Resolved FIXME(s) in EntityEvents

src/main/java/twilightforest/command/InfoCommand.java

@@ -14,7 +14,6 @@
 import net.minecraft.resources.Identifier;
 import net.minecraft.server.level.ServerLevel;
 import net.minecraft.util.random.Weighted;
-import net.minecraft.util.random.WeightedList;
 import net.minecraft.world.entity.MobCategory;
 import net.minecraft.world.level.biome.MobSpawnSettings;
 import net.minecraft.world.level.levelgen.structure.BoundingBox;
@@ -26,6 +25,7 @@
 import twilightforest.world.components.structures.start.TFStructureStart;
 import twilightforest.world.components.structures.util.LandmarkStructure;
 
+import java.util.ArrayList;
 import java.util.List;
 import java.util.Optional;
 import java.util.StringJoiner;
@@ -78,11 +78,14 @@ private int run(CommandContext<CommandSourceStack> ctx) {
 			}
 
 			// what is the spawn list
-			WeightedList<MobSpawnSettings.SpawnerData> spawnList = EntityEvents.gatherPotentialSpawns(level.structureManager(), MobCategory.MONSTER, pos);
-			source.sendSuccess(() -> Component.translatable("commands.tffeature.structure.spawn_list").withStyle(ChatFormatting.UNDERLINE), false);
-			if (spawnList != null)
-				for (Weighted<MobSpawnSettings.SpawnerData> entry : spawnList.unwrap())
-					source.sendSuccess(() -> Component.translatable("commands.tffeature.structure.spawn_info", entry.value().type().getDescription().getString(), entry.weight()), false);
+			List<Weighted<MobSpawnSettings.SpawnerData>> spawnList = new ArrayList<>();
+
+			EntityEvents.gatherPotentialSpawns(level.structureManager(), MobCategory.MONSTER, pos, spawnList::add);
+
+			if (!spawnList.isEmpty()) {
+				source.sendSuccess(() -> Component.translatable("commands.tffeature.structure.spawn_list").withStyle(ChatFormatting.UNDERLINE), false);
+				spawnList.forEach(entry -> source.sendSuccess(() -> Component.translatable("commands.tffeature.structure.spawn_info", entry.value().type().getDescription().getString(), entry.weight()), false));
+			}
 		} else {
 			source.sendSuccess(() -> Component.translatable("commands.tffeature.structure.outside").withStyle(ChatFormatting.BOLD, ChatFormatting.RED), false);
 		}

src/main/java/twilightforest/events/EntityEvents.java

@@ -12,7 +12,7 @@
 import net.minecraft.sounds.SoundSource;
 import net.minecraft.tags.DamageTypeTags;
 import net.minecraft.tags.ItemTags;
-import net.minecraft.util.random.WeightedList;
+import net.minecraft.util.random.Weighted;
 import net.minecraft.world.Difficulty;
 import net.minecraft.world.InteractionResult;
 import net.minecraft.world.damagesource.DamageSource;
@@ -62,7 +62,6 @@
 import net.neoforged.neoforge.event.level.LevelEvent;
 import net.neoforged.neoforge.items.ItemHandlerHelper;
 import net.neoforged.neoforge.network.PacketDistributor;
-import org.jetbrains.annotations.Nullable;
 import tamaized.beanification.PostConstruct;
 import twilightforest.TwilightForestMod;
 import twilightforest.advancements.DrinkFromFlaskTrigger;
@@ -88,11 +87,13 @@
 import twilightforest.world.components.structures.SpawnIndexProvider;
 import twilightforest.world.components.structures.finalcastle.FinalCastleBossGazeboComponent;
 import twilightforest.world.components.structures.start.TFStructureStart;
-import twilightforest.world.components.structures.type.HollowHillStructure;
 import twilightforest.world.components.structures.util.ControlledSpawns;
+import twilightforest.world.components.structures.util.ValidatedSpawnLocations;
 
+import java.util.ArrayList;
 import java.util.List;
 import java.util.Optional;
+import java.util.function.Consumer;
 
 @tamaized.beanification.Component
 public class EntityEvents {
@@ -369,45 +370,58 @@ private static int getSpawnListIndexAt(StructureStart start, BlockPos pos) {
 		return highestFoundIndex;
 	}
 
-	@Nullable
-	public static WeightedList<MobSpawnSettings.SpawnerData> gatherPotentialSpawns(StructureManager structureManager, MobCategory classification, BlockPos pos) {
+	public static void gatherPotentialSpawns(StructureManager structureManager, MobCategory classification, BlockPos pos, Consumer<Weighted<MobSpawnSettings.SpawnerData>> consumer) {
 		List<StructureStart> structureStarts = structureManager.startsForStructure(ChunkPos.containing(pos), s -> s instanceof ControlledSpawns);
 
-		// This is wretched FIXME make this method return void instead, make one of parameters the SpawnerData consumer (eg LevelEvent.PotentialSpawns::addSpawnerData or List::add)
 		for (StructureStart start : structureStarts) {
 			if (start.getStructure() instanceof ControlledSpawns landmark) {
 
 				if (!start.isValid())
 					continue;
 
-				if (classification != MobCategory.MONSTER)
-					return landmark.getSpawnableList(classification);
+				if (classification != MobCategory.MONSTER) {
+					landmark.getSpawnableList(classification)
+						.unwrap()
+						.forEach(consumer);
+
+					return;
+				}
 
 				if (start instanceof TFStructureStart s && s.isConquered())
-					return null;
+					return;
 
-				// FIXME Make interface for this method?
-				if (landmark instanceof HollowHillStructure hollowHill && !hollowHill.canSpawnMob(pos, start.getBoundingBox()))
-					return null;
+				if (landmark instanceof ValidatedSpawnLocations validator && !validator.canSpawnMob(pos, start.getBoundingBox()))
+					return;
 
 				final int index = getSpawnListIndexAt(start, pos);
 				if (index < 0)
-					return null;
-				return landmark.getSpawnableMonsterList(index);
+					return;
+
+				landmark.getSpawnableMonsterList(index)
+					.unwrap()
+					.forEach(consumer);
+
+				return;
 			}
 		}
-
-		return null;
 	}
 
 	private void structureSpecialSpawns(LevelEvent.PotentialSpawns event) {
 		if (!(event.getLevel() instanceof ServerLevel serverLevel))
 			return;
 
-		WeightedList<MobSpawnSettings.SpawnerData> potentialStructureSpawns = gatherPotentialSpawns(serverLevel.structureManager(), event.getMobCategory(), event.getPos());
-		if (potentialStructureSpawns != null) {
+		List<Weighted<MobSpawnSettings.SpawnerData>> potentialStructureSpawns = new ArrayList<>();
+
+		gatherPotentialSpawns(
+			serverLevel.structureManager(),
+			event.getMobCategory(),
+			event.getPos(),
+			potentialStructureSpawns::add
+		);
+
+		if (!potentialStructureSpawns.isEmpty()) {
 			List.copyOf(event.getSpawnerDataList()).forEach(event::removeSpawnerData);
-			potentialStructureSpawns.unwrap().forEach(event::addSpawnerData);
+			potentialStructureSpawns.forEach(event::addSpawnerData);
 		}
 	}
 

src/main/java/twilightforest/world/components/structures/type/HollowHillStructure.java

@@ -34,13 +34,14 @@
 import twilightforest.world.components.structures.util.ConfigurableSpawns;
 import twilightforest.world.components.structures.util.ControlledSpawns;
 import twilightforest.world.components.structures.util.LandmarkStructure;
+import twilightforest.world.components.structures.util.ValidatedSpawnLocations;
 
 import java.util.Arrays;
 import java.util.List;
 import java.util.Optional;
 import java.util.stream.Collectors;
 
-public class HollowHillStructure extends LandmarkStructure implements ConfigurableSpawns, CustomDensitySource {
+public class HollowHillStructure extends LandmarkStructure implements ConfigurableSpawns, CustomDensitySource, ValidatedSpawnLocations {
 	public static final MapCodec<HollowHillStructure> CODEC = RecordCodecBuilder.mapCodec(instance -> instance
 		.group(
 			// TODO Clean up findGenerationPoint() first before even thinking about increasing upper limit
@@ -64,6 +65,7 @@ public HollowHillStructure(int size, ControlledSpawningConfig controlledSpawning
 	}
 
 	// "Cuts" the box into a half-dome
+	@Override
 	public boolean canSpawnMob(BlockPos spawnPos, BoundingBox structureStartBox) {
 		float hX = Mth.inverseLerp(spawnPos.getX(), structureStartBox.minX(), structureStartBox.maxX()) * 2 - 1;
 		float hY = Mth.inverseLerp(spawnPos.getY(), structureStartBox.minY(), structureStartBox.maxY());

src/main/java/twilightforest/world/components/structures/util/ValidatedSpawnLocations.java

@@ -0,0 +1,8 @@
+package twilightforest.world.components.structures.util;
+
+import net.minecraft.core.BlockPos;
+import net.minecraft.world.level.levelgen.structure.BoundingBox;
+
+public interface ValidatedSpawnLocations {
+	boolean canSpawnMob(BlockPos pos, BoundingBox structureBounds);
+}