package net.minecraft.world.entity.boss.enderdragon;

import java.util.Arrays;
import net.minecraft.util.Mth;

public class DragonFlightHistory {
	public static final int LENGTH = 64;
	private static final int MASK = 63;
	private final DragonFlightHistory.Sample[] samples = new DragonFlightHistory.Sample[64];
	private int head = -1;

	public DragonFlightHistory() {
		Arrays.fill(this.samples, new DragonFlightHistory.Sample(0.0, 0.0F));
	}

	public void copyFrom(final DragonFlightHistory history) {
		System.arraycopy(history.samples, 0, this.samples, 0, 64);
		this.head = history.head;
	}

	public void record(final double y, final float yRot) {
		DragonFlightHistory.Sample sample = new DragonFlightHistory.Sample(y, yRot);
		if (this.head < 0) {
			Arrays.fill(this.samples, sample);
		}

		if (++this.head == 64) {
			this.head = 0;
		}

		this.samples[this.head] = sample;
	}

	public DragonFlightHistory.Sample get(final int delay) {
		return this.samples[this.head - delay & 63];
	}

	public DragonFlightHistory.Sample get(final int delay, final float partialTicks) {
		DragonFlightHistory.Sample sample = this.get(delay);
		DragonFlightHistory.Sample sampleOld = this.get(delay + 1);
		return new DragonFlightHistory.Sample(Mth.lerp((double)partialTicks, sampleOld.y, sample.y), Mth.rotLerp(partialTicks, sampleOld.yRot, sample.yRot));
	}

	public record Sample(double y, float yRot) {
	}
}