package net.minecraft.util.datafix.fixes;

import com.google.common.collect.Streams;
import com.mojang.datafixers.schemas.Schema;
import com.mojang.serialization.Dynamic;
import java.util.List;
import java.util.Optional;
import java.util.stream.Stream;
import net.minecraft.util.datafix.LegacyComponentDataFixUtils;

public class BlockEntitySignDoubleSidedEditableTextFix extends NamedEntityWriteReadFix {
	public static final List<String> FIELDS_TO_DROP = List.of(
		"Text1", "Text2", "Text3", "Text4", "FilteredText1", "FilteredText2", "FilteredText3", "FilteredText4", "Color", "GlowingText"
	);
	public static final String FILTERED_CORRECT = "_filtered_correct";
	private static final String DEFAULT_COLOR = "black";

	public BlockEntitySignDoubleSidedEditableTextFix(final Schema outputSchema, final String name, final String entityName) {
		super(outputSchema, true, name, References.BLOCK_ENTITY, entityName);
	}

	@Override
	protected <T> Dynamic<T> fix(Dynamic<T> input) {
		input = input.set("front_text", fixFrontTextTag(input))
			.set("back_text", createDefaultText(input))
			.set("is_waxed", input.createBoolean(false))
			.set("_filtered_correct", input.createBoolean(true));

		for (String field : FIELDS_TO_DROP) {
			input = input.remove(field);
		}

		return input;
	}

	private static <T> Dynamic<T> fixFrontTextTag(final Dynamic<T> tag) {
		Dynamic<T> emptyLine = LegacyComponentDataFixUtils.createEmptyComponent(tag.getOps());
		List<Dynamic<T>> lines = getLines(tag, "Text").map(line -> (Dynamic)line.orElse(emptyLine)).toList();
		Dynamic<T> text = tag.emptyMap()
			.set("messages", tag.createList(lines.stream()))
			.set("color", (Dynamic<?>)tag.get("Color").result().orElse(tag.createString("black")))
			.set("has_glowing_text", (Dynamic<?>)tag.get("GlowingText").result().orElse(tag.createBoolean(false)));
		List<Optional<Dynamic<T>>> filteredLines = getLines(tag, "FilteredText").toList();
		if (filteredLines.stream().anyMatch(Optional::isPresent)) {
			text = text.set("filtered_messages", tag.createList(Streams.mapWithIndex(filteredLines.stream(), (line, index) -> {
				Dynamic<T> fallbackLine = (Dynamic<T>)lines.get((int)index);
				return (Dynamic<?>)line.orElse(fallbackLine);
			})));
		}

		return text;
	}

	private static <T> Stream<Optional<Dynamic<T>>> getLines(final Dynamic<T> tag, final String linePrefix) {
		return Stream.of(
			tag.get(linePrefix + "1").result(), tag.get(linePrefix + "2").result(), tag.get(linePrefix + "3").result(), tag.get(linePrefix + "4").result()
		);
	}

	private static <T> Dynamic<T> createDefaultText(final Dynamic<T> tag) {
		return tag.emptyMap().set("messages", createEmptyLines(tag)).set("color", tag.createString("black")).set("has_glowing_text", tag.createBoolean(false));
	}

	private static <T> Dynamic<T> createEmptyLines(final Dynamic<T> tag) {
		Dynamic<T> emptyComponent = LegacyComponentDataFixUtils.createEmptyComponent(tag.getOps());
		return tag.createList(Stream.of(emptyComponent, emptyComponent, emptyComponent, emptyComponent));
	}
}