useETHPrice.ts

const uniswapV3PoolABI = [
  {
    inputs: [],
    name: 'slot0',
    outputs: [
      { internalType: 'uint160', name: 'sqrtPriceX96', type: 'uint160' },
      { internalType: 'int24', name: 'tick', type: 'int24' },
      { internalType: 'uint16', name: 'observationIndex', type: 'uint16' },
      {
        internalType: 'uint16',
        name: 'observationCardinality',
        type: 'uint16',
      },
      {
        internalType: 'uint16',
        name: 'observationCardinalityNext',
        type: 'uint16',
      },
      { internalType: 'uint8', name: 'feeProtocol', type: 'uint8' },
      { internalType: 'bool', name: 'unlocked', type: 'bool' },
    ],
    stateMutability: 'view',
    type: 'function',
  },
] as const

const uniswapV3USDCPoolAddress = '0x88e6A0c2dDD26FEEb64F039a2c41296FcB3f5640'

export const useETHPrice = (decimalPlaces = 2) => {
  const { data } = useContractRead({
    abi: uniswapV3PoolABI,
    address: uniswapV3USDCPoolAddress,
    chainId: 1,
    functionName: 'slot0',
  })

  return useMemo(() => {
    if (data === undefined) return undefined

    const usdcDecimals = 6n
    const ethDecimals = 18n

    const num = BigInt(2) ** BigInt(192)
    const num2 =
      num * 10n ** (ethDecimals - usdcDecimals + BigInt(decimalPlaces))

    const squared = data[0] * data[0]

    const resBig = num2 / squared
    const result = Number(resBig) / 10 ** Number(decimalPlaces)

    return result
  }, [data, decimalPlaces])
}