Conversor de número por extenso (string) escrito em português para número inteiro em Javascript

brazilian-portuguese-numeral-text-to-number.js

export const convertPortugueseNumeralNomenclatureToNumber = function PortugueseNumeralNomenclatureConverter() {
  const PORTUGUESE_UNITS_NAMES_ENTRIES = [
    ["zero", 0],
    ["um", 1],
    ["dois", 2],
    ["tres", 3],
    ["três", 3],
    ["quatro", 4],
    ["cinco", 5],
    ["seis", 6],
    ["sete", 7],
    ["oito", 8],
    ["nove", 9],
    ["dez", 10],
    ["onze", 11],
    ["doze", 12],
    ["treze", 13],
    ["quatorze", 14],
    ["catorze", 14],
    ["quinze", 15],
    ["dezesseis", 16],
    ["dezessete", 17],
    ["dezoito", 18],
    ["dezenove", 19]
  ]

  const PORTUGUESE_DOZENS_NAMES_ENTRIES = [
    ["dez", 10],
    ["vinte", 20],
    ["trinta", 30],
    ["quarenta", 40],
    ["cinquenta", 50],
    ["sessenta", 60],
    ["setenta", 70],
    ["oitenta", 80],
    ["noventa", 90],
    ["cem", 100]
  ]

  const PORTUGUESE_HUNDREDS_NAMES_ENTRIES = [
    ["cento", 100],
    ["duzentos", 200],
    ["trezentos", 300],
    ["quatrocentos", 400],
    ["quinhentos", 500],
    ["seiscentos", 600],
    ["setecentos", 700],
    ["oitocentos", 800],
    ["novecentos", 900],
  ]

  const PORTUGUESE_GROUPS_NAMES_ENTRIES = [
    ["mil", 1e3],

    ["milhao", 1e6],
    ["milhão", 1e6],
    ["milhoes", 1e6],
    ["milhões", 1e6],

    ["bilhao", 1e9],
    ["bilhão", 1e9],
    ["bilhoes", 1e9],
    ["bilhões", 1e9],

    ["trilhao", 1e12],
    ["trilhão", 1e12],
    ["trilhoes", 1e12],
    ["trilhões", 1e12],
    // ...
  ]

  const PORTUGUESE_DEFAULT_AGGREGATOR_WORD = "e"
  const PORTUGUESE_NUMERAL_SEPARATOR_REGEX = new RegExp(`\\s*\\b${PORTUGUESE_DEFAULT_AGGREGATOR_WORD}?\\b\\s*`, "gi")

  /** @typedef {[string, number]} nomenclatureNumType  */

  const PortugueseUnitsNamesMap = new Map(/** @type {nomenclatureNumType[]} */(PORTUGUESE_UNITS_NAMES_ENTRIES))
  const PortugueseDozensNamesMap = new Map(/** @type {nomenclatureNumType[]} */(PORTUGUESE_DOZENS_NAMES_ENTRIES))
  const PortugueseHundredsNamesMap = new Map(/** @type {nomenclatureNumType[]} */(PORTUGUESE_HUNDREDS_NAMES_ENTRIES))
  const PortugueseGroupsNamesMap = new Map(/** @type {nomenclatureNumType[]} */(PORTUGUESE_GROUPS_NAMES_ENTRIES))

  /** @param {string} name */
  function toNumber(name) {
    if (PortugueseGroupsNamesMap.has(name)) return PortugueseGroupsNamesMap.get(name)
    else if (PortugueseUnitsNamesMap.has(name)) return PortugueseUnitsNamesMap.get(name)
    else if (PortugueseDozensNamesMap.has(name)) return PortugueseDozensNamesMap.get(name)
    else if (PortugueseHundredsNamesMap.has(name)) return PortugueseHundredsNamesMap.get(name)
    // else throw new Error(`The name "${name}" is not a valid argument`)
    else return Number.NaN
  }

  function converter(name = "") {
    name = name
      .trim()
      .toLowerCase()

    if (name.includes(" ") === false) return toNumber(name)

    let total = 0
    let partial = 0
    let partialHasChanged = false

    name
      .split(PORTUGUESE_NUMERAL_SEPARATOR_REGEX)
      .forEach((label) => {
        if (PortugueseGroupsNamesMap.has(label)) {
          const factor = toNumber(label)

          if (partial === 0 && partialHasChanged === false)
            partial = 1

          partial *= factor
          total += partial
          partial = 0
          partialHasChanged = false
        } else {
          partial += toNumber(label)
          partialHasChanged = true
        }
      })

    return total + partial
  }

  return Object.freeze({ convert: converter.bind(PortugueseNumeralNomenclatureConverter) })
}