server/src/middleware/auth.ts

import { Request, Response, NextFunction } from 'express';
import jwt from 'jsonwebtoken';
import { config } from '../config';
import { User } from '../models';

export interface AuthRequest extends Request {
    userId?: string;
    userRole?: string;
}

export const authMiddleware = async (
    req: AuthRequest,
    res: Response,
    next: NextFunction
): Promise<void> => {
    try {
        const authHeader = req.headers.authorization;
        if (!authHeader || !authHeader.startsWith('Bearer ')) {
            res.status(401).json({ error: 'Access denied. No token provided.' });
            return;
        }

        const token = authHeader.split(' ')[1];
        const decoded = jwt.verify(token, config.jwt.secret) as {
            userId: string;
            role: string;
        };

        const user = await User.findById(decoded.userId);
        if (!user) {
            res.status(401).json({ error: 'Invalid token. User not found.' });
            return;
        }

        req.userId = decoded.userId;
        req.userRole = decoded.role;
        next();
    } catch (error) {
        res.status(401).json({ error: 'Invalid or expired token.' });
    }
};

export const adminMiddleware = (
    req: AuthRequest,
    res: Response,
    next: NextFunction
): void => {
    if (req.userRole !== 'admin') {
        res.status(403).json({ error: 'Admin access required.' });
        return;
    }
    next();
};