package net.minecraft.client.renderer.feature.phase;

import com.google.common.primitives.Floats;
import it.unimi.dsi.fastutil.floats.FloatArrayList;
import it.unimi.dsi.fastutil.floats.FloatList;
import it.unimi.dsi.fastutil.ints.IntArrays;
import java.util.ArrayList;
import java.util.List;
import net.fabricmc.api.EnvType;
import net.fabricmc.api.Environment;
import net.minecraft.client.renderer.feature.submit.SubmitNode;
import net.minecraft.client.renderer.feature.submit.TranslucentSubmit;

@Environment(EnvType.CLIENT)
public class TranslucentFeatureRenderPhase implements FeatureRenderPhase<TranslucentSubmit> {
	private final List<TranslucentSubmit> submits = new ArrayList();
	private final FloatList distances = new FloatArrayList();

	public void submit(final TranslucentSubmit submit) {
		this.submits.add(submit);
		this.distances.add(submit.distanceToCameraSq());
	}

	@Override
	public void sortInto(final FeatureRenderPhase.Output output) {
		if (!this.submits.isEmpty()) {
			for (int index : this.sortIndices()) {
				output.accept((SubmitNode)this.submits.get(index), true);
			}

			this.submits.clear();
			this.distances.clear();
		}
	}

	private int[] sortIndices() {
		int[] indices = new int[this.submits.size()];
		int i = 0;

		while (i < this.submits.size()) {
			indices[i] = i++;
		}

		IntArrays.unstableSort(indices, (i1, i2) -> Floats.compare(this.distances.getFloat(i2), this.distances.getFloat(i1)));
		return indices;
	}

	@Override
	public boolean isEmpty() {
		return this.submits.isEmpty();
	}
}