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

import com.google.common.collect.Lists;
import com.mojang.serialization.MapCodec;
import java.util.List;
import java.util.Optional;
import net.minecraft.core.BlockPos;
import net.minecraft.util.RandomSource;
import net.minecraft.world.level.ChunkPos;
import net.minecraft.world.level.StructureManager;
import net.minecraft.world.level.WorldGenLevel;
import net.minecraft.world.level.block.Blocks;
import net.minecraft.world.level.block.Rotation;
import net.minecraft.world.level.chunk.ChunkGenerator;
import net.minecraft.world.level.levelgen.structure.BoundingBox;
import net.minecraft.world.level.levelgen.structure.Structure;
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 WoodlandMansionStructure extends Structure {
	public static final MapCodec<WoodlandMansionStructure> CODEC = simpleCodec(WoodlandMansionStructure::new);

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

	@Override
	public Optional<Structure.GenerationStub> findGenerationPoint(final Structure.GenerationContext context) {
		Rotation rotation = Rotation.getRandom(context.random());
		BlockPos startPos = this.getLowestYIn5by5BoxOffset7Blocks(context, rotation);
		return startPos.getY() < 60
			? Optional.empty()
			: Optional.of(new Structure.GenerationStub(startPos, builder -> this.generatePieces(builder, context, startPos, rotation)));
	}

	private void generatePieces(final StructurePiecesBuilder builder, final Structure.GenerationContext context, final BlockPos startPos, final Rotation rotation) {
		List<WoodlandMansionPieces.WoodlandMansionPiece> wmPieces = Lists.<WoodlandMansionPieces.WoodlandMansionPiece>newLinkedList();
		WoodlandMansionPieces.generateMansion(context.structureTemplateManager(), startPos, rotation, wmPieces, context.random());
		wmPieces.forEach(builder::addPiece);
	}

	@Override
	public void afterPlace(
		final WorldGenLevel level,
		final StructureManager structureManager,
		final ChunkGenerator generator,
		final RandomSource random,
		final BoundingBox chunkBB,
		final ChunkPos chunkPos,
		final PiecesContainer pieces
	) {
		BlockPos.MutableBlockPos pos = new BlockPos.MutableBlockPos();
		int minY = level.getMinY();
		BoundingBox boundingBox = pieces.calculateBoundingBox();
		int yStart = boundingBox.minY();

		for (int x = chunkBB.minX(); x <= chunkBB.maxX(); x++) {
			for (int z = chunkBB.minZ(); z <= chunkBB.maxZ(); z++) {
				pos.set(x, yStart, z);
				if (!level.isEmptyBlock(pos) && boundingBox.isInside(pos) && pieces.isInsidePiece(pos)) {
					for (int y = yStart - 1; y > minY; y--) {
						pos.setY(y);
						if (!level.isEmptyBlock(pos) && !level.getBlockState(pos).liquid()) {
							break;
						}

						level.setBlock(pos, Blocks.COBBLESTONE.defaultBlockState(), 2);
					}
				}
			}
		}
	}

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