From 95b1d64ff38307c80fb25b6f813466ffde17bd68 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Sun, 9 Sep 2018 13:30:00 -0400
Subject: [PATCH] Mob Pathfinding API

Implements Pathfinding API for mobs

diff --git a/src/main/java/com/destroystokyo/paper/entity/PaperPathfinder.java b/src/main/java/com/destroystokyo/paper/entity/PaperPathfinder.java
new file mode 100644
index 0000000000..f68a07cb96
--- /dev/null
+++ b/src/main/java/com/destroystokyo/paper/entity/PaperPathfinder.java
@@ -0,0 +1,111 @@
+package com.destroystokyo.paper.entity;
+
+import net.minecraft.server.EntityInsentient;
+import net.minecraft.server.PathEntity;
+import net.minecraft.server.PathPoint;
+import org.apache.commons.lang.Validate;
+import org.bukkit.Location;
+import org.bukkit.craftbukkit.entity.CraftLivingEntity;
+import org.bukkit.entity.LivingEntity;
+import org.bukkit.entity.Mob;
+
+import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
+import java.util.ArrayList;
+import java.util.List;
+
+public class PaperPathfinder implements com.destroystokyo.paper.entity.Pathfinder {
+
+    private final EntityInsentient entity;
+
+    public PaperPathfinder(EntityInsentient entity) {
+        this.entity = entity;
+    }
+
+    @Override
+    public Mob getEntity() {
+        return entity.getBukkitMob();
+    }
+
+    @Override
+    public void stopPathfinding() {
+        entity.getNavigation().stopPathfinding();
+    }
+
+    @Override
+    public boolean hasPath() {
+        return entity.getNavigation().getPathEntity() != null;
+    }
+
+    @Nullable
+    @Override
+    public PathResult getCurrentPath() {
+        PathEntity path = entity.getNavigation().getPathEntity();
+        return path != null ? new PaperPathResult(path) : null;
+    }
+
+    @Nullable
+    @Override
+    public PathResult findPath(Location loc) {
+        Validate.notNull(loc, "Location can not be null");
+        PathEntity path = entity.getNavigation().calculateDestination(loc.getX(), loc.getY(), loc.getZ());
+        return path != null ? new PaperPathResult(path) : null;
+    }
+
+    @Nullable
+    @Override
+    public PathResult findPath(LivingEntity target) {
+        Validate.notNull(target, "Target can not be null");
+        PathEntity path = entity.getNavigation().calculateDestination(((CraftLivingEntity) target).getHandle());
+        return path != null ? new PaperPathResult(path) : null;
+    }
+
+    @Override
+    public boolean moveTo(@Nonnull PathResult path, double speed) {
+        Validate.notNull(path, "PathResult can not be null");
+        PathEntity pathEntity = ((PaperPathResult) path).path;
+        return entity.getNavigation().setDestination(pathEntity, speed);
+    }
+
+    public class PaperPathResult implements com.destroystokyo.paper.entity.PaperPathfinder.PathResult {
+
+        private final PathEntity path;
+        PaperPathResult(PathEntity path) {
+            this.path = path;
+        }
+
+        @Nullable
+        @Override
+        public Location getFinalPoint() {
+            PathPoint point = path.getFinalPoint();
+            return point != null ? toLoc(point) : null;
+        }
+
+        @Override
+        public List<Location> getPoints() {
+            List<Location> points = new ArrayList<>();
+            for (PathPoint point : path.getPoints()) {
+                points.add(toLoc(point));
+            }
+            return points;
+        }
+
+        @Override
+        public int getNextPointIndex() {
+            return path.getNextIndex();
+        }
+
+        @Nullable
+        @Override
+        public Location getNextPoint() {
+            if (!path.hasNext()) {
+                return null;
+            }
+            return toLoc(path.getPoints().get(path.getNextIndex()));
+        }
+    }
+
+    private Location toLoc(PathPoint point) {
+        return new Location(entity.world.getWorld(), point.getX(), point.getY(), point.getZ());
+    }
+}
diff --git a/src/main/java/net/minecraft/server/NavigationAbstract.java b/src/main/java/net/minecraft/server/NavigationAbstract.java
index bdd092e49d..f06764973f 100644
--- a/src/main/java/net/minecraft/server/NavigationAbstract.java
+++ b/src/main/java/net/minecraft/server/NavigationAbstract.java
@@ -80,7 +80,7 @@ public abstract class NavigationAbstract {
     }
 
     @Nullable
-    public final PathEntity a(double d0, double d1, double d2, int i) {
+    public final PathEntity calculateDestination(double d0, double d1, double d2) { return a(d0, d1, d2, 0); } public final PathEntity a(double d0, double d1, double d2, int i) { // Paper - OBFHELPER
         return this.a(new BlockPosition(d0, d1, d2), i);
     }
 
@@ -100,7 +100,7 @@ public abstract class NavigationAbstract {
     }
 
     @Nullable
-    public PathEntity a(Entity entity, int i) {
+    public final PathEntity calculateDestination(Entity entity) { return a(entity, 0); }  public PathEntity a(Entity entity, int i) {
         return this.a(ImmutableSet.of(new BlockPosition(entity)), entity, 16, true, i); // Paper
     }
 
@@ -164,6 +164,7 @@ public abstract class NavigationAbstract {
         return pathentity != null && this.a(pathentity, d0);
     }
 
+    public boolean setDestination(@Nullable PathEntity pathentity, double speed) { return a(pathentity, speed); } // Paper - OBFHELPER
     public boolean a(@Nullable PathEntity pathentity, double d0) {
         if (pathentity == null) {
             this.c = null;
@@ -191,7 +192,7 @@ public abstract class NavigationAbstract {
         }
     }
 
-    @Nullable
+    @Nullable public PathEntity getPathEntity() { return k(); } @Nullable // Paper - OBFHELPER
     public PathEntity k() {
         return this.c;
     }
@@ -281,6 +282,7 @@ public abstract class NavigationAbstract {
         return !this.m();
     }
 
+    public void stopPathfinding() { o(); } // Paper - OBFHELPER
     public void o() {
         this.c = null;
     }
diff --git a/src/main/java/net/minecraft/server/PathEntity.java b/src/main/java/net/minecraft/server/PathEntity.java
index 312352ef84..dcb4e25080 100644
--- a/src/main/java/net/minecraft/server/PathEntity.java
+++ b/src/main/java/net/minecraft/server/PathEntity.java
@@ -5,13 +5,14 @@ import javax.annotation.Nullable;
 
 public class PathEntity {
 
-    private final List<PathPoint> a;
+    private final List<PathPoint> a; public List<PathPoint> getPoints() { return a; } // Paper - OBFHELPER
     private PathPoint[] b = new PathPoint[0];
     private PathPoint[] c = new PathPoint[0];
-    private int e;
+    private int e; public int getNextIndex() { return this.e; } // Paper - OBFHELPER
     private final BlockPosition f;
     private final float g;
     private final boolean h;
+    public boolean hasNext() { return getNextIndex() < getPoints().size(); } // Paper
 
     public PathEntity(List<PathPoint> list, BlockPosition blockposition, boolean flag) {
         this.a = list;
@@ -28,8 +29,7 @@ public class PathEntity {
         return this.e >= this.a.size();
     }
 
-    @Nullable
-    public PathPoint c() {
+    public PathPoint getFinalPoint() { return c(); } @Nullable public PathPoint c() { // Paper - OBFHELPER
         return !this.a.isEmpty() ? (PathPoint) this.a.get(this.a.size() - 1) : null;
     }
 
@@ -77,7 +77,7 @@ public class PathEntity {
         return this.a(entity, this.e);
     }
 
-    public Vec3D g() {
+    public Vec3D getNext() { return g(); } public Vec3D g() { // Paper - OBFHELPER
         PathPoint pathpoint = (PathPoint) this.a.get(this.e);
 
         return new Vec3D((double) pathpoint.a, (double) pathpoint.b, (double) pathpoint.c);
diff --git a/src/main/java/net/minecraft/server/PathPoint.java b/src/main/java/net/minecraft/server/PathPoint.java
index b1db95daa9..18cdd2a6f2 100644
--- a/src/main/java/net/minecraft/server/PathPoint.java
+++ b/src/main/java/net/minecraft/server/PathPoint.java
@@ -2,9 +2,9 @@ package net.minecraft.server;
 
 public class PathPoint {
 
-    public final int a;
-    public final int b;
-    public final int c;
+    public final int a; public final int getX() { return a; } // Paper - OBFHELPER
+    public final int b; public final int getY() { return b; } // Paper - OBFHELPER
+    public final int c; public final int getZ() { return c; } // Paper - OBFHELPER
     private final int m;
     public int d = -1;
     public float e;
diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftMob.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftMob.java
index 90e63fbf29..c89bc7024b 100644
--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftMob.java
+++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftMob.java
@@ -12,8 +12,11 @@ import org.bukkit.loot.LootTable;
 public abstract class CraftMob extends CraftLivingEntity implements Mob {
     public CraftMob(CraftServer server, EntityInsentient entity) {
         super(server, entity);
+         paperPathfinder = new com.destroystokyo.paper.entity.PaperPathfinder(entity); // Paper
     }
 
+    private final com.destroystokyo.paper.entity.PaperPathfinder paperPathfinder; // Paper
+    @Override public com.destroystokyo.paper.entity.Pathfinder getPathfinder() { return paperPathfinder; } // Paper
     @Override
     public void setTarget(LivingEntity target) {
         EntityInsentient entity = getHandle();
-- 
2.25.1