metamask-extension/ui/app/helpers/utils/conversions.util.js

import ethUtil from 'ethereumjs-util'
import BigNumber from 'bignumber.js'
import { ETH, GWEI, WEI } from '../constants/common'
import {
  conversionUtil,
  addCurrencies,
  subtractCurrencies,
} from './conversion-util'
import { formatCurrency } from './confirm-tx.util'

export function bnToHex(inputBn) {
  return ethUtil.addHexPrefix(inputBn.toString(16))
}

export function hexToDecimal(hexValue) {
  return conversionUtil(hexValue, {
    fromNumericBase: 'hex',
    toNumericBase: 'dec',
  })
}

export function decimalToHex(decimal) {
  return conversionUtil(decimal, {
    fromNumericBase: 'dec',
    toNumericBase: 'hex',
  })
}

export function getEthConversionFromWeiHex({
  value,
  fromCurrency = ETH,
  conversionRate,
  numberOfDecimals = 6,
}) {
  const denominations = [fromCurrency, GWEI, WEI]

  let nonZeroDenomination

  for (let i = 0; i < denominations.length; i++) {
    const convertedValue = getValueFromWeiHex({
      value,
      conversionRate,
      fromCurrency,
      toCurrency: fromCurrency,
      numberOfDecimals,
      toDenomination: denominations[i],
    })

    if (convertedValue !== '0' || i === denominations.length - 1) {
      nonZeroDenomination = `${convertedValue} ${denominations[i]}`
      break
    }
  }

  return nonZeroDenomination
}

export function getValueFromWeiHex({
  value,
  fromCurrency = ETH,
  toCurrency,
  conversionRate,
  numberOfDecimals,
  toDenomination,
}) {
  return conversionUtil(value, {
    fromNumericBase: 'hex',
    toNumericBase: 'dec',
    fromCurrency,
    toCurrency,
    numberOfDecimals,
    fromDenomination: WEI,
    toDenomination,
    conversionRate,
  })
}

export function getWeiHexFromDecimalValue({
  value,
  fromCurrency,
  conversionRate,
  fromDenomination,
  invertConversionRate,
}) {
  return conversionUtil(value, {
    fromNumericBase: 'dec',
    toNumericBase: 'hex',
    toCurrency: ETH,
    fromCurrency,
    conversionRate,
    invertConversionRate,
    fromDenomination,
    toDenomination: WEI,
  })
}

export function addHexWEIsToDec(aHexWEI, bHexWEI) {
  return addCurrencies(aHexWEI, bHexWEI, {
    aBase: 16,
    bBase: 16,
    fromDenomination: 'WEI',
    numberOfDecimals: 6,
  })
}

export function subtractHexWEIsToDec(aHexWEI, bHexWEI) {
  return subtractCurrencies(aHexWEI, bHexWEI, {
    aBase: 16,
    bBase: 16,
    fromDenomination: 'WEI',
    numberOfDecimals: 6,
  })
}

export function decEthToConvertedCurrency(
  ethTotal,
  convertedCurrency,
  conversionRate,
) {
  return conversionUtil(ethTotal, {
    fromNumericBase: 'dec',
    toNumericBase: 'dec',
    fromCurrency: 'ETH',
    toCurrency: convertedCurrency,
    numberOfDecimals: 2,
    conversionRate,
  })
}

export function decGWEIToHexWEI(decGWEI) {
  return conversionUtil(decGWEI, {
    fromNumericBase: 'dec',
    toNumericBase: 'hex',
    fromDenomination: 'GWEI',
    toDenomination: 'WEI',
  })
}

export function hexWEIToDecGWEI(decGWEI) {
  return conversionUtil(decGWEI, {
    fromNumericBase: 'hex',
    toNumericBase: 'dec',
    fromDenomination: 'WEI',
    toDenomination: 'GWEI',
  })
}

export function decETHToDecWEI(decEth) {
  return conversionUtil(decEth, {
    fromNumericBase: 'dec',
    toNumericBase: 'dec',
    fromDenomination: 'ETH',
    toDenomination: 'WEI',
  })
}

export function hexWEIToDecETH(hexWEI) {
  return conversionUtil(hexWEI, {
    fromNumericBase: 'hex',
    toNumericBase: 'dec',
    fromDenomination: 'WEI',
    toDenomination: 'ETH',
  })
}

export function hexMax(...hexNumbers) {
  let max = hexNumbers[0]
  hexNumbers.slice(1).forEach((hexNumber) => {
    if (new BigNumber(hexNumber, 16).gt(max, 16)) {
      max = hexNumber
    }
  })
  return max
}

export function addHexes(aHexWEI, bHexWEI) {
  return addCurrencies(aHexWEI, bHexWEI, {
    aBase: 16,
    bBase: 16,
    toNumericBase: 'hex',
    numberOfDecimals: 6,
  })
}

export function sumHexWEIsToRenderableFiat(
  hexWEIs,
  convertedCurrency,
  conversionRate,
) {
  const hexWEIsSum = hexWEIs.filter((n) => n).reduce(addHexes)
  const ethTotal = decEthToConvertedCurrency(
    getValueFromWeiHex({
      value: hexWEIsSum,
      toCurrency: 'ETH',
      numberOfDecimals: 4,
    }),
    convertedCurrency,
    conversionRate,
  )
  return formatCurrency(ethTotal, convertedCurrency)
}