Hi, I'm struggling with automated villager trading. I've extended GuiMerchant, added some buttons and now I'm implementing actual trading.

 

Method that should do the trading is:

 

    void StartTrading()
    {
    	IMerchant villager = getMerchant();
    	EntityPlayer player = villager.getCustomer();
    	MerchantRecipeList trades = villager.getRecipes(player);
    	MerchantRecipe trade = trades.get(0);
    	
ItemStack input = trade.getItemToBuy();
ItemStack materials = getFirstAvailableItemStack(player, input);
if(materials == null)
	return;
ContainerMerchant merchant = ((ContainerMerchant)inventorySlots);
merchant.getMerchantInventory().setInventorySlotContents(0, materials);
    	inventorySlots.transferStackInSlot(player, 2);
    	inventorySlots.transferStackInSlot(player, 0);
    }

 

Method works as expected but as soon as I click on newly acquired emeralds, all changes are reverted. I assume I'm missing something but I can't find any tutorial that would address this problem.

 

getFirstAvailableItemStack method in case you are interested:

 

 

    ItemStack getFirstAvailableItemStack(EntityPlayer player, ItemStack itemStack){

    	for(ItemStack stack:player.inventory.mainInventory){
    		if(stack != null){
    			if(stack.getItem().equals(itemStack.getItem()))
    				return stack;
    		}
    	}
    	return null;
    }

You sre handling the inventory on the clients s8de of things it needs to be handled server side, aince you are trying to make it only client side you should use some of the default packets if there are any.

Yesterday I found a solution to this. I could either send appropriate packets to a server or I could simulate user clicks. I went for second option and it's as simple as

 

 

    	handleMouseClick(slot30, slot30.slotNumber, 0, ClickType.PICKUP);
    	handleMouseClick(slot30, slot30.slotNumber, 0, ClickType.PICKUP_ALL);
    	handleMouseClick(slot0, slot0.slotNumber, 0, ClickType.PICKUP);
    	

    	handleMouseClick(slot2, slot2.slotNumber, 0, ClickType.QUICK_MOVE);