module NumberToKanji

# File lib/number_to_kanji.rb, line 12
def call(number)
  raise(::TypeError) unless number.is_a?(::Integer)
  raise(::NumberToKanji::Exceptions::NegativeNumberError) if number.negative?

  raise(::RangeError, 'Numbers equal to or larger than 10^24 is not supported.') if number >= ::NumberToKanji::RANGE_END

  return ::NumberToKanji::KANJI_MAP[0] if number.zero?

  # 四桁ごとに区切りつつ、位の小さい順に並んだ配列を作る。
  # 例: 123456789 => [6789, 2345, 1]
  # 例: 100006789 => [6789, 0, 1]
  separated_numbers = number.to_s.chars.reverse.each_slice(4).map(&:reverse).map(&:join).map { |i| Integer(i, 10) }

  kanji_with_unit_numbers =
    separated_numbers.map.with_index do |separated_number, index|
      _kanji_number_with_unit(separated_number, index)
    end

  kanji_with_unit_numbers.reverse.join
end

# File lib/number_to_kanji.rb, line 33
def _kanji_number_with_unit(number, index)
  return if number.zero?

  kanji = ::NumberToKanji::SmallNumberToKanji.call(number)
  unit = ::NumberToKanji::KANJI_UNITS[index]

  "#{kanji}#{unit}"
end

# File lib/number_to_kanji.rb, line 33
def _kanji_number_with_unit(number, index)
  return if number.zero?

  kanji = ::NumberToKanji::SmallNumberToKanji.call(number)
  unit = ::NumberToKanji::KANJI_UNITS[index]

  "#{kanji}#{unit}"
end

# File lib/number_to_kanji.rb, line 12
def call(number)
  raise(::TypeError) unless number.is_a?(::Integer)
  raise(::NumberToKanji::Exceptions::NegativeNumberError) if number.negative?

  raise(::RangeError, 'Numbers equal to or larger than 10^24 is not supported.') if number >= ::NumberToKanji::RANGE_END

  return ::NumberToKanji::KANJI_MAP[0] if number.zero?

  # 四桁ごとに区切りつつ、位の小さい順に並んだ配列を作る。
  # 例: 123456789 => [6789, 2345, 1]
  # 例: 100006789 => [6789, 0, 1]
  separated_numbers = number.to_s.chars.reverse.each_slice(4).map(&:reverse).map(&:join).map { |i| Integer(i, 10) }

  kanji_with_unit_numbers =
    separated_numbers.map.with_index do |separated_number, index|
      _kanji_number_with_unit(separated_number, index)
    end

  kanji_with_unit_numbers.reverse.join
end