server.js

const express = require('express');
const cors = require('cors');
const { CopilotRuntime, GoogleGenerativeAIAdapter, EmptyAdapter, copilotRuntimeNodeExpressEndpoint } = require('@copilotkit/runtime');

const app = express();
const port = process.env.PORT || 3001;

app.use(cors());
app.use(express.json());

// Add request logging middleware
app.use((req, res, next) => {
  if (req.path.startsWith('/api/copilotkit')) {
    console.log(`[${new Date().toISOString()}] ${req.method} ${req.path}`);
  }
  next();
});

// Initialize CopilotRuntime without any agents
// This ensures the serviceAdapter is used directly, not the agent system
const copilotRuntime = new CopilotRuntime({
  agents: {}, // Empty agents object to disable agent system
});

// Set Gemini API key as environment variable (required by the adapter)
process.env.GOOGLE_GENERATIVE_AI_API_KEY = process.env.GOOGLE_GENERATIVE_AI_API_KEY ;

// Choose adapter based on whether Gemini API key is configured
let adapter;
try {
  // Use GoogleGenerativeAIAdapter with Gemini
  adapter = new GoogleGenerativeAIAdapter({ 
    apiKey: process.env.GOOGLE_GENERATIVE_AI_API_KEY,
    model: process.env.GEMINI_MODEL || 'gemini-2.0-flash-exp' // Default Gemini model
  });
  console.log('Gemini adapter initialized with model:', process.env.GEMINI_MODEL || 'gemini-2.0-flash-exp');
} catch (error) {
  console.error('Error initializing Gemini adapter:', error.message);
  adapter = new EmptyAdapter();
}


// CopilotKit endpoint - handles chat completions
// Mount the endpoint handler - it will handle all routes under /api/copilotkit
app.use('/api/copilotkit', copilotRuntimeNodeExpressEndpoint({
  runtime: copilotRuntime,
  serviceAdapter: adapter,
  endpoint: '/api/copilotkit',
  basePath: '/api/copilotkit',
}));

// Health check endpoint
app.get('/api/health', (req, res) => {
  res.json({ status: 'ok' });
});

app.listen(port, () => {
  console.log(`CopilotKit server running on http://localhost:${port}`);
  console.log(`API endpoint: http://localhost:${port}/api/copilotkit`);
});