import { Router } from 'express';
import bcrypt from 'bcrypt';
import jwt from 'jsonwebtoken';
import { PrismaClient } from '@prisma/client';
import rateLimit from 'express-rate-limit';

const router = Router();
const prisma = new PrismaClient();
const JWT_SECRET = process.env.JWT_SECRET || 'fallback-secret-for-development-only';

const loginLimiter = rateLimit({
    windowMs: 15 * 60 * 1000, // 15 minutes
    max: 5, // Limit each IP to 5 failed login attempts per window
    message: { status: 'error', message: 'Too many login attempts, please try again later' },
    skipSuccessfulRequests: true,
});

// Check if setup is required (no users exist)
router.get('/auth/status', async (req, res) => {
    try {
        const userCount = await prisma.user.count();
        res.json({ setupRequired: userCount === 0 });
    } catch (error) {
        res.status(500).json({ status: 'error', message: 'Database error' });
    }
});

// Initial Setup (Only works if no users exist)
router.post('/auth/setup', async (req, res) => {
    try {
        const userCount = await prisma.user.count();
        if (userCount > 0) {
            return res.status(403).json({ status: 'error', message: 'Setup has already been completed' });
        }

        const { username, password } = req.body;
        if (!username || !password || password.length < 8) {
            return res.status(400).json({ status: 'error', message: 'Invalid username or password must be at least 8 characters' });
        }

        const hashedPassword = await bcrypt.hash(password, 10);
        const user = await prisma.user.create({
            data: { username, password: hashedPassword },
        });

        const token = jwt.sign({ id: user.id, username: user.username }, JWT_SECRET, { expiresIn: '7d' });
        res.json({ status: 'success', token, user: { id: user.id, username: user.username } });
    } catch (error) {
        res.status(500).json({ status: 'error', message: 'Failed to create user' });
    }
});

// Login
router.post('/auth/login', loginLimiter, async (req, res) => {
    try {
        const { username, password } = req.body;
        if (!username || !password) {
            return res.status(400).json({ status: 'error', message: 'Username and password required' });
        }

        const user = await prisma.user.findUnique({ where: { username } });
        if (!user) {
            return res.status(401).json({ status: 'error', message: 'Invalid credentials' });
        }

        const valid = await bcrypt.compare(password, user.password);
        if (!valid) {
            return res.status(401).json({ status: 'error', message: 'Invalid credentials' });
        }

        const token = jwt.sign({ id: user.id, username: user.username }, JWT_SECRET, { expiresIn: '7d' });
        res.json({ status: 'success', token, user: { id: user.id, username: user.username } });
    } catch (error) {
        res.status(500).json({ status: 'error', message: 'Login failed' });
    }
});

export default router;