japaneseNumeral.mjs

import { normalize, splitLargeNumber, largeNumbers, n2kan } from './utils.mjs'
import japaneseNumerics from './japaneseNumerics.mjs'

export function kanji2number(japanese/*: string*/) {
  japanese = normalize(japanese)

  if (japanese.match('〇') || japanese.match(/^[〇一二三四五六七八九]+$/)) {
    for (const key in japaneseNumerics) {
      const reg = new RegExp(key, 'g')
      japanese = japanese.replace(reg, japaneseNumerics[key].toString())
    }

    return Number(japanese)
  } else {
    let number = 0
    const numbers = splitLargeNumber(japanese)

    // 万以上の数字を数値に変換
    for (const key in largeNumbers) {
      if (numbers[key]) {
        const n = largeNumbers[key] * numbers[key]
        number = number + n
      }
    }

    if (!Number.isInteger(number) || !Number.isInteger(numbers['千'])) {
      throw new TypeError('The attribute of kanji2number() must be a Japanese numeral as integer.')
    }

    // 千以下の数字を足す
    return number + numbers['千']
  }
}


export function number2kanji(num/*: number*/) {
  if (!num.toString().match(/^[0-9]+$/)) {
    throw new TypeError('The attribute of number2kanji() must be integer.')
  }

  const kanjiNumbers = Object.keys(japaneseNumerics)
  let number = num
  let kanji = ''

  // 万以上の数字を漢字に変換
  for (const key in largeNumbers) {
    const n = Math.floor(number / largeNumbers[key])
    if (n) {
      number = number - (n * largeNumbers[key])
      kanji = `${kanji}${n2kan(n)}${key}`
    }
  }

  if (number) {
    kanji = `${kanji}${n2kan(number)}`
  }

  return kanji
}

export function findKanjiNumbers(text/*: string*/) {
  const basePattern = '([0-9０-９一二三四五六七八九壱壹弐貳貮参參肆伍陸漆捌玖]*(千|阡|仟))?([0-9０-９一二三四五六七八九壱壹弐貳貮参參肆伍陸漆捌玖]*(百|陌|佰))?([0-9０-９一二三四五六七八九壱壹弐貳貮参參肆伍陸漆捌玖]*(十|拾))?([0-9０-９〇一二三四五六七八九壱壹弐貳貮参參肆伍陸漆捌玖]+)?'
  const pattern = `(${basePattern}兆)?(${basePattern}億)?(${basePattern}(万|萬))?${basePattern}`
  const regex = new RegExp(pattern, 'g')
  const match = text.match(regex)
  if (match) {
    return match.filter((item) => {
      if (item.length && '兆' !== item && '億' !== item && '万' !== item && '萬' !== item) {
        return true
      } else {
        return false
      }
    })
  } else {
    return []
  }
}