New API to hook into level loading

src/main/java/ru/bclib/api/LifeCycleAPI.java

@@ -0,0 +1,121 @@
+package ru.bclib.api;
+
+import net.minecraft.core.Registry;
+import net.minecraft.resources.ResourceKey;
+import net.minecraft.server.MinecraftServer;
+import net.minecraft.server.level.ServerLevel;
+import net.minecraft.server.level.progress.ChunkProgressListener;
+import net.minecraft.world.level.CustomSpawner;
+import net.minecraft.world.level.Level;
+import net.minecraft.world.level.biome.Biome;
+import net.minecraft.world.level.chunk.ChunkGenerator;
+import net.minecraft.world.level.dimension.DimensionType;
+import net.minecraft.world.level.storage.LevelStorageSource;
+import net.minecraft.world.level.storage.LevelStorageSource.LevelStorageAccess;
+import net.minecraft.world.level.storage.ServerLevelData;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.Executor;
+
+/**
+ * provides some lifetime hooks for a Minecraft instance
+ */
+public class LifeCycleAPI {
+	private final static List<LevelLoadBiomesCall> onLoadLevelBiomes = new ArrayList<>(2);
+	private final static List<LevelLoadCall> onLoadLevel = new ArrayList<>(2);
+	
+	/**
+	 * A callback function that is used for each new ServerLevel instance
+	 */
+	public interface LevelLoadBiomesCall {
+		void onLoad(ServerLevel world, long seed, Registry<Biome> registry);
+	}
+	
+	/**
+	 * A callback function that is used for each new ServerLevel instance
+	 */
+	public interface LevelLoadCall {
+		void onLoad(
+			ServerLevel world,
+			MinecraftServer minecraftServer,
+			Executor executor,
+			LevelStorageSource.LevelStorageAccess levelStorageAccess,
+			ServerLevelData serverLevelData,
+			ResourceKey<Level> resourceKey,
+			DimensionType dimensionType,
+			ChunkProgressListener chunkProgressListener,
+			ChunkGenerator chunkGenerator,
+			boolean bl,
+			long l,
+			List<CustomSpawner> list,
+			boolean bl2);
+	}
+	
+	/**
+	 * Register a callback that is called when a new {@code ServerLevel is instantiated}.
+	 * This callback will receive the world seed as well as it's biome registry.
+	 * @param call The calbback Method
+	 */
+	public static void onLevelLoad(LevelLoadBiomesCall call){
+		onLoadLevelBiomes.add(call);
+	}
+	
+	/**
+	 * Register a callback that is called when a new {@code ServerLevel is instantiated}.
+	 * This callbacl will receiv all parameters that were passed to the ServerLevel's constructor
+	 * @param call The calbback Method
+	 */
+	public static void onLevelLoad(LevelLoadCall call){
+		onLoadLevel.add(call);
+	}
+	
+	/**
+	 * For internal use, You should not call this method!
+	 * @param minecraftServer
+	 * @param executor
+	 * @param levelStorageAccess
+	 * @param serverLevelData
+	 * @param resourceKey
+	 * @param dimensionType
+	 * @param chunkProgressListener
+	 * @param chunkGenerator
+	 * @param bl
+	 * @param l
+	 * @param list
+	 * @param bl2
+	 */
+	public static void _onLevelLoad(ServerLevel world,
+							 MinecraftServer minecraftServer,
+							 Executor executor,
+							 LevelStorageSource.LevelStorageAccess levelStorageAccess,
+							 ServerLevelData serverLevelData,
+							 ResourceKey<Level> resourceKey,
+							 DimensionType dimensionType,
+							 ChunkProgressListener chunkProgressListener,
+							 ChunkGenerator chunkGenerator,
+							 boolean bl,
+							 long l,
+							 List<CustomSpawner> list,
+							 boolean bl2){
+		onLoadLevel.forEach(c -> c.onLoad(
+			world,
+			minecraftServer,
+			executor,
+			levelStorageAccess,
+			serverLevelData,
+			resourceKey,
+			dimensionType,
+			chunkProgressListener,
+			chunkGenerator,
+			bl,
+			l,
+			list,
+			bl2)
+		);
+		
+		final long seed = world.getSeed();
+		final Registry<Biome> biomeRegistry = world.registryAccess().registryOrThrow(Registry.BIOME_REGISTRY);
+		onLoadLevelBiomes.forEach(c -> c.onLoad(world, seed, biomeRegistry));
+	}
+}

src/main/java/ru/bclib/mixin/common/ServerLevelMixin.java

@@ -17,6 +17,7 @@ import org.spongepowered.asm.mixin.injection.At;
 import org.spongepowered.asm.mixin.injection.Inject;
 import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
 import ru.bclib.api.BiomeAPI;
+import ru.bclib.api.LifeCycleAPI;
 
 import java.util.List;
 import java.util.concurrent.Executor;
@@ -40,5 +41,8 @@ public abstract class ServerLevelMixin extends Level {
 		}
 		
 		bclib_lastWorld = session.getLevelId();
+		
+		ServerLevel world = ServerLevel.class.cast(this);
+		LifeCycleAPI._onLevelLoad(world, server, workerExecutor, session, properties, registryKey, dimensionType, worldGenerationProgressListener, chunkGenerator, debugWorld, l, list, bl);
 	}
 }