import { Router } from 'express';
import pool from '../db.js';
import { randomUUID } from 'crypto';

const router = Router();

// GET /api/notifications/:userId
router.get('/:userId', async (req, res) => {
    try {
        const [rows] = await pool.query(
            'SELECT * FROM notifications WHERE user_id = ? ORDER BY created_at DESC LIMIT 50',
            [req.params.userId]
        );
        res.json(rows);
    } catch (err) {
        console.error('Fetch notifications error:', err);
        res.status(500).json({ error: 'Internal server error' });
    }
});

// PUT /api/notifications/:id/read
router.put('/:id/read', async (req, res) => {
    try {
        await pool.query('UPDATE notifications SET is_read = TRUE WHERE id = ?', [req.params.id]);
        res.json({ success: true });
    } catch (err) {
        console.error('Mark notification read error:', err);
        res.status(500).json({ error: 'Internal server error' });
    }
});

// Helper: Create notification and emit if possible
export async function createNotification(req, { userId, type, title, message, link }) {
    try {
        const id = randomUUID();
        await pool.query(
            'INSERT INTO notifications (id, user_id, type, title, message, link) VALUES (?, ?, ?, ?, ?, ?)',
            [id, userId, type, title, message, link]
        );

        if (req.io) {
            req.io.to(userId).emit('notification', {
                id, user_id: userId, type, title, message, link, is_read: false, created_at: new Date()
            });
        }
    } catch (err) {
        console.error('Create notification error:', err);
    }
}

export default router;