@Override public ItemStack transferStackInSlot(EntityPlayer player, int slotID) { ItemStack stack = null; Slot currentSlot = (Slot) inventorySlots.get(slotID); if (currentSlot != null && currentSlot.getHasStack()) { ItemStack slotStack = currentSlot.getStack(); stack = slotStack.copy(); if (slotID == 2 || slotID == 4) { if (!mergeItemStack(slotStack, 5, inventorySlots.size(), true)) { return null; } } else if (ChargeUtils.canBeDischarged(slotStack)) { if (slotID != 1) { if (!mergeItemStack(slotStack, 1, 2, false)) { return null; } } else if (slotID == 1) { if (!mergeItemStack(slotStack, 5, inventorySlots.size(), true)) { return null; } } } else if (RecipeHandler.getChanceOutput(slotStack, false, tileEntity.getRecipes()) != null) { if (slotID != 0 && slotID != 1 && slotID != 2 && slotID != 3 && slotID != 4) { if (!mergeItemStack(slotStack, 0, 1, false)) { return null; } } else { if (!mergeItemStack(slotStack, 5, inventorySlots.size(), true)) { return null; } } } else if (slotStack.getItem() instanceof ItemMachineUpgrade) { if (slotID != 0 && slotID != 1 && slotID != 2 && slotID != 3) { if (!mergeItemStack(slotStack, 3, 4, false)) { return null; } } else { if (!mergeItemStack(slotStack, 5, inventorySlots.size(), true)) { return null; } } } else { if (slotID >= 5 && slotID <= 31) { if (!mergeItemStack(slotStack, 32, inventorySlots.size(), false)) { return null; } } else if (slotID > 31) { if (!mergeItemStack(slotStack, 5, 31, false)) { return null; } } else { if (!mergeItemStack(slotStack, 5, inventorySlots.size(), true)) { return null; } } } if (slotStack.stackSize == 0) { currentSlot.putStack((ItemStack) null); } else { currentSlot.onSlotChanged(); } if (slotStack.stackSize == stack.stackSize) { return null; } currentSlot.onPickupFromSlot(player, slotStack); } return stack; }