server.js

const express = require('express');
const WebSocket = require('ws');
const http = require('http');
const cors = require('cors');

// Initialize express app
const app = express();
const server = http.createServer(app);
const wss = new WebSocket.Server({ server });

// Middleware
app.use(cors({
    origin: ['https://load-testing-frontend-jvh6pw9qc-suryas-projects-d138d765.vercel.app', 'http://localhost:3000'],
    methods: ['GET', 'POST'],
    credentials: true
  }));
app.use(express.json());

// Store active load test sessions
const activeTests = new Map();

// WebSocket connection handling
wss.on('connection', (ws) => {
    console.log('New client connected');

    ws.on('message', (message) => {
        const data = JSON.parse(message);
        
        switch(data.type) {
            case 'START_TEST':
                handleTestStart(ws, data.payload);
                break;
            case 'STOP_TEST':
                handleTestStop(ws, data.payload);
                break;
            default:
                console.log('Unknown message type:', data.type);
        }
    });

    ws.on('close', () => {
        console.log('Client disconnected');
    });
});

// API Routes
app.post('/api/test/create', (req, res) => {
    const testConfig = req.body;
    const testId = Date.now().toString();
    
    activeTests.set(testId, {
        config: testConfig,
        status: 'created',
        metrics: {
            requestCount: 0,
            responseTime: [],
            errors: []
        }
    });
    
    res.json({ testId, status: 'created' });
});

app.get('/api/test/:testId', (req, res) => {
    const { testId } = req.params;
    const test = activeTests.get(testId);
    
    if (!test) {
        return res.status(404).json({ error: 'Test not found' });
    }
    
    res.json(test);
});

// Helper functions
function handleTestStart(ws, payload) {
    const test = activeTests.get(payload.testId);
    if (test) {
        test.status = 'running';
        // Here we'll later add logic to spawn load test workers
        broadcastTestStatus(payload.testId);
    }
}

function handleTestStop(ws, payload) {
    const test = activeTests.get(payload.testId);
    if (test) {
        test.status = 'stopped';
        broadcastTestStatus(payload.testId);
    }
}

function broadcastTestStatus(testId) {
    const test = activeTests.get(testId);
    wss.clients.forEach(client => {
        if (client.readyState === WebSocket.OPEN) {
            client.send(JSON.stringify({
                type: 'TEST_UPDATE',
                payload: { testId, ...test }
            }));
        }
    });
}

const PORT = process.env.PORT || 3001;
server.listen(PORT, () => {
    console.log(`Server running on port ${PORT}`);
});