NotEnoughItems/src/main/java/codechicken/nei/ExtendedCreativeInv.java

package codechicken.nei;

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

import cpw.mods.fml.relauncher.Side;

public class ExtendedCreativeInv implements IInventory {

    final PlayerSave playerSave;
    final Side side;

    public ExtendedCreativeInv(PlayerSave playerSave, Side side) {
        this.playerSave = playerSave;
        this.side = side;
    }

    @Override
    public int getSizeInventory() {
        return 54;
    }

    @Override
    public ItemStack getStackInSlot(int slot) {
        if (side.isClient()) return NEIClientConfig.creativeInv[slot];
        return playerSave.creativeInv[slot];
    }

    @Override
    public ItemStack decrStackSize(int slot, int size) {
        ItemStack item = getStackInSlot(slot);

        if (item != null) {
            if (item.stackSize <= size) {
                setInventorySlotContents(slot, null);
                markDirty();
                return item;
            }
            ItemStack itemstack1 = item.splitStack(size);
            if (item.stackSize == 0) {
                setInventorySlotContents(slot, null);
            }
            markDirty();
            return itemstack1;
        }
        return null;
    }

    @Override
    public ItemStack getStackInSlotOnClosing(int slot) {
        synchronized (this) {
            ItemStack stack = getStackInSlot(slot);
            setInventorySlotContents(slot, null);
            return stack;
        }
    }

    @Override
    public void setInventorySlotContents(int slot, ItemStack stack) {
        if (side.isClient()) NEIClientConfig.creativeInv[slot] = stack;
        else playerSave.creativeInv[slot] = stack;

        markDirty();
    }

    @Override
    public String getInventoryName() {
        return "Extended Creative";
    }

    @Override
    public int getInventoryStackLimit() {
        return 64;
    }

    @Override
    public void markDirty() {
        if (side.isServer()) playerSave.setCreativeDirty();
    }

    @Override
    public boolean isUseableByPlayer(EntityPlayer var1) {
        return true;
    }

    @Override
    public void openInventory() {}

    @Override
    public void closeInventory() {}

    @Override
    public boolean isItemValidForSlot(int slot, ItemStack stack) {
        return true;
    }

    @Override
    public boolean hasCustomInventoryName() {
        return true;
    }
}