PaperMC/Spigot-Server-Patches/0192-Ability-to-apply-mending-to-XP-API.patch

From d5fb0d436ef69748430a2bd4aefd7d74ccc57ff0 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Wed, 20 Dec 2017 17:36:49 -0500
Subject: [PATCH] Ability to apply mending to XP API

This allows plugins that give players the ability to apply the experience
points to the Item Mending formula, which will repair an item instead
of giving the player experience points.

Both an API To standalone mend, and apply mending logic to .giveExp has been added.

diff --git a/src/main/java/net/minecraft/server/EnchantmentManager.java b/src/main/java/net/minecraft/server/EnchantmentManager.java
index ed9aedc07..1d16919e6 100644
--- a/src/main/java/net/minecraft/server/EnchantmentManager.java
+++ b/src/main/java/net/minecraft/server/EnchantmentManager.java
@@ -241,6 +241,11 @@ public class EnchantmentManager {
         return getEnchantmentLevel(Enchantments.CHANNELING, itemstack) > 0;
     }
 
+    // Paper - OBFHELPER
+    public static @Nullable ItemStack getRandomEquippedItemWithEnchant(Enchantment enchantment, EntityLiving entityliving) {
+        Entry<EnumItemSlot, ItemStack> entry = b(enchantment, entityliving);
+        return entry != null ? entry.getValue() : null;
+    }
     @Nullable
     public static Entry<EnumItemSlot, ItemStack> b(Enchantment enchantment, EntityLiving entityliving) {
         Map<EnumItemSlot, ItemStack> map = enchantment.a(entityliving);
diff --git a/src/main/java/net/minecraft/server/EntityExperienceOrb.java b/src/main/java/net/minecraft/server/EntityExperienceOrb.java
index e6b810756..ba3e66f9e 100644
--- a/src/main/java/net/minecraft/server/EntityExperienceOrb.java
+++ b/src/main/java/net/minecraft/server/EntityExperienceOrb.java
@@ -254,10 +254,12 @@ public class EntityExperienceOrb extends Entity {
         }
     }
 
+    public int durToXp(int i) { return b(i); } // Paper OBFHELPER
     private int b(int i) {
         return i / 2;
     }
 
+    public int xpToDur(int i) { return c(i); } // Paper OBFHELPER
     private int c(int i) {
         return i * 2;
     }
diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
index 3e8979dfe..a1481c5b8 100644
--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
+++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
@@ -1063,8 +1063,39 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
         return GameMode.getByValue(getHandle().playerInteractManager.getGameMode().getId());
     }
 
+    // Paper start
     @Override
-    public void giveExp(int exp) {
+    public int applyMending(int amount) {
+        EntityPlayer handle = getHandle();
+        // Logic copied from EntityExperienceOrb and remapped to unobfuscated methods/properties
+        net.minecraft.server.ItemStack itemstack = net.minecraft.server.EnchantmentManager.getRandomEquippedItemWithEnchant(net.minecraft.server.Enchantments.MENDING, handle);
+        if (!itemstack.isEmpty() && itemstack.getItem().usesDurability()) {
+
+            net.minecraft.server.EntityExperienceOrb orb = net.minecraft.server.EntityTypes.EXPERIENCE_ORB.create(handle.world);
+            orb.value = amount;
+            orb.spawnReason = org.bukkit.entity.ExperienceOrb.SpawnReason.CUSTOM;
+            orb.locX = handle.locX;
+            orb.locY = handle.locY;
+            orb.locZ = handle.locZ;
+
+            int i = Math.min(orb.xpToDur(amount), itemstack.getDamage());
+            org.bukkit.event.player.PlayerItemMendEvent event = org.bukkit.craftbukkit.event.CraftEventFactory.callPlayerItemMendEvent(handle, orb, itemstack, i);
+            i = event.getRepairAmount();
+            orb.dead = true;
+            if (!event.isCancelled()) {
+                amount -= orb.durToXp(i);
+                itemstack.setDamage(itemstack.getDamage() - i);
+            }
+        }
+        return amount;
+    }
+
+    @Override
+    public void giveExp(int exp, boolean applyMending) {
+        if (applyMending) {
+            exp = this.applyMending(exp);
+        }
+        // Paper end
         getHandle().giveExp(exp);
     }
 
-- 
2.23.0