Function CmdBuildRoadDepot

src/road_cmd.cpp:1137–1192

* Build a road depot. * @param tile tile where to build the depot * @param flags operation to perform * @param rt road type * @param dir entrance direction * @return the cost of this operation or an error * * @todo When checking for the tile slope, * distinguish between "Flat land required" and "land sloped in wrong direction" */

 * distinguish between "Flat land required" and "land sloped in wrong direction"
 */
CommandCost CmdBuildRoadDepot(DoCommandFlags flags, TileIndex tile, RoadType rt, DiagDirection dir)
{
	if (!ValParamRoadType(rt) || !IsValidDiagDirection(dir)) return CMD_ERROR;

	CommandCost cost(EXPENSES_CONSTRUCTION);

	Slope tileh = GetTileSlope(tile);
	if (tileh != SLOPE_FLAT) {
		if (!_settings_game.construction.build_on_slopes || !CanBuildDepotByTileh(dir, tileh)) {
			return CommandCost(STR_ERROR_FLAT_LAND_REQUIRED);
		}
		cost.AddCost(_price[PR_BUILD_FOUNDATION]);
	}

	/* Allow the user to rotate the depot instead of having to destroy it and build it again */
	bool rotate_existing_depot = false;
	if (IsRoadDepotTile(tile) && (HasRoadTypeTram(tile) ? rt == GetRoadTypeTram(tile) : rt == GetRoadTypeRoad(tile)))
	{
		CommandCost ret = CheckTileOwnership(tile);
		if (ret.Failed()) return ret;

		if (dir == GetRoadDepotDirection(tile)) return CommandCost();

		ret = EnsureNoVehicleOnGround(tile);
		if (ret.Failed()) return ret;

		rotate_existing_depot = true;
	}

	if (!rotate_existing_depot) {
		cost.AddCost(Command<CMD_LANDSCAPE_CLEAR>::Do(flags, tile));
		if (cost.Failed()) return cost;

		if (IsBridgeAbove(tile)) return CommandCost(STR_ERROR_MUST_DEMOLISH_BRIDGE_FIRST);

		if (!Depot::CanAllocateItem()) return CMD_ERROR;
	}

	if (flags.Test(DoCommandFlag::Execute)) {
		if (rotate_existing_depot) {
			SetRoadDepotExitDirection(tile, dir);
		} else {
			Depot *dep = new Depot(tile);
			MakeRoadDepot(tile, _current_company, dep->index, dir, rt);
			MakeDefaultName(dep);

			/* A road depot has two road bits. */
			UpdateCompanyRoadInfrastructure(rt, _current_company, ROAD_DEPOT_TRACKBIT_FACTOR);
		}

		MarkTileDirtyByTile(tile);
	}

	cost.AddCost(_price[PR_BUILD_DEPOT_ROAD]);
	return cost;
}

static CommandCost RemoveRoadDepot(TileIndex tile, DoCommandFlags flags)