ipMasking with redux-form Field component normalize

ipNormalize.js

const ipNormalize = (value, prev, values, prevValues) => {
  let length = value.length
  let index = value.lastIndexOf('.') + 1
  let noOfDots = value.split('.').length -1
  let updatedVal = ''
  if (length !== index && noOfDots < 3 && prev.length < length && (length - index) % 3 == 0) {
    updatedVal = value + '.'
  }
  else if (noOfDots > 3 || length - index > 3){
    let newString = value.substring(0, length - 1)
    updatedVal = newString
  }
  else {
    updatedVal = value
  }
  
  return updatedVal
}