// Copyright (C) 2010, Guy Barrand. All rights reserved.
// See the file tools.license for terms.

#ifndef tools_sg_gstos
#define tools_sg_gstos

#include "render_manager"
#include <vector>
#include <ostream>

//#define TOOLS_SG_GSTOS_DEBUG

namespace tools {
namespace sg {

class gstos {
protected:
  gstos() {}
  virtual ~gstos() {clean_gstos();}
protected:
  gstos(const gstos&) {}
  gstos& operator=(const gstos& a_from) {
    if(&a_from==this) return *this;
    clean_gstos();
    return *this;
  }
public:
  size_t num_gstos() const {return m_gstos.size();}
protected:
  unsigned int get_tex_id(std::ostream& a_out,render_manager& a_mgr,const img_byte& a_img,bool a_NEAREST) {
    unsigned int _id = _find(&a_mgr);
    if(_id && !a_mgr.is_gsto_id_valid(_id)){
#ifdef TOOLS_SG_GSTOS_DEBUG
      a_out << "debug : tools::sg::gstos::get_tex_id : " << _id << " not valid." << std::endl;
#endif
      clean_gstos(&a_mgr);
      _id = 0;
    }
    if(!_id) {
#ifdef TOOLS_SG_GSTOS_DEBUG
      a_out << "debug : tools::sg::gstos::get_tex_id : create_texture ... " << std::endl;
#endif
      _id = a_mgr.create_texture(a_img,a_NEAREST);
#ifdef TOOLS_SG_GSTOS_DEBUG
      a_out << "debug : tools::sg::gstos::get_tex_id : create_texture : _id " << _id << "." << std::endl;
#endif
      if(!_id) {
        a_out << "tools::sg::gstos::get_tex_id :"
              << " render_manager.create_texture() failed."
              << std::endl;
      } else {
        m_gstos.push_back(std::pair<unsigned int,render_manager*>(_id,&a_mgr));
      }
    }
    return _id;
  }
protected:
  virtual unsigned int create_gsto(std::ostream&,render_manager&) {return 0;}

  unsigned int get_gsto_id(std::ostream& a_out,render_manager& a_mgr){
    unsigned int _id = _find(&a_mgr);
    if(_id && !a_mgr.is_gsto_id_valid(_id)){
#ifdef TOOLS_SG_GSTOS_DEBUG
      a_out << "debug : tools::sg::gstos::get_gsto_id : " << _id << " not valid." << std::endl;
#endif
      clean_gstos(&a_mgr);
      _id = 0;
    }
    if(!_id) {
#ifdef TOOLS_SG_GSTOS_DEBUG
      a_out << "debug : tools::sg::gstos::get_gsto_id : create_gsto ..." << std::endl;
#endif
      _id = create_gsto(a_out,a_mgr);
#ifdef TOOLS_SG_GSTOS_DEBUG
      a_out << "debug : tools::sg::gstos::get_gsto_id : create_gsto : _id " << _id << "." << std::endl;
#endif
      if(!_id) {
        // could be ok if there is no graphical data to load.
        //a_out << "tools::sg::gstos::get_gsto_id :"
        //      << " create_gsto() failed."
        //      << std::endl;
      } else {
        m_gstos.push_back(std::pair<unsigned int,render_manager*>(_id,&a_mgr));
      }
    }
    return _id;
  }
protected:
  void clean_gstos() {
    std::vector< std::pair<unsigned int,render_manager*> >::iterator it;
    for(it=m_gstos.begin();it!=m_gstos.end();){
      (*it).second->delete_gsto((*it).first);
      it = m_gstos.erase(it);
    }
  }
  void clean_gstos(render_manager* a_mgr) {
    std::vector< std::pair<unsigned int,render_manager*> >::iterator it;
    for(it=m_gstos.begin();it!=m_gstos.end();){
      if((*it).second==a_mgr) {
        (*it).second->delete_gsto((*it).first);
        it = m_gstos.erase(it);
      } else {
        it++;
      }
    }
  }
protected:
  unsigned int _find(render_manager* a_mgr) {
    std::vector< std::pair<unsigned int,render_manager*> >::iterator it;
    for(it=m_gstos.begin();it!=m_gstos.end();++it){
      if((*it).second==a_mgr) return (*it).first;
    }
    return 0;
  }

protected:
  std::vector< std::pair<unsigned int,render_manager*> > m_gstos;
};

}}

#endif