package net.minecraft.util;

import it.unimi.dsi.fastutil.objects.Object2IntMap;
import it.unimi.dsi.fastutil.objects.Object2IntOpenHashMap;

public class ClassTreeIdRegistry {
	public static final int NO_ID_VALUE = -1;
	private final Object2IntMap<Class<?>> classToLastIdCache = Util.make(new Object2IntOpenHashMap<>(), map -> map.defaultReturnValue(-1));

	public int getLastIdFor(final Class<?> clazz) {
		int id = this.classToLastIdCache.getInt(clazz);
		if (id != -1) {
			return id;
		} else {
			Class<?> superclass = clazz;

			while ((superclass = superclass.getSuperclass()) != Object.class) {
				int newId = this.classToLastIdCache.getInt(superclass);
				if (newId != -1) {
					return newId;
				}
			}

			return -1;
		}
	}

	public int getCount(final Class<?> clazz) {
		return this.getLastIdFor(clazz) + 1;
	}

	public int define(final Class<?> clazz) {
		int id = this.getLastIdFor(clazz);
		int nextId = id == -1 ? 0 : id + 1;
		this.classToLastIdCache.put(clazz, nextId);
		return nextId;
	}
}