/*
 * Copyright (C) 2016+     AzerothCore <www.azerothcore.org>, released under GNU GPL v2 license, you may redistribute it and/or modify it under version 2 of the License, or (at your option), any later version.
 * Copyright (C) 2008-2016 TrinityCore <http://www.trinitycore.org/>
 * Copyright (C) 2005-2009 MaNGOS <http://getmangos.com/>
 */

#ifndef ACORE_OBJECTREGISTRY_H
#define ACORE_OBJECTREGISTRY_H

#include "Define.h"
#include <string>
#include <vector>
#include <map>
#include <unordered_map>

/** ObjectRegistry holds all registry item of the same type
 */
template<class T, class Key = std::string>
class ObjectRegistry
{
public:
    typedef std::map<Key, T*> RegistryMapType;

    /// Returns a registry item
    const T* GetRegistryItem(Key key) const
    {
        typename RegistryMapType::const_iterator iter = i_registeredObjects.find(key);
        return ( iter == i_registeredObjects.end() ? nullptr : iter->second );
    }

    static ObjectRegistry<T, Key>* instance()
    {
        static ObjectRegistry<T, Key>* instance = new ObjectRegistry<T, Key>();
        return instance;
    }

    /// Inserts a registry item
    bool InsertItem(T* obj, Key key, bool override = false)
    {
        typename RegistryMapType::iterator iter = i_registeredObjects.find(key);
        if ( iter != i_registeredObjects.end() )
        {
            if ( !override )
                return false;
            delete iter->second;
            i_registeredObjects.erase(iter);
        }

        i_registeredObjects[key] = obj;
        return true;
    }

    /// Removes a registry item
    void RemoveItem(Key key, bool delete_object = true)
    {
        typename RegistryMapType::iterator iter = i_registeredObjects.find(key);
        if ( iter != i_registeredObjects.end() )
        {
            if ( delete_object )
                delete iter->second;
            i_registeredObjects.erase(iter);
        }
    }

    /// Returns true if registry contains an item
    bool HasItem(Key key) const
    {
        return (i_registeredObjects.find(key) != i_registeredObjects.end());
    }

    /// Inefficiently return a vector of registered items
    unsigned int GetRegisteredItems(std::vector<Key>& l) const
    {
        unsigned int sz = l.size();
        l.resize(sz + i_registeredObjects.size());
        for (typename RegistryMapType::const_iterator iter = i_registeredObjects.begin(); iter != i_registeredObjects.end(); ++iter)
            l[sz++] = iter->first;
        return i_registeredObjects.size();
    }

    /// Return the map of registered items
    RegistryMapType const& GetRegisteredItems() const
    {
        return i_registeredObjects;
    }

    ObjectRegistry() { }
    ~ObjectRegistry()
    {
        for (typename RegistryMapType::iterator iter = i_registeredObjects.begin(); iter != i_registeredObjects.end(); ++iter)
            delete iter->second;
        i_registeredObjects.clear();
    }
private:
    RegistryMapType i_registeredObjects;
};

#endif