IResourcePool.h

#pragma once

#include "config.h"

#include <map>
#include <string>

namespace dawn
{
    template <class K, class V>
    class IResourcePool
    {
    public:
        IResourcePool()
        {
        }

        virtual ~IResourcePool()
        {
            ReleaseAllResources();
        }

        void ReleaseAllResources()
        {
            while (m_resources.begin() != m_resources.end()) {
                m_resources.erase(m_resources.begin());
            }
        }

        void ReleaseResource(K k)
        {
            typename CResourceMap::iterator it;
            it=m_resources.find(id(k));
            if (it != m_resources.end()) {
                m_resources.erase(it);
            }
        }

        V GetResource(K k)
        {
            typename CResourceMap::iterator it;
            V resource;
            std::string name = id(k);
            it=m_resources.find(name);

            if (it != m_resources.end() && IsResourceValid(k, it->second)) {
                resource = it->second;
            } else {
                resource = LoadResource(k);

#if RESOURCE_STORE_POLICY != RESOURCE_NEVER_STORE
                if (resource)
                    m_resources[name] = resource;
#endif
            }

            return resource;
        }

    protected:
        virtual std::string id(K k) = 0;
        virtual bool IsResourceValid(K k, V v) { return true; }
        virtual V LoadResource(K k) = 0;

        typedef std::map<std::string, V> CResourceMap;
        CResourceMap m_resources;
    };
}