class Faker::Internet

def domain_name(subdomain: false, domain: nil)
  with_locale(:en) do
    if domain
      domain
        .split('.')
        .map { |domain_part| Char.prepare(domain_part) }
        .tap do |domain_elements|
          if domain_elements.length < 2
            domain_elements << domain_suffix(safe: true)
          end
          if subdomain && domain_elements.length < 3
            domain_elements.unshift(Char.prepare(domain_word))
          end
        end.join('.')
    else
      [domain_word, domain_suffix(safe: true)].tap do |domain_elements|
        if subdomain
          domain_elements.unshift(Char.prepare(domain_word))
        end
      end.join('.')
    end
  end
end