Code/net/minecraft/world/level/lighting/LeveledPriorityQueue.java

package net.minecraft.world.level.lighting;

import it.unimi.dsi.fastutil.longs.LongLinkedOpenHashSet;

public class LeveledPriorityQueue {
    private final int levelCount;
    private final LongLinkedOpenHashSet[] queues;
    private int firstQueuedLevel;

    public LeveledPriorityQueue(int p_278289_, final int p_278259_) {
        this.levelCount = p_278289_;
        this.queues = new LongLinkedOpenHashSet[p_278289_];

        for (int i = 0; i < p_278289_; i++) {
            this.queues[i] = new LongLinkedOpenHashSet(p_278259_, 0.5F) {
                @Override
                protected void rehash(int p_278313_) {
                    if (p_278313_ > p_278259_) {
                        super.rehash(p_278313_);
                    }
                }
            };
        }

        this.firstQueuedLevel = p_278289_;
    }

    public long removeFirstLong() {
        LongLinkedOpenHashSet longlinkedopenhashset = this.queues[this.firstQueuedLevel];
        long i = longlinkedopenhashset.removeFirstLong();
        if (longlinkedopenhashset.isEmpty()) {
            this.checkFirstQueuedLevel(this.levelCount);
        }

        return i;
    }

    public boolean isEmpty() {
        return this.firstQueuedLevel >= this.levelCount;
    }

    public void dequeue(long p_278232_, int p_278338_, int p_278345_) {
        LongLinkedOpenHashSet longlinkedopenhashset = this.queues[p_278338_];
        longlinkedopenhashset.remove(p_278232_);
        if (longlinkedopenhashset.isEmpty() && this.firstQueuedLevel == p_278338_) {
            this.checkFirstQueuedLevel(p_278345_);
        }
    }

    public void enqueue(long p_278311_, int p_278335_) {
        this.queues[p_278335_].add(p_278311_);
        if (this.firstQueuedLevel > p_278335_) {
            this.firstQueuedLevel = p_278335_;
        }
    }

    private void checkFirstQueuedLevel(int p_278303_) {
        int i = this.firstQueuedLevel;
        this.firstQueuedLevel = p_278303_;

        for (int j = i + 1; j < p_278303_; j++) {
            if (!this.queues[j].isEmpty()) {
                this.firstQueuedLevel = j;
                break;
            }
        }
    }
}