SlotDummy.java

package codechicken.core.inventory;

import codechicken.lib.inventory.InventoryUtils;
import net.minecraft.entity.player.EntityPlayer;
import net.minecraft.inventory.IInventory;
import net.minecraft.item.ItemStack;

public class SlotDummy extends SlotHandleClicks {
    public final int stackLimit;

    public SlotDummy(IInventory inv, int slot, int x, int y) {
        this(inv, slot, x, y, 64);
    }

    public SlotDummy(IInventory inv, int slot, int x, int y, int limit) {
        super(inv, slot, x, y);
        stackLimit = limit;
    }

    @Override
    public ItemStack slotClick(ContainerExtended container, EntityPlayer player, int button, int modifier) {
        ItemStack held = player.inventory.getItemStack();
        boolean shift = modifier == 1;
        slotClick(held, button, shift);
        return null;
    }

    public void slotClick(ItemStack held, int button, boolean shift) {
        ItemStack tstack = getStack();
        if (held != null && (tstack == null || !InventoryUtils.canStack(held, tstack))) {
            int quantity = Math.min(held.stackSize, stackLimit);
            if (shift) {
                quantity = Math.min(stackLimit, held.getMaxStackSize() * 16);
            }
            if (button == 1) {
                quantity = 1;
            }
            putStack(InventoryUtils.copyStack(held, quantity));
        } else if (tstack != null) {
            int inc;
            if (held != null) {
                inc = button == 1 ? -held.stackSize : held.stackSize;
                if (shift) {
                    inc *= 16;
                }
            } else {
                inc = button == 1 ? -1 : 1;
                if (shift) {
                    inc *= 16;
                }
            }
            int quantity = tstack.stackSize + inc;
            if (quantity <= 0) {
                putStack(null);
            } else {
                putStack(InventoryUtils.copyStack(tstack, quantity));
            }
        }
    }

    @Override
    public void putStack(ItemStack stack) {
        if (stack != null && stack.stackSize > stackLimit) {
            stack = InventoryUtils.copyStack(stack, stackLimit);
        }
        super.putStack(stack);
    }
}