asset/meta.hpp

Go to the documentation of this file.

/*
  META.hpp  -  key abstraction: metadata and organisational asset

   Copyright (C)
     2008,            Hermann Vosseler <Ichthyostega@web.de>

  **Lumiera** is free software; you can redistribute it and/or modify it
  under the terms of the GNU General Public License as published by the
  Free Software Foundation; either version 2 of the License, or (at your
  option) any later version. See the file COPYING for further details.

*/


#ifndef ASSET_META_H
#define ASSET_META_H

#include "steam/asset.hpp"
#include "steam/asset/struct-scheme.hpp"
#include "lib/idi/entry-id.hpp"
#include "lib/nocopy.hpp"


namespace steam {
namespace asset {
  
  class Meta;
  class MetaFactory;
  
  
  template<>
  class ID<Meta> : public ID<Asset>
    {
    public:
      ID (HashVal id);
      ID (const Meta&);
    };
  
  namespace meta {
    
    class Descriptor
      {
      public:
        virtual ~Descriptor();  
      };
      
      template<class MA>
      struct Builder;
  }
  
  
  class Meta
    : public Asset
    , public meta::Descriptor
    {
    public:
      static MetaFactory create;
      
      virtual const ID<Meta>& getID()  const
        {
          return static_cast<const ID<Meta>& > (Asset::getID());
        }
      
    protected:
      Meta (Asset::Ident const& idi)
        : Asset{idi}
        { }
      
      template<typename TY>
      Meta (lib::idi::EntryID<TY> const& nameID)
        : Meta{idi::getAssetIdent (nameID, META)}
        { }
      
//    friend class MetaFactory;  ///////////////////////////////////TODO still necessary?
    };
    
    
    // definition of ID<Meta> ctors is possible now,
   //  after providing full definition of class Meta
  
  inline ID<Meta>::ID(HashVal id)       : ID<Asset> (id)           {};
  inline ID<Meta>::ID(const Meta& meta) : ID<Asset> (meta.getID()) {};
  
  typedef lib::P<Meta> PMeta;
  
  
  
  class MetaFactory
    : util::NonCopyable
    {
    public:
      typedef lib::P<asset::Meta> PType;
      
      template<class MA>
      meta::Builder<MA> operator() (lib::idi::EntryID<MA> elementIdentity);
      
      template<class MA>
      meta::Builder<MA> operator() (meta::Descriptor const& prototype, lib::idi::EntryID<MA> elementIdentity);
      
    };
  
  
  
  
}} // namespace steam::asset
#endif