From 4a7683d5bf59da1532ab38dcbe69322b8ff4f174 Mon Sep 17 00:00:00 2001
From: FrozenBrain <me@frozenbrain.eu>
Date: Thu, 19 May 2016 19:16:59 +0200
Subject: [PATCH] Apply transformations to NBT data of tile entities (fixes
 rotation of skulls)

---
 .../function/block/ExtentBlockCopy.java       | 46 ++++++++++-
 .../internal/helper/MCDirections.java         | 78 +++++++++++++++++++
 2 files changed, 123 insertions(+), 1 deletion(-)

diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/function/block/ExtentBlockCopy.java b/worldedit-core/src/main/java/com/sk89q/worldedit/function/block/ExtentBlockCopy.java
index f7bdf8e11..94e39cd0c 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/function/block/ExtentBlockCopy.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/function/block/ExtentBlockCopy.java
@@ -19,12 +19,17 @@
 
 package com.sk89q.worldedit.function.block;
 
-import com.sk89q.worldedit.extent.Extent;
+import com.sk89q.jnbt.CompoundTag;
+import com.sk89q.jnbt.CompoundTagBuilder;
 import com.sk89q.worldedit.Vector;
 import com.sk89q.worldedit.WorldEditException;
 import com.sk89q.worldedit.blocks.BaseBlock;
+import com.sk89q.worldedit.extent.Extent;
 import com.sk89q.worldedit.function.RegionFunction;
+import com.sk89q.worldedit.internal.helper.MCDirections;
 import com.sk89q.worldedit.math.transform.Transform;
+import com.sk89q.worldedit.util.Direction;
+import com.sk89q.worldedit.util.Direction.Flag;
 
 import static com.google.common.base.Preconditions.checkNotNull;
 
@@ -66,7 +71,46 @@ public class ExtentBlockCopy implements RegionFunction {
         BaseBlock block = source.getBlock(position);
         Vector orig = position.subtract(from);
         Vector transformed = transform.apply(orig);
+
+        // Apply transformations to NBT data if necessary
+        block = transformNbtData(block);
+
         return destination.setBlock(transformed.add(to), block);
     }
 
+    /**
+     * Transform NBT data in the given block state and return a new instance
+     * if the NBT data needs to be transformed.
+     *
+     * @param state the existing state
+     * @return a new state or the existing one
+     */
+    private BaseBlock transformNbtData(BaseBlock state) {
+        CompoundTag tag = state.getNbtData();
+
+        if (tag != null) {
+            // Handle blocks which store their rotation in NBT
+            if (tag.containsKey("Rot")) {
+                int rot = tag.asInt("Rot");
+
+                Direction direction = MCDirections.fromRotation(rot);
+
+                if (direction != null) {
+                    Vector vector = transform.apply(direction.toVector()).subtract(transform.apply(Vector.ZERO)).normalize();
+                    Direction newDirection = Direction.findClosest(vector, Flag.CARDINAL | Flag.ORDINAL | Flag.SECONDARY_ORDINAL);
+
+                    if (newDirection != null) {
+                        CompoundTagBuilder builder = tag.createBuilder();
+
+                        builder.putByte("Rot", (byte) MCDirections.toRotation(newDirection));
+
+                        return new BaseBlock(state.getId(), state.getData(), builder.build());
+                    }
+                }
+            }
+        }
+
+        return state;
+    }
+
 }
diff --git a/worldedit-core/src/main/java/com/sk89q/worldedit/internal/helper/MCDirections.java b/worldedit-core/src/main/java/com/sk89q/worldedit/internal/helper/MCDirections.java
index d9e75d62f..16e25e354 100644
--- a/worldedit-core/src/main/java/com/sk89q/worldedit/internal/helper/MCDirections.java
+++ b/worldedit-core/src/main/java/com/sk89q/worldedit/internal/helper/MCDirections.java
@@ -77,4 +77,82 @@ public final class MCDirections {
         }
     }
 
+    public static Direction fromRotation(int i) {
+        switch (i) {
+            case 0:
+                return Direction.SOUTH;
+            case 1:
+                return Direction.SOUTH_SOUTHWEST;
+            case 2:
+                return Direction.SOUTHWEST;
+            case 3:
+                return Direction.WEST_SOUTHWEST;
+            case 4:
+                return Direction.WEST;
+            case 5:
+                return Direction.WEST_NORTHWEST;
+            case 6:
+                return Direction.NORTHWEST;
+            case 7:
+                return Direction.NORTH_NORTHWEST;
+            case 8:
+                return Direction.NORTH;
+            case 9:
+                return Direction.NORTH_NORTHEAST;
+            case 10:
+                return Direction.NORTHEAST;
+            case 11:
+                return Direction.EAST_NORTHEAST;
+            case 12:
+                return Direction.EAST;
+            case 13:
+                return Direction.EAST_SOUTHEAST;
+            case 14:
+                return Direction.SOUTHEAST;
+            case 15:
+                return Direction.SOUTH_SOUTHEAST;
+            default:
+                return Direction.NORTH;
+        }
+    }
+
+    public static int toRotation(Direction direction) {
+        switch (direction) {
+            case SOUTH:
+                return 0;
+            case SOUTH_SOUTHWEST:
+                return 1;
+            case SOUTHWEST:
+                return 2;
+            case WEST_SOUTHWEST:
+                return 3;
+            case WEST:
+                return 4;
+            case WEST_NORTHWEST:
+                return 5;
+            case NORTHWEST:
+                return 6;
+            case NORTH_NORTHWEST:
+                return 7;
+            case NORTH:
+                return 8;
+            case NORTH_NORTHEAST:
+                return 9;
+            case NORTHEAST:
+                return 10;
+            case EAST_NORTHEAST:
+                return 11;
+            case EAST:
+                return 12;
+            case EAST_SOUTHEAST:
+                return 13;
+            case SOUTHEAST:
+                return 14;
+            case SOUTH_SOUTHEAST:
+                return 15;
+            default:
+                return 0;
+        }
+    }
+
 }