class Quickbooks::Model::TaxService

def check_details_item
  if tax_rate_details.blank?
    errors.add(:tax_rate_details, "must have at least one item")
  else
    tax_rate_details.each do |line|
      unless line.valid?
        errors.add(:base, line.errors.full_messages.join(', '))
      end
    end
    names = tax_rate_details.map(&:tax_rate_name).uniq
    if names.size < tax_rate_details.size
      errors.add(:tax_rate_name, "Duplicate Tax Rate Name")
    end
  end
end