Fix various issues

src/main/java/xonin/backhand/client/utils/BackhandClientUtils.java

@@ -51,7 +51,7 @@ public static boolean canBlockBeInteractedWith(ItemStack offhand, int x, int y,
         float subY = (float) mop.hitVec.yCoord - y;
         float subZ = (float) mop.hitVec.zCoord - z;
 
-        Block block = DummyWorld.INSTANCE.copyAndSetBlock(mc.theWorld, x, y, z);
+        Block block = DummyWorld.INSTANCE.copyAndSetBlock(mc.theWorld, x, y, z, mop);
         if (block == null) return false;
         ClientFakePlayer.INSTANCE.prepareForInteraction(mc.thePlayer, stack);
 

src/main/java/xonin/backhand/client/world/DummyWorld.java

@@ -1,13 +1,17 @@
 package xonin.backhand.client.world;
 
 import javax.annotation.Nonnull;
+import javax.annotation.Nullable;
 
 import net.minecraft.block.Block;
 import net.minecraft.entity.Entity;
 import net.minecraft.init.Blocks;
+import net.minecraft.item.ItemStack;
 import net.minecraft.nbt.NBTTagCompound;
 import net.minecraft.profiler.Profiler;
 import net.minecraft.tileentity.TileEntity;
+import net.minecraft.util.MovingObjectPosition;
+import net.minecraft.util.Vec3;
 import net.minecraft.world.EnumSkyBlock;
 import net.minecraft.world.World;
 import net.minecraft.world.WorldProviderSurface;
@@ -26,6 +30,9 @@ public class DummyWorld extends World {
 
     public static final DummyWorld INSTANCE = new DummyWorld();
 
+    public Block boundBlock;
+    public Vec3 boundBlockPos;
+
     public DummyWorld() {
         super(new DummySaveHandler(), "DummyServer", DEFAULT_SETTINGS, new WorldProviderSurface(), new Profiler());
         // Guarantee the dimension ID was not reset by the provider
@@ -70,23 +77,58 @@ public boolean updateLightByType(EnumSkyBlock p_147463_1_, int p_147463_2_, int
         return true;
     }
 
-    public Block copyAndSetBlock(World world, int x, int y, int z) {
+    @Override
+    public TileEntity getTileEntity(int x, int y, int z) {
+        if (boundBlock == null) return super.getTileEntity(x, y, z);
+        return super.getTileEntity((int) boundBlockPos.xCoord, (int) boundBlockPos.yCoord, (int) boundBlockPos.zCoord);
+    }
+
+    @Override
+    public Block getBlock(int x, int y, int z) {
+        if (boundBlock == null) return super.getBlock(x, y, z);
+        return boundBlock;
+    }
+
+    @Nullable
+    public Block copyAndSetBlock(World world, int x, int y, int z, MovingObjectPosition mop) {
+        reset();
         setBlockToAir(x, y, z);
         Block block = world.getBlock(x, y, z);
 
         if (block == null || block == Blocks.air) return null;
 
         int meta = block.getDamageValue(world, x, y, z);
-        DummyWorld.INSTANCE.setBlock(x, y, z, block, meta, 3);
+        ItemStack stack = block.getPickBlock(mop, world, x, y, z, ClientFakePlayer.INSTANCE);
+
+        if (stack == null || !stack.getItem()
+            .onItemUse(stack, ClientFakePlayer.INSTANCE, this, x, y, z, mop.sideHit, x, y, z)) {
+            setBlock(x, y, z, block, meta, 3);
+            setBoundBlock(block, x, y, z);
+        }
+
         TileEntity tile = world.getTileEntity(x, y, z);
         if (tile != null) {
             NBTTagCompound tag = new NBTTagCompound();
             tile.writeToNBT(tag);
-            TileEntity dummyTile = TileEntity.createAndLoadEntity(tag);
-            DummyWorld.INSTANCE.setTileEntity(x, y, z, dummyTile);
+            TileEntity dummyTile = getTileEntity(x, y, z);
+            if (dummyTile == null) {
+                dummyTile = TileEntity.createAndLoadEntity(tag);
+                setTileEntity(x, y, z, dummyTile);
+            }
+            dummyTile.readFromNBT(tag);
         }
 
         return getBlock(x, y, z);
     }
 
+    public void setBoundBlock(Block block, int x, int y, int z) {
+        boundBlock = block;
+        boundBlockPos = Vec3.createVectorHelper(x, y, z);
+    }
+
+    public void reset() {
+        boundBlock = null;
+        boundBlockPos = null;
+    }
+
 }