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

import com.mojang.serialization.MapCodec;
import com.mojang.serialization.codecs.RecordCodecBuilder;
import java.util.Optional;
import net.minecraft.core.BlockPos;
import net.minecraft.core.Direction;
import net.minecraft.world.level.EmptyBlockGetter;
import net.minecraft.world.level.NoiseColumn;
import net.minecraft.world.level.block.Blocks;
import net.minecraft.world.level.block.state.BlockState;
import net.minecraft.world.level.levelgen.WorldGenerationContext;
import net.minecraft.world.level.levelgen.WorldgenRandom;
import net.minecraft.world.level.levelgen.heightproviders.HeightProvider;
import net.minecraft.world.level.levelgen.structure.Structure;
import net.minecraft.world.level.levelgen.structure.StructureType;

public class NetherFossilStructure extends Structure {
	public static final MapCodec<NetherFossilStructure> CODEC = RecordCodecBuilder.mapCodec(
		instance -> instance.group(settingsCodec(instance), HeightProvider.CODEC.fieldOf("height").forGetter(netherFossilStructure -> netherFossilStructure.height))
			.apply(instance, NetherFossilStructure::new)
	);
	public final HeightProvider height;

	public NetherFossilStructure(Structure.StructureSettings settings, HeightProvider height) {
		super(settings);
		this.height = height;
	}

	@Override
	public Optional<Structure.GenerationStub> findGenerationPoint(Structure.GenerationContext context) {
		WorldgenRandom worldgenRandom = context.random();
		int i = context.chunkPos().getMinBlockX() + worldgenRandom.nextInt(16);
		int j = context.chunkPos().getMinBlockZ() + worldgenRandom.nextInt(16);
		int k = context.chunkGenerator().getSeaLevel();
		WorldGenerationContext worldGenerationContext = new WorldGenerationContext(context.chunkGenerator(), context.heightAccessor());
		int l = this.height.sample(worldgenRandom, worldGenerationContext);
		NoiseColumn noiseColumn = context.chunkGenerator().getBaseColumn(i, j, context.heightAccessor(), context.randomState());
		BlockPos.MutableBlockPos mutableBlockPos = new BlockPos.MutableBlockPos(i, l, j);

		while (l > k) {
			BlockState blockState = noiseColumn.getBlock(l);
			BlockState blockState2 = noiseColumn.getBlock(--l);
			if (blockState.isAir() && (blockState2.is(Blocks.SOUL_SAND) || blockState2.isFaceSturdy(EmptyBlockGetter.INSTANCE, mutableBlockPos.setY(l), Direction.UP))) {
				break;
			}
		}

		if (l <= k) {
			return Optional.empty();
		} else {
			BlockPos blockPos = new BlockPos(i, l, j);
			return Optional.of(
				new Structure.GenerationStub(
					blockPos, structurePiecesBuilder -> NetherFossilPieces.addPieces(context.structureTemplateManager(), structurePiecesBuilder, worldgenRandom, blockPos)
				)
			);
		}
	}

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