#openttdcoop

function buildTownStation(town, cargoClass, stationTile, otherTown) {
        local stationId = (stationTile == null) ?  AIStation.STATION_NEW : AIStation.GetStationID(stationTile);
        local vehicleType = (cargoClass == AICargo.CC_MAIL) ? AIRoad.ROADVEHTYPE_TRUCK : AIRoad.ROADVEHTYPE_BUS;
//		local max_spread = AIController.GetSetting("station_spread") && AIGameSettings.GetValue("distant_join_stations");

local cargoType = Utils.getCargoId(cargoClass);

local tileList = AITileList();
        if(stationTile == null) {
            //stationTile = AIStation.STATION_NEW;
            //build square around @town and find suitable tiles for truck stops
            local rectangleCoordinates = estimateTownRectangle(town);

tileList.AddRectangle(rectangleCoordinates[0], rectangleCoordinates[1]);
			
			for(local tile = tileList.Begin(); tileList.HasNext(); tile = tileList.Next()) {
				if (Utils.AreOtherStationsNearby(tile, cargoClass, stationId)) {
				    tileList.RemoveTile(tile);
				}
            }
			
            //valuate and sort by the number of cargo tiles the station covers
            tileList.Valuate(Utils.valuateTruckStopTile, cargoClass, stationId, cargoType);
            tileList.RemoveValue(0);
            tileList.Sort(AIList.SORT_BY_VALUE, false); //starts from corners if without sort
        }
        else {
            //expanding existing station
            if(!AIStation.IsValidStation(stationId)) {
                return null;
            }

local squareSize = AIGameSettings.GetValue("station_spread");

AILog.Info("AddRectangle");
            tileList.AddRectangle(Utils.getValidOffsetTile(stationTile, -1 * squareSize, -1 * squareSize),
                Utils.getValidOffsetTile(stationTile, squareSize, squareSize));
				
			AILog.Info("AreOtherStationsNearby");
			for(local tile = tileList.Begin(); tileList.HasNext(); tile = tileList.Next()) {
				if (Utils.AreOtherStationsNearby(tile, cargoClass, stationId)) {
				    tileList.RemoveTile(tile);
				}
            }
			AILog.Info("Valuate tiles");
            tileList.Valuate(Utils.valuateTruckStopTile, cargoClass, stationId, cargoType);
            tileList.RemoveValue(0);
        }

for (local tile = tileList.Begin(); tileList.HasNext(); tile = tileList.Next()) {
		    AILog.Info("cycling tileList");
            //get adjacent tiles
            local adjTileList = Utils.getAdjacentTiles(tile);
            local adjRoadTiles = AITileList();
            adjRoadTiles.AddList(adjTileList);
            adjRoadTiles.Valuate(AIRoad.IsRoadTile);
            adjRoadTiles.KeepValue(1);

AIRoad.SetCurrentRoadType(AIRoad.ROADTYPE_ROAD);
            local adjRoadCount = adjRoadTiles.Count();
			AILog.Info("computing adjacentAirport");
			local adjacentAirport = Utils.checkAdjacentAirport(tile, cargoClass, stationId);

AILog.Info("switching cases");
            switch (adjRoadCount) {
            //case where station tile has no adjacent road tiles
                case 0:
				    /* expanding via this case can be too slow */
				    if (stationTile != null) {
					    continue;
					}
					
					local closestAdjTile = null;
                    for (local adjTile = adjTileList.Begin(); adjTileList.HasNext(); adjTile = adjTileList.Next()) {
						if (!AITile.IsBuildable(adjTile) || AITile.GetSlope(adjTile) != AITile.SLOPE_FLAT) {
						    continue;
						}
						
						if (closestAdjTile == null) {
					        closestAdjTile = adjTile;
						}
						
						if (AITown.GetDistanceManhattanToTile(otherTown, adjTile) < closestAdjTile) {
						    closestAdjTile = adjTile;
						}
					}
					
					if (closestAdjTile == null) {
					    continue;
					}

local counter = 0;
					do {
                        if (!TestBuildRoadStation().TryBuild(tile, closestAdjTile, vehicleType, adjacentAirport)) {
                            //if((AIError.GetLastErrorString() != "ERR_ALREADY_BUILT") && (AIError.GetLastErrorString() != "ERR_PRECONDITION_FAILED")) {
                                //AILog.Warning("Couldnt build station! " + AIError.GetLastErrorString());
                            //}
							++counter;
						}
						else {
						    break;
						}
                        AIController.Sleep(1);
                    } while(counter < 1);						
					if(counter == 1) {
				        continue;
					}
					
                    if (stationTile != null) {						
					    if (buildRoad(tile, AITown.GetLocation(otherTown), true) == null) {
						    local counter = 0;
							do {
							   	if (!TestRemoveRoadStation().TryRemove(tile)) {
								    ++counter;
								}
								else {
//									AILog.Warning("case" + adjRoadCount + "; Removed road station tile at " + tile);
			    			        break;
								}
								AIController.Sleep(1);
							} while(counter < (stationTile == null ? 500 : 1));
							if (counter == (stationTile == null ? 500 : 1)) {
							    AILog.Error("Failed to remove road station tile at " + tile + " - " + AIError.GetLastErrorString());
							    continue; // TODO: station should have been removed by now, but it wasn't!
							} else {
							    continue;
							}
						}
					}

AILog.Info("Station built in " + AITown.GetName(town) + " at tile " + tile + "! case" + adjRoadCount);
                    //AISign.BuildSign(tile, "" + adjRoadCount);
                    return tile;

break;

case 1:

local adjTile = adjRoadTiles.Begin();
						
				    if (AIRoad.IsDriveThroughRoadStationTile(adjTile)) {
					    continue;
					}
						
                    local heighDifference = abs(AITile.GetMaxHeight(tile) - AITile.GetMaxHeight(adjTile));

if(heighDifference != 0) {
                        continue;
                    }

local counter = 0;
					do {
					    /* Try to build a road station or a drive through road station */
                        if (!TestBuildRoadStation().TryBuild(tile, adjTile, vehicleType, adjacentAirport) || AIRoad.IsRoadTile(tile)
						    && !TestBuildDriveThroughRoadStation().TryBuild(tile, adjTile, vehicleType, adjacentAirport)) {
						    ++counter;
						}
						else {
						    break;
						}
						AIController.Sleep(1);
                    } while(counter < 1);
					if (counter == 1) {
					    /* Failed to build station, try the next location */
					    continue;
					}
                    else {
					    /* With the road station built, try to connect it to the road */
						local drivethrough = AIRoad.IsDriveThroughRoadStationTile(tile);
                        local counter = 0;
                        do {
                            if(!TestBuildRoad().TryBuild(tile, adjTile) && AIError.GetLastErrorString() != "ERR_ALREADY_BUILT") {
                                ++counter;
                            }
                            else {
                                break;
                            }
							AIController.Sleep(1);
                        } while(counter < (stationTile == null ? 500 : 1));
                        if(counter == (stationTile == null ? 500 : 1)) {
						    /* Failed to connect road to the station. Try to remove the station we had built then */
                            local counter = 0;
							do {
                                if (!TestRemoveRoadStation().TryRemove(tile)) {
								    ++counter;
								}
								else {
								    if (drivethrough) {
//								        AILog.Warning("case" + adjRoadCount + "; Removed drive through station tile at " + tile);
									} else {
//									    AILog.Warning("case" + adjRoadCount + "; Removed road station tile at " + tile);
									}
								    break;
								}
							    AIController.Sleep(1);
							} while (counter < (stationTile == null ? 500 : 1));
							if (counter == (stationTile == null ? 500 : 1)) {
							    if (drivethrough) {
								    AILog.Error("Failed to remove drive through station tile at " + tile + " - " + AIError.GetLastErrorString());
								} else {
								    AILog.Error("Failed to remove road station tile at " + tile + " - " + AIError.GetLastErrorString());
								}
							    continue; // TODO: station should have been removed by now, but it wasn't!
							} else {
							    /* The station was successfully removed after failing to connect it to the road. Try it all over again in the next location */
							    continue;
							}
                        }
                        else {
						    /* The road was successfully connected to the station */
							if (!AIRoad.IsDriveThroughRoadStationTile(tile)) {
                                AILog.Info("Station built in " + AITown.GetName(town) + " at tile " + tile + "! case" + adjRoadCount);
							} else {
								AILog.Info("Drivethrough station built in " + AITown.GetName(town) + " at tile " + tile + "! case" + adjRoadCount);
							}
                            //AISign.BuildSign(tile, "" + adjRoadCount);
                            return tile;
                        }
                    }

break;

case 2:
                    local adjTile = adjRoadTiles.Begin();
                    local nextAdjTile = adjRoadTiles.Next();

//dont build drivethrough station next to regular station
                    adjTileList.RemoveItem(adjTile);
                    adjTileList.RemoveItem(nextAdjTile);
                    local found = false;
                    for(local t = adjTileList.Begin(); adjTileList.HasNext(); t = adjTileList.Next()) {
                        if (AIRoad.IsRoadStationTile(t) && AIRoad.GetRoadStationFrontTile(t) == tile ||
						    AIRoad.IsRoadDepotTile(t) && AIRoad.GetRoadDepotFrontTile(t) == tile) {
                            found = true;
                            break;
                        }
                    }
                    if(found) {
                        continue;
                    }

local heighDifference = abs(AITile.GetMaxHeight(nextAdjTile) - AITile.GetMaxHeight(adjTile));
                    if(heighDifference != 0) {
                        continue;
                    }

//check whether adjacent tiles are opposite
                    local opposite = false;
                    if((AIMap.GetTileX(adjTile) == AIMap.GetTileX(nextAdjTile))
                        || (AIMap.GetTileY(adjTile) == AIMap.GetTileY(nextAdjTile))) {
                            opposite = true;
                    }

if(AIRoad.IsRoadTile(tile)) {
                        if(!opposite) {
                            continue;
                        }
                    }

if(opposite) {
					    local counter = 0;
					    do {
                            if (!TestBuildDriveThroughRoadStation().TryBuild(tile, adjTile, vehicleType, adjacentAirport)) {
                                if((AIError.GetLastErrorString() != "ERR_ALREADY_BUILT") && (AIError.GetLastErrorString() != "ERR_PRECONDITION_FAILED")) {
                                    if(AIError.GetLastErrorString() != "ERR_LOCAL_AUTHORITY_REFUSES") {
                                        //AILog.Warning("Couldnt build station! " + AIError.GetLastErrorString());
                                    }
                                }
								++counter;
							}
							else {
							    break;
							}
							AIController.Sleep(1)
						} while(counter < 1);
						if (counter == 1) {
                            continue;
                        }
                        else {
                            local counter = 0;
                            do {
                                if(!TestBuildRoad().TryBuild(adjTile, nextAdjTile) && AIError.GetLastErrorString() != "ERR_ALREADY_BUILT") {
                                    ++counter;
                                }
                                else {
                                    break;
                                }
								AIController.Sleep(1);
                            } while(counter < (stationTile == null ? 500 : 1));
                            if(counter == (stationTile == null ? 500 : 1)) {
							    local counter = 0;
								do {
								    if (!TestRemoveRoadStation().TryRemove(tile)) {
								        ++counter;
								    }
								    else {
//									    AILog.Warning("case" + adjRoadCount + "; Removed drive through station tile at " + tile);
									    break;
								    }
								    AIController.Sleep(1);
							    } while(counter < (stationTile == null ? 500 : 1));
							    if (counter == (stationTile == null ? 500 : 1)) {
								    AILog.Error("Failed to remove drive through station tile at " + tile + " - " + AIError.GetLastErrorString());
    							    continue; // TODO: station should have been removed by now, but it wasn't!
                                } else {
								    continue;
								}
							}
                            else {
                                AILog.Info("Drivethrough station built in " + AITown.GetName(town) + " at tile " + tile + "! case" + adjRoadCount);
                                //AISign.BuildSign(tile, "" + adjRoadCount);
                                return tile;
                            }
                        }
                    }
                    //similar to case 1 if adjacent tiles are not opposite
                    else {
					    local counter = 0;
						do {
                            if (!TestBuildRoadStation().TryBuild(tile, adjTile, vehicleType, adjacentAirport)) {
                                if((AIError.GetLastErrorString() != "ERR_ALREADY_BUILT") && (AIError.GetLastErrorString() != "ERR_PRECONDITION_FAILED")) {
                                    if(AIError.GetLastErrorString() != "ERR_LOCAL_AUTHORITY_REFUSES") {
                                        //AILog.Warning("Couldnt build station! " + AIError.GetLastErrorString());
                                    }
                                }
								++counter;
							}
							else {
							    break;
							}
							AIController.Sleep(1);
						} while(counter < 1);
						if (counter == 1) {
						    continue;
                        }
                        else {
                            local counter = 0;
                            do {
                                if(!TestBuildRoad().TryBuild(tile, adjTile) && AIError.GetLastErrorString() != "ERR_ALREADY_BUILT") {
                                    ++counter;
                                }
                                else {
                                    break;
                                }
								AIController.Sleep(1);
                            } while(counter < (stationTile == null ? 500 : 1));
                            if(counter == (stationTile == null ? 500 : 1)) {
							    local counter = 0;
								do {
								    if (!TestRemoveRoadStation().TryRemove(tile)) {
									    ++counter;
									}
									else {
//									    AILog.Warning("case" + adjRoadCount + "; Removed road station tile at " + tile);
										break;
									}
									AIController.Sleep(1);
								} while(counter < (stationTile == null ? 500 : 1));
								if (counter == (stationTile == null ? 500 : 1)) {
								    AILog.Error("Failed to remove road station tile at " + tile + " - " + AIError.GetLastErrorString());
								    continue; // TODO: station should have been removed by now, but it wasn't!
								} else {
                                    continue;
								}
                            }
                            else {
                                AILog.Info("Station built in " + AITown.GetName(town) + " at tile " + tile + "! case" + adjRoadCount);
                                //AISign.BuildSign(tile, "" + adjRoadCount);
                                return tile;
                            }
                        }
                    }

break;

case 3:
                case 4:
                    //similar to case 2 but always builds drivethrough station
                    AIRoad.SetCurrentRoadType(AIRoad.ROADTYPE_ROAD);

if(AIRoad.IsRoadTile(tile)) {
                        continue;
                    }

//check whether adjacent tiles are opposite
					local adjTile = Utils.getOffsetTile(tile, -1, 0);
					local nextAdjTile = Utils.getOffsetTile(tile, 1, 0);
					if (!(adjRoadTiles.HasItem(adjTile) && adjRoadTiles.HasItem(nextAdjTile))) {
						adjTile = Utils.getOffsetTile(tile, 0, -1);
						nextAdjTile = Utils.getOffsetTile(tile, 0, 1);
					}

local heighDifference = abs(AITile.GetMaxHeight(nextAdjTile) - AITile.GetMaxHeight(adjTile));
                    if(heighDifference != 0) {
                        continue;
                    }

local counter = 0;
					do {
					    if (!TestBuildDriveThroughRoadStation().TryBuild(tile, adjTile, vehicleType, adjacentAirport)) {
                            if((AIError.GetLastErrorString() != "ERR_ALREADY_BUILT") && (AIError.GetLastErrorString() != "ERR_PRECONDITION_FAILED")) {
                                if(AIError.GetLastErrorString() != "ERR_LOCAL_AUTHORITY_REFUSES") {
                                    //AILog.Warning("Couldnt build station! " + AIError.GetLastErrorString());
                                }
                            }
							++counter;
						}
						else {
						    break;
						}
						AIController.Sleep(1);
					} while(counter < 1);
					if (counter == 1) {
                        continue;
                    }
                    else {
                        local counter = 0;
                        do {
                            if(!TestBuildRoad().TryBuild(adjTile, nextAdjTile) && AIError.GetLastErrorString() != "ERR_ALREADY_BUILT") {
                                ++counter;
                            }
                            else {
                                break;
                            }
							AIController.Sleep(1);
                        } while(counter < (stationTile == null ? 500 : 1));
                        if(counter == (stationTile == null ? 500 : 1)) {
						    local counter = 0;
							do {
							    if (!TestRemoveRoadStation().TryRemove(tile)) {
								    ++counter;
								}
								else {
//								    AILog.Warning("case" + adjRoadCount + "; Removed drive through station tile at " + tile);
									break;
								}
							    AIController.Sleep(1);
						    } while (counter < stationTile == null ? 500 : 1);
							if (counter == (stationTile == null ? 500 : 1)) {
							    AILog.Error("Failed to remove drive through station tile at " + tile + " - " + AIError.GetLastErrorString());
							    continue; // TODO: station should have been removed by now, but it wasn't!
							} else {
                                continue;
							}
                        }
                        else {
                            AILog.Info("Drivethrough station built in " + AITown.GetName(town) + " at tile " + tile + "! case" + adjRoadCount);
                            //AISign.BuildSign(tile, "" + adjRoadCount);
                            return tile;
                        }
                    }

break;

default:
                    break;
            }
        }

return null;
    }

Mark as private