package net.minecraft.core;

import java.util.Optional;
import net.minecraft.core.Holder.Reference;
import net.minecraft.core.HolderSet.Named;
import net.minecraft.resources.ResourceKey;
import net.minecraft.tags.TagKey;

public interface HolderGetter<T> {
	Optional<Reference<T>> get(ResourceKey<T> resourceKey);

	default Reference<T> getOrThrow(ResourceKey<T> resourceKey) {
		return (Reference<T>)this.get(resourceKey).orElseThrow(() -> new IllegalStateException("Missing element " + resourceKey));
	}

	Optional<Named<T>> get(TagKey<T> tagKey);

	default Named<T> getOrThrow(TagKey<T> tagKey) {
		return (Named<T>)this.get(tagKey).orElseThrow(() -> new IllegalStateException("Missing tag " + tagKey));
	}

	public interface Provider {
		<T> Optional<? extends HolderGetter<T>> lookup(ResourceKey<? extends Registry<? extends T>> registryKey);

		default <T> HolderGetter<T> lookupOrThrow(ResourceKey<? extends Registry<? extends T>> registryKey) {
			return (HolderGetter<T>)this.lookup(registryKey).orElseThrow(() -> new IllegalStateException("Registry " + registryKey.location() + " not found"));
		}

		default <T> Optional<Reference<T>> get(ResourceKey<T> key) {
			return this.lookup(key.registryKey()).flatMap(holderGetter -> holderGetter.get(key));
		}

		default <T> Reference<T> getOrThrow(ResourceKey<T> key) {
			return (Reference<T>)this.lookup(key.registryKey())
				.flatMap(holderGetter -> holderGetter.get(key))
				.orElseThrow(() -> new IllegalStateException("Missing element " + key));
		}
	}
}