/*
 * Project: MoleCuilder
 * Description: creates and alters molecular systems
 * Copyright (C)  2011 University of Bonn. All rights reserved.
 * Please see the LICENSE file or "Copyright notice" in builder.cpp for details.
 */

/*
 * LinkedCell_Controller.cpp
 *
 *  Created on: Nov 15, 2011
 *      Author: heber
 */

// include config.h
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "CodePatterns/MemDebug.hpp"

#include "Box.hpp"
#include "LinkedCell_Controller.hpp"
#include "LinkedCell_Model.hpp"
#include "LinkedCell_View.hpp"

#include "CodePatterns/Assert.hpp"

using namespace LinkedCell;

/** Constructor of class LinkedCell_Controller.
 *
 */
LinkedCell_Controller::LinkedCell_Controller(const Box &_domain) :
    domain(_domain)
{}

/** Destructor of class LinkedCell_Controller.
 *
 * Here, we free all LinkedCell_Model instances again.
 *
 */
LinkedCell_Controller::~LinkedCell_Controller()
{
  // remove all linked cell models
  for(MapEdgelengthModel::iterator iter = ModelsMap.begin();
      !ModelsMap.empty(); iter = ModelsMap.begin()) {
    delete iter->second;
    ModelsMap.erase(iter);
  }
}

/** Internal function to decide whether a suitable model is present or not.
 *
 * Here, the heuristic for deciding whether a new linked cell structure has to
 * be constructed or not is implemented.
 *
 * \note Dealing out a pointer is here (hopefully) safe because the function is
 * internal and we - inside this class - know what we are doing.
 *
 * @param distance edge length of the requested linked cell structure
 * @return NULL - there is no fitting LinkedCell_Model, else - pointer to instance
 */
const LinkedCell_Model *LinkedCell_Controller::getBestModel(const double distance) const
{
  for(MapEdgelengthModel::const_iterator iter = ModelsMap.begin();
      iter != ModelsMap.end(); ++iter) {
    // here, we use the heuristic
    if (true) {
      return iter->second;
    }
  }
  return NULL;
}

/** Returns the a suitable LinkedCell_Model contained in a LinkedCell_View
 *  for the requested \a distance.
 *
 * \sa getBestModel()
 *
 * @param distance edge length of the requested linked cell structure
 * @return LinkedCell_View wrapping the best LinkedCell_Model
 */
LinkedCell_View LinkedCell_Controller::getView(const double distance)
{
  // look for best instance
  const LinkedCell_Model *LCModel_best = getBestModel(distance);

  // construct new instance if none found
  if (LCModel_best == NULL) {
    LinkedCell_Model *LCModel_new = new LinkedCell_Model(distance, domain);
    std::pair< MapEdgelengthModel::iterator, bool> inserter =
        ModelsMap.insert( std::make_pair(distance, LCModel_new) );
    ASSERT(inserter.second,
        "LinkedCell_Controller::getView() - LinkedCell_Model instance with distance "
        +toString(distance)+" already present.");
    LinkedCell_View interface(const_cast<const LinkedCell_Model &>(*LCModel_new));
    return interface;
  } else {
    // construct interface and return
    LinkedCell_View interface(*LCModel_best);
    return interface;
  }
}