/*********************                                                        */
/*! \file ecdata.cpp
 ** \verbatim
 ** Original author: Morgan Deters
 ** Major contributors: none
 ** Minor contributors (to current version): none
 ** This file is part of the CVC4 project.
 ** Copyright (c) 2009-2014  New York University and The University of Iowa
 ** See the file COPYING in the top-level source directory for licensing
 ** information.\endverbatim
 **
 ** \brief Implementation of equivalence class data for UF theory.
 **
 ** Implementation of equivalence class data for UF theory.  This is a
 ** context-dependent object.
 **/

#include "theory/uf/tim/ecdata.h"

using namespace CVC4;
using namespace CVC4::context;
using namespace CVC4::theory;
using namespace CVC4::theory::uf;
using namespace CVC4::theory::uf::tim;

ECData::ECData(Context * context, TNode n) :
  ContextObj(context),
  d_find(this),
  d_rep(n),
  d_watchListSize(0),
  d_first(NULL),
  d_last(NULL) {
}

bool ECData::isClassRep() {
  return this == this->d_find;
}

void ECData::addPredecessor(TNode n) {
  Assert(isClassRep());

  makeCurrent();

  Link * newPred = new(getCMM()) Link(getContext(), n, d_first);
  d_first = newPred;
  if(d_last == NULL) {
    d_last = newPred;
  }

  ++d_watchListSize;
}

ContextObj* ECData::save(ContextMemoryManager* pCMM) {
  return new(pCMM) ECData(*this);
}

void ECData::restore(ContextObj* pContextObj) {
  ECData* data = (ECData*)pContextObj;
  d_find = data->d_find;
  d_first = data->d_first;
  d_last = data->d_last;
  d_rep = data->d_rep;
  d_watchListSize = data->d_watchListSize;
}

Node ECData::getRep() {
  return d_rep;
}

unsigned ECData::getWatchListSize() {
  return d_watchListSize;
}

void ECData::setFind(ECData * ec) {
  makeCurrent();
  d_find = ec;
}

ECData* ECData::getFind() {
  return d_find;
}

Link* ECData::getFirst() {
  return d_first;
}

void ECData::takeOverDescendantWatchList(ECData* nslave, ECData* nmaster) {
  Assert(nslave != nmaster);
  Assert(nslave->getFind() == nmaster);

  nmaster->makeCurrent();

  nmaster->d_watchListSize += nslave->d_watchListSize;

  if(nmaster->d_first == NULL) {
    nmaster->d_first = nslave->d_first;
    nmaster->d_last = nslave->d_last;
  } else if(nslave->d_first != NULL) {
    Link* currLast = nmaster->d_last;
    currLast->d_next = nslave->d_first;
    nmaster->d_last = nslave->d_last;
  }
}