def update_discounts(current_user)
    ### this is ugly, but necessary due to the many variations of discounting
    ###   Essentially, count spaces in the cart, spaces the user has reserved in previous current
    ###   orders, and then calculate the cart spaces that have not been previously reserved
    cart_discounts = 0
    cart_spaces = line_items.select { |i| i.billable_type == "Space" }
    cart_space_ids = cart_spaces.collect { |s| s.billable_id }
    cart_space_count = cart_spaces.size
    order_spaces = Order.user(current_user.id).status("paid","awaiting_payment","confirmed").collect { |o| o.get_reservations }.flatten
    order_space_ids = order_spaces.collect { |s| s.billable_id }
    order_space_count = order_spaces.size
    new_spaces = cart_space_ids - order_space_ids
    new_space_count = new_spaces.size


    ### This section actually determines how many discounts to be applied
    if order_space_count > 0
      if cart_space_count == order_space_count && new_space_count == 0
        cart_discounts = cart_space_count - 1
      else
        cart_discounts = new_space_count
      end
    elsif cart_space_count > 1
      cart_discounts = cart_space_count - 1
    end
    Rails.logger.warn("Inside update_discounts: CSC: #{cart_space_count} OSC: #{order_space_count} NSC: #{new_space_count} CD: #{cart_discounts}")
    ### And this section applies the appropriate discount or removes it, as applicable
    multispace_discount = line_items.select { |li| li.billable == Product.msd.first }.first
    if multispace_discount
      Rails.logger.warn("Inside if msd: CD: #{cart_discounts}, MSD is a #{multispace_discount.class}")
      if cart_discounts < 1
        multispace_discount.destroy
      else
        multispace_discount.update_attribute(:quantity, cart_discounts)
      end
    else
      unless cart_discounts < 1
        self.line_items << LineItem.new(:price => Product.msd.first.price,
                             :quantity => cart_discounts,
                             :billable => Product.msd.first)
      end
    end
  end