Fix item enchanting pre-1.14 (#2127)

If the server spams the window property update packet, then the network ID assigned for each enchanting slot will update too quickly, essentially disabling enchanting. This commit remedies this by only updating the network ID of each slot if a property changed.

connector/src/main/java/org/geysermc/connector/inventory/GeyserEnchantOption.java

@@ -28,7 +28,6 @@ package org.geysermc.connector.inventory;
 import com.nukkitx.protocol.bedrock.data.inventory.EnchantData;
 import com.nukkitx.protocol.bedrock.data.inventory.EnchantOptionData;
 import lombok.Getter;
-import lombok.Setter;
 import org.geysermc.connector.network.session.GeyserSession;
 
 import java.util.Arrays;
@@ -38,7 +37,6 @@ import java.util.List;
 /**
  * A mutable "wrapper" around {@link EnchantOptionData}
  */
-@Setter
 public class GeyserEnchantOption {
     private static final List<EnchantData> EMPTY = Collections.emptyList();
     /**
@@ -57,6 +55,12 @@ public class GeyserEnchantOption {
     @Getter
     private final int javaIndex;
 
+    /**
+     * Whether the enchantment details have actually changed.
+     * Used to mitigate weird packet spamming pre-1.14, causing the net ID to always update.
+     */
+    private boolean hasChanged;
+
     private int xpCost = 0;
     private int javaEnchantIndex = -1;
     private int bedrockEnchantIndex = -1;
@@ -67,8 +71,35 @@ public class GeyserEnchantOption {
     }
 
     public EnchantOptionData build(GeyserSession session) {
+        this.hasChanged = false;
         return new EnchantOptionData(xpCost, javaIndex + 16, EMPTY,
                 enchantLevel == -1 ? EMPTY : Collections.singletonList(new EnchantData(bedrockEnchantIndex, enchantLevel)), EMPTY,
                 javaEnchantIndex == -1 ? "unknown" : ENCHANT_NAMES.get(javaEnchantIndex), enchantLevel == -1 ? 0 : session.getNextItemNetId());
     }
+
+    public boolean hasChanged() {
+        return hasChanged;
+    }
+
+    public void setXpCost(int xpCost) {
+        if (this.xpCost != xpCost) {
+            hasChanged = true;
+            this.xpCost = xpCost;
+        }
+    }
+
+    public void setEnchantIndex(int javaEnchantIndex, int bedrockEnchantIndex) {
+        if (this.javaEnchantIndex != javaEnchantIndex) {
+            hasChanged = true;
+            this.javaEnchantIndex = javaEnchantIndex;
+            this.bedrockEnchantIndex = bedrockEnchantIndex;
+        }
+    }
+
+    public void setEnchantLevel(int enchantLevel) {
+        if (this.enchantLevel != enchantLevel) {
+            hasChanged = true;
+            this.enchantLevel = enchantLevel;
+        }
+    }
 }

connector/src/main/java/org/geysermc/connector/network/translators/inventory/translators/EnchantingInventoryTranslator.java

@@ -34,6 +34,7 @@ import com.nukkitx.protocol.bedrock.data.inventory.stackrequestactions.StackRequ
 import com.nukkitx.protocol.bedrock.packet.ItemStackResponsePacket;
 import com.nukkitx.protocol.bedrock.packet.PlayerEnchantOptionsPacket;
 import org.geysermc.connector.inventory.EnchantingContainer;
+import org.geysermc.connector.inventory.GeyserEnchantOption;
 import org.geysermc.connector.inventory.Inventory;
 import org.geysermc.connector.inventory.PlayerInventory;
 import org.geysermc.connector.network.session.GeyserSession;
@@ -67,18 +68,20 @@ public class EnchantingInventoryTranslator extends AbstractBlockInventoryTransla
             case 6:
                 // Enchantment type
                 slotToUpdate = key - 4;
-                int index = value;
+                // "value" here is the Java enchant ordinal, so that does not need to be changed
-                if (index != -1) {
+                // The Bedrock index might need changed, so let's look it up and see.
-                    Enchantment enchantment = Enchantment.getByJavaIdentifier("minecraft:" + JavaEnchantment.values()[index].name().toLowerCase());
+                int bedrockIndex = value;
+                if (bedrockIndex != -1) {
+                    Enchantment enchantment = Enchantment.getByJavaIdentifier("minecraft:" + JavaEnchantment.values()[bedrockIndex].name().toLowerCase());
                     if (enchantment != null) {
                         // Convert the Java enchantment index to Bedrock's
-                        index = enchantment.ordinal();
+                        bedrockIndex = enchantment.ordinal();
                     } else {
-                        index = -1;
+                        // There is no Bedrock enchantment equivalent
+                        bedrockIndex = -1;
                     }
                 }
-                enchantingInventory.getGeyserEnchantOptions()[slotToUpdate].setJavaEnchantIndex(value);
+                enchantingInventory.getGeyserEnchantOptions()[slotToUpdate].setEnchantIndex(value, bedrockIndex);
-                enchantingInventory.getGeyserEnchantOptions()[slotToUpdate].setBedrockEnchantIndex(index);
                 break;
             case 7:
             case 8:
@@ -91,8 +94,9 @@ public class EnchantingInventoryTranslator extends AbstractBlockInventoryTransla
             default:
                 return;
         }
-        if (shouldUpdate) {
+        GeyserEnchantOption enchantOption = enchantingInventory.getGeyserEnchantOptions()[slotToUpdate];
-            enchantingInventory.getEnchantOptions()[slotToUpdate] = enchantingInventory.getGeyserEnchantOptions()[slotToUpdate].build(session);
+        if (shouldUpdate && enchantOption.hasChanged()) {
+            enchantingInventory.getEnchantOptions()[slotToUpdate] = enchantOption.build(session);
             PlayerEnchantOptionsPacket packet = new PlayerEnchantOptionsPacket();
             packet.getOptions().addAll(Arrays.asList(enchantingInventory.getEnchantOptions()));
             session.sendUpstreamPacket(packet);