(svn r17591) -Add [NoAI] [FS#3212]: AIAirport::IsAirportInformationAvailable. Also update several preconditions so it's now possible to get information on airports types that can no longer be build (small airport after 1960)

3 files changed, 41 insertions, 19 deletions

diff --git a/src/ai/api/ai_airport.cpp b/src/ai/api/ai_airport.cpp
index 3ddb4666d..d3a5f90b6 100644
--- a/src/ai/api/ai_airport.cpp
+++ b/src/ai/api/ai_airport.cpp
@@ -19,7 +19,12 @@
 
 /* static */ bool AIAirport::IsValidAirportType(AirportType type)
 {
-	return type >= 0 && type < (AirportType)NUM_AIRPORTS && ::GetAirport(type)->IsAvailable();
+	return IsAirportInformationAvailable(type) && ::GetAirport(type)->IsAvailable();
+}
+
+/* static */ bool AIAirport::IsAirportInformationAvailable(AirportType type)
+{
+	return type >= 0 && type < (AirportType)NUM_AIRPORTS;
 }
 
 /* static */ Money AIAirport::GetPrice(AirportType type)
@@ -46,21 +51,21 @@
 
 /* static */ int32 AIAirport::GetAirportWidth(AirportType type)
 {
-	if (!IsValidAirportType(type)) return -1;
+	if (!IsAirportInformationAvailable(type)) return -1;
 
 	return ::GetAirport(type)->size_x;
 }
 
 /* static */ int32 AIAirport::GetAirportHeight(AirportType type)
 {
-	if (!IsValidAirportType(type)) return -1;
+	if (!IsAirportInformationAvailable(type)) return -1;
 
 	return ::GetAirport(type)->size_y;
 }
 
 /* static */ int32 AIAirport::GetAirportCoverageRadius(AirportType type)
 {
-	if (!IsValidAirportType(type)) return -1;
+	if (!IsAirportInformationAvailable(type)) return -1;
 
 	return _settings_game.station.modified_catchment ? ::GetAirport(type)->catchment : (uint)CA_UNMODIFIED;
 }
@@ -143,7 +148,7 @@
 	extern Town *AirportGetNearestTown(const AirportFTAClass *afc, TileIndex airport_tile);
 
 	if (!::IsValidTile(tile)) return INVALID_TOWN;
-	if (!IsValidAirportType(type)) return INVALID_TOWN;
+	if (!IsAirportInformationAvailable(type)) return INVALID_TOWN;
 
 	return AirportGetNearestTown(GetAirport(type), tile)->index;
 }
diff --git a/src/ai/api/ai_airport.hpp b/src/ai/api/ai_airport.hpp
index 344cec64a..f0c52bc45 100644
--- a/src/ai/api/ai_airport.hpp
+++ b/src/ai/api/ai_airport.hpp
@@ -57,12 +57,24 @@ public:
 	 * Checks whether the given AirportType is valid and available.
 	 * @param type The AirportType to check.
 	 * @return True if and only if the AirportType is valid and available.
+	 * @post return value == true -> IsAirportInformationAvailable returns true.
 	 */
 	static bool IsValidAirportType(AirportType type);
 
 	/**
+	 * Can you get information on this airport type? As opposed to
+	 * IsValidAirportType this will return also return true when
+	 * an airport type is no longer buildable.
+	 * @param type The AirportType to check.
+	 * @return True if and only if the AirportType is valid.
+	 * @post return value == false -> IsValidAirportType returns false.
+	 */
+	static bool IsAirportInformationAvailable(AirportType type);
+
+	/**
 	 * Get the cost to build this AirportType.
 	 * @param type The AirportType to check.
+	 * @pre AirportAvailable(type).
 	 * @return The cost of building this AirportType.
 	 */
 	static Money GetPrice(AirportType type);
@@ -86,6 +98,7 @@ public:
 	/**
 	 * Get the width of this type of airport.
 	 * @param type The type of airport.
+	 * @pre IsAirportInformationAvailable(type).
 	 * @return The width in tiles.
 	 */
 	static int32 GetAirportWidth(AirportType type);
@@ -93,6 +106,7 @@ public:
 	/**
 	 * Get the height of this type of airport.
 	 * @param type The type of airport.
+	 * @pre IsAirportInformationAvailable(type).
 	 * @return The height in tiles.
 	 */
 	static int32 GetAirportHeight(AirportType type);
@@ -100,6 +114,7 @@ public:
 	/**
 	 * Get the coverage radius of this type of airport.
 	 * @param type The type of airport.
+	 * @pre IsAirportInformationAvailable(type).
 	 * @return The radius in tiles.
 	 */
 	static int32 GetAirportCoverageRadius(AirportType type);
@@ -174,6 +189,7 @@ public:
 	 *  an airport at some tile.
 	 * @param tile The tile to check.
 	 * @param type The AirportType to check.
+	 * @pre IsAirportInformationAvailable(type).
 	 * @return The TownID of the town closest to the tile.
 	 */
 	static TownID GetNearestTown(TileIndex tile, AirportType type);
diff --git a/src/ai/api/ai_airport.hpp.sq b/src/ai/api/ai_airport.hpp.sq
index a63dee040..dd98768f3 100644
--- a/src/ai/api/ai_airport.hpp.sq
+++ b/src/ai/api/ai_airport.hpp.sq
@@ -46,20 +46,21 @@ void SQAIAirport_Register(Squirrel *engine) {
 	SQAIAirport.DefSQConst(engine, AIAirport::PT_BIG_PLANE,     "PT_BIG_PLANE");
 	SQAIAirport.DefSQConst(engine, AIAirport::PT_INVALID,       "PT_INVALID");
 
-	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::IsValidAirportType,       "IsValidAirportType",       2, ".i");
-	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::GetPrice,                 "GetPrice",                 2, ".i");
-	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::IsHangarTile,             "IsHangarTile",             2, ".i");
-	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::IsAirportTile,            "IsAirportTile",            2, ".i");
-	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::GetAirportWidth,          "GetAirportWidth",          2, ".i");
-	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::GetAirportHeight,         "GetAirportHeight",         2, ".i");
-	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::GetAirportCoverageRadius, "GetAirportCoverageRadius", 2, ".i");
-	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::GetNumHangars,            "GetNumHangars",            2, ".i");
-	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::GetHangarOfAirport,       "GetHangarOfAirport",       2, ".i");
-	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::BuildAirport,             "BuildAirport",             4, ".iii");
-	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::RemoveAirport,            "RemoveAirport",            2, ".i");
-	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::GetAirportType,           "GetAirportType",           2, ".i");
-	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::GetNoiseLevelIncrease,    "GetNoiseLevelIncrease",    3, ".ii");
-	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::GetNearestTown,           "GetNearestTown",           3, ".ii");
+	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::IsValidAirportType,            "IsValidAirportType",            2, ".i");
+	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::IsAirportInformationAvailable, "IsAirportInformationAvailable", 2, ".i");
+	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::GetPrice,                      "GetPrice",                      2, ".i");
+	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::IsHangarTile,                  "IsHangarTile",                  2, ".i");
+	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::IsAirportTile,                 "IsAirportTile",                 2, ".i");
+	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::GetAirportWidth,               "GetAirportWidth",               2, ".i");
+	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::GetAirportHeight,              "GetAirportHeight",              2, ".i");
+	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::GetAirportCoverageRadius,      "GetAirportCoverageRadius",      2, ".i");
+	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::GetNumHangars,                 "GetNumHangars",                 2, ".i");
+	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::GetHangarOfAirport,            "GetHangarOfAirport",            2, ".i");
+	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::BuildAirport,                  "BuildAirport",                  4, ".iii");
+	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::RemoveAirport,                 "RemoveAirport",                 2, ".i");
+	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::GetAirportType,                "GetAirportType",                2, ".i");
+	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::GetNoiseLevelIncrease,         "GetNoiseLevelIncrease",         3, ".ii");
+	SQAIAirport.DefSQStaticMethod(engine, &AIAirport::GetNearestTown,                "GetNearestTown",                3, ".ii");
 
 	SQAIAirport.PostRegister(engine);
 }