Fix automatic lapis in enchanting tables

src/main/java/net/trueog/oldenchantog/OldEnchantOG.java

@@ -1,14 +1,26 @@
+/*
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/.
+ */
 package net.trueog.oldenchantog;
 
 import org.bukkit.Bukkit;
+import org.bukkit.Material;
 import org.bukkit.event.EventHandler;
 import org.bukkit.event.Listener;
 import org.bukkit.event.enchantment.EnchantItemEvent;
+import org.bukkit.event.inventory.ClickType;
+import org.bukkit.event.inventory.InventoryAction;
 import org.bukkit.event.inventory.InventoryClickEvent;
 import org.bukkit.event.inventory.InventoryCloseEvent;
+import org.bukkit.event.inventory.InventoryDragEvent;
+import org.bukkit.event.inventory.InventoryOpenEvent;
 import org.bukkit.event.inventory.InventoryType;
 import org.bukkit.event.inventory.PrepareAnvilEvent;
+import org.bukkit.inventory.EnchantingInventory;
 import org.bukkit.inventory.Inventory;
+import org.bukkit.inventory.ItemStack;
 import org.bukkit.plugin.java.JavaPlugin;
 
 /**
@@ -20,6 +32,9 @@ import org.bukkit.plugin.java.JavaPlugin;
  */
 public class OldEnchantOG extends JavaPlugin implements Listener {
 
+    private static final int ENCHANTING_LAPIS_SLOT = 1;
+    private static final int AUTO_LAPIS_AMOUNT = 64;
+
     @Override
     public void onEnable() {
 
@@ -27,16 +42,59 @@ public class OldEnchantOG extends JavaPlugin implements Listener {
 
     }
 
+    @EventHandler
+    public void inventoryOpen(InventoryOpenEvent event) {
+
+        fillUpEnchantingTable(event.getInventory());
+
+    }
+
     @EventHandler
     public void inventoryClick(InventoryClickEvent event) {
 
         Inventory inventory = event.getInventory();
-        if (inventory.getType().equals(InventoryType.ENCHANTING) && event.getRawSlot() == 1) {
+        if (!inventory.getType().equals(InventoryType.ENCHANTING)) {
+
+            return;
+
+        }
+
+        if (event.getRawSlot() == ENCHANTING_LAPIS_SLOT) {
+
+            event.setCancelled(true);
+
+        } else if (event.getClick() == ClickType.DOUBLE_CLICK && isLapis(event.getCursor())) {
+
+            event.setCancelled(true);
+
+        } else if (event.getAction() == InventoryAction.MOVE_TO_OTHER_INVENTORY && isLapis(event.getCurrentItem())) {
 
             event.setCancelled(true);
 
         }
 
+        refillEnchantingTableNextTick(inventory);
+
+    }
+
+    @EventHandler
+    public void inventoryDrag(InventoryDragEvent event) {
+
+        Inventory inventory = event.getInventory();
+        if (!inventory.getType().equals(InventoryType.ENCHANTING)) {
+
+            return;
+
+        }
+
+        if (event.getRawSlots().contains(ENCHANTING_LAPIS_SLOT) || isLapis(event.getOldCursor())) {
+
+            event.setCancelled(true);
+
+        }
+
+        refillEnchantingTableNextTick(inventory);
+
     }
 
     @EventHandler
@@ -45,7 +103,7 @@ public class OldEnchantOG extends JavaPlugin implements Listener {
         Inventory inventory = event.getInventory();
         if (inventory.getType().equals(InventoryType.ENCHANTING)) {
 
-            inventory.setItem(1, null);
+            ((EnchantingInventory) inventory).setSecondary(null);
 
         }
 
@@ -59,6 +117,42 @@ public class OldEnchantOG extends JavaPlugin implements Listener {
 
         event.getEnchanter().setLevel(newLevel);
         event.setExpLevelCost(1);
+        ((EnchantingInventory) event.getInventory()).setSecondary(getLapis());
+
+    }
+
+    private void fillUpEnchantingTable(Inventory inventory) {
+
+        if (inventory == null || inventory.getType() != InventoryType.ENCHANTING) {
+
+            return;
+
+        }
+
+        EnchantingInventory enchantingInventory = (EnchantingInventory) inventory;
+        if (!isLapis(enchantingInventory.getSecondary()) || enchantingInventory.getSecondary().getAmount() != AUTO_LAPIS_AMOUNT) {
+
+            enchantingInventory.setSecondary(getLapis());
+
+        }
+
+    }
+
+    private void refillEnchantingTableNextTick(Inventory inventory) {
+
+        Bukkit.getScheduler().runTask(this, () -> fillUpEnchantingTable(inventory));
+
+    }
+
+    private ItemStack getLapis() {
+
+        return new ItemStack(Material.LAPIS_LAZULI, AUTO_LAPIS_AMOUNT);
+
+    }
+
+    private boolean isLapis(ItemStack item) {
+
+        return item != null && item.getType() == Material.LAPIS_LAZULI;
 
     }