2 files changed, 167 insertions, 3 deletions

diff --git a/src/main/java/com/anthonyhilyard/iceberg/Loader.java b/src/main/java/com/anthonyhilyard/iceberg/Loader.java
index b41595f..b1ff65a 100644
--- a/src/main/java/com/anthonyhilyard/iceberg/Loader.java
+++ b/src/main/java/com/anthonyhilyard/iceberg/Loader.java
@@ -1,8 +1,5 @@
 package com.anthonyhilyard.iceberg;
 
-import com.anthonyhilyard.iceberg.events.CriterionEvent;
-import com.anthonyhilyard.iceberg.events.EntityFluidEvent;
-
 import org.apache.commons.lang3.tuple.Pair;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
diff --git a/src/main/java/com/anthonyhilyard/iceberg/registry/AutoRegistry.java b/src/main/java/com/anthonyhilyard/iceberg/registry/AutoRegistry.java
new file mode 100644
index 0000000..dd7da65
--- /dev/null
+++ b/src/main/java/com/anthonyhilyard/iceberg/registry/AutoRegistry.java
@@ -0,0 +1,167 @@
+package com.anthonyhilyard.iceberg.registry;
+
+import java.lang.reflect.Field;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.function.Consumer;
+import java.util.function.Supplier;
+
+import net.minecraft.entity.Entity;
+import net.minecraft.entity.EntityType;
+import net.minecraft.entity.LivingEntity;
+import net.minecraft.entity.ai.attributes.AttributeModifierMap;
+import net.minecraft.util.ResourceLocation;
+import net.minecraft.util.SoundEvent;
+import net.minecraftforge.event.RegistryEvent;
+import net.minecraftforge.fml.client.registry.IRenderFactory;
+import net.minecraftforge.fml.client.registry.RenderingRegistry;
+import net.minecraftforge.fml.javafmlmod.FMLJavaModLoadingContext;
+import net.minecraftforge.registries.ForgeRegistries;
+import net.minecraftforge.registries.IForgeRegistry;
+import net.minecraftforge.registries.IForgeRegistryEntry;
+import net.minecraftforge.event.entity.EntityAttributeCreationEvent;
+
+/**
+ * Extend this class to have all registerable fields be automatically registered in Forge.  Easy.
+ */
+public abstract class AutoRegistry
+{
+	protected static String MODID = null;
+
+	private static boolean entityCreationRegistered = false;
+
+	private static Map<EntityType<?>, Supplier<AttributeModifierMap.MutableAttribute>> entityAttributes = new HashMap<>();
+
+	public static void init(String ModID)
+	{
+		MODID = ModID;
+	}
+
+	@SuppressWarnings("unchecked")
+	protected AutoRegistry()
+	{
+		try
+		{
+			// Iterate through every built-in Forge registry...
+			for (Field field : ForgeRegistries.class.getDeclaredFields())
+			{
+				Object fieldObj = field.get(null);
+				if (fieldObj instanceof IForgeRegistry)
+				{
+					// Grab the registry's supertype and add a generic listener for registry events.
+					Class<IForgeRegistryEntry<?>> clazz = (Class<IForgeRegistryEntry<?>>)((IForgeRegistry<?>)fieldObj).getRegistrySuperType();
+					FMLJavaModLoadingContext.get().getModEventBus().addGenericListener(clazz, (Consumer<RegistryEvent.Register<? extends IForgeRegistryEntry<?>>>)(e) -> registerAllOfType(clazz, e) );
+				}
+			}
+		}
+		catch (Exception e)
+		{
+			throw new RuntimeException(e);
+		}
+	}
+
+	@SuppressWarnings("unchecked")
+	private final <T extends IForgeRegistryEntry<T>> void registerAllOfType(Class<IForgeRegistryEntry<?>> type, RegistryEvent.Register<T> event)
+	{
+		try
+		{
+			// Loop through all fields we've declared and register them.
+			for (Field field : this.getClass().getDeclaredFields())
+			{
+				// Grab the field and check if it is a Forge registry-compatible type.
+				Object obj = field.get(this);
+				if (type.isAssignableFrom(obj.getClass()))
+				{
+					// If this is an entity type field and we haven't already registered for the entity creation event, do so now.
+					if (obj instanceof EntityType && !entityCreationRegistered)
+					{
+						FMLJavaModLoadingContext.get().getModEventBus().addListener(this::onEntityCreation);
+						entityCreationRegistered = true;
+					}
+
+					// If this field has a registry name, register it now.
+					T entry = (T)obj;
+					if (entry != null && entry.getRegistryName() != null)
+					{
+						event.getRegistry().register(entry);
+					}
+				}
+			}
+		}
+		catch (Exception e)
+		{
+			throw new RuntimeException(e);
+		}
+	}
+
+	protected static <T extends Entity> EntityType<T> registerEntity(String name, EntityType.Builder<T> builder, IRenderFactory<? super T> renderFactory)
+	{
+		return registerEntity(name, builder, renderFactory, null);
+	}
+
+	@SuppressWarnings("unchecked")
+	protected static <T extends Entity> EntityType<T> registerEntity(String name, EntityType.Builder<T> builder, IRenderFactory<? super T> renderFactory, Supplier<AttributeModifierMap.MutableAttribute> attributes)
+	{
+		if (MODID == null)
+		{
+			throw new RuntimeException("AutoRegistry was not initialized with mod id!");
+		}
+
+		// Build the entity type.
+		ResourceLocation resourceLocation = new ResourceLocation(MODID, name);
+		EntityType<T> entityType = (EntityType<T>) builder.build(name).setRegistryName(resourceLocation);
+
+		// Register the rendering handler.
+		RenderingRegistry.registerEntityRenderingHandler(entityType, renderFactory);
+
+		// Store mob attributes if provided.  These will be added in the attribute creation event below.
+		if (attributes != null)
+		{
+			entityAttributes.put(entityType, attributes);
+		}
+
+
+		return entityType;
+	}
+
+	protected static SoundEvent registerSound(String name)
+	{
+		if (MODID == null)
+		{
+			throw new RuntimeException("AutoRegistry was not initialized with mod id!");
+		}
+
+		return new SoundEvent(new ResourceLocation(MODID, name));
+	}
+
+	@SuppressWarnings("unchecked")
+	private void onEntityCreation(EntityAttributeCreationEvent event)
+	{
+		for (Field field : this.getClass().getDeclaredFields())
+		{
+			try
+			{
+				// Grab the field and check if it is a Forge registry-compatible type.
+				Object obj = field.get(this);
+				if (EntityType.class.isAssignableFrom(obj.getClass()) && entityAttributes.containsKey(obj))
+				{
+					EntityType<? extends LivingEntity> entityType = (EntityType<? extends LivingEntity>) obj;
+					if (entityType != null)
+					{
+						event.put(entityType, entityAttributes.get(obj).get().build());
+					}
+				}
+			}
+			catch (ClassCastException e)
+			{
+				// The class cast exception likely just means that we tried to convert an EntityType with generic type
+				// parameter of something other than a LivingEntity subclass.  This is fine, so continue.
+				continue;
+			}
+			catch (IllegalAccessException e)
+			{
+				throw new RuntimeException(e);
+			}
+		}
+	}
+}
\ No newline at end of file