package net.minecraft.client.renderer.block.dispatch.multipart;

import com.mojang.datafixers.util.Either;
import com.mojang.serialization.Codec;
import com.mojang.serialization.DataResult;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.function.Predicate;
import net.minecraft.util.StringRepresentable;
import net.minecraft.world.level.block.state.StateDefinition;
import net.minecraft.world.level.block.state.StateHolder;

@FunctionalInterface
public interface Condition {
	Codec<Condition> CODEC = Codec.recursive(
		"condition",
		self -> {
			Codec<CombinedCondition> combinerCodec = Codec.simpleMap(
					CombinedCondition.Operation.CODEC, self.listOf(), StringRepresentable.keys(CombinedCondition.Operation.values())
				)
				.codec()
				.comapFlatMap(map -> {
					if (map.size() != 1) {
						return DataResult.error(() -> "Invalid map size for combiner condition, expected exactly one element");
					} else {
						Entry<CombinedCondition.Operation, List<Condition>> entry = (Entry<CombinedCondition.Operation, List<Condition>>)map.entrySet().iterator().next();
						return DataResult.success(new CombinedCondition((CombinedCondition.Operation)entry.getKey(), (List<Condition>)entry.getValue()));
					}
				}, condition -> Map.of(condition.operation(), condition.terms()));
			return Codec.either(combinerCodec, KeyValueCondition.CODEC).flatComapMap(either -> either.map(l -> l, r -> r), condition -> {
				return switch (condition) {
					case CombinedCondition combiner -> DataResult.success(Either.left(combiner));
					case KeyValueCondition keyValue -> DataResult.success(Either.right(keyValue));
					default -> DataResult.error(() -> "Unrecognized condition");
				};
			});
		}
	);

	<O, S extends StateHolder<O, S>> Predicate<S> instantiate(StateDefinition<O, S> definition);
}