package net.minecraft.util.datafix.fixes;

import com.mojang.datafixers.DSL;
import com.mojang.datafixers.DataFix;
import com.mojang.datafixers.TypeRewriteRule;
import com.mojang.datafixers.schemas.Schema;
import com.mojang.datafixers.types.Type;
import com.mojang.serialization.Dynamic;

public class IglooMetadataRemovalFix extends DataFix {
	public IglooMetadataRemovalFix(final Schema outputSchema, final boolean changesType) {
		super(outputSchema, changesType);
	}

	@Override
	protected TypeRewriteRule makeRule() {
		Type<?> type = this.getInputSchema().getType(References.STRUCTURE_FEATURE);
		return this.fixTypeEverywhereTyped("IglooMetadataRemovalFix", type, typed -> typed.update(DSL.remainderFinder(), IglooMetadataRemovalFix::fixTag));
	}

	private static <T> Dynamic<T> fixTag(final Dynamic<T> input) {
		boolean isIglooOnly = (Boolean)input.get("Children").asStreamOpt().map(s -> s.allMatch(IglooMetadataRemovalFix::isIglooPiece)).result().orElse(false);
		return isIglooOnly ? input.set("id", input.createString("Igloo")).remove("Children") : input.update("Children", IglooMetadataRemovalFix::removeIglooPieces);
	}

	private static <T> Dynamic<T> removeIglooPieces(final Dynamic<T> children) {
		return (Dynamic<T>)children.asStreamOpt().map(s -> s.filter(v -> !isIglooPiece(v))).map(children::createList).result().orElse(children);
	}

	private static boolean isIglooPiece(final Dynamic<?> tag) {
		return tag.get("id").asString("").equals("Iglu");
	}
}