fake chest menu base class

ServerSideChest.java

package random832.gui.menu;

import com.mojang.authlib.GameProfile;
import net.minecraft.MethodsReturnNonnullByDefault;
import net.minecraft.Util;
import net.minecraft.server.level.ServerLevel;
import net.minecraft.world.Container;
import net.minecraft.world.SimpleContainer;
import net.minecraft.world.entity.player.Inventory;
import net.minecraft.world.entity.player.Player;
import net.minecraft.world.inventory.*;
import net.minecraft.world.item.ItemStack;
import net.minecraftforge.common.util.FakePlayer;
import net.minecraftforge.common.util.FakePlayerFactory;
import net.minecraftforge.server.ServerLifecycleHooks;

import javax.annotation.ParametersAreNonnullByDefault;
import java.util.function.BiFunction;

/**
 * Helper class for building server-side menus that use the chest menu on the client.
 */
@ParametersAreNonnullByDefault
@MethodsReturnNonnullByDefault
public  abstract class ServerSideChest extends AbstractContainerMenu {
    final ChestMenu chestMenu;
    final FakePlayer chestPlayer;

    /**
     * @param menuFactory e.g. {@link ChestMenu#threeRows(int, Inventory)} 
     */
    protected ServerSideChest(int containerId, BiFunction<Integer, Inventory, ChestMenu> menuFactory) {
        super(null, containerId);
        ServerLevel overworld = ServerLifecycleHooks.getCurrentServer().overworld();
        chestPlayer = FakePlayerFactory.get(overworld,  new GameProfile(Util.NIL_UUID, "FakeChestUser"));
        chestMenu = menuFactory.apply(-42, chestPlayer.getInventory());
    }

    protected final void fillExtraSlots() {
        int n = slots.size();
        while (n < chestMenu.slots.size()) {
            addSlot(new EmptySlot());
        }
    }

    @Override
    public final MenuType<?> getType() {
        return chestMenu.getType();
    }

    @Override
    public void clicked(int slotIndex, int eventButton, ClickType clickType, Player player) {
        for(int i=0; i<chestMenu.slots.size(); i++) {
            chestMenu.setItem(i, -42, remoteSlots.get(i));
        }
        chestMenu.setRemoteCarried(getCarried());
        chestMenu.clicked(slotIndex, eventButton, clickType, chestPlayer);
        super.clicked(slotIndex, eventButton, clickType, player);
        for (Slot slot : chestMenu.slots) {
            setRemoteSlotNoCopy(slot.index, slot.getItem());
        }
        setRemoteCarried(chestMenu.getCarried());
    }

    private static class EmptySlot extends Slot {
        private static final Container EMPTY_CONTAINER = new SimpleContainer(0);

        public EmptySlot() {
            super(EMPTY_CONTAINER, 0, 0, 0);
        }

        @Override
        public ItemStack getItem() {
            return ItemStack.EMPTY;
        }

        @Override
        public boolean isSameInventory(Slot other) {
            return other instanceof EmptySlot;
        }

        @Override
        public boolean allowModification(Player p_150652_) {
            return false;
        }

        @Override
        public boolean mayPlace(ItemStack pStack) {
            return false;
        }
    }
}