package net.minecraft.advancements;

import com.google.common.annotations.VisibleForTesting;
import it.unimi.dsi.fastutil.objects.ReferenceOpenHashSet;
import java.util.Set;
import org.jetbrains.annotations.Nullable;

public class AdvancementNode {
	private final AdvancementHolder holder;
	@Nullable
	private final AdvancementNode parent;
	private final Set<AdvancementNode> children = new ReferenceOpenHashSet<>();

	@VisibleForTesting
	public AdvancementNode(AdvancementHolder holder, @Nullable AdvancementNode parent) {
		this.holder = holder;
		this.parent = parent;
	}

	public Advancement advancement() {
		return this.holder.value();
	}

	public AdvancementHolder holder() {
		return this.holder;
	}

	@Nullable
	public AdvancementNode parent() {
		return this.parent;
	}

	public AdvancementNode root() {
		return getRoot(this);
	}

	public static AdvancementNode getRoot(AdvancementNode node) {
		AdvancementNode advancementNode = node;

		while (true) {
			AdvancementNode advancementNode2 = advancementNode.parent();
			if (advancementNode2 == null) {
				return advancementNode;
			}

			advancementNode = advancementNode2;
		}
	}

	public Iterable<AdvancementNode> children() {
		return this.children;
	}

	@VisibleForTesting
	public void addChild(AdvancementNode child) {
		this.children.add(child);
	}

	public boolean equals(Object object) {
		return this == object ? true : object instanceof AdvancementNode advancementNode && this.holder.equals(advancementNode.holder);
	}

	public int hashCode() {
		return this.holder.hashCode();
	}

	public String toString() {
		return this.holder.id().toString();
	}
}