import express from 'express';
import pool from '../database.js';

const router = express.Router();

// GET all users (without passwords)
router.get('/', async (req, res) => {
    try {
        const [rows] = await pool.execute(`
      SELECT id, username, name, role, permissions, is_active as isActive, created_at as createdAt 
      FROM users 
      ORDER BY created_at DESC
    `);

        // Parse permissions JSON
        const users = rows.map(user => ({
            ...user,
            permissions: user.permissions ? JSON.parse(user.permissions) : []
        }));

        res.json(users);
    } catch (error) {
        console.error('Error fetching users:', error);
        res.status(500).json({ error: 'Failed to fetch users' });
    }
});

// GET single user
router.get('/:id', async (req, res) => {
    try {
        const [rows] = await pool.execute(`
      SELECT id, username, name, role, permissions, is_active as isActive 
      FROM users 
      WHERE id = ?
    `, [req.params.id]);

        if (rows.length === 0) {
            return res.status(404).json({ error: 'User not found' });
        }

        const user = {
            ...rows[0],
            permissions: rows[0].permissions ? JSON.parse(rows[0].permissions) : []
        };

        res.json(user);
    } catch (error) {
        console.error('Error fetching user:', error);
        res.status(500).json({ error: 'Failed to fetch user' });
    }
});

// POST create user
router.post('/', async (req, res) => {
    try {
        const { username, password, name, role, permissions } = req.body;

        // Check if username already exists
        const [existing] = await pool.execute('SELECT id FROM users WHERE username = ?', [username]);
        if (existing.length > 0) {
            return res.status(400).json({ error: 'Username sudah digunakan' });
        }

        const permissionsJson = JSON.stringify(permissions || []);

        await pool.execute(`
      INSERT INTO users (username, password, name, role, permissions)
      VALUES (?, ?, ?, ?, ?)
    `, [username, password, name, role || 'staff', permissionsJson]);

        res.status(201).json({ status: 'success', message: 'User created' });
    } catch (error) {
        console.error('Error creating user:', error);
        res.status(500).json({ error: 'Failed to create user' });
    }
});

// PUT update user
router.put('/:id', async (req, res) => {
    try {
        const { username, password, name, role, permissions, isActive } = req.body;
        const permissionsJson = JSON.stringify(permissions || []);

        // Check if username already exists (for another user)
        const [existing] = await pool.execute(
            'SELECT id FROM users WHERE username = ? AND id != ?',
            [username, req.params.id]
        );
        if (existing.length > 0) {
            return res.status(400).json({ error: 'Username sudah digunakan oleh user lain' });
        }

        if (password && password.trim() !== '') {
            await pool.execute(`
        UPDATE users 
        SET username = ?, password = ?, name = ?, role = ?, permissions = ?, is_active = ?
        WHERE id = ?
      `, [username, password, name, role, permissionsJson, isActive !== false, req.params.id]);
        } else {
            await pool.execute(`
        UPDATE users 
        SET username = ?, name = ?, role = ?, permissions = ?, is_active = ?
        WHERE id = ?
      `, [username, name, role, permissionsJson, isActive !== false, req.params.id]);
        }

        res.json({ status: 'success', message: 'User updated' });
    } catch (error) {
        console.error('Error updating user:', error);
        res.status(500).json({ error: 'Failed to update user' });
    }
});

// DELETE user
router.delete('/:id', async (req, res) => {
    try {
        // Prevent deleting the last admin
        const [admins] = await pool.execute("SELECT id FROM users WHERE role = 'admin' AND is_active = TRUE");
        const [userToDelete] = await pool.execute('SELECT role FROM users WHERE id = ?', [req.params.id]);

        if (userToDelete.length > 0 && userToDelete[0].role === 'admin' && admins.length <= 1) {
            return res.status(400).json({ error: 'Tidak dapat menghapus admin terakhir' });
        }

        await pool.execute('DELETE FROM users WHERE id = ?', [req.params.id]);
        res.json({ status: 'success', message: 'User deleted' });
    } catch (error) {
        console.error('Error deleting user:', error);
        res.status(500).json({ error: 'Failed to delete user' });
    }
});

// POST login - verify credentials and return user with permissions
router.post('/login', async (req, res) => {
    try {
        const { username, password } = req.body;

        const [rows] = await pool.execute(`
      SELECT id, username, name, role, permissions, is_active as isActive 
      FROM users 
      WHERE username = ? AND password = ? AND is_active = TRUE
    `, [username, password]);

        if (rows.length === 0) {
            return res.status(401).json({ error: 'Username atau password salah' });
        }

        const user = {
            ...rows[0],
            permissions: rows[0].permissions ? JSON.parse(rows[0].permissions) : []
        };

        res.json({ status: 'success', user });
    } catch (error) {
        console.error('Error during login:', error);
        res.status(500).json({ error: 'Login failed' });
    }
});

export default router;