From d084c3abef084cb894059e7755a1062d4aca0b24 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Mon, 10 Sep 2018 23:56:36 -0400
Subject: [PATCH] Prevent Mob AI Rules from Loading Chunks


diff --git a/src/main/java/net/minecraft/server/Chunk.java b/src/main/java/net/minecraft/server/Chunk.java
index 1d301dcb70..33f5aa721f 100644
--- a/src/main/java/net/minecraft/server/Chunk.java
+++ b/src/main/java/net/minecraft/server/Chunk.java
@@ -488,6 +488,7 @@ public class Chunk implements IChunkAccess {
         }
     }
 
+    public Fluid getFluid(BlockPosition blockposition) { return b(blockposition); } // Paper - OBFHELPER
     public Fluid b(BlockPosition blockposition) {
         return this.b(blockposition.getX(), blockposition.getY(), blockposition.getZ());
     }
diff --git a/src/main/java/net/minecraft/server/PathfinderGoalRemoveBlock.java b/src/main/java/net/minecraft/server/PathfinderGoalRemoveBlock.java
index b1661693cf..2cbb6c8f91 100644
--- a/src/main/java/net/minecraft/server/PathfinderGoalRemoveBlock.java
+++ b/src/main/java/net/minecraft/server/PathfinderGoalRemoveBlock.java
@@ -7,11 +7,13 @@ public class PathfinderGoalRemoveBlock extends PathfinderGoalGotoTarget {
     private final Block f;
     private final EntityInsentient g;
     private int h;
+    private World world; // Paper
 
     public PathfinderGoalRemoveBlock(Block block, EntityCreature entitycreature, double d0, int i) {
         super(entitycreature, d0, 24, i);
         this.f = block;
         this.g = entitycreature;
+        this.world = entitycreature.world; // Paper
     }
 
     public boolean a() {
@@ -89,13 +91,15 @@ public class PathfinderGoalRemoveBlock extends PathfinderGoalGotoTarget {
 
     @Nullable
     private BlockPosition a(BlockPosition blockposition, IBlockAccess iblockaccess) {
-        if (iblockaccess.getType(blockposition).getBlock() == this.f) {
+        Block block = world.getBlockIfLoaded(blockposition); // Paper
+        if (block == null) return null; // Paper
+        if (block == this.f) { // Paper
             return blockposition;
         } else {
             BlockPosition[] ablockposition = new BlockPosition[]{blockposition.down(), blockposition.west(), blockposition.east(), blockposition.north(), blockposition.south(), blockposition.down().down()};
 
             for(BlockPosition blockposition1 : ablockposition) {
-                if (iblockaccess.getType(blockposition1).getBlock() == this.f) {
+                if (world.getBlockIfLoaded(blockposition1) == this.f) { // Paper
                     return blockposition1;
                 }
             }
@@ -105,7 +109,8 @@ public class PathfinderGoalRemoveBlock extends PathfinderGoalGotoTarget {
     }
 
     protected boolean a(IWorldReader iworldreader, BlockPosition blockposition) {
-        Block block = iworldreader.getType(blockposition).getBlock();
+        Block block = world.getBlockIfLoaded(blockposition); // Paper
+        if (block == null) return false; // Paper
         return block == this.f && iworldreader.getType(blockposition.up()).isAir() && iworldreader.getType(blockposition.up(2)).isAir();
     }
 }
diff --git a/src/main/java/net/minecraft/server/RandomPositionGenerator.java b/src/main/java/net/minecraft/server/RandomPositionGenerator.java
index 800e0046a8..bfa6c2eef8 100644
--- a/src/main/java/net/minecraft/server/RandomPositionGenerator.java
+++ b/src/main/java/net/minecraft/server/RandomPositionGenerator.java
@@ -78,6 +78,7 @@ public class RandomPositionGenerator {
                 }
 
                 BlockPosition blockposition2 = new BlockPosition((double)j1 + entitycreature.locX, (double)k1 + entitycreature.locY, (double)l1 + entitycreature.locZ);
+                if (!entitycreature.world.isLoaded(blockposition2)) continue; // Paper
                 if ((!flag1 || entitycreature.f(blockposition2)) && navigationabstract.a(blockposition2)) {
                     if (!flag) {
                         blockposition2 = a(blockposition2, entitycreature);
@@ -141,6 +142,7 @@ public class RandomPositionGenerator {
     }
 
     private static boolean b(BlockPosition blockposition, EntityCreature entitycreature) {
-        return entitycreature.world.b(blockposition).a(TagsFluid.WATER);
+        Fluid fluid = entitycreature.world.getFluidIfLoaded(blockposition); // Paper
+        return fluid != null && fluid.a(TagsFluid.WATER); // Paper
     }
 }
diff --git a/src/main/java/net/minecraft/server/World.java b/src/main/java/net/minecraft/server/World.java
index acd0c93cec..dbdda0a127 100644
--- a/src/main/java/net/minecraft/server/World.java
+++ b/src/main/java/net/minecraft/server/World.java
@@ -756,6 +756,18 @@ public abstract class World implements IEntityAccess, GeneratorAccess, IIBlockAc
         }
     }
 
+    // Paper start
+    public Fluid getFluidIfLoaded(BlockPosition blockposition) {
+        if (blockposition.isInvalidYLocation()) { // Paper
+            return getFluid(blockposition);
+        } else {
+            Chunk chunk = this.getChunkIfLoaded(blockposition);
+
+            return chunk != null ? chunk.getFluid(blockposition) : null;
+        }
+    }
+    // Paper end
+    public Fluid getFluid(BlockPosition blockposition) { return b(blockposition); } // Paper - OBFHELPER
     public Fluid b(BlockPosition blockposition) {
         if (blockposition.isInvalidYLocation()) { // Paper
             return FluidTypes.a.i();
-- 
2.18.0