lib/valvat/checksum/es.rb
# frozen_string_literal: true
class Valvat
module Checksum
class ES < Base
NATURAL_PERSON_CHARS = %w[T R W A G M Y F P D X B N J Z S Q V H L C K E].freeze
NATURAL_PERSON_EXP = /\A[KLMXYZ\d]/.freeze
LEGAL_PERSON_CHARS = [false] + %w[A B C D E F G H I J]
NIE_DIGIT_BY_LETTER = %w[X Y Z].freeze
GIVEN_CD_IS_A_LETTER_EXP = /[A-Z]\Z/.freeze
LEGAL_PERSON_EXP = /\A[ABCDEFGHJUVNPQRSW]/.freeze
CIF_MUST_BE_A_LETTER_EXP = /\A[NPQRSW]/.freeze
CIF_MUST_BE_A_NUMBER_EXP = /\A[HJUV]/.freeze
SPECIAL_NIF_EXP = /\A[KLM]/.freeze
def validate
passes_special_validations? && possible_check_digits.include?(given_check_digit)
end
private
def passes_special_validations?
!(
# [KLM]: CD first two numerical digits must be between 01 and 56 (both inclusive)
(vat.to_s_wo_country =~ SPECIAL_NIF_EXP &&
(vat.to_s_wo_country[1..2].to_i > 56 || vat.to_s_wo_country[1..2].to_i < 1)) ||
# Exceptions: X0000000T, 00000001R, 00000000T & 99999999R are invalid.
%w[X0000000T 00000001R 00000000T 99999999R].include?(vat.to_s_wo_country)
)
end
def given_check_digit
given_cd_is_a_letter? ? str_wo_country[-1] : super
end
def possible_check_digits
natural_person? ? possible_cd_natural_person : possible_cds_legal_person
end
def possible_cd_natural_person
letter = vat.to_s_wo_country[0]
nie_digit = NIE_DIGIT_BY_LETTER.index(letter)
[NATURAL_PERSON_CHARS["#{nie_digit}#{figures_str}".to_i.modulo(23)]]
end
def possible_cds_legal_person
chk = 10 - sum_of_figures_for_at_es_it_se(reverse_ints: true).modulo(10)
possible_check_digits = []
possible_check_digits << LEGAL_PERSON_CHARS[chk] if cd_can_be_a_letter?
if cd_can_be_a_num?
possible_check_digits << (chk == 10 ? 0 : chk)
end
possible_check_digits
end
def str_wo_country
str = super
str[0] =~ /\d/ ? str : str[1..]
end
def person?
natural_person? || legal_foreign_person?
end
def natural_person?
!!(vat.to_s_wo_country =~ NATURAL_PERSON_EXP)
end
def legal_foreign_person?
!!(vat.to_s_wo_country =~ FOREIGN_LEGAL_PERSON_EXP)
end
def cd_can_be_a_letter?
vat.to_s_wo_country !~ CIF_MUST_BE_A_NUMBER_EXP
end
def cd_can_be_a_num?
vat.to_s_wo_country !~ CIF_MUST_BE_A_LETTER_EXP
end
def given_cd_is_a_letter?
!!(vat.to_s_wo_country =~ GIVEN_CD_IS_A_LETTER_EXP)
end
end
end
end