package net.minecraft.world.level.levelgen.structure.structures;

import com.mojang.serialization.MapCodec;
import java.util.Objects;
import java.util.Optional;
import net.minecraft.core.Direction;
import net.minecraft.core.Holder;
import net.minecraft.tags.BiomeTags;
import net.minecraft.world.level.ChunkPos;
import net.minecraft.world.level.biome.Biome;
import net.minecraft.world.level.levelgen.Heightmap;
import net.minecraft.world.level.levelgen.LegacyRandomSource;
import net.minecraft.world.level.levelgen.RandomSupport;
import net.minecraft.world.level.levelgen.WorldgenRandom;
import net.minecraft.world.level.levelgen.structure.BoundingBox;
import net.minecraft.world.level.levelgen.structure.Structure;
import net.minecraft.world.level.levelgen.structure.StructurePiece;
import net.minecraft.world.level.levelgen.structure.StructureType;
import net.minecraft.world.level.levelgen.structure.pieces.PiecesContainer;
import net.minecraft.world.level.levelgen.structure.pieces.StructurePiecesBuilder;

public class OceanMonumentStructure extends Structure {
	public static final MapCodec<OceanMonumentStructure> CODEC = simpleCodec(OceanMonumentStructure::new);

	public OceanMonumentStructure(final Structure.StructureSettings settings) {
		super(settings);
	}

	@Override
	public Optional<Structure.GenerationStub> findGenerationPoint(final Structure.GenerationContext context) {
		int offsetX = context.chunkPos().getBlockX(9);
		int offsetZ = context.chunkPos().getBlockZ(9);

		for (Holder<Biome> biome : context.biomeSource()
			.getBiomesWithin(offsetX, context.chunkGenerator().getSeaLevel(), offsetZ, 29, context.randomState().sampler())) {
			if (!biome.is(BiomeTags.REQUIRED_OCEAN_MONUMENT_SURROUNDING)) {
				return Optional.empty();
			}
		}

		return onTopOfChunkCenter(context, Heightmap.Types.OCEAN_FLOOR_WG, builder -> generatePieces(builder, context));
	}

	private static StructurePiece createTopPiece(final ChunkPos chunkPos, final WorldgenRandom random) {
		int west = chunkPos.getMinBlockX() - 29;
		int north = chunkPos.getMinBlockZ() - 29;
		Direction orientation = Direction.Plane.HORIZONTAL.getRandomDirection(random);
		return new OceanMonumentPieces.MonumentBuilding(random, west, north, orientation);
	}

	private static void generatePieces(final StructurePiecesBuilder builder, final Structure.GenerationContext context) {
		builder.addPiece(createTopPiece(context.chunkPos(), context.random()));
	}

	public static PiecesContainer regeneratePiecesAfterLoad(final ChunkPos chunkPos, final long seed, final PiecesContainer savedPieces) {
		if (savedPieces.isEmpty()) {
			return savedPieces;
		} else {
			WorldgenRandom random = new WorldgenRandom(new LegacyRandomSource(RandomSupport.generateUniqueSeed()));
			random.setLargeFeatureSeed(seed, chunkPos.x(), chunkPos.z());
			StructurePiece oldTopPiece = (StructurePiece)savedPieces.pieces().get(0);
			BoundingBox oldBoundingBox = oldTopPiece.getBoundingBox();
			int west = oldBoundingBox.minX();
			int north = oldBoundingBox.minZ();
			Direction defaultOrientation = Direction.Plane.HORIZONTAL.getRandomDirection(random);
			Direction orientation = (Direction)Objects.requireNonNullElse(oldTopPiece.getOrientation(), defaultOrientation);
			StructurePiece topPiece = new OceanMonumentPieces.MonumentBuilding(random, west, north, orientation);
			StructurePiecesBuilder result = new StructurePiecesBuilder();
			result.addPiece(topPiece);
			return result.build();
		}
	}

	@Override
	public StructureType<?> type() {
		return StructureType.OCEAN_MONUMENT;
	}
}