import log from 'loglevel' import BigNumber from 'bignumber.js' import abi from 'human-standard-token-abi' import { isValidAddress } from 'ethereumjs-util' import { ETH_SWAPS_TOKEN_OBJECT } from '../../helpers/constants/swaps' import { calcTokenValue, calcTokenAmount } from '../../helpers/utils/token-util' import { constructTxParams, toPrecisionWithoutTrailingZeros } from '../../helpers/utils/util' import { decimalToHex, getValueFromWeiHex } from '../../helpers/utils/conversions.util' import { subtractCurrencies } from '../../helpers/utils/conversion-util' import { formatCurrency } from '../../helpers/utils/confirm-tx.util' import fetchWithCache from '../../helpers/utils/fetch-with-cache' import { calcGasTotal } from '../send/send.utils' const TOKEN_TRANSFER_LOG_TOPIC_HASH = '0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef' const CACHE_REFRESH_ONE_HOUR = 3600000 const getBaseApi = function (type) { switch (type) { case 'trade': return `https://api.metaswap.codefi.network/trades?` case 'tokens': return `https://api.metaswap.codefi.network/tokens` case 'topAssets': return `https://api.metaswap.codefi.network/topAssets` case 'featureFlag': return `https://api.metaswap.codefi.network/featureFlag` case 'aggregatorMetadata': return `https://api.metaswap.codefi.network/aggregatorMetadata` default: throw new Error('getBaseApi requires an api call type') } } const validHex = (string) => Boolean(string?.match(/^0x[a-f0-9]+$/u)) const truthyString = (string) => Boolean(string?.length) const truthyDigitString = (string) => truthyString(string) && Boolean(string.match(/^\d+$/u)) const QUOTE_VALIDATORS = [ { property: 'trade', type: 'object', validator: (trade) => trade && validHex(trade.data) && isValidAddress(trade.to) && isValidAddress(trade.from) && truthyString(trade.value), }, { property: 'approvalNeeded', type: 'object', validator: (approvalTx) => ( approvalTx === null || ( approvalTx && validHex(approvalTx.data) && isValidAddress(approvalTx.to) && isValidAddress(approvalTx.from) ) ), }, { property: 'sourceAmount', type: 'string', validator: truthyDigitString, }, { property: 'destinationAmount', type: 'string', validator: truthyDigitString, }, { property: 'sourceToken', type: 'string', validator: isValidAddress, }, { property: 'destinationToken', type: 'string', validator: isValidAddress, }, { property: 'aggregator', type: 'string', validator: truthyString, }, { property: 'aggType', type: 'string', validator: truthyString, }, { property: 'error', type: 'object', validator: (error) => error === null || typeof error === 'object', }, { property: 'averageGas', type: 'number', }, { property: 'maxGas', type: 'number', }, ] const TOKEN_VALIDATORS = [ { property: 'address', type: 'string', validator: isValidAddress, }, { property: 'symbol', type: 'string', validator: (string) => truthyString(string) && string.length <= 12, }, { property: 'decimals', type: 'string|number', validator: (string) => Number(string) >= 0 && Number(string) <= 36, }, ] const TOP_ASSET_VALIDATORS = TOKEN_VALIDATORS.slice(0, 2) const AGGREGATOR_METADATA_VALIDATORS = [ { property: 'color', type: 'string', validator: (string) => Boolean(string.match(/^#[A-Fa-f0-9]+$/u)), }, { property: 'title', type: 'string', validator: truthyString, }, { property: 'icon', type: 'string', validator: (string) => Boolean(string.match(/^data:image/u)), }, ] function validateData (validators, object, urlUsed) { return validators.every(({ property, type, validator }) => { const types = type.split('|') const valid = types.some((_type) => typeof object[property] === _type) && (!validator || validator(object[property])) if (!valid) { log.error(`response to GET ${urlUsed} invalid for property ${property}; value was:`, object[property], '| type was: ', typeof object[property]) } return valid }) } export async function fetchTradesInfo ({ slippage, sourceToken, sourceDecimals, destinationToken, value, fromAddress, exchangeList, }) { const urlParams = { destinationToken, sourceToken, sourceAmount: calcTokenValue(value, sourceDecimals).toString(10), slippage, timeout: 10000, walletAddress: fromAddress, } if (exchangeList) { urlParams.exchangeList = exchangeList } const queryString = new URLSearchParams(urlParams).toString() const tradeURL = `${getBaseApi('trade')}${queryString}` const tradesResponse = await fetchWithCache(tradeURL, { method: 'GET' }, { cacheRefreshTime: 0, timeout: 15000 }) const newQuotes = tradesResponse.reduce((aggIdTradeMap, quote) => { if (quote.trade && !quote.error && validateData(QUOTE_VALIDATORS, quote, tradeURL)) { const constructedTrade = constructTxParams({ to: quote.trade.to, from: quote.trade.from, data: quote.trade.data, amount: decimalToHex(quote.trade.value), gas: decimalToHex(quote.maxGas), }) let { approvalNeeded } = quote if (approvalNeeded) { approvalNeeded = constructTxParams({ ...approvalNeeded, }) } return { ...aggIdTradeMap, [quote.aggregator]: { ...quote, slippage, trade: constructedTrade, approvalNeeded, }, } } return aggIdTradeMap }, {}) return newQuotes } export async function fetchTokens () { const tokenUrl = getBaseApi('tokens') const tokens = await fetchWithCache(tokenUrl, { method: 'GET' }, { cacheRefreshTime: CACHE_REFRESH_ONE_HOUR }) const filteredTokens = tokens.filter((token) => { return validateData(TOKEN_VALIDATORS, token, tokenUrl) && (token.address !== ETH_SWAPS_TOKEN_OBJECT.address) }) filteredTokens.push(ETH_SWAPS_TOKEN_OBJECT) return filteredTokens } export async function fetchAggregatorMetadata () { const aggregatorMetadataUrl = getBaseApi('aggregatorMetadata') const aggregators = await fetchWithCache(aggregatorMetadataUrl, { method: 'GET' }, { cacheRefreshTime: CACHE_REFRESH_ONE_HOUR }) const filteredAggregators = {} for (const aggKey in aggregators) { if (validateData(AGGREGATOR_METADATA_VALIDATORS, aggregators[aggKey], aggregatorMetadataUrl)) { filteredAggregators[aggKey] = aggregators[aggKey] } } return filteredAggregators } export async function fetchTopAssets () { const topAssetsUrl = getBaseApi('topAssets') const response = await fetchWithCache(topAssetsUrl, { method: 'GET' }, { cacheRefreshTime: CACHE_REFRESH_ONE_HOUR }) const topAssetsMap = response.reduce((_topAssetsMap, asset, index) => { if (validateData(TOP_ASSET_VALIDATORS, asset, topAssetsUrl)) { return { ..._topAssetsMap, [asset.address]: { index: String(index) } } } return _topAssetsMap }, {}) return topAssetsMap } export async function fetchSwapsFeatureLiveness () { const status = await fetchWithCache(getBaseApi('featureFlag'), { method: 'GET' }, { cacheRefreshTime: 600000 }) return status?.active } export async function fetchTokenPrice (address) { const query = `contract_addresses=${address}&vs_currencies=eth` const prices = await fetchWithCache(`https://api.coingecko.com/api/v3/simple/token_price/ethereum?${query}`, { method: 'GET' }, { cacheRefreshTime: 60000 }) return prices && prices[address]?.eth } export async function fetchTokenBalance (address, userAddress) { const tokenContract = global.eth.contract(abi).at(address) const tokenBalancePromise = tokenContract ? tokenContract.balanceOf(userAddress) : Promise.resolve() const usersToken = await tokenBalancePromise return usersToken } export function getRenderableGasFeesForQuote (tradeGas, approveGas, gasPrice, currentCurrency, conversionRate) { const totalGasLimitForCalculation = (new BigNumber(tradeGas || '0x0', 16)).plus(approveGas || '0x0', 16).toString(16) const gasTotalInWeiHex = calcGasTotal(totalGasLimitForCalculation, gasPrice) const ethFee = getValueFromWeiHex({ value: gasTotalInWeiHex, toDenomination: 'ETH', numberOfDecimals: 5, }) const rawNetworkFees = getValueFromWeiHex({ value: gasTotalInWeiHex, toCurrency: currentCurrency, conversionRate, numberOfDecimals: 2, }) const formattedNetworkFee = formatCurrency(rawNetworkFees, currentCurrency) return { rawNetworkFees, rawEthFee: ethFee, feeInFiat: formattedNetworkFee, feeInEth: `${ethFee} ETH`, } } export function quotesToRenderableData (quotes, gasPrice, conversionRate, currentCurrency, approveGas, tokenConversionRates) { return Object.values(quotes).map((quote) => { const { destinationAmount = 0, sourceAmount = 0, sourceTokenInfo, destinationTokenInfo, slippage, aggType, aggregator, gasEstimateWithRefund, averageGas, fee, } = quote const sourceValue = calcTokenAmount(sourceAmount, sourceTokenInfo.decimals || 18).toString(10) const destinationValue = calcTokenAmount(destinationAmount, destinationTokenInfo.decimals || 18).toPrecision(8) const { feeInFiat, rawNetworkFees, rawEthFee, feeInEth, } = getRenderableGasFeesForQuote( ( gasEstimateWithRefund || decimalToHex(averageGas || 800000) ), approveGas, gasPrice, currentCurrency, conversionRate, ) const slippageMultiplier = (new BigNumber(100 - slippage)).div(100) const minimumAmountReceived = (new BigNumber(destinationValue)).times(slippageMultiplier).toFixed(6) const tokenConversionRate = tokenConversionRates[destinationTokenInfo.address] const ethValueOfTrade = destinationTokenInfo.symbol === 'ETH' ? calcTokenAmount(destinationAmount, destinationTokenInfo.decimals || 18).minus(rawEthFee, 10) : (new BigNumber(tokenConversionRate || 0, 10)) .times(calcTokenAmount(destinationAmount, destinationTokenInfo.decimals || 18), 10) .minus(rawEthFee, 10) let liquiditySourceKey let renderedSlippage = slippage if (aggType === 'AGG') { liquiditySourceKey = 'swapAggregator' } else if (aggType === 'RFQ') { liquiditySourceKey = 'swapRequestForQuotation' renderedSlippage = 0 } else if (aggType === 'DEX') { liquiditySourceKey = 'swapDecentralizedExchange' } else { liquiditySourceKey = 'swapUnknown' } return { aggId: aggregator, amountReceiving: `${destinationValue} ${destinationTokenInfo.symbol}`, destinationTokenDecimals: destinationTokenInfo.decimals, destinationTokenSymbol: destinationTokenInfo.symbol, destinationTokenValue: formatSwapsValueForDisplay(destinationValue), destinationIconUrl: destinationTokenInfo.iconUrl, isBestQuote: quote.isBestQuote, liquiditySourceKey, feeInEth, detailedNetworkFees: `${feeInEth} (${feeInFiat})`, networkFees: feeInFiat, quoteSource: aggType, rawNetworkFees, slippage: renderedSlippage, sourceTokenDecimals: sourceTokenInfo.decimals, sourceTokenSymbol: sourceTokenInfo.symbol, sourceTokenValue: sourceValue, sourceTokenIconUrl: sourceTokenInfo.iconUrl, ethValueOfTrade, minimumAmountReceived, metaMaskFee: fee, } }) } export function getSwapsTokensReceivedFromTxMeta (tokenSymbol, txMeta, tokenAddress, accountAddress, tokenDecimals, approvalTxMeta) { const txReceipt = txMeta?.txReceipt if (tokenSymbol === 'ETH') { if (!txReceipt || !txMeta || !txMeta.postTxBalance || !txMeta.preTxBalance) { return null } let approvalTxGasCost = '0x0' if (approvalTxMeta && approvalTxMeta.txReceipt) { approvalTxGasCost = calcGasTotal(approvalTxMeta.txReceipt.gasUsed, approvalTxMeta.txParams.gasPrice) } const gasCost = calcGasTotal(txReceipt.gasUsed, txMeta.txParams.gasPrice) const totalGasCost = (new BigNumber(gasCost, 16)).plus(approvalTxGasCost, 16).toString(16) const preTxBalanceLessGasCost = subtractCurrencies(txMeta.preTxBalance, totalGasCost, { aBase: 16, bBase: 16, toNumericBase: 'hex', }) const ethReceived = subtractCurrencies(txMeta.postTxBalance, preTxBalanceLessGasCost, { aBase: 16, bBase: 16, fromDenomination: 'WEI', toDenomination: 'ETH', toNumericBase: 'dec', numberOfDecimals: 6, }) return ethReceived } const txReceiptLogs = txReceipt?.logs if (txReceiptLogs && txReceipt?.status !== '0x0') { const tokenTransferLog = txReceiptLogs.find((txReceiptLog) => { const isTokenTransfer = txReceiptLog.topics && txReceiptLog.topics[0] === TOKEN_TRANSFER_LOG_TOPIC_HASH const isTransferFromGivenToken = txReceiptLog.address === tokenAddress const isTransferFromGivenAddress = txReceiptLog.topics && txReceiptLog.topics[2] && txReceiptLog.topics[2].match(accountAddress.slice(2)) return isTokenTransfer && isTransferFromGivenToken && isTransferFromGivenAddress }) return tokenTransferLog ? toPrecisionWithoutTrailingZeros( calcTokenAmount(tokenTransferLog.data, tokenDecimals).toString(10), 6, ) : '' } return null } export function formatSwapsValueForDisplay (destinationAmount) { let amountToDisplay = toPrecisionWithoutTrailingZeros(destinationAmount, 12) if (amountToDisplay.match(/e[+-]/u)) { amountToDisplay = (new BigNumber(amountToDisplay)).toFixed() } return amountToDisplay }