package net.minecraft.world.entity;

import java.util.List;
import java.util.function.Consumer;
import java.util.function.Predicate;
import java.util.function.Supplier;
import net.minecraft.world.item.ItemStack;

public interface SlotAccess {
	ItemStack get();

	boolean set(ItemStack itemStack);

	static SlotAccess of(final Supplier<ItemStack> getter, final Consumer<ItemStack> setter) {
		return new SlotAccess() {
			@Override
			public ItemStack get() {
				return (ItemStack)getter.get();
			}

			@Override
			public boolean set(final ItemStack itemStack) {
				setter.accept(itemStack);
				return true;
			}
		};
	}

	static SlotAccess forEquipmentSlot(final LivingEntity entity, final EquipmentSlot slot, final Predicate<ItemStack> validator) {
		return new SlotAccess() {
			@Override
			public ItemStack get() {
				return entity.getItemBySlot(slot);
			}

			@Override
			public boolean set(final ItemStack itemStack) {
				if (!validator.test(itemStack)) {
					return false;
				} else {
					entity.setItemSlot(slot, itemStack);
					return true;
				}
			}
		};
	}

	static SlotAccess forEquipmentSlot(final LivingEntity entity, final EquipmentSlot slot) {
		return forEquipmentSlot(entity, slot, stack -> true);
	}

	static SlotAccess forListElement(final List<ItemStack> stacks, final int index) {
		return new SlotAccess() {
			@Override
			public ItemStack get() {
				return (ItemStack)stacks.get(index);
			}

			@Override
			public boolean set(final ItemStack itemStack) {
				stacks.set(index, itemStack);
				return true;
			}
		};
	}
}