Paper/paper-server/nms-patches/net/minecraft/world/entity/EntityInsentient.patch

--- a/net/minecraft/world/entity/EntityInsentient.java
+++ b/net/minecraft/world/entity/EntityInsentient.java
@@ -72,6 +72,19 @@
 import net.minecraft.world.level.pathfinder.PathType;
 import net.minecraft.world.level.storage.loot.LootTableInfo;
 
+// CraftBukkit start
+import net.minecraft.server.level.EntityPlayer;
+import org.bukkit.craftbukkit.event.CraftEventFactory;
+import org.bukkit.craftbukkit.entity.CraftLivingEntity;
+import org.bukkit.event.entity.CreatureSpawnEvent;
+import org.bukkit.event.entity.EntityCombustByEntityEvent;
+import org.bukkit.event.entity.EntityTargetLivingEntityEvent;
+import org.bukkit.event.entity.EntityTargetEvent;
+import org.bukkit.event.entity.EntityTransformEvent;
+import org.bukkit.event.entity.EntityUnleashEvent;
+import org.bukkit.event.entity.EntityUnleashEvent.UnleashReason;
+// CraftBukkit end
+
 public abstract class EntityInsentient extends EntityLiving {
 
     private static final DataWatcherObject<Byte> DATA_MOB_FLAGS_ID = DataWatcher.a(EntityInsentient.class, DataWatcherRegistry.BYTE);
@@ -112,6 +125,8 @@
     private BlockPosition restrictCenter;
     private float restrictRadius;
 
+    public boolean aware = true; // CraftBukkit
+
     protected EntityInsentient(EntityTypes<? extends EntityInsentient> entitytypes, World world) {
         super(entitytypes, world);
         this.handItems = NonNullList.a(2, ItemStack.EMPTY);
@@ -135,6 +150,9 @@
             this.initPathfinder();
         }
 
+        // CraftBukkit start - default persistance to type's persistance value
+        this.persistenceRequired = !isTypeNotPersistent(0);
+        // CraftBukkit end
     }
 
     protected void initPathfinder() {}
@@ -215,7 +233,38 @@
     }
 
     public void setGoalTarget(@Nullable EntityLiving entityliving) {
+        // CraftBukkit start - fire event
+        setGoalTarget(entityliving, EntityTargetEvent.TargetReason.UNKNOWN, true);
+    }
+
+    public boolean setGoalTarget(EntityLiving entityliving, EntityTargetEvent.TargetReason reason, boolean fireEvent) {
+        if (getGoalTarget() == entityliving) return false;
+        if (fireEvent) {
+            if (reason == EntityTargetEvent.TargetReason.UNKNOWN && getGoalTarget() != null && entityliving == null) {
+                reason = getGoalTarget().isAlive() ? EntityTargetEvent.TargetReason.FORGOT_TARGET : EntityTargetEvent.TargetReason.TARGET_DIED;
+            }
+            if (reason == EntityTargetEvent.TargetReason.UNKNOWN) {
+                level.getServer().getLogger().log(java.util.logging.Level.WARNING, "Unknown target reason, please report on the issue tracker", new Exception());
+            }
+            CraftLivingEntity ctarget = null;
+            if (entityliving != null) {
+                ctarget = (CraftLivingEntity) entityliving.getBukkitEntity();
+            }
+            EntityTargetLivingEntityEvent event = new EntityTargetLivingEntityEvent(this.getBukkitEntity(), ctarget, reason);
+            level.getServer().getPluginManager().callEvent(event);
+            if (event.isCancelled()) {
+                return false;
+            }
+
+            if (event.getTarget() != null) {
+                entityliving = ((CraftLivingEntity) event.getTarget()).getHandle();
+            } else {
+                entityliving = null;
+            }
+        }
         this.target = entityliving;
+        return true;
+        // CraftBukkit end
     }
 
     @Override
@@ -442,16 +491,26 @@
             nbttagcompound.setBoolean("NoAI", this.isNoAI());
         }
 
+        nbttagcompound.setBoolean("Bukkit.Aware", this.aware); // CraftBukkit
     }
 
     @Override
     public void loadData(NBTTagCompound nbttagcompound) {
         super.loadData(nbttagcompound);
+
+        // CraftBukkit start - If looting or persistence is false only use it if it was set after we started using it
         if (nbttagcompound.hasKeyOfType("CanPickUpLoot", 1)) {
-            this.setCanPickupLoot(nbttagcompound.getBoolean("CanPickUpLoot"));
+            boolean data = nbttagcompound.getBoolean("CanPickUpLoot");
+            if (isLevelAtLeast(nbttagcompound, 1) || data) {
+                this.setCanPickupLoot(data);
+            }
         }
 
-        this.persistenceRequired = nbttagcompound.getBoolean("PersistenceRequired");
+        boolean data = nbttagcompound.getBoolean("PersistenceRequired");
+        if (isLevelAtLeast(nbttagcompound, 1) || data) {
+            this.persistenceRequired = data;
+        }
+        // CraftBukkit end
         NBTTagList nbttaglist;
         int i;
 
@@ -498,6 +557,11 @@
         }
 
         this.setNoAI(nbttagcompound.getBoolean("NoAI"));
+        // CraftBukkit start
+        if (nbttagcompound.hasKey("Bukkit.Aware")) {
+            this.aware = nbttagcompound.getBoolean("Bukkit.Aware");
+        }
+        // CraftBukkit end
     }
 
     @Override
@@ -561,7 +625,7 @@
     protected void b(EntityItem entityitem) {
         ItemStack itemstack = entityitem.getItemStack();
 
-        if (this.j(itemstack)) {
+        if (this.j(itemstack, entityitem)) { // CraftBukkit - add item
             this.a(entityitem);
             this.receive(entityitem, itemstack.getCount());
             entityitem.die();
@@ -570,15 +634,29 @@
     }
 
     public boolean j(ItemStack itemstack) {
+        // CraftBukkit start - add item
+        return this.j(itemstack, null);
+    }
+
+    public boolean j(ItemStack itemstack, EntityItem entityitem) {
+        // CraftBukkit end
         EnumItemSlot enumitemslot = getEquipmentSlotForItem(itemstack);
         ItemStack itemstack1 = this.getEquipment(enumitemslot);
         boolean flag = this.a(itemstack, itemstack1);
 
-        if (flag && this.canPickup(itemstack)) {
+        // CraftBukkit start
+        boolean canPickup = flag && this.canPickup(itemstack);
+        if (entityitem != null) {
+            canPickup = !org.bukkit.craftbukkit.event.CraftEventFactory.callEntityPickupItemEvent(this, entityitem, 0, !canPickup).isCancelled();
+        }
+        if (canPickup) {
+            // CraftBukkit end
             double d0 = (double) this.e(enumitemslot);
 
             if (!itemstack1.isEmpty() && (double) Math.max(this.random.nextFloat() - 0.1F, 0.0F) < d0) {
+                this.forceDrops = true; // CraftBukkit
                 this.b(itemstack1);
+                this.forceDrops = false; // CraftBukkit
             }
 
             this.b(enumitemslot, itemstack);
@@ -691,18 +769,18 @@
             EntityHuman entityhuman = this.level.findNearbyPlayer(this, -1.0D);
 
             if (entityhuman != null) {
-                double d0 = entityhuman.f(this);
+                double d0 = entityhuman.f((Entity) this); // CraftBukkit - decompile error
                 int i = this.getEntityType().f().f();
                 int j = i * i;
 
-                if (d0 > (double) j && this.isTypeNotPersistent(d0)) {
+                if (d0 > (double) j) { // CraftBukkit - remove isTypeNotPersistent() check
                     this.die();
                 }
 
                 int k = this.getEntityType().f().g();
                 int l = k * k;
 
-                if (this.noActionTime > 600 && this.random.nextInt(800) == 0 && d0 > (double) l && this.isTypeNotPersistent(d0)) {
+                if (this.noActionTime > 600 && this.random.nextInt(800) == 0 && d0 > (double) l) { // CraftBukkit - remove isTypeNotPersistent() check
                     this.die();
                 } else if (d0 < (double) l) {
                     this.noActionTime = 0;
@@ -717,6 +795,7 @@
     @Override
     protected final void doTick() {
         ++this.noActionTime;
+        if (!this.aware) return; // CraftBukkit
         this.level.getMethodProfiler().enter("sensing");
         this.sensing.a();
         this.level.getMethodProfiler().exit();
@@ -1100,6 +1179,12 @@
         if (!this.isAlive()) {
             return EnumInteractionResult.PASS;
         } else if (this.getLeashHolder() == entityhuman) {
+            // CraftBukkit start - fire PlayerUnleashEntityEvent
+            if (CraftEventFactory.callPlayerUnleashEntityEvent(this, entityhuman).isCancelled()) {
+                ((EntityPlayer) entityhuman).connection.sendPacket(new PacketPlayOutAttachEntity(this, this.getLeashHolder()));
+                return EnumInteractionResult.PASS;
+            }
+            // CraftBukkit end
             this.unleash(true, !entityhuman.getAbilities().instabuild);
             return EnumInteractionResult.a(this.level.isClientSide);
         } else {
@@ -1118,6 +1203,12 @@
         ItemStack itemstack = entityhuman.b(enumhand);
 
         if (itemstack.a(Items.LEAD) && this.a(entityhuman)) {
+            // CraftBukkit start - fire PlayerLeashEntityEvent
+            if (CraftEventFactory.callPlayerLeashEntityEvent(this, entityhuman, entityhuman).isCancelled()) {
+                ((EntityPlayer) entityhuman).connection.sendPacket(new PacketPlayOutAttachEntity(this, this.getLeashHolder()));
+                return EnumInteractionResult.PASS;
+            }
+            // CraftBukkit end
             this.setLeashHolder(entityhuman, true);
             itemstack.subtract(1);
             return EnumInteractionResult.a(this.level.isClientSide);
@@ -1133,7 +1224,7 @@
             if (itemstack.getItem() instanceof ItemMonsterEgg) {
                 if (this.level instanceof WorldServer) {
                     ItemMonsterEgg itemmonsteregg = (ItemMonsterEgg) itemstack.getItem();
-                    Optional<EntityInsentient> optional = itemmonsteregg.a(entityhuman, this, this.getEntityType(), (WorldServer) this.level, this.getPositionVector(), itemstack);
+                    Optional<EntityInsentient> optional = itemmonsteregg.a(entityhuman, this, (EntityTypes<? extends EntityInsentient>) this.getEntityType(), (WorldServer) this.level, this.getPositionVector(), itemstack); // CraftBukkit - decompile error
 
                     optional.ifPresent((entityinsentient) -> {
                         this.a(entityhuman, entityinsentient);
@@ -1183,12 +1274,19 @@
         return this.restrictRadius != -1.0F;
     }
 
+    // CraftBukkit start
     @Nullable
     public <T extends EntityInsentient> T a(EntityTypes<T> entitytypes, boolean flag) {
+        return this.a(entitytypes, flag, EntityTransformEvent.TransformReason.UNKNOWN, CreatureSpawnEvent.SpawnReason.DEFAULT);
+    }
+
+    @Nullable
+    public <T extends EntityInsentient> T a(EntityTypes<T> entitytypes, boolean flag, EntityTransformEvent.TransformReason transformReason, CreatureSpawnEvent.SpawnReason spawnReason) {
+        // CraftBukkit end
         if (this.isRemoved()) {
             return null;
         } else {
-            T t0 = (EntityInsentient) entitytypes.a(this.level);
+            T t0 = entitytypes.a(this.level); // CraftBukkit - decompile error
 
             t0.s(this);
             t0.setBaby(this.isBaby());
@@ -1220,7 +1318,12 @@
                 }
             }
 
-            this.level.addEntity(t0);
+            // CraftBukkit start
+            if (CraftEventFactory.callEntityTransformEvent(this, t0, transformReason).isCancelled()) {
+                return null;
+            }
+            this.level.addEntity(t0, spawnReason);
+            // CraftBukkit end
             if (this.isPassenger()) {
                 Entity entity = this.getVehicle();
 
@@ -1240,6 +1343,7 @@
 
         if (this.leashHolder != null) {
             if (!this.isAlive() || !this.leashHolder.isAlive()) {
+                this.level.getServer().getPluginManager().callEvent(new EntityUnleashEvent(this.getBukkitEntity(), (!this.isAlive()) ? UnleashReason.PLAYER_UNLEASH : UnleashReason.HOLDER_GONE)); // CraftBukkit
                 this.unleash(true, true);
             }
 
@@ -1251,7 +1355,9 @@
             this.leashHolder = null;
             this.leashInfoTag = null;
             if (!this.level.isClientSide && flag1) {
+                this.forceDrops = true; // CraftBukkit
                 this.a((IMaterial) Items.LEAD);
+                this.forceDrops = false; // CraftBukkit
             }
 
             if (!this.level.isClientSide && flag && this.level instanceof WorldServer) {
@@ -1301,6 +1407,7 @@
         boolean flag1 = super.a(entity, flag);
 
         if (flag1 && this.isLeashed()) {
+            this.level.getServer().getPluginManager().callEvent(new EntityUnleashEvent(this.getBukkitEntity(), UnleashReason.UNKNOWN)); // CraftBukkit
             this.unleash(true, true);
         }
 
@@ -1396,7 +1503,14 @@
         int i = EnchantmentManager.getFireAspectEnchantmentLevel(this);
 
         if (i > 0) {
-            entity.setOnFire(i * 4);
+            // CraftBukkit start - Call a combust event when somebody hits with a fire enchanted item
+            EntityCombustByEntityEvent combustEvent = new EntityCombustByEntityEvent(this.getBukkitEntity(), entity.getBukkitEntity(), i * 4);
+            org.bukkit.Bukkit.getPluginManager().callEvent(combustEvent);
+
+            if (!combustEvent.isCancelled()) {
+                entity.setOnFire(combustEvent.getDuration(), false);
+            }
+            // CraftBukkit end
         }
 
         boolean flag = entity.damageEntity(DamageSource.mobAttack(this), f);
@@ -1464,9 +1578,10 @@
     @Override
     protected void cc() {
         super.cc();
+        this.level.getServer().getPluginManager().callEvent(new EntityUnleashEvent(this.getBukkitEntity(), UnleashReason.UNKNOWN)); // CraftBukkit
         this.unleash(true, false);
         this.by().forEach((itemstack) -> {
-            itemstack.setCount(0);
+            if (!itemstack.isEmpty()) itemstack.setCount(0); // CraftBukkit
         });
     }