package net.minecraft.server.level;

import net.minecraft.world.level.ChunkPos;
import net.minecraft.world.level.lighting.DynamicGraphMinFixedPoint;

public abstract class ChunkTracker extends DynamicGraphMinFixedPoint {
	protected ChunkTracker(int i, int j, int k) {
		super(i, j, k);
	}

	@Override
	protected boolean isSource(long pos) {
		return pos == ChunkPos.INVALID_CHUNK_POS;
	}

	@Override
	protected void checkNeighborsAfterUpdate(long pos, int level, boolean isDecreasing) {
		if (!isDecreasing || level < this.levelCount - 2) {
			ChunkPos chunkPos = new ChunkPos(pos);
			int i = chunkPos.x;
			int j = chunkPos.z;

			for (int k = -1; k <= 1; k++) {
				for (int l = -1; l <= 1; l++) {
					long m = ChunkPos.asLong(i + k, j + l);
					if (m != pos) {
						this.checkNeighbor(pos, m, level, isDecreasing);
					}
				}
			}
		}
	}

	@Override
	protected int getComputedLevel(long pos, long excludedSourcePos, int level) {
		int i = level;
		ChunkPos chunkPos = new ChunkPos(pos);
		int j = chunkPos.x;
		int k = chunkPos.z;

		for (int l = -1; l <= 1; l++) {
			for (int m = -1; m <= 1; m++) {
				long n = ChunkPos.asLong(j + l, k + m);
				if (n == pos) {
					n = ChunkPos.INVALID_CHUNK_POS;
				}

				if (n != excludedSourcePos) {
					int o = this.computeLevelFromNeighbor(n, pos, this.getLevel(n));
					if (i > o) {
						i = o;
					}

					if (i == 0) {
						return i;
					}
				}
			}
		}

		return i;
	}

	@Override
	protected int computeLevelFromNeighbor(long startPos, long endPos, int startLevel) {
		return startPos == ChunkPos.INVALID_CHUNK_POS ? this.getLevelFromSource(endPos) : startLevel + 1;
	}

	protected abstract int getLevelFromSource(long pos);

	public void update(long pos, int level, boolean isDecreasing) {
		this.checkEdge(ChunkPos.INVALID_CHUNK_POS, pos, level, isDecreasing);
	}
}