From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Jake Potrebic <jake.m.potrebic@gmail.com>
Date: Sun, 8 May 2022 13:35:45 -0700
Subject: [PATCH] ItemStack damage API

Adds methods notify clients about item breaks and
to simulate damage done to an itemstack and all
the logic associated with damaging them

== AT ==
public net.minecraft.world.entity.LivingEntity entityEventForEquipmentBreak(Lnet/minecraft/world/entity/EquipmentSlot;)B

diff --git a/src/main/java/net/minecraft/world/item/ItemStack.java b/src/main/java/net/minecraft/world/item/ItemStack.java
index bee59df6a8f30416f94c1a4fbd5e2629336e842f..e64cc91b416bbbefe6aadf1c6b685346cf258ab4 100644
--- a/src/main/java/net/minecraft/world/item/ItemStack.java
+++ b/src/main/java/net/minecraft/world/item/ItemStack.java
@@ -647,8 +647,13 @@ public final class ItemStack implements DataComponentHolder {
     }
 
     public void hurtAndBreak(int amount, ServerLevel world, @Nullable LivingEntity player, Consumer<Item> breakCallback) { // Paper - Add EntityDamageItemEvent
+        // Paper start - add param to skip infinite mats check
+        this.hurtAndBreak(amount, world, player, breakCallback, false);
+    }
+    public void hurtAndBreak(int amount, ServerLevel world, @Nullable LivingEntity player, Consumer<Item> breakCallback, boolean force) {
+        // Paper end - add param to skip infinite mats check
         if (this.isDamageableItem()) {
-            if (player == null || !player.hasInfiniteMaterials()) {
+            if (player == null || !player.hasInfiniteMaterials() || force) { // Paper
                 if (amount > 0) {
                     int originalDamage = amount; // Paper - Expand PlayerItemDamageEvent
                     amount = EnchantmentHelper.processDurabilityChange(world, this, amount);
@@ -704,6 +709,11 @@ public final class ItemStack implements DataComponentHolder {
     }
 
     public void hurtAndBreak(int amount, LivingEntity entity, EquipmentSlot slot) {
+        // Paper start - add param to skip infinite mats check
+        this.hurtAndBreak(amount, entity, slot, false);
+    }
+    public void hurtAndBreak(int amount, LivingEntity entity, EquipmentSlot slot, boolean force) {
+        // Paper end - add param to skip infinite mats check
         Level world = entity.level();
 
         if (world instanceof ServerLevel worldserver) {
@@ -716,8 +726,8 @@ public final class ItemStack implements DataComponentHolder {
             }
 
             this.hurtAndBreak(amount, worldserver, entity, (item) -> { // Paper - Add EntityDamageItemEvent
-                entity.onEquippedItemBroken(item, slot);
-            });
+                if (slot != null) entity.onEquippedItemBroken(item, slot); // Paper - itemstack damage API - do not process entity related callbacks when damaging from API
+            }, force); // Paper - itemstack damage API
         }
 
     }
diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftLivingEntity.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftLivingEntity.java
index 8babdfe0c6bd921f95cf55313197d576035b0891..f1d2a1610649779da09a76ede7fdfa14658c82ba 100644
--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftLivingEntity.java
+++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftLivingEntity.java
@@ -1117,4 +1117,48 @@ public class CraftLivingEntity extends CraftEntity implements LivingEntity {
         this.getHandle().knockback(strength, directionX, directionZ);
     };
     // Paper end - knockback API
+
+    // Paper start - ItemStack damage API
+    public void broadcastSlotBreak(final org.bukkit.inventory.EquipmentSlot slot) {
+        this.getHandle().level().broadcastEntityEvent(this.getHandle(), net.minecraft.world.entity.LivingEntity.entityEventForEquipmentBreak(org.bukkit.craftbukkit.CraftEquipmentSlot.getNMS(slot)));
+    }
+
+    @Override
+    public void broadcastSlotBreak(final org.bukkit.inventory.EquipmentSlot slot, final Collection<org.bukkit.entity.Player> players) {
+        if (players.isEmpty()) {
+            return;
+        }
+        final net.minecraft.network.protocol.game.ClientboundEntityEventPacket packet = new net.minecraft.network.protocol.game.ClientboundEntityEventPacket(
+            this.getHandle(),
+            net.minecraft.world.entity.LivingEntity.entityEventForEquipmentBreak(org.bukkit.craftbukkit.CraftEquipmentSlot.getNMS(slot))
+        );
+        players.forEach(player -> ((CraftPlayer) player).getHandle().connection.send(packet));
+    }
+
+    @Override
+    public ItemStack damageItemStack(ItemStack stack, final int amount) {
+        final net.minecraft.world.item.ItemStack nmsStack;
+        if (stack instanceof final CraftItemStack craftItemStack) {
+            if (craftItemStack.handle == null || craftItemStack.handle.isEmpty()) {
+                return stack;
+            }
+            nmsStack = craftItemStack.handle;
+        } else {
+            nmsStack = CraftItemStack.asNMSCopy(stack);
+            stack = CraftItemStack.asCraftMirror(nmsStack); // mirror to capture changes in hurt logic & events
+        }
+        this.damageItemStack0(nmsStack, amount, null);
+        return stack;
+    }
+
+    @Override
+    public void damageItemStack(final org.bukkit.inventory.EquipmentSlot slot, final int amount) {
+        final net.minecraft.world.entity.EquipmentSlot nmsSlot = org.bukkit.craftbukkit.CraftEquipmentSlot.getNMS(slot);
+        this.damageItemStack0(this.getHandle().getItemBySlot(nmsSlot), amount, nmsSlot);
+    }
+
+    private void damageItemStack0(final net.minecraft.world.item.ItemStack nmsStack, final int amount, final net.minecraft.world.entity.EquipmentSlot slot) {
+        nmsStack.hurtAndBreak(amount, this.getHandle(), slot, true);
+    }
+    // Paper end - ItemStack damage API
 }