Add PlayerShieldDisableEvent

Called whenever a players shield is disabled. This is mainly caused by
attacking players or monsters that carry axes.

The event, while similar to the PlayerItemCooldownEvent, offers other
behaviour and can hence not be implemented as a childtype of said event.
Specifically, cancelling the event prevents the game events from being
sent to the player.

Plugins listening to just the PlayerItemCooldownEvent may not want said
sideeffects, meaning the disable event cannot share a handlerlist with
the cooldown event

paper-server/patches/sources/net/minecraft/world/entity/player/Player.java.patch

@@ -210,6 +210,15 @@
              }
          }
      }
+@@ -912,7 +973,7 @@
+         ItemStack itemstack = this.getItemBlockingWith();
+ 
+         if (attacker.canDisableShield() && itemstack != null) {
+-            this.disableShield(itemstack);
++            this.disableShield(itemstack, attacker); // Paper - Add PlayerShieldDisableEvent
+         }
+ 
+     }
 @@ -923,10 +984,29 @@
      }
  
@@ -475,7 +484,30 @@
                      }
                  }
  
-@@ -1351,7 +1490,14 @@
+@@ -1327,8 +1466,21 @@
+         this.attack(target);
+     }
+ 
++    @io.papermc.paper.annotation.DoNotUse @Deprecated // Paper - Add PlayerShieldDisableEvent
+     public void disableShield(ItemStack shield) {
+-        this.getCooldowns().addCooldown(shield, 100);
++        // Paper start - Add PlayerShieldDisableEvent
++        this.disableShield(shield, null);
++    }
++    public void disableShield(ItemStack shield, @Nullable LivingEntity attacker) {
++        final org.bukkit.entity.Entity finalAttacker = attacker != null ? attacker.getBukkitEntity() : null;
++        if (finalAttacker != null) {
++            final io.papermc.paper.event.player.PlayerShieldDisableEvent shieldDisableEvent = new io.papermc.paper.event.player.PlayerShieldDisableEvent((org.bukkit.entity.Player) getBukkitEntity(), finalAttacker, 100);
++            if (!shieldDisableEvent.callEvent()) return;
++            this.getCooldowns().addCooldown(shield, shieldDisableEvent.getCooldown());
++        } else {
++            this.getCooldowns().addCooldown(shield, 100);
++        }
++        // Paper end - Add PlayerShieldDisableEvent
+         this.stopUsingItem();
+         this.level().broadcastEntityEvent(this, (byte) 30);
+     }
+@@ -1351,7 +1503,14 @@
  
      @Override
      public void remove(Entity.RemovalReason reason) {
@@ -491,7 +523,7 @@
          this.inventoryMenu.removed(this);
          if (this.containerMenu != null && this.hasContainerOpen()) {
              this.doCloseContainer();
-@@ -1391,7 +1537,13 @@
+@@ -1391,7 +1550,13 @@
      }
  
      public Either<Player.BedSleepingProblem, Unit> startSleepInBed(BlockPos pos) {
@@ -506,7 +538,7 @@
          this.sleepCounter = 0;
          return Either.right(Unit.INSTANCE);
      }
-@@ -1503,7 +1655,7 @@
+@@ -1503,7 +1668,7 @@
  
      @Override
      public boolean causeFallDamage(float fallDistance, float damageMultiplier, DamageSource damageSource) {
@@ -515,7 +547,7 @@
              return false;
          } else {
              if (fallDistance >= 2.0F) {
-@@ -1545,12 +1697,24 @@
+@@ -1545,12 +1710,24 @@
      }
  
      public void startFallFlying() {
@@ -541,20 +573,20 @@
      }
  
      @Override
-@@ -1662,13 +1826,32 @@
+@@ -1662,13 +1839,32 @@
      }
  
      public int getXpNeededForNextLevel() {
 -        return this.experienceLevel >= 30 ? 112 + (this.experienceLevel - 30) * 9 : (this.experienceLevel >= 15 ? 37 + (this.experienceLevel - 15) * 5 : 7 + this.experienceLevel * 2);
 +        return this.experienceLevel >= 30 ? 112 + (this.experienceLevel - 30) * 9 : (this.experienceLevel >= 15 ? 37 + (this.experienceLevel - 15) * 5 : 7 + this.experienceLevel * 2); // Paper - diff on change; calculateTotalExperiencePoints
-     }
++    }
 +    // Paper start - send while respecting visibility
 +    private static void sendSoundEffect(Player fromEntity, double x, double y, double z, SoundEvent soundEffect, SoundSource soundCategory, float volume, float pitch) {
 +        fromEntity.level().playSound(fromEntity, x, y, z, soundEffect, soundCategory, volume, pitch); // This will not send the effect to the entity itself
 +        if (fromEntity instanceof ServerPlayer serverPlayer) {
 +            serverPlayer.connection.send(new net.minecraft.network.protocol.game.ClientboundSoundPacket(net.minecraft.core.registries.BuiltInRegistries.SOUND_EVENT.wrapAsHolder(soundEffect), soundCategory, x, y, z, volume, pitch, fromEntity.random.nextLong()));
 +        }
-+    }
+     }
 +    // Paper end - send while respecting visibility
  
 +    // CraftBukkit start
@@ -576,7 +608,7 @@
              }
  
          }
-@@ -1748,13 +1931,20 @@
+@@ -1748,13 +1944,20 @@
  
      @Override
      public void setItemSlot(EquipmentSlot slot, ItemStack stack) {
@@ -604,7 +636,7 @@
          }
  
      }
-@@ -1798,26 +1988,55 @@
+@@ -1798,26 +2001,55 @@
  
      public void removeEntitiesOnShoulder() {
          if (this.timeEntitySatOnShoulder + 20L < this.level().getGameTime()) {
@@ -667,10 +699,12 @@
      }
  
      @Override
-@@ -2005,18 +2224,29 @@
+@@ -2003,20 +2235,31 @@
+     @Override
+     public ImmutableList<Pose> getDismountPoses() {
          return ImmutableList.of(Pose.STANDING, Pose.CROUCHING, Pose.SWIMMING);
-     }
++    }
- 
++
 +    // Paper start - PlayerReadyArrowEvent
 +    protected boolean tryReadyArrow(ItemStack bow, ItemStack itemstack) {
 +        return !(this instanceof ServerPlayer) ||
@@ -679,9 +713,9 @@
 +                    org.bukkit.craftbukkit.inventory.CraftItemStack.asCraftMirror(bow),
 +                    org.bukkit.craftbukkit.inventory.CraftItemStack.asCraftMirror(itemstack)
 +                ).callEvent();
-+    }
+     }
 +    // Paper end - PlayerReadyArrowEvent
-+
+ 
      @Override
      public ItemStack getProjectile(ItemStack stack) {
          if (!(stack.getItem() instanceof ProjectileWeaponItem)) {