package net.minecraft.world.level.levelgen.feature;

import com.mojang.logging.LogUtils;
import com.mojang.serialization.Codec;
import java.util.function.Predicate;
import net.minecraft.Util;
import net.minecraft.core.BlockPos;
import net.minecraft.core.Direction;
import net.minecraft.tags.BlockTags;
import net.minecraft.util.RandomSource;
import net.minecraft.world.RandomizableContainer;
import net.minecraft.world.entity.EntityType;
import net.minecraft.world.level.WorldGenLevel;
import net.minecraft.world.level.block.Blocks;
import net.minecraft.world.level.block.entity.SpawnerBlockEntity;
import net.minecraft.world.level.block.state.BlockState;
import net.minecraft.world.level.levelgen.feature.configurations.NoneFeatureConfiguration;
import net.minecraft.world.level.levelgen.structure.StructurePiece;
import net.minecraft.world.level.storage.loot.BuiltInLootTables;
import org.slf4j.Logger;

public class MonsterRoomFeature extends Feature<NoneFeatureConfiguration> {
	private static final Logger LOGGER = LogUtils.getLogger();
	private static final EntityType<?>[] MOBS = new EntityType[]{EntityType.SKELETON, EntityType.ZOMBIE, EntityType.ZOMBIE, EntityType.SPIDER};
	private static final BlockState AIR = Blocks.CAVE_AIR.defaultBlockState();

	public MonsterRoomFeature(Codec<NoneFeatureConfiguration> codec) {
		super(codec);
	}

	@Override
	public boolean place(FeaturePlaceContext<NoneFeatureConfiguration> context) {
		Predicate<BlockState> predicate = Feature.isReplaceable(BlockTags.FEATURES_CANNOT_REPLACE);
		BlockPos blockPos = context.origin();
		RandomSource randomSource = context.random();
		WorldGenLevel worldGenLevel = context.level();
		int i = 3;
		int j = randomSource.nextInt(2) + 2;
		int k = -j - 1;
		int l = j + 1;
		int m = -1;
		int n = 4;
		int o = randomSource.nextInt(2) + 2;
		int p = -o - 1;
		int q = o + 1;
		int r = 0;

		for (int s = k; s <= l; s++) {
			for (int t = -1; t <= 4; t++) {
				for (int u = p; u <= q; u++) {
					BlockPos blockPos2 = blockPos.offset(s, t, u);
					boolean bl = worldGenLevel.getBlockState(blockPos2).isSolid();
					if (t == -1 && !bl) {
						return false;
					}

					if (t == 4 && !bl) {
						return false;
					}

					if ((s == k || s == l || u == p || u == q) && t == 0 && worldGenLevel.isEmptyBlock(blockPos2) && worldGenLevel.isEmptyBlock(blockPos2.above())) {
						r++;
					}
				}
			}
		}

		if (r >= 1 && r <= 5) {
			for (int s = k; s <= l; s++) {
				for (int t = 3; t >= -1; t--) {
					for (int u = p; u <= q; u++) {
						BlockPos blockPos2x = blockPos.offset(s, t, u);
						BlockState blockState = worldGenLevel.getBlockState(blockPos2x);
						if (s == k || t == -1 || u == p || s == l || t == 4 || u == q) {
							if (blockPos2x.getY() >= worldGenLevel.getMinY() && !worldGenLevel.getBlockState(blockPos2x.below()).isSolid()) {
								worldGenLevel.setBlock(blockPos2x, AIR, 2);
							} else if (blockState.isSolid() && !blockState.is(Blocks.CHEST)) {
								if (t == -1 && randomSource.nextInt(4) != 0) {
									this.safeSetBlock(worldGenLevel, blockPos2x, Blocks.MOSSY_COBBLESTONE.defaultBlockState(), predicate);
								} else {
									this.safeSetBlock(worldGenLevel, blockPos2x, Blocks.COBBLESTONE.defaultBlockState(), predicate);
								}
							}
						} else if (!blockState.is(Blocks.CHEST) && !blockState.is(Blocks.SPAWNER)) {
							this.safeSetBlock(worldGenLevel, blockPos2x, AIR, predicate);
						}
					}
				}
			}

			for (int s = 0; s < 2; s++) {
				for (int t = 0; t < 3; t++) {
					int ux = blockPos.getX() + randomSource.nextInt(j * 2 + 1) - j;
					int v = blockPos.getY();
					int w = blockPos.getZ() + randomSource.nextInt(o * 2 + 1) - o;
					BlockPos blockPos3 = new BlockPos(ux, v, w);
					if (worldGenLevel.isEmptyBlock(blockPos3)) {
						int x = 0;

						for (Direction direction : Direction.Plane.HORIZONTAL) {
							if (worldGenLevel.getBlockState(blockPos3.relative(direction)).isSolid()) {
								x++;
							}
						}

						if (x == 1) {
							this.safeSetBlock(worldGenLevel, blockPos3, StructurePiece.reorient(worldGenLevel, blockPos3, Blocks.CHEST.defaultBlockState()), predicate);
							RandomizableContainer.setBlockEntityLootTable(worldGenLevel, randomSource, blockPos3, BuiltInLootTables.SIMPLE_DUNGEON);
							break;
						}
					}
				}
			}

			this.safeSetBlock(worldGenLevel, blockPos, Blocks.SPAWNER.defaultBlockState(), predicate);
			if (worldGenLevel.getBlockEntity(blockPos) instanceof SpawnerBlockEntity spawnerBlockEntity) {
				spawnerBlockEntity.setEntityId(this.randomEntityId(randomSource), randomSource);
			} else {
				LOGGER.error("Failed to fetch mob spawner entity at ({}, {}, {})", blockPos.getX(), blockPos.getY(), blockPos.getZ());
			}

			return true;
		} else {
			return false;
		}
	}

	private EntityType<?> randomEntityId(RandomSource random) {
		return Util.getRandom(MOBS, random);
	}
}