/**
* Generates a metatable containing metafunctions for a given object type using the currently
* registered {@link LuaObjectMeta}s.
*
* <p>This method will only generate one metatable per class type; the mapping of already made
* metatables will not be cleared at any point during runtime. If a metatable had already been
* generated, that metatable is returned.
*
* <p>It is possible for functions within each object meta to override each other when this method
* generates a new metatable.
*
* <p>If there are no suitable meta objects for the provided object or none of the applicable meta
* objects have any metafunctions to register, null is returned.
*
* @param obj the Object to generate a metatable for
* @return the metatable for the given Object
*/
public static LuaTable generateMetatable(Object obj) {
LuaTable copyTable = Lua.METATABLES.get(obj.getClass());
if (copyTable == null && copyTable != Lua.EMPTY_METATABLE) {
LuaTable functable = new LuaTable();
Lua.metas.clear();
Lua.META.values().forEach(Lua.metas::add);
Lua.PMETA.values().forEach(Lua.metas::add);
Lua.metas.forEach(
meta -> {
if (meta.getTargetObjectClass().isInstance(obj) && meta.getMetatable() != null) {
LuaUtil.iterateTable(
meta.getMetatable(),
vargs -> {
functable.set(vargs.arg(1), vargs.arg(2));
});
}
});
Lua.metas.forEach(
meta -> {
meta.postMetaInit(functable);
});
if (LuaUtil.getTableSize(functable) > 0) {
LuaTable metatable = new LuaTable();
// add the object's metatable functions
metatable.set("__index", functable);
// add the stuff we do for every metatable
GLOBAL_METATABLE
.entries()
.forEach(
entry -> {
metatable.set(entry.key, entry.value);
});
Lua.METATABLES.put(obj.getClass(), metatable);
copyTable = metatable;
} else {
Lua.METATABLES.put(obj.getClass(), Lua.EMPTY_METATABLE);
}
}
if (copyTable != null && copyTable != Lua.EMPTY_METATABLE) {
return LuaUtil.copyTable(copyTable, true);
}
return null;
}
static {
metas = new ObjectSet<>();
META = new ObjectMap<>();
PMETA = new ObjectMap<>();
METATABLES = new ObjectMap<>();
GLOBAL_METATABLE = new ObjectMap<>();
EMPTY_METATABLE = new LuaTable();
// Metamethods implementation for all LuaObjectValues.
GLOBAL_METATABLE.put(
LuaValue.EQ.tojstring(),
LuaUtil.asFunction(
vargs -> {
if (vargs.isnil(2)) {
// We'll still get called for nil. Automagically return false for nil.
return LuaValue.valueOf(false);
}
// obj1, us, is guaranteed to be an object value
LuaObjectValue<? super Object> obj1 = (LuaObjectValue<? super Object>) vargs.arg(1);
LuaValue obj2 = vargs.arg(2);
if (obj2 instanceof LuaObjectValue) {
return LuaValue.valueOf(
obj1.getObject() == ((LuaObjectValue<? super Object>) obj2).getObject());
}
return LuaValue.valueOf(false);
}));
loadMeta(LuaAudioDataMeta.class);
loadMeta(LuaAudioMeta.class);
loadMeta(LuaAudioPlayableMeta.class);
loadMeta(LuaColliderMeta.class);
loadMeta(LuaColorMeta.class);
loadMeta(LuaDestructibleMeta.class);
loadMeta(LuaEnvironmentMeta.class);
loadMeta(LuaEventListenerMeta.class);
loadMeta(LuaFontMeta.class);
loadMeta(LuaIdentifiableMeta.class);
loadMeta(LuaInputDataMeta.class);
loadMeta(LuaLayerableMeta.class);
loadMeta(LuaMusicMeta.class);
loadMeta(LuaOverworldControllerMeta.class);
loadMeta(LuaPositionableMeta.class);
loadMeta(LuaPressDataMeta.class);
loadMeta(LuaProcessableMeta.class);
loadMeta(LuaRenderableMeta.class);
loadMeta(LuaSchedulerMeta.class);
loadMeta(LuaSoundDataMeta.class);
loadMeta(LuaSoundMeta.class);
loadMeta(LuaSpriteMeta.class);
loadMeta(LuaSubsystemMeta.class);
loadMeta(LuaTextComponentMeta.class);
loadMeta(LuaTextMeta.class);
loadMeta(LuaTextStyleMeta.class);
loadMeta(LuaTransformMeta.class);
loadMeta(LuaUIComponentMeta.class);
loadMeta(LuaUIControllerMeta.class);
loadMeta(LuaUIObjectMeta.class);
loadMeta(LuaWorldObjectMeta.class);
loadMeta(new LuaWorldRoomMeta(Undertailor.getInstance()));
log.info("Finished loading lua object metadata");
log.info("Primary types list: ");
Lua.PMETA
.values()
.forEach(
meta -> {
log.info(meta.getClass().getSimpleName());
});
}