2 files changed, 105 insertions, 6 deletions

diff --git a/src/main/kotlin/thedarkcolour/kotlinforforge/forge/Forge.kt b/src/main/kotlin/thedarkcolour/kotlinforforge/forge/Forge.kt
index 37cc207..01f9e90 100644
--- a/src/main/kotlin/thedarkcolour/kotlinforforge/forge/Forge.kt
+++ b/src/main/kotlin/thedarkcolour/kotlinforforge/forge/Forge.kt
@@ -18,6 +18,7 @@ import thedarkcolour.kotlinforforge.eventbus.KotlinEventBusWrapper
 import java.util.*
 import java.util.function.Consumer
 import java.util.function.Predicate
+import java.util.function.Supplier
 import kotlin.collections.HashMap
 import kotlin.properties.ReadOnlyProperty
 import kotlin.reflect.KProperty
@@ -49,7 +50,7 @@ public val FORGE_BUS: KotlinEventBusWrapper = KotlinEventBusWrapper(MinecraftFor
  *
  * Examples:
  *   @see net.minecraftforge.fml.event.lifecycle.InterModProcessEvent
- *   @see net.minecraftforge.event.AttachCapabilitiesEvent
+ *   @see net.minecraftforge.fml.event.lifecycle.FMLClientSetupEvent
  *   @see net.minecraftforge.event.RegistryEvent
  */
 public val MOD_BUS: KotlinEventBus
@@ -158,19 +159,26 @@ public fun <T> sidedDelegate(clientValue: () -> T, serverValue: () -> T): ReadOn
 /** @since 1.2.2
  * Creates a new [ObjectHolderDelegate] with the specified [registryName].
  *
- * This delegate serves as an alternative to using the
- * `@ObjectHolder` annotation, making it easier to use in Kotlin.
+ * Provides ObjectHolders as property delegates instead of magic annotations.
  */
 public inline fun <reified T : IForgeRegistryEntry<in T>> objectHolder(registryName: ResourceLocation): ReadOnlyProperty<Any?, T> {
     return ObjectHolderDelegate(registryName, ObjectHolderDelegate.getRegistry(T::class.java))
 }
 
 /** @since 1.2.2
+ * Creates a new with the specified [namespace] and [registryName].
+ *
+ * Provides ObjectHolders as property delegates instead of magic annotations.
+ */
+public inline fun <reified T : IForgeRegistryEntry<in T>> objectHolder(namespace: String, registryName: String): ReadOnlyProperty<Any?, T> {
+    return ObjectHolderDelegate(ResourceLocation(namespace, registryName), ObjectHolderDelegate.getRegistry(T::class.java))
+}
+
+/** @since 1.2.2
  * Creates a new [ObjectHolderDelegate].
  * This overload uses a string instead of a ResourceLocation.
  *
- * This delegate serves as an alternative to using the
- * `@ObjectHolder` annotation, making it easier to use in Kotlin.
+ * Provides ObjectHolders as property delegates instead of magic annotations.
  */
 public inline fun <reified T : IForgeRegistryEntry<in T>> objectHolder(registryName: String): ReadOnlyProperty<Any?, T> {
     return ObjectHolderDelegate(
@@ -222,6 +230,9 @@ private class SidedDelegate<T>(private val clientValue: () -> T, private val ser
  * This class has proper implementations of
  * [copy], [hashCode], [equals], and [toString].
  *
+ *  @since 1.4.0
+ * [ObjectHolderDelegate] can now be used with the [KDeferredRegister].
+ *
  * @param T the type of object this delegates to
  * @property registryName the registry name of the object this delegate references
  * @property registry the registry the object of this delegate is in
@@ -230,7 +241,7 @@ private class SidedDelegate<T>(private val clientValue: () -> T, private val ser
 public data class ObjectHolderDelegate<T : IForgeRegistryEntry<in T>>(
         private val registryName: ResourceLocation,
         private val registry: IForgeRegistry<*>,
-) : ReadOnlyProperty<Any?, T>, Consumer<Predicate<ResourceLocation>> {
+) : ReadOnlyProperty<Any?, T>, Consumer<Predicate<ResourceLocation>>, Supplier<T> {
     /**
      * Should be initialized by [accept]. If you don't register
      * a value for [registryName] during the appropriate registry event
@@ -242,6 +253,10 @@ public data class ObjectHolderDelegate<T : IForgeRegistryEntry<in T>>(
         ObjectHolderRegistry.addHandler(this)
     }
 
+    override fun get(): T {
+        return value
+    }
+
     override fun getValue(thisRef: Any?, property: KProperty<*>): T {
         return value
     }
diff --git a/src/main/kotlin/thedarkcolour/kotlinforforge/forge/KDeferredRegister.kt b/src/main/kotlin/thedarkcolour/kotlinforforge/forge/KDeferredRegister.kt
new file mode 100644
index 0000000..f556d0f
--- /dev/null
+++ b/src/main/kotlin/thedarkcolour/kotlinforforge/forge/KDeferredRegister.kt
@@ -0,0 +1,84 @@
+package thedarkcolour.kotlinforforge.forge
+
+import net.minecraft.util.ResourceLocation
+import net.minecraftforge.event.RegistryEvent
+import net.minecraftforge.eventbus.api.IEventBus
+import net.minecraftforge.fml.RegistryObject
+import net.minecraftforge.registries.DeferredRegister
+import net.minecraftforge.registries.IForgeRegistry
+import net.minecraftforge.registries.IForgeRegistryEntry
+import net.minecraftforge.registries.RegistryManager
+import thedarkcolour.kotlinforforge.eventbus.KotlinEventBus
+import kotlin.properties.ReadOnlyProperty
+
+/**
+ * Alternative version of [DeferredRegister] that creates
+ * [ObjectHolderDelegate] instances instead of [RegistryObject].
+ */
+public class KDeferredRegister<V : IForgeRegistryEntry<V>>(
+    public val registry: IForgeRegistry<V>,
+    public val modid: String,
+) {
+    /**
+     * A map of all registry objects and their value suppliers.
+     */
+    private val entries = HashMap<ObjectHolderDelegate<out V>, () -> V>()
+
+    /**
+     * Alternative constructor that uses a class instead of a registry.
+     */
+    public constructor(registryClass: Class<V>, modid: String) : this(RegistryManager.ACTIVE.getRegistry(registryClass), modid)
+
+    /**
+     * Registers this deferred register to the `KotlinEventBus`.
+     */
+    public fun register(bus: KotlinEventBus) {
+        bus.addGenericListener(registry.registrySuperType, ::addEntries)
+    }
+
+    /**
+     * Registers this deferred register to the `IEventBus`.
+     */
+    @Deprecated("Use a KotlinEventBus. Forge's EventBus does not support function references for event listeners.")
+    public fun register(bus: IEventBus) {
+        // function references are not supported by Forge's eventbus
+        bus.addGenericListener(registry.registrySuperType) { event: RegistryEvent.Register<V> ->
+            addEntries(event)
+        }
+    }
+
+    /**
+     * Adds a registry object to this deferred registry.
+     *
+     * @param name the path of the new registry object's registry name with namespace [modid]
+     * @param supplier the function to initialize the value of the new registry object with and
+     *                 to reset the value when forge adds reloadable registries.
+     *
+     * @return A new [ObjectHolderDelegate] with the given registry name and value
+     */
+    public fun <T : V> register(name: String, supplier: () -> T): ReadOnlyProperty<Any?, T> {
+        val key = ResourceLocation(modid, name)
+        val a = ObjectHolderDelegate<T>(key, registry)
+
+        entries[a] = { supplier().setRegistryName(key) }
+
+        return a
+    }
+
+    public fun getEntries(): Set<ObjectHolderDelegate<out V>> {
+        return entries.keys
+    }
+
+    /**
+     * Adds all entries in this registry to the corresponding game registries.
+     */
+    private fun addEntries(event: RegistryEvent.Register<V>) {
+        val registry = event.registry
+
+        for ((objectHolder, supplier) in entries) {
+            registry.register(supplier())
+            // pass true to always update the entry
+            objectHolder.accept { true }
+        }
+    }
+}
\ No newline at end of file