# frozen_string_literal: true

module SecId
  class Base
    CHAR_TO_DIGITS = {
      '0' => 0,      '1' => 1,      '2' => 2,      '3' => 3,      '4' => 4,
      '5' => 5,      '6' => 6,      '7' => 7,      '8' => 8,      '9' => 9,
      'A' => [1, 0], 'B' => [1, 1], 'C' => [1, 2], 'D' => [1, 3], 'E' => [1, 4],
      'F' => [1, 5], 'G' => [1, 6], 'H' => [1, 7], 'I' => [1, 8], 'J' => [1, 9],
      'K' => [2, 0], 'L' => [2, 1], 'M' => [2, 2], 'N' => [2, 3], 'O' => [2, 4],
      'P' => [2, 5], 'Q' => [2, 6], 'R' => [2, 7], 'S' => [2, 8], 'T' => [2, 9],
      'U' => [3, 0], 'V' => [3, 1], 'W' => [3, 2], 'X' => [3, 3], 'Y' => [3, 4], 'Z' => [3, 5],
      '*' => [3, 6], '@' => [3, 7], '#' => [3, 8]
    }.freeze

    CHAR_TO_DIGIT = {
      '0' => 0,  '1' => 1,  '2' => 2,  '3' => 3,  '4' =>  4,
      '5' => 5,  '6' => 6,  '7' => 7,  '8' => 8,  '9' =>  9,
      'A' => 10, 'B' => 11, 'C' => 12, 'D' => 13, 'E' => 14,
      'F' => 15, 'G' => 16, 'H' => 17, 'I' => 18, 'J' => 19,
      'K' => 20, 'L' => 21, 'M' => 22, 'N' => 23, 'O' => 24,
      'P' => 25, 'Q' => 26, 'R' => 27, 'S' => 28, 'T' => 29,
      'U' => 30, 'V' => 31, 'W' => 32, 'X' => 33, 'Y' => 34, 'Z' => 35,
      '*' => 36, '@' => 37, '#' => 38
    }.freeze

    attr_reader :identifier, :check_digit

    def self.valid?(id)
      new(id).valid?
    end

    def self.valid_format?(id)
      new(id).valid_format?
    end

    def self.restore!(id_without_check_digit)
      new(id_without_check_digit).restore!
    end

    def self.check_digit(id)
      new(id).calculate_check_digit
    end

    def initialize(_sec_id_number)
      raise NotImplementedError
    end

    def valid?
      raise NotImplementedError
    end

    def valid_format?
      raise NotImplementedError
    end

    def restore!
      raise NotImplementedError
    end

    def calculate_check_digit
      raise NotImplementedError
    end

    def to_s
      "#{identifier}#{check_digit}"
    end
    alias to_str to_s

    private

    def digitized_identifier
      raise NotImplementedError
    end

    def char_to_digits(char)
      CHAR_TO_DIGITS.fetch(char)
    end

    def char_to_digit(char)
      CHAR_TO_DIGIT.fetch(char)
    end

    def mod_10(sum)
      (10 - (sum % 10)) % 10
    end
  end
end