3 files changed, 51 insertions, 2 deletions

diff --git a/src/Blocks/BlockHandler.cpp b/src/Blocks/BlockHandler.cpp
index 60f13a747..7f1d72159 100644
--- a/src/Blocks/BlockHandler.cpp
+++ b/src/Blocks/BlockHandler.cpp
@@ -500,6 +500,43 @@ void cBlockHandler::DropBlock(cChunkInterface & a_ChunkInterface, cWorldInterfac
 
 
 
+bool cBlockHandler::CanBeAt(cWorld * a_World, int a_BlockX, int a_BlockY, int a_BlockZ)
+{
+	class cCallback : public cChunkCallback
+	{
+	public:
+		cCallback(cChunkInterface & a_ChunkInterface, int a_RelX, int a_RelY, int a_RelZ, cBlockHandler * a_BlockHandler) :
+			m_ChunkInterface(a_ChunkInterface),
+			m_RelX(a_RelX),
+			m_RelY(a_RelY),
+			m_RelZ(a_RelZ),
+			m_Handler(a_BlockHandler)
+		{
+		}
+
+		virtual bool Item(cChunk * a_Chunk)
+		{
+			return m_Handler->CanBeAt(m_ChunkInterface, m_RelX, m_RelY, m_RelZ, *a_Chunk);
+		}
+
+	protected:
+		cChunkInterface & m_ChunkInterface;
+		int m_RelX, m_RelY, m_RelZ;
+		cBlockHandler * m_Handler;
+	};
+
+	int ChunkX, ChunkZ;
+	cChunkDef::AbsoluteToRelative(a_BlockX, a_BlockY, a_BlockZ, ChunkX, ChunkZ);
+	cChunkInterface ChunkInterface(a_World->GetChunkMap());
+
+	cCallback Callback(ChunkInterface, a_BlockX, a_BlockY, a_BlockZ, this);
+	return a_World->GetChunkMap()->DoWithChunk(ChunkX, ChunkZ, Callback);
+}
+
+
+
+
+
 bool cBlockHandler::CanBeAt(cChunkInterface & a_ChunkInterface, int a_BlockX, int a_BlockY, int a_BlockZ, const cChunk & a_Chunk)
 {
 	return true;
diff --git a/src/Blocks/BlockHandler.h b/src/Blocks/BlockHandler.h
index f2298afb5..6c782da8c 100644
--- a/src/Blocks/BlockHandler.h
+++ b/src/Blocks/BlockHandler.h
@@ -14,6 +14,7 @@ class cBlockPluginInterface;
 class cChunkInterface;
 class cWorldInterface;
 class cItems;
+class cWorld;
 
 
 
@@ -83,7 +84,10 @@ public:
 	@param a_DropVerbatim Calls ConvertToVerbatimPickups() instead of its counterpart, meaning the block itself is dropped by default (due to a speical tool or enchantment)
 	*/
 	virtual void DropBlock(cChunkInterface & a_ChunkInterface, cWorldInterface & a_WorldInterface, cBlockPluginInterface & a_BlockPluginInterface, cEntity * a_Digger, int a_BlockX, int a_BlockY, int a_BlockZ, bool a_CanDrop = true);
-	
+
+	/** Checks if the block can stay at the specified absolute coords */
+	bool CanBeAt(cWorld * a_World, int a_BlockX, int a_BlockY, int a_BlockZ);
+
 	/// Checks if the block can stay at the specified relative coords in the chunk
 	virtual bool CanBeAt(cChunkInterface & a_ChunkInterface, int a_RelX, int a_RelY, int a_RelZ, const cChunk & a_Chunk);
 
diff --git a/src/ClientHandle.cpp b/src/ClientHandle.cpp
index a6cbad32a..aefff9aa7 100644
--- a/src/ClientHandle.cpp
+++ b/src/ClientHandle.cpp
@@ -1493,6 +1493,15 @@ void cClientHandle::HandlePlaceBlock(int a_BlockX, int a_BlockY, int a_BlockZ, e
 	}
 	
 	cBlockHandler * NewBlock = BlockHandler(BlockType);
+	cChunkInterface ChunkInterface(World->GetChunkMap());
+
+	if (!NewBlock->CanBeAt(World, a_BlockX, a_BlockY, a_BlockZ))
+	{
+		// Handler refused the placement, send that information back to the client:
+		World->SendBlockTo(a_BlockX, a_BlockY, a_BlockZ, m_Player);
+		m_Player->GetInventory().SendEquippedSlot();
+		return;
+	}
 
 	if (cRoot::Get()->GetPluginManager()->CallHookPlayerPlacingBlock(*m_Player, a_BlockX, a_BlockY, a_BlockZ, a_BlockFace, a_CursorX, a_CursorY, a_CursorZ, BlockType, BlockMeta))
 	{
@@ -1509,7 +1518,6 @@ void cClientHandle::HandlePlaceBlock(int a_BlockX, int a_BlockY, int a_BlockZ, e
 		m_Player->GetInventory().RemoveOneEquippedItem();
 	}
 
-	cChunkInterface ChunkInterface(World->GetChunkMap());
 	NewBlock->OnPlacedByPlayer(ChunkInterface, *World, m_Player, a_BlockX, a_BlockY, a_BlockZ, a_BlockFace, a_CursorX, a_CursorY, a_CursorZ, BlockType, BlockMeta);
 	
 	AString PlaceSound = cBlockInfo::GetPlaceSound(BlockType);