private static UnitTypes defineUnitToBuild(int freeMinerals, int freeGas) {
		// boolean arbiterAllowed =
		// UnitCounter.weHaveBuilding(UnitTypes.Protoss_Arbiter_Tribunal);
		boolean valkyrieAllowed = UnitCounter.weHaveBuilding(UnitTypes.Terran_Control_Tower);
		boolean scienceVesselAllowed = UnitCounter
				.weHaveBuilding(UnitTypes.Terran_Science_Facility);

		// // BATTLECRUISER
		// if (arbiterAllowed && xvr.countUnitsOfType(BATTLECRUISER) <
		// MINIMUM_BATTLECRUISERS) {
		// return BATTLECRUISER;
		// }

		// SCIENCE VESSEL
		if (scienceVesselAllowed && TerranScienceVessel.getNumberOfUnits() < MIN_VESSELS) {
			return SCIENCE_VESSEL;
		}

		// VALKYRIE
		if (valkyrieAllowed
				&& UnitCounter.getNumberOfUnitsCompleted(UnitTypes.Terran_Valkyrie) <= 3) {
			return VALKYRIE;
		}

		// WRAITH
		if (UnitCounter.getNumberOfUnits(WRAITH) > MAX_WRAITHS) {
			return WRAITH;
		}

		return null;

		// // VALKYRIE
		// if (UnitCounter.getNumberOfUnits(VALKYRIE) < MINIMUM_VALKYRIES
		// || (UnitCounter.countAirUnitsNonValkyrie() *
		// VALKYRIES_PER_OTHER_AIR_UNIT < UnitCounter
		// .getNumberOfUnits(VALKYRIE))) {
		// return VALKYRIE;
		// }

		// return null;
	}