minecraft-src/net/minecraft/network/chat/ComponentSerialization.java

package net.minecraft.network.chat;

import com.google.gson.JsonElement;
import com.mojang.datafixers.util.Either;
import com.mojang.datafixers.util.Pair;
import com.mojang.serialization.Codec;
import com.mojang.serialization.DataResult;
import com.mojang.serialization.DynamicOps;
import com.mojang.serialization.JsonOps;
import com.mojang.serialization.MapCodec;
import com.mojang.serialization.MapDecoder;
import com.mojang.serialization.MapEncoder;
import com.mojang.serialization.MapLike;
import com.mojang.serialization.RecordBuilder;
import com.mojang.serialization.codecs.RecordCodecBuilder;
import io.netty.buffer.ByteBuf;
import java.util.List;
import java.util.Optional;
import java.util.function.Function;
import java.util.stream.Stream;
import net.minecraft.network.RegistryFriendlyByteBuf;
import net.minecraft.network.chat.contents.KeybindContents;
import net.minecraft.network.chat.contents.NbtContents;
import net.minecraft.network.chat.contents.PlainTextContents;
import net.minecraft.network.chat.contents.ScoreContents;
import net.minecraft.network.chat.contents.SelectorContents;
import net.minecraft.network.chat.contents.TranslatableContents;
import net.minecraft.network.codec.ByteBufCodecs;
import net.minecraft.network.codec.StreamCodec;
import net.minecraft.resources.RegistryOps;
import net.minecraft.util.ExtraCodecs;
import net.minecraft.util.GsonHelper;
import net.minecraft.util.StringRepresentable;

public class ComponentSerialization {
	public static final Codec<Component> CODEC = Codec.recursive("Component", ComponentSerialization::createCodec);
	public static final StreamCodec<RegistryFriendlyByteBuf, Component> STREAM_CODEC = ByteBufCodecs.fromCodecWithRegistries(CODEC);
	public static final StreamCodec<RegistryFriendlyByteBuf, Optional<Component>> OPTIONAL_STREAM_CODEC = STREAM_CODEC.apply(ByteBufCodecs::optional);
	public static final StreamCodec<RegistryFriendlyByteBuf, Component> TRUSTED_STREAM_CODEC = ByteBufCodecs.fromCodecWithRegistriesTrusted(CODEC);
	public static final StreamCodec<RegistryFriendlyByteBuf, Optional<Component>> TRUSTED_OPTIONAL_STREAM_CODEC = TRUSTED_STREAM_CODEC.apply(
		ByteBufCodecs::optional
	);
	public static final StreamCodec<ByteBuf, Component> TRUSTED_CONTEXT_FREE_STREAM_CODEC = ByteBufCodecs.fromCodecTrusted(CODEC);

	public static Codec<Component> flatRestrictedCodec(int maxSize) {
		return new Codec<Component>() {
			@Override
			public <T> DataResult<Pair<Component, T>> decode(DynamicOps<T> dynamicOps, T object) {
				return ComponentSerialization.CODEC
					.decode(dynamicOps, object)
					.flatMap(
						pair -> this.isTooLarge(dynamicOps, (Component)pair.getFirst())
							? DataResult.error(() -> "Component was too large: greater than max size " + maxSize)
							: DataResult.success(pair)
					);
			}

			public <T> DataResult<T> encode(Component input, DynamicOps<T> ops, T value) {
				return ComponentSerialization.CODEC.encodeStart(ops, input);
			}

			private <T> boolean isTooLarge(DynamicOps<T> ops, Component component) {
				DataResult<JsonElement> dataResult = ComponentSerialization.CODEC.encodeStart(asJsonOps(ops), component);
				return dataResult.isSuccess() && GsonHelper.encodesLongerThan(dataResult.getOrThrow(), maxSize);
			}

			private static <T> DynamicOps<JsonElement> asJsonOps(DynamicOps<T> ops) {
				return (DynamicOps<JsonElement>)(ops instanceof RegistryOps<T> registryOps ? registryOps.withParent(JsonOps.INSTANCE) : JsonOps.INSTANCE);
			}
		};
	}

	private static MutableComponent createFromList(List<Component> components) {
		MutableComponent mutableComponent = ((Component)components.get(0)).copy();

		for (int i = 1; i < components.size(); i++) {
			mutableComponent.append((Component)components.get(i));
		}

		return mutableComponent;
	}

	public static <T extends StringRepresentable, E> MapCodec<E> createLegacyComponentMatcher(
		T[] types, Function<T, MapCodec<? extends E>> codecGetter, Function<E, T> typeGetter, String typeFieldName
	) {
		MapCodec<E> mapCodec = new ComponentSerialization.FuzzyCodec(
			Stream.of(types).map(codecGetter).toList(), object -> (MapEncoder)codecGetter.apply((StringRepresentable)typeGetter.apply(object))
		);
		Codec<T> codec = StringRepresentable.fromValues(() -> types);
		MapCodec<E> mapCodec2 = codec.dispatchMap(typeFieldName, typeGetter, codecGetter);
		MapCodec<E> mapCodec3 = new ComponentSerialization.StrictEither<>(typeFieldName, mapCodec2, mapCodec);
		return ExtraCodecs.orCompressed(mapCodec3, mapCodec2);
	}

	private static Codec<Component> createCodec(Codec<Component> codec) {
		ComponentContents.Type<?>[] types = new ComponentContents.Type[]{
			PlainTextContents.TYPE, TranslatableContents.TYPE, KeybindContents.TYPE, ScoreContents.TYPE, SelectorContents.TYPE, NbtContents.TYPE
		};
		MapCodec<ComponentContents> mapCodec = createLegacyComponentMatcher(types, ComponentContents.Type::codec, ComponentContents::type, "type");
		Codec<Component> codec2 = RecordCodecBuilder.create(
			instance -> instance.group(
					mapCodec.forGetter(Component::getContents),
					ExtraCodecs.nonEmptyList(codec.listOf()).optionalFieldOf("extra", List.of()).forGetter(Component::getSiblings),
					Style.Serializer.MAP_CODEC.forGetter(Component::getStyle)
				)
				.apply(instance, MutableComponent::new)
		);
		return Codec.either(Codec.either(Codec.STRING, ExtraCodecs.nonEmptyList(codec.listOf())), codec2)
			.xmap(either -> either.map(eitherx -> eitherx.map(Component::literal, ComponentSerialization::createFromList), component -> component), component -> {
				String string = component.tryCollapseToString();
				return string != null ? Either.left(Either.left(string)) : Either.right(component);
			});
	}

	static class FuzzyCodec<T> extends MapCodec<T> {
		private final List<MapCodec<? extends T>> codecs;
		private final Function<T, MapEncoder<? extends T>> encoderGetter;

		public FuzzyCodec(List<MapCodec<? extends T>> codecs, Function<T, MapEncoder<? extends T>> encoderGetter) {
			this.codecs = codecs;
			this.encoderGetter = encoderGetter;
		}

		@Override
		public <S> DataResult<T> decode(DynamicOps<S> dynamicOps, MapLike<S> mapLike) {
			for (MapDecoder<? extends T> mapDecoder : this.codecs) {
				DataResult<? extends T> dataResult = mapDecoder.decode(dynamicOps, mapLike);
				if (dataResult.result().isPresent()) {
					return (DataResult<T>)dataResult;
				}
			}

			return DataResult.error(() -> "No matching codec found");
		}

		@Override
		public <S> RecordBuilder<S> encode(T object, DynamicOps<S> dynamicOps, RecordBuilder<S> recordBuilder) {
			MapEncoder<T> mapEncoder = (MapEncoder<T>)this.encoderGetter.apply(object);
			return mapEncoder.encode(object, dynamicOps, recordBuilder);
		}

		@Override
		public <S> Stream<S> keys(DynamicOps<S> dynamicOps) {
			return this.codecs.stream().flatMap(mapCodec -> mapCodec.keys(dynamicOps)).distinct();
		}

		public String toString() {
			return "FuzzyCodec[" + this.codecs + "]";
		}
	}

	static class StrictEither<T> extends MapCodec<T> {
		private final String typeFieldName;
		private final MapCodec<T> typed;
		private final MapCodec<T> fuzzy;

		public StrictEither(String typeFieldName, MapCodec<T> typed, MapCodec<T> fuzzy) {
			this.typeFieldName = typeFieldName;
			this.typed = typed;
			this.fuzzy = fuzzy;
		}

		@Override
		public <O> DataResult<T> decode(DynamicOps<O> dynamicOps, MapLike<O> mapLike) {
			return mapLike.get(this.typeFieldName) != null ? this.typed.decode(dynamicOps, mapLike) : this.fuzzy.decode(dynamicOps, mapLike);
		}

		@Override
		public <O> RecordBuilder<O> encode(T object, DynamicOps<O> dynamicOps, RecordBuilder<O> recordBuilder) {
			return this.fuzzy.encode(object, dynamicOps, recordBuilder);
		}

		@Override
		public <T1> Stream<T1> keys(DynamicOps<T1> dynamicOps) {
			return Stream.concat(this.typed.keys(dynamicOps), this.fuzzy.keys(dynamicOps)).distinct();
		}
	}
}