# frozen_string_literal: true

# Libs are following this issue: https://github.com/rails/rails/issues/37835
# Rules to generate a CPF https://www.geradorcpf.com/algoritmo_do_cpf.htm

module BraDocuments
  class CNPJGenerator < NationalRegisterBase
    COMPANY_NUMBER_SIZE = 8
    MATRIX_SUBSIDIARY_SIZE = 4

    class << self
      # Generates a random CNPJ document number or add verifying digits to one if it's given.
      # It can return only numbers or formatted with mask
      #
      #  BraDocuments::CNPJGenerator.generate
      #  # => "62885807804809"
      #
      #  BraDocuments::CNPJGenerator.generate(formatted: true)
      #  # => "53.855.973/0664-39"
      #
      #  BraDocuments::CNPJGenerator.generate(company_number: '53855973')
      #  # => "53855973879456"
      #
      #  BraDocuments::CNPJGenerator.generate(company_number: '53855973', formatted: true)
      #  # => "53.855.973/8189-02"
      #
      #  BraDocuments::CNPJGenerator.generate(company_number: '53855973', matrix_subsidiary_number: '0001')
      #  # => "53855973000179"
      #
      #  BraDocuments::CNPJGenerator.generate(
      #    company_number: '53855973',
      #    matrix_subsidiary_number: '0001',
      #    formatted: true
      #    )
      #  # => "53.855.973/0001-79"
      def generate(company_number: nil, matrix_subsidiary_number: nil, formatted: false)
        company_number = number_for('Company', COMPANY_NUMBER_SIZE, company_number)
        matrix_subsidiary_number = number_for('Matrix or subsidiary', MATRIX_SUBSIDIARY_SIZE, matrix_subsidiary_number)
        numbers = company_number + matrix_subsidiary_number

        full_number = complete!(numbers)

        formatted ?  Formatter.format(full_number, as: :cnpj) : full_number
      end

      # Returns if a CPF has a valid verification digit.
      #
      #   BraDocuments::CPFGenerator.valid_verification_digit?(document: '11.111.111/1111-11')
      #   # => false
      #
      #   BraDocuments::CPFGenerator.valid_verification_digit?(document: '20.163.606/0001-55')
      #   # => true
      #
      #   BraDocuments::CPFGenerator.valid_verification_digit?(document: '29432530000190')
      #   # => true
      def valid_verification_digit?(document:)
        raw_document = Formatter.raw(document)
        return false if raw_document.chars.uniq.size == 1

        company_number = raw_document.slice(0..(COMPANY_NUMBER_SIZE - 1))
        matrix_subsidiary_number = raw_document
          .slice(COMPANY_NUMBER_SIZE..(COMPANY_NUMBER_SIZE + MATRIX_SUBSIDIARY_SIZE - 1))
        verified_digit = raw_document.slice(-2..-1)

        generate(company_number: company_number, matrix_subsidiary_number: matrix_subsidiary_number)
          .end_with?(verified_digit)
      end

      private

      def verification_digit_multiplicators_for(numbers)
        (2..(numbers.size - 7)).to_a.reverse + (2..9).to_a.reverse
      end
    end
  end
end