Method GetCapacityString

src/vehicle_gui.cpp:1006–1037

* Gets the #StringID to use for displaying capacity. * @param option Cargo and cargo subtype to check for capacity. * @return INVALID_STRING_ID if there is no capacity. StringID to use in any other case. * @post String parameters have been set. */

	 * @post String parameters have been set.
	 */
	std::string GetCapacityString(const RefitOption &option) const
	{
		assert(_current_company == _local_company);
		auto [cost, refit_capacity, mail_capacity, cargo_capacities] = Command<CMD_REFIT_VEHICLE>::Do(DoCommandFlag::QueryCost, this->selected_vehicle, option.cargo, option.subtype, this->auto_refit, false, this->num_vehicles);

		if (cost.Failed()) return {};

		Money money = cost.GetCost();
		if (mail_capacity > 0) {
			if (this->order != INVALID_VEH_ORDER_ID) {
				/* No predictable cost */
				return GetString(STR_PURCHASE_INFO_AIRCRAFT_CAPACITY, option.cargo, refit_capacity, GetCargoTypeByLabel(CT_MAIL), mail_capacity);
			}

			if (money <= 0) {
				return GetString(STR_REFIT_NEW_CAPACITY_INCOME_FROM_AIRCRAFT_REFIT, option.cargo, refit_capacity, GetCargoTypeByLabel(CT_MAIL), mail_capacity, -money);
			}

			return GetString(STR_REFIT_NEW_CAPACITY_COST_OF_AIRCRAFT_REFIT, option.cargo, refit_capacity, GetCargoTypeByLabel(CT_MAIL), mail_capacity, money);
		}

		if (this->order != INVALID_VEH_ORDER_ID) {
			/* No predictable cost */
			return GetString(STR_PURCHASE_INFO_CAPACITY, option.cargo, refit_capacity, STR_EMPTY);
		}

		if (money <= 0) {
			return GetString(STR_REFIT_NEW_CAPACITY_INCOME_FROM_REFIT, option.cargo, refit_capacity, -money);
		}

		return GetString(STR_REFIT_NEW_CAPACITY_COST_OF_REFIT, option.cargo, refit_capacity, money);
	}

	void DrawWidget(const Rect &r, WidgetID widget) const override
	{