1 files changed, 62 insertions, 0 deletions
diff --git a/src/core/Containers.h b/src/core/Containers.h
new file mode 100644
index 0000000000..d5974cefab
--- /dev/null
+++ b/src/core/Containers.h
@@ -0,0 +1,62 @@
+/*
+ * Copyright (C) 
+ *
+ * Copyright (C) 2008-2016 TrinityCore <http://www.trinitycore.org/>
+ * Copyright (C) 2005-2009 MaNGOS <http://getmangos.com/>
+ */
+
+#ifndef TRINITY_CONTAINERS_H
+#define TRINITY_CONTAINERS_H
+
+#include "Define.h"
+#include <list>
+
+//! Because circular includes are bad
+extern uint32 urand(uint32 min, uint32 max);
+
+namespace Trinity
+{
+    namespace Containers
+    {
+        template<class T>
+        void RandomResizeList(std::list<T> &list, uint32 size)
+        {
+            size_t list_size = list.size();
+
+            while (list_size > size)
+            {
+                typename std::list<T>::iterator itr = list.begin();
+                std::advance(itr, urand(0, list_size - 1));
+                list.erase(itr);
+                --list_size;
+            }
+        }
+
+        template<class T, class Predicate>
+        void RandomResizeList(std::list<T> &list, Predicate& predicate, uint32 size)
+        {
+            //! First use predicate filter
+            std::list<T> listCopy;
+            for (typename std::list<T>::iterator itr = list.begin(); itr != list.end(); ++itr)
+                if (predicate(*itr))
+                    listCopy.push_back(*itr);
+
+            if (size)
+                RandomResizeList(listCopy, size);
+
+            list = listCopy;
+        }
+
+        /* Select a random element from a container. Note: make sure you explicitly empty check the container */
+        template <class C> typename C::value_type const& SelectRandomContainerElement(C const& container)
+        {
+            typename C::const_iterator it = container.begin();
+            std::advance(it, urand(0, container.size() - 1));
+            return *it;
+        }
+    }
+    //! namespace Containers
+}
+//! namespace Trinity
+
+#endif //! #ifdef TRINITY_CONTAINERS_H