, LuckyDrawConfigModel, GameMonsterConfigModel, GameZenConfigModel,
@@ -7,13 +6,17 @@ const {
     WishModel, FeedbackModel
 } = require('./models');
 
-// Initialize Gemini
-const { GoogleGenAI, Type, Modality } = require("@google/genai");
-// Note: GoogleGenAI client is initialized inside requests to use process.env.API_KEY dynamically if needed, 
-// but here we follow standard pattern.
-const ai = new GoogleGenAI({ apiKey: process.env.API_KEY });
+// Initialize Gemini via Dynamic Import (Helper)
+// @google/genai is an ESM-only package, so we cannot use require() in this CommonJS file.
+let genAIContext = null;
+async function getGenAI() {
+    if (genAIContext) return genAIContext;
+    const { GoogleGenAI, Type, Modality } = await import("@google/genai");
+    const ai = new GoogleGenAI({ apiKey: process.env.API_KEY });
+    genAIContext = { ai, Type, Modality };
+    return genAIContext;
+}
 
-// ... (existing setup code, middleware, connectDB, helpers)
 const express = require('express');
 const mongoose = require('mongoose');
 const cors = require('cors');
@@ -107,6 +110,9 @@ app.post('/api/ai/chat', async (req, res) => {
     const { text, audio } = req.body; // audio is base64 string
     
     try {
+        // Dynamically import AI
+        const { ai, Modality } = await getGenAI();
+
         const parts = [];
         if (audio) {
             parts.push({
@@ -167,6 +173,9 @@ app.post('/api/ai/evaluate', async (req, res) => {
     if (!question || !audio) return res.status(400).json({ error: 'Missing question or audio' });
 
     try {
+        // Dynamically import AI
+        const { ai, Type } = await getGenAI();
+
         // Evaluate using Multimodal capability
         const response = await ai.models.generateContent({
             model: 'gemini-2.5-flash-lite',
@@ -570,4 +579,4 @@ app.delete('/api/attendance/calendar/:id', async (req, res) => { await SchoolCal
 app.post('/api/batch-delete', async (req, res) => { if(req.body.type==='student') await Student.deleteMany({_id:{$in:req.body.ids}}); if(req.body.type==='score') await Score.deleteMany({_id:{$in:req.body.ids}}); res.json({}); });
 
 app.get('*', (req, res) => { res.sendFile(path.join(__dirname, 'dist', 'index.html')); });
-app.listen(PORT, () => console.log(`🚀 Server running on port ${PORT}`));
+app.listen(PORT, () => console.log(`🚀 Server running on port ${PORT}`));