src/middleware/auth.ts

import jwt from 'jsonwebtoken';
import { Request, Response, NextFunction } from 'express';

export interface AuthenticatedRequest extends Request {
  user?: {
    userId: number;
    tenantId: number;
  };
}

export const authenticateToken = (req: AuthenticatedRequest, res: Response, next: NextFunction) => {
  const authHeader = req.headers['authorization'];
  const token = authHeader && authHeader.split(' ')[1]; // Bearer TOKEN

  if (!token) {
    return res.status(401).json({ error: 'Access token required' });
  }

  try {
    const decoded = jwt.verify(token, process.env.JWT_SECRET!) as any;
    req.user = {
      userId: decoded.userId,
      tenantId: decoded.tenantId
    };
    next();
  } catch (error) {
    return res.status(403).json({ error: 'Invalid or expired token' });
  }
};