/*
 * This file is part of the AzerothCore Project. See AUTHORS file for Copyright information
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Affero General Public License as published by the
 * Free Software Foundation; either version 3 of the License, or (at your
 * option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program. If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef ACORE_OBJECTREGISTRY_H
#define ACORE_OBJECTREGISTRY_H

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

/** 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
