const express = require('express');
const cors = require('cors')
const bodyParser = require('body-parser')
const CashPay = require('@developers.cash/cash-pay-server-js')
const catalog = require('./public/catalog.json')

async function main() {
  const app = express()

  app.use(express.static('public'))
  app.use(bodyParser.json())
  app.use(cors())

  // This will pull the Public Key from the pay.infra.cash server
  let webhook = new CashPay.Webhook()
  await webhook.addTrusted('https://pay.infra.cash')

  // Let's store a list of Orders as InvoiceID:Status pairs.
  let orders = {}

  app.post('/request-invoice', async (req, res) => {
    // Don't trust the browser to send correct prices and item details. Use the item id and read from the catalog directly.
    let items = req.body.cart.map(cartItem =>
      catalog.find((catalogItem) => cartItem.id === catalogItem.id)
    )

    // Calculate the total amount due
    let total = items.reduce((total, item) => total += item.price, 0)

    // Set the parameters of the invoice
    let invoice = new CashPay.Invoice()
    invoice.addAddress('bitcoincash:qplf0j8krjrsv95v0t3zj9dc4rcutw5khyy8dc80fu', `${total}USD`)
      .setWebhook(['broadcasting', 'broadcasted', 'confirmed'], 'https://store.example.developers.cash/webhook')
      .setPrivateData({
        customer: req.body.customer, // Customer details
        items: items
      })

    // Actually create the invoice
    await invoice.create()

    // Create an entry for this InvoiceID in our list of orders
    orders[invoice.invoice.id] = 'pending'

    // Return the invoice (this method will omit sensitive data (unless 'true' is passed as a param)
    return res.send(invoice.getPayload())
  })

  app.post('/webhook', async (req, res) => {
    try {
      // An exception will be thrown if signature does not match
      await webhook.verifySignature(req.body, req.headers)

      // The type of event (e.g. broadcasting, broadcasted or confirmed)
      let eventType = req.body.event
      let invoice = req.body.invoice

      // Make sure this invoice was created by us
      if (typeof orders[invoice.id] === 'undefined') {
        throw new Error(`${eventType}: Invoice ${invoice.id} does not exist in our orders.`)
      }

      // Mark the invoice as broadcasting/broadcasted/confirmed
      orders[invoice.id] = eventType

      // Get the data associated with the invoice
      let data = JSON.parse(invoice.options.privateData)

      // Output event type and list of items to console
      console.log(`${data.customer.email} ${eventType}:`)
      console.log(`  ${data.customer.comments}`)
      data.items.forEach(item => { console.log(`  ${item.id}: ${item.title}`) })

      // You must send a 200 response, otherwise CashPay will throw an error
      res.status(200).send('Success')
    } catch(err) {
      console.log(err)
      res.status(500).send(err.message)
    }
  })

  let server = app.listen(8080, function () {
    console.log('Server is now running on Port 8080')
  })
}

main();