ContainerPlayerInterface.java

package com.austinv11.peripheralsplusplus.tiles.containers;

import com.austinv11.collectiveframework.minecraft.inventory.ExclusiveSlot;
import com.austinv11.peripheralsplusplus.init.ModItems;
import net.minecraft.entity.player.EntityPlayer;
import net.minecraft.inventory.Container;
import net.minecraft.inventory.IInventory;
import net.minecraft.inventory.Slot;
import net.minecraft.item.Item;
import net.minecraft.item.ItemStack;

import java.util.HashSet;
import java.util.Set;

public class ContainerPlayerInterface extends Container
{
    private IInventory inv;
    private EntityPlayer player;

    public ContainerPlayerInterface(EntityPlayer player, IInventory inv, int xSize, int ySize)
    {
        this.inv = inv;
        this.player = player;
        inv.openInventory();
        layout(xSize, ySize);
    }

    protected void layout(int xSize, int ySize)
    {
        for (int invSlot = 0; invSlot < 8; invSlot++) {
            ExclusiveSlot slot = new ExclusiveSlot(inv, invSlot, invSlot * 18 + 16, 35);
            slot.setWhitelist(true);
            Set<Item> items = new HashSet<Item>();
            items.add(ModItems.permCard);
            slot.setExclusive(items);
            addSlotToContainer(slot);
        }

        int leftCol = (xSize - 162) / 2 + 1;
        for (int playerInvRow = 0; playerInvRow < 3; playerInvRow++)
        {
            for (int playerInvCol = 0; playerInvCol < 9; playerInvCol++)
            {
                addSlotToContainer(new Slot(player.inventory, playerInvCol + playerInvRow * 9 + 9, leftCol + playerInvCol * 18, ySize - (4 - playerInvRow) * 18 + 7));
            }
        }
        for (int hotbarSlot = 0; hotbarSlot < 9; hotbarSlot++)
        {
            addSlotToContainer(new Slot(player.inventory, hotbarSlot, leftCol + hotbarSlot * 18, ySize - 7));
        }
    }

    @Override
    public boolean canInteractWith(EntityPlayer player)
    {
        return inv.isUseableByPlayer(player);
    }

    @Override
    public ItemStack transferStackInSlot(EntityPlayer entityPlayer, int slotIndex)
    {
        // Create a new itemstack. This is the stack that will be manipulated and returned.
        ItemStack itemstack = null;
        // Get the slot that was just shift clicked. This is the slot that the itemstack will be transferring from.
        Slot slot = (Slot) this.inventorySlots.get(slotIndex);

        // Check that the slot exists and has an itemstack in it
        if (slot != null && slot.getHasStack())
        {
            // Get the stack in the slot that was shift-clicked. This stack will act as a base for our return itemstack.
            ItemStack itemstack1 = slot.getStack();

            if (!itemstack1.getItem().equals(ModItems.permCard))
            {
                return null;
            }

            // Copy that stack to our return itemstack.
            itemstack = itemstack1.copy();

            if (slotIndex < inv.getSizeInventory()) // If the slot being transferred from is in the force belt inventory.
            {
                if (!this.mergeItemStack(itemstack1, inv.getSizeInventory(), 36 + inv.getSizeInventory(), true)) // Tries to merge itemstack with any in the player's main inv. (slots 8-44) 36 is the player's main inv size (excludes armor slots)
                {
                    return null;
                }
            }
            else if (!this.mergeItemStack(itemstack1, 0, inv.getSizeInventory(), false)) // If the itemstack can't merge with any stacks in the force belt container, return.
            {                                                       // Implies that the stack being transferred is from a slot in the player's main inv
                return null;
            }

            // After the merging has completed, if the itemstack has a size of 0, replace it with an empty slot.
            if (itemstack1.stackSize == 0)
            {
                slot.putStack(null);
            }
            else
            {
                // Inform the game that the slot was changed.
                slot.onSlotChanged();
            }
        }

        // Return the new itemstack. This is the itemstack that will be placed in the slot that is being transferred to.
        return itemstack;
    }
}