Action buy = Properties.REVERSE_BUTTONS ? LEFT_CLICK_BLOCK : RIGHT_CLICK_BLOCK;
double price = (action == buy ? PriceUtil.getBuyPrice(prices) : PriceUtil.getSellPrice(prices));
Chest chest = uBlock.findConnectedChest(sign);
Inventory ownerInventory = (ChestShopSign.isAdminShop(sign) ? new AdminInventory() : chest != null ? chest.getInventory() : null);
ItemStack item = MaterialUtil.getItem(material);
if (item == null || !NumberUtil.isInteger(quantity)) {
player.sendMessage(Messages.prefix(Messages.INVALID_SHOP_DETECTED));