paymentProcess.js

const express = require('express');
const bodyParser = require('body-parser');
const admin = require('firebase-admin');
const { URL } = require('url'); // Node.js built-in URL module
require('dotenv').config();

const serviceAccount = JSON.parse(process.env.FIREBASE_SERVICE_ACCOUNT);

// Initialize Firebase Admin SDK
admin.initializeApp({
  credential: admin.credential.cert(serviceAccount),
});

const db = admin.firestore();

const app = express();
app.use(bodyParser.json()); 

app.get('/api/ipn-listener', async (req, res) => {
  try {
    const listenerUrl = req.query.url;

    if (!listenerUrl) {
      console.error('Missing `url` parameter');
      return res.status(400).send('Missing `url` parameter');
    }

    console.log('Received URL:', listenerUrl);

    const parsedUrl = new URL(listenerUrl);
    const pathSegments = parsedUrl.pathname.split('/'); 

    console.log(pathSegments)
    

    const MerchantId = pathSegments[5]; 
    const StoreId = pathSegments[6]; 
    const TransactionReferenceNumber = pathSegments[7];

    console.log(`MerchantId: ${MerchantId}`);
    console.log(`StoreId: ${StoreId}`);
    console.log(`TransactionReferenceNumber: ${TransactionReferenceNumber}`);

    if (MerchantId !== process.env.MERCHANT_ID || StoreId !== process.env.STORE_ID) {
      console.error('Invalid MerchantId or StoreId');
      return res.status(400).send('Invalid Merchant or Store ID');
    }



    const axios = require('axios');
    const transactionResponse = await axios.get(listenerUrl);

    if (!transactionResponse.data) {
      console.error('Empty response from transaction status URL');
      return res.status(400).send('Failed to retrieve transaction details');
    }

    const transactionData = JSON.parse(transactionResponse.data);
    console.log('Transaction Data:', transactionData);

    const transactionRef = db.collection('Transactions').doc(TransactionReferenceNumber);

    const transactionSnapshot = await transactionRef.get();
    if (!transactionSnapshot.exists) {
      console.error(`Transaction ${TransactionReferenceNumber} not found`);
      return res.status(404).send('Transaction not found');
    }


    await transactionRef.update({
      Status: transactionData.TransactionStatus, 
      UpdatedAt: admin.firestore.FieldValue.serverTimestamp(),
      transactionId: transactionData.TransactionId
    });

    console.log(`Transaction ${TransactionReferenceNumber} updated successfully`);

    res.status(200).send('IPN Processed Successfully');
  } catch (error) {
    console.error('Error processing IPN:', error);
    res.status(500).send('Internal Server Error');
  }
});

// Start the server
const PORT = process.env.PORT || 3000;
app.listen(PORT, () => {
  console.log(`IPN Listener running on port ${PORT}`);
});