import log from 'loglevel' import * as util from './util' import BigNumber from 'bignumber.js' import contractMap from 'eth-contract-metadata' const casedContractMap = Object.keys(contractMap).reduce((acc, base) => { return { ...acc, [base.toLowerCase()]: contractMap[base], } }, {}) const DEFAULT_SYMBOL = '' const DEFAULT_DECIMALS = '0' async function getSymbolFromContract (tokenAddress) { const token = util.getContractAtAddress(tokenAddress) try { const result = await token.symbol() return result[0] } catch (error) { log.warn(`symbol() call for token at address ${tokenAddress} resulted in error:`, error) } } async function getDecimalsFromContract (tokenAddress) { const token = util.getContractAtAddress(tokenAddress) try { const result = await token.decimals() const decimalsBN = result[0] return decimalsBN && decimalsBN.toString() } catch (error) { log.warn(`decimals() call for token at address ${tokenAddress} resulted in error:`, error) } } function getContractMetadata (tokenAddress) { return tokenAddress && casedContractMap[tokenAddress.toLowerCase()] } async function getSymbol (tokenAddress) { let symbol = await getSymbolFromContract(tokenAddress) if (!symbol) { const contractMetadataInfo = getContractMetadata(tokenAddress) if (contractMetadataInfo) { symbol = contractMetadataInfo.symbol } } return symbol } async function getDecimals (tokenAddress) { let decimals = await getDecimalsFromContract(tokenAddress) if (!decimals || decimals === '0') { const contractMetadataInfo = getContractMetadata(tokenAddress) if (contractMetadataInfo) { decimals = contractMetadataInfo.decimals } } return decimals } export async function fetchSymbolAndDecimals (tokenAddress) { let symbol, decimals try { symbol = await getSymbol(tokenAddress) decimals = await getDecimals(tokenAddress) } catch (error) { log.warn(`symbol() and decimal() calls for token at address ${tokenAddress} resulted in error:`, error) } return { symbol: symbol || DEFAULT_SYMBOL, decimals: decimals || DEFAULT_DECIMALS, } } export async function getSymbolAndDecimals (tokenAddress, existingTokens = []) { const existingToken = existingTokens.find(({ address }) => tokenAddress === address) if (existingToken) { return { symbol: existingToken.symbol, decimals: existingToken.decimals, } } let symbol, decimals try { symbol = await getSymbol(tokenAddress) decimals = await getDecimals(tokenAddress) } catch (error) { log.warn(`symbol() and decimal() calls for token at address ${tokenAddress} resulted in error:`, error) } return { symbol: symbol || DEFAULT_SYMBOL, decimals: decimals || DEFAULT_DECIMALS, } } export function tokenInfoGetter () { const tokens = {} return async (address) => { if (tokens[address]) { return tokens[address] } tokens[address] = await getSymbolAndDecimals(address) return tokens[address] } } export function calcTokenAmount (value, decimals) { const multiplier = Math.pow(10, Number(decimals || 0)) return new BigNumber(String(value)).div(multiplier) } export function calcTokenValue (value, decimals) { const multiplier = Math.pow(10, Number(decimals || 0)) return new BigNumber(String(value)).times(multiplier) } export function getTokenValue (tokenParams = []) { const valueData = tokenParams.find(param => param.name === '_value') return valueData && valueData.value } export function getTokenToAddress (tokenParams = []) { const toAddressData = tokenParams.find(param => param.name === '_to') return toAddressData ? toAddressData.value : tokenParams[0].value }