// -*- mode: c++; c-indent-level: 4; c++-member-init-indent: 8; comment-column: 35; -*-

// "peoSyncIslandMig.h"

// (c) OPAC Team, LIFL, August 2005

/* This library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2 of the License, or (at your option) any later version.
   
   This library 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
   Lesser General Public License for more details.
   
   You should have received a copy of the GNU Lesser General Public
   License along with this library; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
   
   Contact: cahon@lifl.fr
*/

#ifndef __peoSyncIslandMig_h
#define __peoSyncIslandMig_h

#include <eoPeriodicContinue.h>

#include <queue>
#include <cassert>

#include <utils/eoUpdater.h>

#include <eoContinue.h>
#include <eoSelect.h>
#include <eoReplacement.h>
#include <eoPop.h>

#include "topo.h"
#include "thread.h"
#include "eoPop_comm.h"
#include "peo_debug.h"

template <class EOT> class peoSyncIslandMig : public Cooperative, public eoUpdater {

public :
  
  /* Ctor */
  peoSyncIslandMig (unsigned __freq,		   
		    eoSelect <EOT> & __select,
		    eoReplacement <EOT> & __replace,
		    Topology & __topo,
		    eoPop <EOT> & __from,
		    eoPop <EOT> & __to);
  
  void operator () ();

  void pack ();

  void unpack ();

  void notifySending ();
  
private :

  void emigrate ();

  void immigrate ();

  eoPeriodicContinue <EOT> cont;
  eoSelect <EOT> & select; /* The selection strategy */
  eoReplacement <EOT> & replace; /* The replacement strategy */
  Topology & topo; /* The neighboring topology */

  /* Source and target populations */
  eoPop <EOT> & from, & to; 
  
  /* Immigrants & emigrants in the queue */ 
  std :: queue <eoPop <EOT> > imm, em;

  std :: queue <Cooperative *> coop_em;
  
  sem_t sync;
};

template <class EOT> peoSyncIslandMig <EOT> :: peoSyncIslandMig (unsigned __freq,   
							       eoSelect <EOT> & __select,
							       eoReplacement <EOT> & __replace,
							       Topology & __topo,
							       eoPop <EOT> & __from,
							       eoPop <EOT> & __to
							       ) : cont (__freq),
								   select (__select),
								   replace (__replace),
								   topo (__topo),
								   from (__from),
								   to (__to) {
  __topo.add (* this);
  sem_init (& sync, 0, 0);
}

template <class EOT> void peoSyncIslandMig <EOT> :: pack () {

  lock ();  
  :: pack (coop_em.front () -> getKey ());
  :: pack (em.front ());
  coop_em.pop ();
  em.pop ();
  unlock ();
}

template <class EOT> void peoSyncIslandMig <EOT> :: unpack () {

  lock ();
  eoPop <EOT> mig;
  :: unpack (mig);
  imm.push (mig);  
  unlock ();
  sem_post (& sync);
}

template <class EOT> void peoSyncIslandMig <EOT> :: emigrate () {
  
  std :: vector <Cooperative *> in, out ;	
  topo.setNeighbors (this, in, out) ;
  
  for (unsigned i = 0; i < out.size (); i ++) {
    eoPop <EOT> mig;
    select (from, mig);
    em.push (mig);
    coop_em.push (out [i]);
    send (out [i]);
    printDebugMessage ("sending some emigrants.");
  }  
}


template <class EOT> void peoSyncIslandMig <EOT> :: immigrate () {
  
  lock ();    
  assert (imm.size ());
  replace (to, imm.front ()) ;
  imm.pop ();
  printDebugMessage ("receiving some immigrants.");
  unlock ();  
}

template <class EOT> void peoSyncIslandMig <EOT> :: operator () () {

  if (! cont (from)) {
    
    /* Sending emigrants */
    emigrate ();
    stop ();
    /* Sync. */
    sem_wait (& sync);
    getOwner () -> setActive ();
    /* Immigrants */
    immigrate ();
  }
}

template <class EOT> void peoSyncIslandMig <EOT> :: notifySending () {
  
  lock ();
  if (imm.empty ()) {
    printDebugMessage ("mode passif\n");
    getOwner () -> setPassive ();
  }  
  unlock ();
  resume ();
}
 
#endif