server.js

const express = require('express');
const helmet = require('helmet');
const cors = require('cors');
const rateLimit = require('express-rate-limit');
const cookieParser = require('cookie-parser');
const path = require('path');

const user_route = require('./routes/userRoutes');
const monitor_route = require('./routes/monitorRoutes');
const api_route = require('./routes/api');
const alert_route = require('./routes/alertRoutes');
const notification_channel_route = require('./routes/notificationChannelRoutes');
const swaggerUi = require('swagger-ui-express');
const swaggerSpec = require('./config/swagger');

const app = express();
const port = 3000;

// Trust proxies (rate limit / IP)
app.set('trust proxy', 1);

// Static files
app.use('/', express.static(path.join(__dirname, 'public')));

// Security middleware
app.use(helmet());
app.disable('x-powered-by');

// CORS configuration
app.use(
  cors({
    origin: ['http://127.0.0.1:5500', 'http://localhost:5173'], // Allowed frontend URLs
    methods: ['GET', 'POST', 'PUT', 'DELETE', 'OPTIONS'], // Allow preflight requests
    allowedHeaders: ['Content-Type', 'Authorization'],
    credentials: true,
  })
);

// Rate limiting
const limiter = rateLimit({
  windowMs: 15 * 60 * 1000,
  max: 800,
  message: 'Too many requests, try again later.',
});
app.use(limiter);

// Parsers
app.use(express.json());
app.use(cookieParser());
app.use(
  express.urlencoded({
    extended: true,
    inflate: true,
    limit: '1mb',
    parameterLimit: 5000,
    type: 'application/x-www-form-urlencoded',
  })
);

// API Docs
app.use('/api-docs', swaggerUi.serve, swaggerUi.setup(swaggerSpec));

// API Routes
app.use('/api', user_route);
app.use('/api', monitor_route);
app.use('/api', api_route);
app.use('/api', alert_route);
app.use('/api', notification_channel_route);

// Global error handler
app.use((err, req, res, next) => {
  console.error(err.stack);
  res.status(500).json({ message: 'Something went wrong!' });
});

module.exports = app;