const config = require('../../config');
const { getRoomPrice } = config;

let db;

function init(database) {
    db = database;
}

function calculateBasePrice(roomType, checkin, checkout) {
    const pricePerNight = getRoomPrice(roomType);
    const nights = config.calculateNights(checkin, checkout);
    return pricePerNight * nights;
}

function validatePromocode(promocode, callback) {
    if (!promocode) return callback(null, null);
    const now = new Date().toISOString();
    db.get(`SELECT * FROM promocodes WHERE code = ? AND is_active = 1`, [promocode], (err, row) => {
        if (err || !row) return callback(null, null);
        if (row.valid_from && row.valid_from > now) return callback(null, null);
        if (row.valid_to && row.valid_to < now) return callback(null, null);
        if (row.valid_days) {
            const createdDate = new Date(row.created_at);
            const expireDate = new Date(createdDate.getTime() + row.valid_days * 24 * 60 * 60 * 1000);
            if (expireDate < new Date()) return callback(null, null);
        }
        callback(null, row);
    });
}

function createBooking(req, res) {
    const { name, phone, adults, children, checkin, checkout, wishes, room, room_id, promocode } = req.body;
    if (!name || !phone || !adults || !checkin || !checkout) {
        return res.status(400).json({ error: 'Missing required fields' });
    }
    const basePrice = calculateBasePrice(room, checkin, checkout) * (parseInt(adults) || 1);
    validatePromocode(promocode, (err, promo) => {
        if (err) return res.status(500).json({ error: 'Database error' });
        let discountPercent = 0;
        let promocodeId = null;
        if (promo) {
            discountPercent = promo.discount_percent;
            promocodeId = promo.id;
        }
        const safeBasePrice = basePrice || 0;
        const discountAmount = Math.round(safeBasePrice * discountPercent / 100);
        const totalPrice = safeBasePrice - discountAmount;
        const roomIdValue = room_id ? parseInt(room_id) : null;
        const stmt = db.prepare(`INSERT INTO bookings (name, phone, adults, children, checkin_date, checkout_date, wishes, status, room_type, room_id, base_price, discount_percent, discount_amount, total_price, promocode_id)
                                 VALUES (?, ?, ?, ?, ?, ?, ?, 'новая', ?, ?, ?, ?, ?, ?, ?)`);
        stmt.run(name, phone, parseInt(adults), parseInt(children || 0), checkin, checkout, wishes || null, room || null, roomIdValue,
            safeBasePrice || null, discountPercent || 0, discountAmount || 0, totalPrice || null, promocodeId, function(err) {
            if (err) {
                console.error(err);
                return res.status(500).json({ error: 'Database error' });
            }
            res.status(201).json({ id: this.lastID, message: 'Booking saved', base_price: safeBasePrice, discount_percent: discountPercent, discount_amount: discountAmount, total_price: totalPrice });
        });
        stmt.finalize();
    });
}

function getBookings(req, res) {
    const providedKey = req.headers['x-api-key'];
    if (!providedKey) return res.status(401).json({ error: 'Invalid or missing API key' });
    const API_KEY = process.env.HOTEL777KEY;
    if (providedKey !== API_KEY) return res.status(401).json({ error: 'Invalid or missing API key' });
    db.all(`SELECT b.*, p.code as promocode_code FROM bookings b
            LEFT JOIN promocodes p ON b.promocode_id = p.id
            ORDER BY b.checkin_date ASC`, (err, rows) => {
        if (err) {
            console.error(err);
            return res.status(500).json({ error: 'Database error' });
        }
        res.json(rows);
    });
}

function getBookingHistory(req, res) {
    const bookingId = parseInt(req.params.id);
    db.all(`SELECT id, booking_id, user_id, user_login, field, old_value, new_value, created_at
            FROM booking_history WHERE booking_id = ? ORDER BY created_at DESC`, [bookingId], (err, rows) => {
        if (err) return res.status(500).json({ error: 'Database error' });
        res.json(rows);
    });
}

function logHistory(bookingId, userId, userLogin, field, oldValue, newValue) {
    db.run(`INSERT INTO booking_history (booking_id, user_id, user_login, field, old_value, new_value) VALUES (?, ?, ?, ?, ?, ?)`,
        [bookingId, userId, userLogin, field, oldValue, newValue], (err) => {
            if (err) console.error('History log error:', err);
        });
}

function setupRoutes(app, authenticateToken, requireAdmin) {
    app.post('/api/bookings', createBooking);
    app.get('/api/bookings', getBookings);
    app.get('/api/admin/bookings/:id/history', authenticateToken, getBookingHistory);
}

module.exports = { init, setupRoutes, validatePromocode, logHistory, calculateBasePrice };