Function CmdBuildDock

src/station_cmd.cpp:2892–2978

* Build a dock/haven. * @param flags operation to perform * @param tile tile where dock will be built * @param station_to_join station ID to join (NEW_STATION if build new one) * @param adjacent allow docks directly adjacent to other docks. * @return the cost of this operation or an error */

 * @return the cost of this operation or an error
 */
CommandCost CmdBuildDock(DoCommandFlags flags, TileIndex tile, StationID station_to_join, bool adjacent)
{
	bool reuse = (station_to_join != NEW_STATION);
	if (!reuse) station_to_join = StationID::Invalid();
	bool distant_join = (station_to_join != StationID::Invalid());

	if (distant_join && (!_settings_game.station.distant_join_stations || !Station::IsValidID(station_to_join))) return CMD_ERROR;

	DiagDirection direction = GetInclinedSlopeDirection(GetTileSlope(tile));
	if (direction == INVALID_DIAGDIR) return CommandCost(STR_ERROR_SITE_UNSUITABLE);
	direction = ReverseDiagDir(direction);

	/* Docks cannot be placed on rapids */
	if (HasTileWaterGround(tile)) return CommandCost(STR_ERROR_SITE_UNSUITABLE);

	CommandCost ret = CheckIfAuthorityAllowsNewStation(tile, flags);
	if (ret.Failed()) return ret;

	ret = IsDockBridgeAboveOk(tile, to_underlying(direction));
	if (ret.Failed()) return ret;

	CommandCost cost(EXPENSES_CONSTRUCTION, _price[PR_BUILD_STATION_DOCK]);
	ret = Command<CMD_LANDSCAPE_CLEAR>::Do(flags, tile);
	if (ret.Failed()) return ret;
	cost.AddCost(ret.GetCost());

	TileIndex tile_cur = tile + TileOffsByDiagDir(direction);

	if (!HasTileWaterGround(tile_cur) || !IsTileFlat(tile_cur)) {
		return CommandCost(STR_ERROR_SITE_UNSUITABLE);
	}

	ret = IsDockBridgeAboveOk(tile_cur, GFX_DOCK_BASE_WATER_PART + to_underlying(DiagDirToAxis(direction)));
	if (ret.Failed()) return ret;

	/* Get the water class of the water tile before it is cleared.*/
	WaterClass wc = GetWaterClass(tile_cur);

	bool add_cost = !IsWaterTile(tile_cur);
	ret = Command<CMD_LANDSCAPE_CLEAR>::Do(flags, tile_cur);
	if (ret.Failed()) return ret;
	if (add_cost) cost.AddCost(ret.GetCost());

	tile_cur += TileOffsByDiagDir(direction);
	if (!IsTileType(tile_cur, MP_WATER) || !IsTileFlat(tile_cur)) {
		return CommandCost(STR_ERROR_SITE_UNSUITABLE);
	}

	TileArea dock_area = TileArea(tile + ToTileIndexDiff(_dock_tileoffs_chkaround[direction]),
			_dock_w_chk[direction], _dock_h_chk[direction]);

	/* middle */
	Station *st = nullptr;
	ret = FindJoiningStation(StationID::Invalid(), station_to_join, adjacent, dock_area, &st);
	if (ret.Failed()) return ret;

	/* Distant join */
	if (st == nullptr && distant_join) st = Station::GetIfValid(station_to_join);