otoplastik_customer.rb

class OtoplastikCustomer < Customer
  def otoplastik?
    true
  end

  def prices(article)
    price_base = OtoplastikArticlePrice.where(otoplastik_article_id: article.id)
    [id, price_group, price_list].map{|i| price_base.where(mechant_code: i)}.find(&:exists?)
  end
end