const crypto = require('crypto');
const db = require('../../../../models/migration');
require('dotenv').config();

class NotificationService {
    verifySignature(payload) {
        const { order_id, status_code, gross_amount, signature_key } = payload;
        const serverKey = process.env.MIDTRANS_SERVER_KEY;

        const data = order_id + status_code + gross_amount + serverKey;
        const hash = crypto.createHash('sha512').update(data).digest('hex');

        return hash === signature_key;
    }

    async processNotification(payload) {
        const { order_id, transaction_status, fraud_status } = payload;

        console.log(`[Notification] Processing Order ${order_id}: status=${transaction_status}, fraud=${fraud_status}`);

        try {
            let payment = await db.Payment.findOne({
                where: { external_id: order_id },
                order: [['created_at', 'DESC']]
            });

            let order = null;

            if (payment) {
                order = await db.Order.findByPk(payment.order_id);
            } else {
                order = await db.Order.findOne({ where: { orderID: order_id } });

                if (!order) {
                    order = await db.Order.findByPk(order_id);
                }
            }

            if (!order) {
                console.warn(`[Notification] Data Order/Payment untuk ID ${order_id} tidak ditemukan.`);
                return;
            }

            let orderPaymentStatus = 'PENDING';
            let orderStatus = order.status;
            let paymentRecordStatus = 'PENDING';

            if (transaction_status === 'settlement' || (transaction_status === 'capture' && fraud_status === 'accept')) {
                orderPaymentStatus = 'PAID';
                orderStatus = 'COMPLETED';
                paymentRecordStatus = 'SUCCESS';
            } else if (['deny', 'cancel', 'expire'].includes(transaction_status)) {
                orderPaymentStatus = 'REJECT';
                orderStatus = 'FAILED';
                paymentRecordStatus = 'FAILED';
            } else if (transaction_status === 'pending') {
                orderPaymentStatus = 'PENDING';
                paymentRecordStatus = 'PENDING';
            }

            if (order.payment_status === orderPaymentStatus && order.status === orderStatus) {
                console.log(`[Notification] Order ${order.id} sudah sinkron. Skip update.`);
                return;
            }

            await order.update({
                payment_status: orderPaymentStatus,
                status: orderStatus
            });

            if (!payment) {
                payment = await db.Payment.findOne({
                    where: { order_id: order.id },
                    order: [['created_at', 'DESC']]
                });
            }

            if (payment) {
                await payment.update({
                    status: paymentRecordStatus,
                    response_data: JSON.stringify(payload)
                });
            }

            console.log(`[Notification] SUCCESS: Order ${order.id} updated to ${orderStatus}, Payment updated to ${paymentRecordStatus}`);
        } catch (error) {
            console.error(`[Notification] Error: ${error.message}`);
            throw error;
        }
    }
}

module.exports = new NotificationService();