xrpio/src/xrpIO/xrpl-binding.ts

import { defaultOptions, Memo, Options } from '../util/types'
import { Client, Payment, TxResponse, Wallet } from 'xrpl'

import * as zlib from 'zlib'
import * as util from 'util'
import { NON_ZERO_TX_HASH } from '../util/protocol.constants'
import { ERR_BAD_TX_HASH } from '../util/errors'

const compressB64 = async (data: string) => (await util.promisify(zlib.deflate)(Buffer.from(data, 'utf-8'))).toString('base64')
const decompressB64 = async (data: string) => (await util.promisify(zlib.inflate)(Buffer.from(data, 'base64'))).toString('utf-8')
const hexDecode = (str: string) => Buffer.from(str, 'hex').toString('utf8')
const hexEncode = (str: string) => Buffer.from(str, 'utf8').toString('hex').toUpperCase()
const chunkString = (str: string, length: number) => str.match(new RegExp('.{1,' + length + '}', 'gs'));
const genRandHex = size => [...Array(size)].map(() => Math.floor(Math.random() * 16).toString(16)).join('');
const PAYLOAD_SIZE = 925
const XRP_PER_DROP = 0.000001
const DROP_PER_XRP = 1000000


export class xrpIO {
  private api: Client

  constructor(
    private server: string,
    private options: Options = defaultOptions
  ) {

    this.options.debug = options.debug ? Boolean(options.debug) : defaultOptions.debug
    this.options.connectionTimeout = options.connectionTimeout ? Number(options.connectionTimeout) : defaultOptions.connectionTimeout
    this.options.readMaxRetry = options.readMaxRetry ? Number(options.readMaxRetry) : defaultOptions.readMaxRetry
    this.options.readRetryTimeout = options.readRetryTimeout ? Number(options.readRetryTimeout) : defaultOptions.readRetryTimeout

    this.api = new Client(server, {
      connectionTimeout: this.options.connectionTimeout
    })
  }

  public async connect(): Promise<void> {
    if (!this.api.isConnected())
      await this.api.connect()
  }

  public async disconnect(): Promise<void> {
    try {
      await this.api.disconnect()
    } catch (e) {
      console.log("DISCONNECT ERROR", e)
    }
  }

  private async cloneApi(): Promise<Client> {
    let _api = new Client(this.server, {
      connectionTimeout: this.options.connectionTimeout
    })

    while (!_api.isConnected()) {
      try {
        await _api.connect()
        return _api
      } catch (e) {
        this.dbg('CLONEAPI ERR', 'Connection failed', String(e['message']))
        await _api.disconnect()
        _api = new Client(this.server, {
          connectionTimeout: this.options.connectionTimeout
        })
      }
    }
  }

  private async sendPayment(data: Memo, to: string, secret: string, sequence?: number, amount: string = "1"): Promise<TxResponse> {
    const wallet = Wallet.fromSecret(secret)
    this.dbg("Sending payment", wallet.address, '->', to)

    const _api = await this.cloneApi()
    try {
      const payment: Payment = await _api.autofill({
        TransactionType: 'Payment',
        Account: wallet.address,
        Destination: to,
        Sequence: sequence,
        Amount: amount,
        Memos: [{
          Memo: {
            MemoData: hexEncode(data.data || ""),
            MemoFormat: hexEncode(data.format || ""),
            MemoType: hexEncode(data.type || "")
          }
        }]
      })


      const response = await _api.submitAndWait(payment, { wallet })
      await _api.disconnect()
      this.dbg("Tx finalized", response.result.hash, response.result.Sequence)
      return response
    } catch (error: any) {
      this.dbg("SENDPAYMENT ERROR", error)
      await _api.disconnect()
      throw error
    }
  }

  public async writeRaw(data: Memo, to: string, secret: string, sequence?: number, amount: string = "1"): Promise<string> {
    this.dbg("Writing data", data)
    const tx = await this.sendPayment(data, to, secret, sequence, amount)
    return tx.result.hash
  }

  private async getTransaction(hash: string, retry = 0): Promise<TxResponse> {
    this.dbg("Getting Tx", hash)
    try {
      return await this.api.request({
        command: 'tx',
        transaction: hash,
      })
    } catch (e) {
      this.dbg(e)
      if (this.options.readMaxRetry != -1) {
        if (retry >= this.options.readMaxRetry)
          console.error("Retry limit exceeded for", hash, ". This is an irrecoverable error")
        throw e
      }
      await new Promise(res => setTimeout(res, this.options.readRetryTimeout))
      return await this.getTransaction(hash, retry + 1)
    }
  }

  public async readRaw(hash: string): Promise<Memo> {

    if (!NON_ZERO_TX_HASH.test(hash)) {
      throw ERR_BAD_TX_HASH(hash)
    }

    const tx = await this.getTransaction(hash)
    const memo = tx.result.Memos[0].Memo
    const memoParsed = {
      data: hexDecode(memo.MemoData),
      format: hexDecode(memo.MemoFormat),
      type: hexDecode(memo.MemoType)
    }
    this.dbg(hash, "data", memoParsed)
    return memoParsed
  }

  public async treeWrite(data: string, to: string, secret: string, format: 'L' | 'N' = 'L'): Promise<string> {
    const wallet = Wallet.fromSecret(secret)
    data = await compressB64(data)
    const chunks = chunkString(data, PAYLOAD_SIZE)
    const latestSequence = await this.getAccountSequence(wallet.address)
    const hashes = await Promise.all(Object.entries(chunks).map(([i, chunk]) => this.writeRaw({ data: chunk, format: format }, to, secret, latestSequence + Number(i))))

    if (hashes.length === 1) {
      return hashes[0]
    }

    return await this.treeWrite(JSON.stringify(hashes), to, secret, 'N')
  }

  public async treeRead(hashes: string[]): Promise<string> {
    const bad_hash = hashes.find(hash => !NON_ZERO_TX_HASH.test(hash))
    if (bad_hash)
      throw ERR_BAD_TX_HASH(bad_hash)

    const memos = await Promise.all(hashes.map(hash => this.readRaw(hash)))
    const payload: string = await decompressB64(memos.map(memo => memo.data).join(''))

    if (memos.some(memo => memo.format === 'N')) {
      return await this.treeRead(JSON.parse(payload))
    }

    return payload
  }

  public async getAccountSequence(address: string): Promise<number> {
    this.dbg("Getting acc info for", address)
    const accountInfo = await this.api.request({
      command: 'account_info',
      account: address,
      strict: true,
    })
    this.dbg("Got account_info", accountInfo)
    return Number(accountInfo.result.account_data.Sequence)
  }

  public async estimateFee(data: string, denomination: 'XRP' | 'DROPS' = 'DROPS', cost = 0): Promise<number> {
    data = await compressB64(data)
    const chunks = chunkString(data, PAYLOAD_SIZE)

    if (chunks.length === 1) {
      return (denomination === "DROPS" ? (cost + 1) : this.dropsToXrp(cost + 1))
    }

    return this.estimateFee(JSON.stringify(chunks.map(_ => genRandHex(64))), denomination, cost + chunks.length)
  }

  public xrpToDrops(xrp: number): number {
    return xrp * DROP_PER_XRP
  }

  public dropsToXrp(drops: number): number {
    return drops * XRP_PER_DROP
  }

  private dbg(...args: any[]) {
    if (this.options.debug) {
      console.log.apply(console, args)
    }
  }
}