convert English phrase to integer

english_phrase_to_integer.js

const splitChars = /\b(billion|million|thoudsand|hundred)s?/g

const points = {
  billion: 1000000000,
  million: 1000000,
  thoudsand: 1000,
  hundred: 100
}

const digits = {
  one: 1,
  two: 2,
  three: 3,
  four: 4,
  five: 5,
  six: 6,
  seven: 7,
  eight: 8,
  nine: 9,
  ten: 10,
  eleven: 11,
  twelve: 12,
  thirteen: 13,
  fourteen: 14,
  fifteen: 15,
  sixteen: 16,
  seventeen: 17,
  eighteen: 18,
  nineteen: 19,
  twenty: 20,
  thirty: 30,
  forty: 40,
  fifty: 50,
  sixty: 60,
  seventy: 70,
  eighty: 80,
  ninety: 90
}

function integerFromEnglishPhrase(str) {
  let value = 0

  const localPoints = [], localDigits = []

  str = str.split(splitChars)

  str.forEach((value, index) => {
    value = value.trim()

    if (value in points) {
      localPoints.push(points[value])
      return
    }

    if (value !== '') {
      localDigits.push(value.split(' ').reduce((a, b) => a + digits[b], 0))
    }
  })

  const totalDigits = Math.max(localPoints.length, localDigits.length)
  let result = 0

  for (var i = 0; i < totalDigits; i++) {
    if (localDigits[i]) {
      result = result + localDigits[i] * (localPoints[i] || 1)
    } else if (localPoints[i]) {
      result = result * localPoints[i]
    }
  }

  if (result > Number.MAX_VALUE) {
    return Infinity
  }

  return result
}

test_cases.js

integerFromEnglishPhrase('one thoudsand two hundred thirty four') // 1234
integerFromEnglishPhrase('one thoudsand two hundred') // 1200
integerFromEnglishPhrase('thirty four') // 34
integerFromEnglishPhrase('one thoudsand billions') // 1000000000000