package net.minecraft.network.chat;

import it.unimi.dsi.fastutil.objects.ObjectArrayList;
import it.unimi.dsi.fastutil.objects.ObjectList;
import java.util.BitSet;
import java.util.Objects;
import javax.annotation.Nullable;

public class LastSeenMessagesTracker {
    private final LastSeenTrackedEntry[] trackedMessages;
    private int tail;
    private int offset;
    @Nullable
    private MessageSignature lastTrackedMessage;

    public LastSeenMessagesTracker(int p_242388_) {
        this.trackedMessages = new LastSeenTrackedEntry[p_242388_];
    }

    public boolean addPending(MessageSignature p_248926_, boolean p_250312_) {
        if (Objects.equals(p_248926_, this.lastTrackedMessage)) {
            return false;
        } else {
            this.lastTrackedMessage = p_248926_;
            this.addEntry(p_250312_ ? new LastSeenTrackedEntry(p_248926_, true) : null);
            return true;
        }
    }

    private void addEntry(@Nullable LastSeenTrackedEntry p_250255_) {
        int i = this.tail;
        this.tail = (i + 1) % this.trackedMessages.length;
        this.offset++;
        this.trackedMessages[i] = p_250255_;
    }

    public void ignorePending(MessageSignature p_251020_) {
        for (int i = 0; i < this.trackedMessages.length; i++) {
            LastSeenTrackedEntry lastseentrackedentry = this.trackedMessages[i];
            if (lastseentrackedentry != null && lastseentrackedentry.pending() && p_251020_.equals(lastseentrackedentry.signature())) {
                this.trackedMessages[i] = null;
                break;
            }
        }
    }

    public int getAndClearOffset() {
        int i = this.offset;
        this.offset = 0;
        return i;
    }

    public LastSeenMessagesTracker.Update generateAndApplyUpdate() {
        int i = this.getAndClearOffset();
        BitSet bitset = new BitSet(this.trackedMessages.length);
        ObjectList<MessageSignature> objectlist = new ObjectArrayList<>(this.trackedMessages.length);

        for (int j = 0; j < this.trackedMessages.length; j++) {
            int k = (this.tail + j) % this.trackedMessages.length;
            LastSeenTrackedEntry lastseentrackedentry = this.trackedMessages[k];
            if (lastseentrackedentry != null) {
                bitset.set(j, true);
                objectlist.add(lastseentrackedentry.signature());
                this.trackedMessages[k] = lastseentrackedentry.acknowledge();
            }
        }

        LastSeenMessages lastseenmessages = new LastSeenMessages(objectlist);
        LastSeenMessages.Update lastseenmessages$update = new LastSeenMessages.Update(i, bitset, lastseenmessages.computeChecksum());
        return new LastSeenMessagesTracker.Update(lastseenmessages, lastseenmessages$update);
    }

    public int offset() {
        return this.offset;
    }

    public record Update(LastSeenMessages lastSeen, LastSeenMessages.Update update) {
    }
}