Paper/patches/server/0294-Mob-Spawner-API-Enhancements.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: William Blake Galbreath <blake.galbreath@gmail.com>
Date: Fri, 19 Apr 2019 12:41:13 -0500
Subject: [PATCH] Mob Spawner API Enhancements

== AT ==
public net.minecraft.world.level.BaseSpawner isNearPlayer(Lnet/minecraft/world/level/Level;Lnet/minecraft/core/BlockPos;)Z
public net.minecraft.world.level.BaseSpawner delay(Lnet/minecraft/world/level/Level;Lnet/minecraft/core/BlockPos;)V
public net.minecraft.world.level.BaseSpawner setNextSpawnData(Lnet/minecraft/world/level/Level;Lnet/minecraft/core/BlockPos;Lnet/minecraft/world/level/SpawnData;)V

diff --git a/src/main/java/net/minecraft/world/level/BaseSpawner.java b/src/main/java/net/minecraft/world/level/BaseSpawner.java
index 1d0964a7f544735a0213d5c7832c71f53db139a9..b90127f9f805fdb5bb43a4b8ad2b10499b0b6b78 100644
--- a/src/main/java/net/minecraft/world/level/BaseSpawner.java
+++ b/src/main/java/net/minecraft/world/level/BaseSpawner.java
@@ -237,7 +237,13 @@ public abstract class BaseSpawner {
     }
 
     public void load(@Nullable Level world, BlockPos pos, CompoundTag nbt) {
+        // Paper start - use larger int if set
+        if (nbt.contains("Paper.Delay")) {
+            this.spawnDelay = nbt.getInt("Paper.Delay");
+        } else {
         this.spawnDelay = nbt.getShort("Delay");
+        }
+        // Paper end
         boolean flag = nbt.contains("SpawnData", 10);
 
         if (flag) {
@@ -260,9 +266,15 @@ public abstract class BaseSpawner {
             this.spawnPotentials = SimpleWeightedRandomList.single(this.nextSpawnData != null ? this.nextSpawnData : new SpawnData());
         }
 
+        // Paper start - use ints if set
+        if (nbt.contains("Paper.MinSpawnDelay", net.minecraft.nbt.Tag.TAG_ANY_NUMERIC)) {
+            this.minSpawnDelay = nbt.getInt("Paper.MinSpawnDelay");
+            this.maxSpawnDelay = nbt.getInt("Paper.MaxSpawnDelay");
+            this.spawnCount = nbt.getShort("SpawnCount");
+        } else // Paper end
         if (nbt.contains("MinSpawnDelay", 99)) {
-            this.minSpawnDelay = nbt.getShort("MinSpawnDelay");
-            this.maxSpawnDelay = nbt.getShort("MaxSpawnDelay");
+            this.minSpawnDelay = nbt.getInt("MinSpawnDelay"); // Paper - short -> int
+            this.maxSpawnDelay = nbt.getInt("MaxSpawnDelay"); // Paper - short -> int
             this.spawnCount = nbt.getShort("SpawnCount");
         }
 
@@ -279,9 +291,20 @@ public abstract class BaseSpawner {
     }
 
     public CompoundTag save(CompoundTag nbt) {
-        nbt.putShort("Delay", (short) this.spawnDelay);
-        nbt.putShort("MinSpawnDelay", (short) this.minSpawnDelay);
-        nbt.putShort("MaxSpawnDelay", (short) this.maxSpawnDelay);
+        // Paper start
+        if (spawnDelay > Short.MAX_VALUE) {
+            nbt.putInt("Paper.Delay", this.spawnDelay);
+        }
+        nbt.putShort("Delay", (short) Math.min(Short.MAX_VALUE, this.spawnDelay));
+
+        if (minSpawnDelay > Short.MAX_VALUE || maxSpawnDelay > Short.MAX_VALUE) {
+            nbt.putInt("Paper.MinSpawnDelay", this.minSpawnDelay);
+            nbt.putInt("Paper.MaxSpawnDelay", this.maxSpawnDelay);
+        }
+
+        nbt.putShort("MinSpawnDelay", (short) Math.min(Short.MAX_VALUE, this.minSpawnDelay));
+        nbt.putShort("MaxSpawnDelay", (short) Math.min(Short.MAX_VALUE, this.maxSpawnDelay));
+        // Paper end
         nbt.putShort("SpawnCount", (short) this.spawnCount);
         nbt.putShort("MaxNearbyEntities", (short) this.maxNearbyEntities);
         nbt.putShort("RequiredPlayerRange", (short) this.requiredPlayerRange);
diff --git a/src/main/java/org/bukkit/craftbukkit/block/CraftCreatureSpawner.java b/src/main/java/org/bukkit/craftbukkit/block/CraftCreatureSpawner.java
index 1a8fe7adf7c3ab9eb4cbc9847df4cfc872b97921..ebd6b07b8bcad3bc621fe99b0bee394fd2dd154f 100644
--- a/src/main/java/org/bukkit/craftbukkit/block/CraftCreatureSpawner.java
+++ b/src/main/java/org/bukkit/craftbukkit/block/CraftCreatureSpawner.java
@@ -256,4 +256,36 @@ public class CraftCreatureSpawner extends CraftBlockEntityState<SpawnerBlockEnti
                 new HashMap<>(nms.slotDropChances().entrySet().stream().collect(Collectors.toMap((entry) -> CraftEquipmentSlot.getSlot(entry.getKey()), Map.Entry::getValue)))
         )).orElse(null);
     }
+
+    // Paper start
+    @Override
+    public boolean isActivated() {
+        this.requirePlaced();
+        return this.getSnapshot().getSpawner().isNearPlayer(this.world.getHandle(), this.getPosition());
+    }
+
+    @Override
+    public void resetTimer() {
+        this.requirePlaced();
+        this.getSnapshot().getSpawner().delay(this.world.getHandle(), this.getPosition());
+    }
+
+    @Override
+    public void setSpawnedItem(org.bukkit.inventory.ItemStack itemStack) {
+        Preconditions.checkArgument(itemStack != null && !itemStack.getType().isAir(), "spawners cannot spawn air");
+        net.minecraft.world.item.ItemStack item = org.bukkit.craftbukkit.inventory.CraftItemStack.asNMSCopy(itemStack);
+        net.minecraft.nbt.CompoundTag entity = new net.minecraft.nbt.CompoundTag();
+        entity.putString("id", net.minecraft.core.registries.BuiltInRegistries.ENTITY_TYPE.getKey(net.minecraft.world.entity.EntityType.ITEM).toString());
+        entity.put("Item", item.save(this.world.getHandle().registryAccess()));
+        this.getSnapshot().getSpawner().setNextSpawnData(
+            this.isPlaced() ? this.world.getHandle() : null,
+            this.getPosition(),
+            new net.minecraft.world.level.SpawnData(
+                entity,
+                java.util.Optional.empty(),
+                Optional.ofNullable(this.getSnapshot().getSpawner().nextSpawnData).flatMap(SpawnData::equipment)
+            )
+        );
+    }
+    // Paper end
 }