function WrightAI::checkAdjacentStation(airportTile, airport_type) {
    if (!AIController.GetSetting("station_spread")) {
	    return AIStation.STATION_NEW;
	}

	local tileList = AITileList();
	local spreadrectangle = expandAdjacentStationRect(airportTile, airport_type);
	tileList.AddRectangle(spreadrectangle[0], spreadrectangle[1]);

	tileList.Valuate(Utils.isTileMyStationWithoutAirport);
	tileList.KeepValue(1);
	tileList.Valuate(AIStation.GetStationID);

	local stationList = AIList();
	for(local tile = tileList.Begin(); tileList.HasNext(); tileList.Next()) {
		stationList.AddItem(tileList.GetValue(tile), AITile.GetDistanceManhattanToTile(tile, airportTile));
	}
	
	local spread_rad = AIGameSettings.GetValue("station_spread");
	local airport_x = AIAirport.GetAirportWidth(airport_type);
	local airport_y = AIAirport.GetAirportHeight(airport_type);
	
	local list = AIList();
	list.AddList(stationList);
	for (local stationId = stationList.Begin(); stationList.HasNext(); stationId = stationList.Next()) {
	    local stationTiles = AITileList_StationType(stationId, AIStation.STATION_ANY);
	    local station_top_x = AIMap.GetTileX(AIBaseStation.GetLocation(stationId));
		local station_top_y = AIMap.GetTileY(AIBaseStation.GetLocation(stationId));
		local station_bot_x = AIMap.GetTileX(AIBaseStation.GetLocation(stationId));
		local station_bot_y = AIMap.GetTileY(AIBaseStation.GetLocation(stationId));
		for (local tile = stationTiles.Begin(); stationTiles.HasNext(); tile = stationTiles.Next()) {
		    local tile_x = AIMap.GetTileX(tile);
			local tile_y = AIMap.GetTileY(tile);
		    if (tile_x < station_top_x) {
			    station_top_x = tile_x;
			}
			if (tile_x > station_bot_x) {
			    station_bot_x = tile_x;
			}
			if (tile_y < station_top_y) {
			    station_top_y = tile_y;
			}
			if (tile_y > station_bot_y) {
			    station_bot_y = tile_y;
			}
		}
		local st_size_x = station_bot_x - station_top_x + 1;
		local st_size_y = station_bot_y - station_top_y + 1;
//		AILog.Info(AIStation.GetName(stationId) + " station size = " + st_size_x + "*" + st_size_y);
		if (st_size_x + airport_x > spread_rad || st_size_y + airport_y > spread_rad) {
		    list.RemoveItem(stationId);
		}
	}
	list.Sort(AIList.SORT_BY_VALUE, true);

	local adjacentStation = AIStation.STATION_NEW;
	if(list.Count()) {
		adjacentStation = list.Begin();
//		AILog.Info("adjacentStation = " + AIStation.GetName(adjacentStation) + " ; airportTile = " + AIMap.GetTileX(airportTile) + "," + AIMap.GetTileY(airportTile));
	}

	return adjacentStation;
}

function WrightAI::expandAdjacentStationRect(airportTile, airport_type) {
    local spread_rad = AIGameSettings.GetValue("station_spread");
    local airport_x = AIAirport.GetAirportWidth(airport_type);
	local airport_y = AIAirport.GetAirportHeight(airport_type);
	
	local remaining_x = spread_rad - airport_x;
	local remaining_y = spread_rad - airport_y;
	
	local tile_top_x = AIMap.GetTileX(airportTile);
	local tile_top_y = AIMap.GetTileY(airportTile);
	local tile_bot_x = AIMap.GetTileX(airportTile) + airport_x - 1;
	local tile_bot_y = AIMap.GetTileY(airportTile) + airport_y - 1;
	
	for (local x = remaining_x; x > 0; x--) {
	    if (AIMap.IsValidTile(AIMap.GetTileIndex(tile_top_x - 1, tile_top_y))) {
		    tile_top_x = tile_top_x - 1;
		}
		if (AIMap.IsValidTile(AIMap.GetTileIndex(tile_bot_x + 1, tile_bot_y))) {
		    tile_bot_x = tile_bot_x + 1;
		}
	}
	
	for (local y = remaining_y; y > 0; y--) {
	    if (AIMap.IsValidTile(AIMap.GetTileIndex(tile_top_x, tile_top_y - 1))) {
		    tile_top_y = tile_top_y - 1;
		}
		if (AIMap.IsValidTile(AIMap.GetTileIndex(tile_bot_x, tile_bot_y + 1))) {
		    tile_bot_y = tile_bot_y + 1;
		}
	}
	
//	AILog.Info("spreadrectangle top = " + tile_top_x + "," + tile_top_y + " ; spreadrectangle bottom = " + tile_bot_x + "," + tile_bot_y);
	return [AIMap.GetTileIndex(tile_top_x, tile_top_y), AIMap.GetTileIndex(tile_bot_x, tile_bot_y)];
}

function WrightAI::TownAirportRadRect(airport_type, town_id) {
    local town_rectangle = BuildManager.estimateTownRectangle(town_id);
	
	local town_top_x = AIMap.GetTileX(town_rectangle[0]);
	local town_top_y = AIMap.GetTileY(town_rectangle[0]);	
	local town_bot_x = AIMap.GetTileX(town_rectangle[1]);
	local town_bot_y = AIMap.GetTileY(town_rectangle[1]);
//	AILog.Info("top tile was " + town_top_x + "," + town_top_y + " bottom tile was " + town_bot_x + "," + town_bot_y);
	
	local airport_x = AIAirport.GetAirportWidth(airport_type);
	local airport_y = AIAirport.GetAirportHeight(airport_type);
	local airport_rad = AIAirport.GetAirportCoverageRadius(airport_type);
	
	for (local x = airport_x; x > 1; x--) {
		if (AIMap.IsValidTile(AIMap.GetTileIndex(town_top_x - 1, town_top_y))) {
		    town_top_x = town_top_x - 1;
		}
	}
	
	for (local y = airport_y; y > 1; y--) {
	    if (AIMap.IsValidTile(AIMap.GetTileIndex(town_top_x, town_top_y - 1))) {
		    town_top_y = town_top_y - 1;
		}
	}
	
	for (local r = airport_rad; r > 0; r--) {
	    if (AIMap.IsValidTile(AIMap.GetTileIndex(town_top_x - 1, town_top_y))) {
		    town_top_x = town_top_x - 1;
		}
        if (AIMap.IsValidTile(AIMap.GetTileIndex(town_top_x, town_top_y - 1))) {
		    town_top_y = town_top_y - 1;
		}
	    if (AIMap.IsValidTile(AIMap.GetTileIndex(town_bot_x + 1, town_bot_y))) {
		    town_bot_x = town_bot_x + 1;
		}
		if (AIMap.IsValidTile(AIMap.GetTileIndex(town_bot_x, town_bot_y + 1))) {
		    town_bot_y = town_bot_y + 1;
		}
	}
//	AILog.Info("top tile now " + town_top_x + "," + town_top_y + " bottom tile now " + town_bot_x + "," + town_bot_y);
	return [AIMap.GetTileIndex(town_top_x, town_top_y), AIMap.GetTileIndex(town_bot_x, town_bot_y)];
}

////////////////////////////////////

    function estimateTownRectangle(town) {
        local townId = town;
        local townLocation = AITown.GetLocation(town);
        local rectangleIncreaseKoeficient = 1;

        local topCornerTile = AITown.GetLocation(town);
        local bottomCornerTile = AITown.GetLocation(town);

        local isMaxExpanded = false;
        while(!isMaxExpanded) {
            local maxExpandedCounter = 0;
            for(local i = 0; i < 4; ++i) {
                switch(i) {
                    case 0:
                        local offsetTile = Utils.getOffsetTile(topCornerTile, (-1) * rectangleIncreaseKoeficient, 0);

                        if(offsetTile == AIMap.TILE_INVALID) {
                            ++maxExpandedCounter;
                            continue;
                        }

                        if(AITown.IsWithinTownInfluence(town, offsetTile)) {
                            topCornerTile = offsetTile;
                        }
//                        else if(expandRectangle(town, topCornerTile, bottomCornerTile, "NE")) {
//                            topCornerTile = Utils.getOffsetTile(topCornerTile, (-1) * rectangleIncreaseKoeficient, 0);
//                        }
                        else {
                            ++maxExpandedCounter;
                            continue;
                        }
                        break;

                    case 1:
                        local offsetTile = Utils.getOffsetTile(bottomCornerTile, 0, rectangleIncreaseKoeficient);

                        if(offsetTile == AIMap.TILE_INVALID) {
                            ++maxExpandedCounter;
                            continue;
                        }

                        if(AITown.IsWithinTownInfluence(town, offsetTile)) {
                            bottomCornerTile = offsetTile;
                        }
//                        else if(expandRectangle(town, topCornerTile, bottomCornerTile, "SE")) {
//                            bottomCornerTile = Utils.getOffsetTile(bottomCornerTile, 0, rectangleIncreaseKoeficient);
//                        }
                        else {
                            ++maxExpandedCounter;
                            continue;
                        }
                        break;

                    case 2:
                        local offsetTile = Utils.getOffsetTile(bottomCornerTile, rectangleIncreaseKoeficient, 0);

                        if(offsetTile == AIMap.TILE_INVALID) {
                            ++maxExpandedCounter;
                            continue;
                        }

                        if(AITown.IsWithinTownInfluence(town, offsetTile)) {
                            bottomCornerTile = offsetTile;
                        }
//                        else if(expandRectangle(town, topCornerTile, bottomCornerTile, "SW")) {
//                            bottomCornerTile = Utils.getOffsetTile(bottomCornerTile, rectangleIncreaseKoeficient, 0);
//                        }
                        else {
                            ++maxExpandedCounter;
                            continue;
                        }
                        break;

                    case 3:
                        local offsetTile = Utils.getOffsetTile(topCornerTile, 0, (-1) * rectangleIncreaseKoeficient);

                        if(offsetTile == AIMap.TILE_INVALID) {
                            ++maxExpandedCounter;
                        }

                        if(AITown.IsWithinTownInfluence(town, offsetTile)) {
                            topCornerTile = offsetTile;
                        }
//                        else if(expandRectangle(town, topCornerTile, bottomCornerTile, "NW")) {
//                            topCornerTile = Utils.getOffsetTile(topCornerTile, 0, (-1) * rectangleIncreaseKoeficient);
//                        }
                        else {
                            ++maxExpandedCounter;
                        }
                        break;

                    default:
                        break;
                }
            }

            if(maxExpandedCounter == 4) {
                isMaxExpanded = true;
            }
        }

        return [topCornerTile, bottomCornerTile];
    }