/*

  KLayout Layout Viewer
  Copyright (C) 2006-2017 Matthias Koefferlein

  This program 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.

  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 General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

*/


#include "dbLibraryManager.h"
#include "dbLibrary.h"
#include "dbCommon.h"

#include "tlAssert.h"
#include "tlStaticObjects.h"
#include "tlClassRegistry.h"

#include <memory>

namespace tl
{
  template<> DB_PUBLIC tl::Registrar<db::Library> *tl::Registrar<db::Library>::instance = 0;
}

namespace db
{

static LibraryManager *sp_instance (0);

LibraryManager &
LibraryManager::instance ()
{
  if (sp_instance == 0) {
    sp_instance = new LibraryManager ();
    tl::StaticObjects::reg (&sp_instance);
  }
  return *sp_instance;
}

bool LibraryManager::initialized () 
{
  return sp_instance != 0;
}

LibraryManager::LibraryManager ()
{
  // handle auto-registered libraries:
  for (tl::Registrar<db::Library>::iterator l = tl::Registrar<db::Library>::begin (); l != tl::Registrar<db::Library>::end (); ++l) {
    // take library - no other one will need it
    register_lib (l.take ());
  }
}

LibraryManager::~LibraryManager ()
{
  clear ();
}

std::pair<bool, lib_id_type> 
LibraryManager::lib_by_name (const std::string &name) const
{
  iterator l = m_lib_by_name.find (name);
  if (l == m_lib_by_name.end ()) {
    return std::make_pair (false, lib_id_type (0));
  } else {
    return std::make_pair (true, l->second);
  }
}

void
LibraryManager::delete_lib (Library *library)
{
  if (!library) {
    return;
  }

  m_lib_by_name.erase (library->get_name ());

  for (lib_id_type id = 0; id < m_libs.size (); ++id) {
    if (m_libs [id] == library) {
      library->remap_to (0);
      delete library;
      m_libs [id] = 0;
    }
  }
}

lib_id_type 
LibraryManager::register_lib (Library *library)
{
  library->keep (); //  marks the library owned by the C++ side of GSI

  lib_id_type id;
  for (id = 0; id < m_libs.size (); ++id) {
    if (m_libs [id] == 0) {
      break;
    }
  }

  if (id == m_libs.size ()) {
    m_libs.push_back (library);
  } else {
    m_libs [id] = library;
  }

  library->set_id (id);

  //  if the new library replaces the old one, remap existing library proxies before deleting the library
  lib_name_map::iterator ln = m_lib_by_name.find (library->get_name ());
  if (ln != m_lib_by_name.end () && m_libs [ln->second]) {
    m_libs [ln->second]->remap_to (library);
    delete m_libs [ln->second];
    m_libs [ln->second] = 0;
  }

  m_lib_by_name.insert (std::make_pair (library->get_name (), id)).first->second = id;

  changed_event ();

  return id;
}

Library *
LibraryManager::lib (lib_id_type id) const
{
  if (id >= m_libs.size ()) {
    return 0;
  } else {
    return m_libs [id];
  }
}

void
LibraryManager::clear ()
{
  if (m_libs.empty ()) {
    return;
  }

  //  empty the library table before we delete them - this avoid accesses to invalid libraries while doing so.    
  std::vector<Library *> libs;
  libs.swap (m_libs);
  m_lib_by_name.clear ();

  for (std::vector<Library *>::iterator l = libs.begin (); l != libs.end (); ++l) {
    if (*l) {
      delete *l;
    }
  }

  changed_event ();
}

}