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

import com.mojang.serialization.Codec;
import com.mojang.serialization.MapCodec;
import com.mojang.serialization.codecs.RecordCodecBuilder;
import java.util.Optional;
import net.minecraft.core.BlockPos;
import net.minecraft.core.HolderSet;
import net.minecraft.core.RegistryCodecs;
import net.minecraft.core.registries.Registries;
import net.minecraft.util.RandomSource;
import net.minecraft.world.level.LevelReader;
import net.minecraft.world.level.block.Block;
import org.jspecify.annotations.Nullable;

public class BlockRotProcessor implements StructureProcessor {
	public static final MapCodec<BlockRotProcessor> MAP_CODEC = RecordCodecBuilder.mapCodec(
		i -> i.group(
				RegistryCodecs.homogeneousList(Registries.BLOCK).optionalFieldOf("rottable_blocks").forGetter(t -> t.rottableBlocks),
				Codec.floatRange(0.0F, 1.0F).fieldOf("integrity").forGetter(t -> t.integrity)
			)
			.apply(i, BlockRotProcessor::new)
	);
	private final Optional<HolderSet<Block>> rottableBlocks;
	private final float integrity;

	public BlockRotProcessor(final HolderSet<Block> tag, final float integrity) {
		this(Optional.of(tag), integrity);
	}

	public BlockRotProcessor(final float integrity) {
		this(Optional.empty(), integrity);
	}

	private BlockRotProcessor(final Optional<HolderSet<Block>> blockTagKey, final float integrity) {
		this.integrity = integrity;
		this.rottableBlocks = blockTagKey;
	}

	@Nullable
	@Override
	public StructureTemplate.StructureBlockInfo processBlock(
		final LevelReader level,
		final BlockPos targetPosition,
		final BlockPos referencePos,
		final BlockPos templateRelativePos,
		final StructureTemplate.StructureBlockInfo processedBlockInfo,
		final StructurePlaceSettings settings
	) {
		RandomSource random = settings.getRandom(processedBlockInfo.pos());
		return (!this.rottableBlocks.isPresent() || processedBlockInfo.state().is((HolderSet<Block>)this.rottableBlocks.get()))
				&& !(random.nextFloat() <= this.integrity)
			? null
			: processedBlockInfo;
	}

	@Override
	public MapCodec<BlockRotProcessor> codec() {
		return MAP_CODEC;
	}
}