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

import com.google.common.collect.ImmutableList;
import com.mojang.serialization.Codec;
import net.minecraft.core.BlockPos;
import net.minecraft.core.Direction;
import net.minecraft.util.RandomSource;
import net.minecraft.world.level.LevelAccessor;
import net.minecraft.world.level.WorldGenLevel;
import net.minecraft.world.level.block.Block;
import net.minecraft.world.level.block.Blocks;
import net.minecraft.world.level.block.state.BlockState;
import net.minecraft.world.level.levelgen.feature.configurations.DeltaFeatureConfiguration;

public class DeltaFeature extends Feature<DeltaFeatureConfiguration> {
	private static final ImmutableList<Block> CANNOT_REPLACE = ImmutableList.of(
		Blocks.BEDROCK, Blocks.NETHER_BRICKS, Blocks.NETHER_BRICK_FENCE, Blocks.NETHER_BRICK_STAIRS, Blocks.NETHER_WART, Blocks.CHEST, Blocks.SPAWNER
	);
	private static final Direction[] DIRECTIONS = Direction.values();
	private static final double RIM_SPAWN_CHANCE = 0.9;

	public DeltaFeature(Codec<DeltaFeatureConfiguration> codec) {
		super(codec);
	}

	@Override
	public boolean place(FeaturePlaceContext<DeltaFeatureConfiguration> context) {
		boolean bl = false;
		RandomSource randomSource = context.random();
		WorldGenLevel worldGenLevel = context.level();
		DeltaFeatureConfiguration deltaFeatureConfiguration = context.config();
		BlockPos blockPos = context.origin();
		boolean bl2 = randomSource.nextDouble() < 0.9;
		int i = bl2 ? deltaFeatureConfiguration.rimSize().sample(randomSource) : 0;
		int j = bl2 ? deltaFeatureConfiguration.rimSize().sample(randomSource) : 0;
		boolean bl3 = bl2 && i != 0 && j != 0;
		int k = deltaFeatureConfiguration.size().sample(randomSource);
		int l = deltaFeatureConfiguration.size().sample(randomSource);
		int m = Math.max(k, l);

		for (BlockPos blockPos2 : BlockPos.withinManhattan(blockPos, k, 0, l)) {
			if (blockPos2.distManhattan(blockPos) > m) {
				break;
			}

			if (isClear(worldGenLevel, blockPos2, deltaFeatureConfiguration)) {
				if (bl3) {
					bl = true;
					this.setBlock(worldGenLevel, blockPos2, deltaFeatureConfiguration.rim());
				}

				BlockPos blockPos3 = blockPos2.offset(i, 0, j);
				if (isClear(worldGenLevel, blockPos3, deltaFeatureConfiguration)) {
					bl = true;
					this.setBlock(worldGenLevel, blockPos3, deltaFeatureConfiguration.contents());
				}
			}
		}

		return bl;
	}

	private static boolean isClear(LevelAccessor level, BlockPos pos, DeltaFeatureConfiguration config) {
		BlockState blockState = level.getBlockState(pos);
		if (blockState.is(config.contents().getBlock())) {
			return false;
		} else if (CANNOT_REPLACE.contains(blockState.getBlock())) {
			return false;
		} else {
			for (Direction direction : DIRECTIONS) {
				boolean bl = level.getBlockState(pos.relative(direction)).isAir();
				if (bl && direction != Direction.UP || !bl && direction == Direction.UP) {
					return false;
				}
			}

			return true;
		}
	}
}