Paper/nms-patches/EntityInsentient.patch

--- a/net/minecraft/server/EntityInsentient.java
+++ b/net/minecraft/server/EntityInsentient.java
@@ -8,6 +8,15 @@
 import java.util.Random;
 import java.util.UUID;
 
+// CraftBukkit start
+import org.bukkit.craftbukkit.event.CraftEventFactory;
+import org.bukkit.craftbukkit.entity.CraftLivingEntity;
+import org.bukkit.event.entity.EntityTargetLivingEntityEvent;
+import org.bukkit.event.entity.EntityTargetEvent;
+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> a = DataWatcher.a(EntityInsentient.class, DataWatcherRegistry.a);
@@ -60,6 +69,9 @@
             this.r();
         }
 
+        // CraftBukkit start - default persistance to type's persistance value
+        this.persistent = !isTypeNotPersistent();
+        // CraftBukkit end
     }
 
     protected void r() {}
@@ -110,7 +122,37 @@
     }
 
     public void setGoalTarget(EntityLiving entityliving) {
+        // CraftBukkit start - fire event
+        setGoalTarget(entityliving, EntityTargetEvent.TargetReason.UNKNOWN, true);
+    }
+
+    public void setGoalTarget(EntityLiving entityliving, EntityTargetEvent.TargetReason reason, boolean fireEvent) {
+        if (getGoalTarget() == entityliving) return;
+        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) {
+                world.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);
+            world.getServer().getPluginManager().callEvent(event);
+            if (event.isCancelled()) {
+                return;
+            }
+
+            if (event.getTarget() != null) {
+                entityliving = ((CraftLivingEntity) event.getTarget()).getHandle();
+            } else {
+                entityliving = null;
+            }
+        }
         this.goalTarget = entityliving;
+        // CraftBukkit end
     }
 
     public boolean d(Class<? extends EntityLiving> oclass) {
@@ -225,6 +267,7 @@
         return null;
     }
 
+    protected ItemStack headDrop = null; // CraftBukkit
     protected void dropDeathLoot(boolean flag, int i) {
         Item item = this.getLoot();
 
@@ -240,6 +283,12 @@
             }
         }
 
+        // CraftBukkit start
+        if (headDrop != null) {
+            this.a(headDrop, 0.0F);
+            headDrop = null;
+        }
+        // CraftBukkit end
     }
 
     public void b(NBTTagCompound nbttagcompound) {
@@ -321,11 +370,20 @@
 
     public void a(NBTTagCompound nbttagcompound) {
         super.a(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.l(nbttagcompound.getBoolean("CanPickUpLoot"));
+            boolean data = nbttagcompound.getBoolean("CanPickUpLoot");
+            if (isLevelAtLeast(nbttagcompound, 1) || data) {
+                this.l(data);
+            }
         }
 
-        this.persistent = nbttagcompound.getBoolean("PersistenceRequired");
+        boolean data = nbttagcompound.getBoolean("PersistenceRequired");
+        if (isLevelAtLeast(nbttagcompound, 1) || data) {
+            this.persistent = data;
+        }
+        // CraftBukkit end
         NBTTagList nbttaglist;
         int i;
 
@@ -549,11 +607,11 @@
                 double d2 = entityhuman.locZ - this.locZ;
                 double d3 = d0 * d0 + d1 * d1 + d2 * d2;
 
-                if (this.isTypeNotPersistent() && d3 > 16384.0D) {
+                if (d3 > 16384.0D) { // CraftBukkit - remove isTypeNotPersistent() check
                     this.die();
                 }
 
-                if (this.ticksFarFromPlayer > 600 && this.random.nextInt(800) == 0 && d3 > 1024.0D && this.isTypeNotPersistent()) {
+                if (this.ticksFarFromPlayer > 600 && this.random.nextInt(800) == 0 && d3 > 1024.0D) { // CraftBukkit - remove isTypeNotPersistent() check
                     this.die();
                 } else if (d3 < 1024.0D) {
                     this.ticksFarFromPlayer = 0;
@@ -931,9 +989,21 @@
 
     public final boolean a(EntityHuman entityhuman, ItemStack itemstack, EnumHand enumhand) {
         if (this.isLeashed() && this.getLeashHolder() == entityhuman) {
+            // CraftBukkit start - fire PlayerUnleashEntityEvent
+            if (CraftEventFactory.callPlayerUnleashEntityEvent(this, entityhuman).isCancelled()) {
+                ((EntityPlayer) entityhuman).playerConnection.sendPacket(new PacketPlayOutAttachEntity(this, this.getLeashHolder()));
+                return false;
+            }
+            // CraftBukkit end
             this.unleash(true, !entityhuman.abilities.canInstantlyBuild);
             return true;
         } else if (itemstack != null && itemstack.getItem() == Items.LEAD && this.a(entityhuman)) {
+            // CraftBukkit start - fire PlayerLeashEntityEvent
+            if (CraftEventFactory.callPlayerLeashEntityEvent(this, entityhuman, entityhuman).isCancelled()) {
+                ((EntityPlayer) entityhuman).playerConnection.sendPacket(new PacketPlayOutAttachEntity(this, this.getLeashHolder()));
+                return false;
+            }
+            // CraftBukkit end
             this.setLeashHolder(entityhuman, true);
             --itemstack.count;
             return true;
@@ -953,10 +1023,12 @@
 
         if (this.bC) {
             if (!this.isAlive()) {
+                this.world.getServer().getPluginManager().callEvent(new EntityUnleashEvent(this.getBukkitEntity(), UnleashReason.PLAYER_UNLEASH)); // CraftBukkit
                 this.unleash(true, true);
             }
 
             if (this.leashHolder == null || this.leashHolder.dead) {
+                this.world.getServer().getPluginManager().callEvent(new EntityUnleashEvent(this.getBukkitEntity(), UnleashReason.HOLDER_GONE)); // CraftBukkit
                 this.unleash(true, true);
             }
         }
@@ -1037,6 +1109,7 @@
 
                 this.leashHolder = entityleash;
             } else {
+                this.world.getServer().getPluginManager().callEvent(new EntityUnleashEvent(this.getBukkitEntity(), UnleashReason.UNKNOWN)); // CraftBukkit
                 this.unleash(false, true);
             }
         }