I was trying to create a helmet where every time is equipped, consume 1 gold nugget every 1 second, but sometimes when the number of gold nuggets come to zero, appear more gold nuggets.So what i am doing wrong?
 
	 
 
	 
 
	public class BatMask extends ArmorBase{ 
	    int cooldown=0;//time left to consume another gold nugget 
	    public BatMask(String name, ArmorMaterial materialIn, int renderIndexIn, EntityEquipmentSlot equipmentSlotIn) { 
	        super(name, materialIn, renderIndexIn, equipmentSlotIn);                                 
	    }
 
	    @Override 
	    public void onArmorTick (World world, EntityPlayer player, ItemStack itemStack) 
	    { 
	        if(cooldown > -4)cooldown--; 
	        if(cooldown <= 0 && player.inventory.hasItemStack(new ItemStack(Items.GOLD_NUGGET))) { 
	            cooldown = 20; 
	            int i = player.inventory.getSlotFor(new ItemStack(Items.GOLD_NUGGET)); 
	            player.inventory.getStackInSlot(i).shrink(1); 
	        }       
	    } 
	}