metamask-extension/ui/app/pages/confirm-approve/confirm-approve.js

import React, { useEffect, useRef, useState } from 'react'
import { useDispatch, useSelector } from 'react-redux'
import { useParams } from 'react-router-dom'
import ConfirmTransactionBase from '../confirm-transaction-base'
import ConfirmApproveContent from './confirm-approve-content'
import { getCustomTxParamsData } from './confirm-approve.util'
import { showModal } from '../../store/actions'
import {
  getTokenData,
} from '../../helpers/utils/transactions.util'
import {
  calcTokenAmount,
  getTokenToAddress,
  getTokenValue,
} from '../../helpers/utils/token-util'
import { useTokenTracker } from '../../hooks/useTokenTracker'
import { getTokens } from '../../ducks/metamask/metamask'
import {
  transactionFeeSelector,
  txDataSelector,
} from '../../selectors/confirm-transaction'
import { getCurrentCurrency, getDomainMetadata } from '../../selectors/selectors'
import { currentNetworkTxListSelector } from '../../selectors/transactions'

export default function ConfirmApprove () {
  const dispatch = useDispatch()
  const { id: paramsTransactionId } = useParams()
  const {
    id: transactionId,
    txParams: {
      to: tokenAddress,
      data,
    } = {},
  } = useSelector(txDataSelector)

  const currentCurrency = useSelector(getCurrentCurrency)
  const currentNetworkTxList = useSelector(currentNetworkTxListSelector)
  const domainMetadata = useSelector(getDomainMetadata)
  const tokens = useSelector(getTokens)

  const transaction = (
    currentNetworkTxList.find(({ id }) => id === (Number(paramsTransactionId) || transactionId)) || {}
  )
  const {
    ethTransactionTotal,
    fiatTransactionTotal,
  } = useSelector((state) => transactionFeeSelector(state, transaction))

  const currentToken = (tokens && tokens.find(({ address }) => tokenAddress === address)) || { address: tokenAddress }

  const { tokensWithBalances } = useTokenTracker([currentToken])
  const tokenTrackerBalance = tokensWithBalances[0]?.balance || ''

  const tokenSymbol = currentToken?.symbol
  const decimals = Number(currentToken?.decimals)
  const tokenData = getTokenData(data)
  const tokenValue = tokenData && getTokenValue(tokenData.params)
  const toAddress = tokenData && getTokenToAddress(tokenData.params)
  const tokenAmount = tokenData && calcTokenAmount(tokenValue, decimals).toString(10)

  const [customPermissionAmount, setCustomPermissionAmount] = useState('')

  const previousTokenAmount = useRef(tokenAmount)

  useEffect(
    () => {
      if (customPermissionAmount && previousTokenAmount.current !== tokenAmount) {
        setCustomPermissionAmount(tokenAmount)
      }
      previousTokenAmount.current = tokenAmount
    },
    [customPermissionAmount, tokenAmount]
  )

  const { origin } = transaction
  const formattedOrigin = origin
    ? origin[0].toUpperCase() + origin.slice(1)
    : ''
  const txData = transaction

  const { icon: siteImage = '' } = domainMetadata[origin] || {}

  const tokensText = `${Number(tokenAmount)} ${tokenSymbol}`
  const tokenBalance = tokenTrackerBalance
    ? calcTokenAmount(tokenTrackerBalance, decimals).toString(10)
    : ''
  const customData = customPermissionAmount
    ? getCustomTxParamsData(data, { customPermissionAmount, decimals })
    : null

  return (
    <ConfirmTransactionBase
      toAddress={toAddress}
      identiconAddress={tokenAddress}
      showAccountInHeader
      title={tokensText}
      contentComponent={(
        <ConfirmApproveContent
          decimals={decimals}
          siteImage={siteImage}
          setCustomAmount={setCustomPermissionAmount}
          customTokenAmount={String(customPermissionAmount)}
          tokenAmount={tokenAmount}
          origin={formattedOrigin}
          tokenSymbol={tokenSymbol}
          tokenBalance={tokenBalance}
          showCustomizeGasModal={() => dispatch(showModal({ name: 'CUSTOMIZE_GAS', txData }))}
          showEditApprovalPermissionModal={
            ({
              customTokenAmount,
              decimals,
              origin,
              setCustomAmount,
              tokenAmount,
              tokenBalance,
              tokenSymbol,
            }) => dispatch(
              showModal({
                name: 'EDIT_APPROVAL_PERMISSION',
                customTokenAmount,
                decimals,
                origin,
                setCustomAmount,
                tokenAmount,
                tokenBalance,
                tokenSymbol,
              })
            )
          }
          data={customData || data}
          toAddress={toAddress}
          currentCurrency={currentCurrency}
          ethTransactionTotal={ethTransactionTotal}
          fiatTransactionTotal={fiatTransactionTotal}
        />
      )}
      hideSenderToRecipient
      customTxParamsData={customData}
    />
  )
}