Implement data storage for Entitiies (#748)

src/common/Utilities/DataMap.h

@@ -0,0 +1,34 @@
+/*
+ * Originally written by Rochet2 - Copyright (C) 2018+ AzerothCore <www.azerothcore.org>, released under GNU AGPL v3 license: http://github.com/azerothcore/azerothcore-wotlk/LICENSE-AGPL
+ */
+
+#ifndef _DATA_MAP_H_
+#define _DATA_MAP_H_
+
+#include <string>
+#include <unordered_map>
+#include <memory>
+
+class DataMap
+{
+public:
+    class Base
+    {
+    public:
+        virtual ~Base() = default;
+    };
+
+    template<class T> T* GetCustomData(std::string const & k) const {
+        static_assert(std::is_base_of<Base, T>::value, "T must derive from Base");
+        auto it = Container.find(k);
+        if (it != Container.end())
+            return dynamic_cast<T*>(it->second.get());
+        return nullptr;
+    }
+    void SetCustomData(std::string const & k, Base* v) { Container[k] = std::unique_ptr<Base>(v); }
+
+private:
+    std::unordered_map<std::string, std::unique_ptr<Base>> Container;
+};
+
+#endif

src/server/game/Entities/Object/Object.h

@@ -8,6 +8,7 @@
 #define _OBJECT_H
 
 #include "Common.h"
+#include "DataMap.h"
 #include "UpdateMask.h"
 #include "UpdateData.h"
 #include "GridReference.h"
@@ -318,6 +319,8 @@ class Object
         DynamicObject* ToDynObject() { if (GetTypeId() == TYPEID_DYNAMICOBJECT) return reinterpret_cast<DynamicObject*>(this); else return NULL; }
         DynamicObject const* ToDynObject() const { if (GetTypeId() == TYPEID_DYNAMICOBJECT) return reinterpret_cast<DynamicObject const*>(this); else return NULL; }
 
+        DataMap DataMap;
+
     protected:
 
         Object();