Function AmountInput

components/AmountInput.tsx:103–481

};

export const AmountInput: React.FC<AmountInputProps> = props => {
  const textInputRef = useRef<TextInput>(null);
  const { colors } = useTheme();
  const amount = props.amount || '0'; // internally amount is aways a string with a correct number
  const {
    onChangeText,
    unit,
    onAmountUnitChange,
    disabled = false,
    isLoading = false,
    maxSendableAmount,
    isMaxAmountEstimate,
    style: styleOverride,
    ...otherProps
  } = props;
  const [isRateBeingUpdatedLocal, setIsRateBeingUpdatedLocal] = useState(false);
  const [outdatedRefreshRate, setOutdatedRefreshRate] = useState<CurrencyRate | undefined>();

  const maxLength = useMemo(() => {
    switch (unit) {
      case BitcoinUnit.BTC:
        return 11;
      case BitcoinUnit.SATS:
        return 15;
      default:
        return 15;
    }
  }, [unit]);

  const displayAmount = useMemo(() => {
    if (amount === BitcoinUnit.MAX) {
      return loc.units.MAX;
    }

    return parseFloat(amount) >= 0 ? String(amount) : undefined;
  }, [amount]);

  const inputFontSize = useMemo(() => (amount.length > 10 ? 20 : 36), [amount.length]);

  const measureAmountText = displayAmount && displayAmount.length > 0 ? displayAmount : '0';

  const inputTextAlign = useMemo((): 'left' | 'right' | 'center' => {
    if (amount === BitcoinUnit.MAX) return 'center';
    return unit === BitcoinUnit.LOCAL_CURRENCY ? 'left' : 'right';
  }, [amount, unit]);

  const secondaryDisplayCurrency = useMemo(() => {
    if (amount === BitcoinUnit.MAX) {
      return '';
    }
    switch (unit) {
      case BitcoinUnit.BTC: {
        const sat = new BigNumber(amount).multipliedBy(100000000).toNumber();
        return formatBalanceWithoutSuffix(sat, BitcoinUnit.LOCAL_CURRENCY, false);
      }
      case BitcoinUnit.SATS:
        return formatBalanceWithoutSuffix(Number(amount), BitcoinUnit.LOCAL_CURRENCY, false);
      case BitcoinUnit.LOCAL_CURRENCY: {