Paper/patches/server/0287-Entity-getEntitySpawnReason.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Sun, 24 Mar 2019 00:24:52 -0400
Subject: [PATCH] Entity#getEntitySpawnReason

Allows you to return the SpawnReason for why an Entity Spawned

Pre existing entities will return NATURAL if it was a non
persistenting Living Entity, SPAWNER for spawners,
or DEFAULT since data was not stored.

diff --git a/src/main/java/net/minecraft/server/commands/SummonCommand.java b/src/main/java/net/minecraft/server/commands/SummonCommand.java
index 2eddeb8d5239bbfeefbf4d3bd363f1ad083299b6..e2b44b8ddb8afc6e1f7dddadb434c2268f284809 100644
--- a/src/main/java/net/minecraft/server/commands/SummonCommand.java
+++ b/src/main/java/net/minecraft/server/commands/SummonCommand.java
@@ -57,6 +57,7 @@ public class SummonCommand {
             ServerLevel worldserver = source.getLevel();
             Entity entity = EntityType.loadEntityRecursive(nbttagcompound1, worldserver, (entity1) -> {
                 entity1.moveTo(pos.x, pos.y, pos.z, entity1.getYRot(), entity1.getXRot());
+                entity1.spawnReason = org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.COMMAND; // Paper - Entity#getEntitySpawnReason
                 return entity1;
             });
 
diff --git a/src/main/java/net/minecraft/server/level/ServerLevel.java b/src/main/java/net/minecraft/server/level/ServerLevel.java
index 0811a2e87192b46c39f54c26ce0e56fc6e9d87e5..57f129651778d6c20c695bf7b3a8b4d40c402a20 100644
--- a/src/main/java/net/minecraft/server/level/ServerLevel.java
+++ b/src/main/java/net/minecraft/server/level/ServerLevel.java
@@ -1203,6 +1203,7 @@ public class ServerLevel extends Level implements WorldGenLevel {
             return true;
         }
         // Paper end - extra debug info
+        if (entity.spawnReason == null) entity.spawnReason = spawnReason; // Paper - Entity#getEntitySpawnReason
         if (entity.isRemoved()) {
             // WorldServer.LOGGER.warn("Tried to add entity {} but it was marked as removed already", EntityTypes.getKey(entity.getType())); // CraftBukkit
             return false;
diff --git a/src/main/java/net/minecraft/server/players/PlayerList.java b/src/main/java/net/minecraft/server/players/PlayerList.java
index 28b81e29be07902ad4d04aeb18bffd49757c3029..bc440f9a239d3935bf6837edf815d4fdc6093655 100644
--- a/src/main/java/net/minecraft/server/players/PlayerList.java
+++ b/src/main/java/net/minecraft/server/players/PlayerList.java
@@ -224,6 +224,11 @@ public abstract class PlayerList {
             worldserver1 = worldserver;
         }
 
+        // Paper start - Entity#getEntitySpawnReason
+        if (nbttagcompound == null) {
+            player.spawnReason = org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.DEFAULT; // set Player SpawnReason to DEFAULT on first login
+        }
+        // Paper end - Entity#getEntitySpawnReason
         player.setServerLevel(worldserver1);
         String s1 = connection.getLoggableAddress(this.server.logIPs());
 
@@ -355,7 +360,7 @@ public abstract class PlayerList {
             // CraftBukkit start
             ServerLevel finalWorldServer = worldserver1;
             Entity entity = EntityType.loadEntityRecursive(nbttagcompound1.getCompound("Entity"), finalWorldServer, (entity1) -> {
-                return !finalWorldServer.addWithUUID(entity1) ? null : entity1;
+                return !finalWorldServer.addWithUUID(entity1, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.MOUNT) ? null : entity1; // Paper - Entity#getEntitySpawnReason
                 // CraftBukkit end
             });
 
diff --git a/src/main/java/net/minecraft/world/entity/Entity.java b/src/main/java/net/minecraft/world/entity/Entity.java
index f746829f1e94ee58821e56ec4192269add00395b..257be4dd3f38c089dd970b9ac6f292b4f010a01c 100644
--- a/src/main/java/net/minecraft/world/entity/Entity.java
+++ b/src/main/java/net/minecraft/world/entity/Entity.java
@@ -238,6 +238,7 @@ public abstract class Entity implements Nameable, EntityAccess, CommandSource, S
         }
     }
     // Paper end - Share random for entities to make them more random
+    public org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason spawnReason; // Paper - Entity#getEntitySpawnReason
 
     public com.destroystokyo.paper.loottable.PaperLootableInventoryData lootableData; // Paper
     private CraftEntity bukkitEntity;
@@ -2178,6 +2179,9 @@ public abstract class Entity implements Nameable, EntityAccess, CommandSource, S
                 }
                 nbttagcompound.put("Paper.Origin", this.newDoubleList(origin.getX(), origin.getY(), origin.getZ()));
             }
+            if (spawnReason != null) {
+                nbttagcompound.putString("Paper.SpawnReason", spawnReason.name());
+            }
             // Save entity's from mob spawner status
             if (spawnedViaMobSpawner) {
                 nbttagcompound.putBoolean("Paper.FromMobSpawner", true);
@@ -2324,6 +2328,26 @@ public abstract class Entity implements Nameable, EntityAccess, CommandSource, S
             }
 
             spawnedViaMobSpawner = nbt.getBoolean("Paper.FromMobSpawner"); // Restore entity's from mob spawner status
+            if (nbt.contains("Paper.SpawnReason")) {
+                String spawnReasonName = nbt.getString("Paper.SpawnReason");
+                try {
+                    spawnReason = org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.valueOf(spawnReasonName);
+                } catch (Exception ignored) {
+                    LOGGER.error("Unknown SpawnReason " + spawnReasonName + " for " + this);
+                }
+            }
+            if (spawnReason == null) {
+                if (spawnedViaMobSpawner) {
+                    spawnReason = org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.SPAWNER;
+                } else if (this instanceof Mob && (this instanceof net.minecraft.world.entity.animal.Animal || this instanceof net.minecraft.world.entity.animal.AbstractFish) && !((Mob) this).removeWhenFarAway(0.0)) {
+                    if (!nbt.getBoolean("PersistenceRequired")) {
+                        spawnReason = org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.NATURAL;
+                    }
+                }
+            }
+            if (spawnReason == null) {
+                spawnReason = org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.DEFAULT;
+            }
             // Paper end
 
         } catch (Throwable throwable) {
diff --git a/src/main/java/net/minecraft/world/level/BaseSpawner.java b/src/main/java/net/minecraft/world/level/BaseSpawner.java
index cae8c508972d771ad96228ace8a7e6cbc34d5489..3184f73ce799cc5202d2129be736e2fed9a3b8e3 100644
--- a/src/main/java/net/minecraft/world/level/BaseSpawner.java
+++ b/src/main/java/net/minecraft/world/level/BaseSpawner.java
@@ -182,6 +182,7 @@ public abstract class BaseSpawner {
                         }
 
                         entity.spawnedViaMobSpawner = true; // Paper
+                        entity.spawnReason = org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.SPAWNER; // Paper - Entity#getEntitySpawnReason
                         flag = true; // Paper
                         // CraftBukkit start
                         if (org.bukkit.craftbukkit.event.CraftEventFactory.callSpawnerSpawnEvent(entity, pos).isCancelled()) {
diff --git a/src/main/java/net/minecraft/world/level/block/entity/SculkShriekerBlockEntity.java b/src/main/java/net/minecraft/world/level/block/entity/SculkShriekerBlockEntity.java
index faad948f089575e4988d989790cc1dd13f8a79cd..e143f42e71ac774d49b75e6d85591aa1189ee210 100644
--- a/src/main/java/net/minecraft/world/level/block/entity/SculkShriekerBlockEntity.java
+++ b/src/main/java/net/minecraft/world/level/block/entity/SculkShriekerBlockEntity.java
@@ -186,7 +186,7 @@ public class SculkShriekerBlockEntity extends BlockEntity implements GameEventLi
     }
 
     private boolean trySummonWarden(ServerLevel world) {
-        return this.warningLevel < 4 ? false : SpawnUtil.trySpawnMob(EntityType.WARDEN, MobSpawnType.TRIGGERED, world, this.getBlockPos(), 20, 5, 6, SpawnUtil.Strategy.ON_TOP_OF_COLLIDER).isPresent();
+        return this.warningLevel < 4 ? false : SpawnUtil.trySpawnMob(EntityType.WARDEN, MobSpawnType.TRIGGERED, world, this.getBlockPos(), 20, 5, 6, SpawnUtil.Strategy.ON_TOP_OF_COLLIDER, org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason.NATURAL, null).isPresent(); // Paper - Entity#getEntitySpawnReason
     }
 
     @Override
diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftEntity.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftEntity.java
index 6fddbcec673564ac531a852f631f6acc460accbd..9ed122efb2b380bb2c1b50fdfe75bf3e679c9c6e 100644
--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftEntity.java
+++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftEntity.java
@@ -991,4 +991,11 @@ public abstract class CraftEntity implements org.bukkit.entity.Entity {
         return this.getHandle().spawnedViaMobSpawner;
     }
     // Paper end - Entity#fromMobSpawner
+
+    // Paper start - entity spawn reason API
+    @Override
+    public org.bukkit.event.entity.CreatureSpawnEvent.SpawnReason getEntitySpawnReason() {
+        return getHandle().spawnReason;
+    }
+    // Paper end - entity spawn reason API
 }