module Concerns
  module Invoice
    module Payable
      extend ActiveSupport::Concern

      included do
        scope :unpaid, -> { where('id NOT IN (SELECT invoice_id FROM account_activities WHERE' \
                              ' invoice_id IS NOT NULL)') }
      end

      def payable?
        unpaid? && not_cancelled?
      end

      def paid?
        account_activity
      end

      def receipt_date
        account_activity.created_at.to_date
      end

      def unpaid?
        !paid?
      end
    end
  end
end