Function GetTownRoadTypeFirstIntroductionDate

src/town_cmd.cpp:995–1009

* Get the calendar date of the earliest town-buildable road type. * @return introduction date of earliest road type, or INT32_MAX if none available. */

 * @return introduction date of earliest road type, or INT32_MAX if none available.
 */
static TimerGameCalendar::Date GetTownRoadTypeFirstIntroductionDate()
{
	const RoadTypeInfo *best = nullptr;
	for (RoadType rt : GetMaskForRoadTramType(RTT_ROAD)) {
		const RoadTypeInfo *rti = GetRoadTypeInfo(rt);

		if (!rti->flags.Test(RoadTypeFlag::TownBuild)) continue; // Town can't build this road type.

		if (best != nullptr && rti->introduction_date >= best->introduction_date) continue;
		best = rti;
	}

	if (best == nullptr) return TimerGameCalendar::Date(INT32_MAX);
	return best->introduction_date;
}

/**
 * Check if towns are able to build road.