pago/main.js

const dotenv = require('dotenv')
const express = require('express')
const cors = require('cors')
const Wallet = require('monero-wallet-rpc-js')
const {createServer} = require('node:http')
const {Server} = require('socket.io')

;(async () => {

	const deAtomize = (atomic) => Number(atomic) * 0.000000000001

	dotenv.config()
	const WALLET_ACCOUNT_INDEX = Number(process.env.WALLET_ACCOUNT_INDEX)
	const WALLET_AUTOSAVE_SEC = Number(process.env.WALLET_AUTOSAVE_SEC)
	const WALLET_REFRESH_SEC = Number(process.env.WALLET_REFRESH_SEC)

	// Load monero wallet
	const wallet = await new Wallet({
		url: process.env.WALLET_RPC_URI,
		filename: process.env.WALLET_FILENAME,
		password: process.env.WALLET_PASSWORD,
		address: process.env.WALLET_ADDRESS,
		viewkey: process.env.WALLET_VIEWKEY,
		restore_height: process.env.WALLET_RESTORE_HEIGHT,
	})

	// Set auto save
	if (WALLET_AUTOSAVE_SEC > 0)
		setInterval(wallet.store(), WALLET_AUTOSAVE_SEC)

	// Set auto refresh
	try {
		await wallet.rpc('auto_refresh', {
			enable:true, period:WALLET_REFRESH_SEC,
		})
		console.log(`Auto-refreshing wallet every ${process.env.WALLET_REFRESH_SEC} seconds. `)
	} catch (err) {
		console.error(`Failed to set auto_refresh to ${process.env.WALLET_REFRESH_SEC}: ${err}`)
	}
	
	// Confirm sync
	try {
		console.log(`Wallet synced to block ${await wallet.getHeight()}.`)
	} catch (err) {
		console.error(`Failed to get blockchain height: ${err}`)
	}

	// Check accounts, create account if needed
	// TODO: Validate that the admin didn't set WALLET_ACCOUNT_INDEX too high
	const getAccount = async (i) => {
		try {
			accounts = (await wallet.getAccounts()).subaddress_accounts
		} catch (err) {
			console.error(`Failed to get account listing from rpc: ${err}`)
		}
		account = accounts.find(a => a.account_index == i)
		if (account===undefined) {
			console.log(`There is no account #${i}. Creating account...`)
			try {
				const newAccount = await wallet.createAccount()
				console.log(`Created account #${newAccount.account_index}.`)
			} catch (err) {
				console.error(`Failed to create new account: ${err}`)
			}
			return getAccount(i)
		} else {
			console.log(`Using account #${i} (balance: ${deAtomize(account.balance)} XMR).`)
			return account
		}
	}; getAccount(WALLET_ACCOUNT_INDEX)


	// Server
	const app = express()
	app.use(express.json())
	app.use(cors({
	//	origin: 'http://example.com',
	}))
	const server = createServer(app)
	const io = new Server(server)
	server.listen(80)

	// Test websockets
	io.on('connection', (socket) => {
		console.log('a user connected')
		socket.on('disconnect', () => {
			console.log('user disconnected')
		})
	})

	// Healthchecks
	app.get('/wallet/height', async (req, res) => 
		res.send((await wallet.getHeight()).toString())
	)
	app.get('/wallet/balance', async (req, res) => {
		let result; try {
			result = await wallet.getBalance({
				account_index: WALLET_ACCOUNT_INDEX,
			})
		} catch (err) {
			console.error(`Failed to get balance: ${err}`)
			return res.sendStatus(500)
		}
		return res.send(`${deAtomize(result.balance)} XMR`)
	})

	// New payment
	app.post('/payment', async (req, res) => {
		let result; try {
			result = await wallet.createAddress({
				account_index: 1,
				label: req.body.label, 
			})
		} catch (err) {
			console.error(`Failed to create address "${req.body.label}": ${err}`)
			return res.sendStatus(500)
		}
		console.log(`Created new payment at subaddress #${result.address_index}`)
		return res.redirect(`/payment/${result.address}`)
	})

	// Check payment
	app.get('/payment/:addr', async (req, res) => {
		let subaddr_index; try {
			subaddr_index = (await wallet.getAddressIndex(req.params.addr)).index.minor
		} catch (err) {
			console.error(`Failed to get index of subaddress: ${err}`)
			return res.sendStatus(500)
		}
		let transfers; try {
			transfers = Object.values(await wallet.getTransfers({
				all_accounts: true,
				in: true,
				out: false,
				pending: true,
				failed: true,
				pool: true,
				account_index: WALLET_ACCOUNT_INDEX,
				subaddr_indices: [subaddr_index],
			})).flat()
		} catch (err) {
			console.error(`Failed to get transactions for subaddress: ${err}`)
			return res.sendStatus(500)
		}
		return res.json(transfers)
	})

	// Listen for new transactions
	app.get('/new_tx/:txid', async (req, res) => {
		// TODO: Retry, sleep, retry, give up
		console.log(`New transaction: ${req.params.txid}`)
		let result; try {
			result = await wallet.getTransfersByTxid({
				account_index: WALLET_ACCOUNT_INDEX,
				txid: req.params.txid,
			})
			if (result.transfer===undefined) throw new Error('Multiple transfers?')
		} catch (err) {
			console.error(`Failed to query transaction: ${err}`)
			return res.sendStatus(500)
		}
		console.log(`Transfer received at ${result.transfer.subaddr_index.minor} for ${deAtomize(result.transfer.amount)} XMR to ${result.transfer.address}`)
		// TODO: Send websocket
		return res.sendStatus(200)
	})

})()