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

import com.mojang.serialization.Codec;
import net.minecraft.core.BlockPos;
import net.minecraft.util.RandomSource;
import net.minecraft.world.level.WorldGenLevel;
import net.minecraft.world.level.levelgen.feature.configurations.BlockColumnConfiguration;

public class BlockColumnFeature extends Feature<BlockColumnConfiguration> {
	public BlockColumnFeature(final Codec<BlockColumnConfiguration> codec) {
		super(codec);
	}

	@Override
	public boolean place(final FeaturePlaceContext<BlockColumnConfiguration> context) {
		WorldGenLevel level = context.level();
		BlockColumnConfiguration config = context.config();
		RandomSource random = context.random();
		int layerCount = config.layers().size();
		int[] layerHeights = new int[layerCount];
		int totalHeight = 0;

		for (int i = 0; i < layerCount; i++) {
			layerHeights[i] = ((BlockColumnConfiguration.Layer)config.layers().get(i)).height().sample(random);
			totalHeight += layerHeights[i];
		}

		if (totalHeight == 0) {
			return false;
		} else {
			BlockPos.MutableBlockPos placePos = context.origin().mutable();
			BlockPos.MutableBlockPos nextPos = placePos.mutable().move(config.direction());

			for (int y = 0; y < totalHeight; y++) {
				if (!config.allowedPlacement().test(level, nextPos)) {
					truncate(layerHeights, totalHeight, y, config.prioritizeTip());
					break;
				}

				nextPos.move(config.direction());
			}

			for (int i = 0; i < layerCount; i++) {
				int count = layerHeights[i];
				if (count != 0) {
					BlockColumnConfiguration.Layer layer = (BlockColumnConfiguration.Layer)config.layers().get(i);

					for (int y = 0; y < count; y++) {
						level.setBlock(placePos, layer.state().getState(level, random, placePos), 2);
						placePos.move(config.direction());
					}
				}
			}

			return true;
		}
	}

	private static void truncate(final int[] layerHeights, final int totalHeight, final int newHeight, final boolean prioritizeTip) {
		int amountToRemove = totalHeight - newHeight;
		int direction = prioritizeTip ? 1 : -1;
		int start = prioritizeTip ? 0 : layerHeights.length - 1;
		int end = prioritizeTip ? layerHeights.length : -1;

		for (int i = start; i != end && amountToRemove > 0; i += direction) {
			int thisLayer = layerHeights[i];
			int toRemoveFromLayer = Math.min(thisLayer, amountToRemove);
			amountToRemove -= toRemoveFromLayer;
			layerHeights[i] -= toRemoveFromLayer;
		}
	}
}