/*
 *  Main authors:
 *     Christian Schulte <schulte@gecode.org>
 *
 *  Copyright:
 *     Christian Schulte, 2003
 *
 *  Last modified:
 *     $Date: 2006-09-07 11:57:31 +0200 (Thu, 07 Sep 2006) $ by $Author: schulte $
 *     $Revision: 3612 $
 *
 *  This file is part of Gecode, the generic constraint
 *  development environment:
 *     http://www.gecode.org
 *
 *  See the file "LICENSE" for information on usage and
 *  redistribution of this file, and for a
 *     DISCLAIMER OF ALL WARRANTIES.
 *
 */

namespace Gecode { namespace Int { namespace Count {

  /*
   * General baseclass
   *
   */

  template <class VX, class VY, class VZ, bool shr>
  BaseView<VX,VY,VZ,shr>::BaseView(Space* home,
				   ViewArray<VX>& x0, VY y0, VZ z0, int c0)
    : Propagator(home), x(x0), y(y0), z(z0), c(c0) {
    x.subscribe(home,this,PC_INT_DOM);
    y.subscribe(home,this,PC_INT_DOM);
    z.subscribe(home,this,PC_INT_BND);
  }

  template <class VX, class VY, class VZ, bool shr>
  inline
  BaseView<VX,VY,VZ,shr>::BaseView(Space* home, bool share,
				   BaseView<VX,VY,VZ,shr>& p)
    : Propagator(home,shr,p), c(p.c) {
    x.update(home,share,p.x);
    y.update(home,share,p.y);
    z.update(home,share,p.z);
  }

  template <class VX, class VY, class VZ, bool shr>
  PropCost
  BaseView<VX,VY,VZ,shr>::cost(void) const {
    return cost_lo(x.size()+1, PC_LINEAR_LO);
  }

  template <class VX, class VY, class VZ, bool shr>
  size_t
  BaseView<VX,VY,VZ,shr>::dispose(Space* home) {
    assert(!home->failed());
    x.cancel(home,this,PC_INT_DOM);
    y.cancel(home,this,PC_INT_DOM);
    z.cancel(home,this,PC_INT_BND);
    (void) Propagator::dispose(home);
    return sizeof(*this);
  }

  template <class VX, class VY, class VZ, bool shr>
  forceinline void
  BaseView<VX,VY,VZ,shr>::count(Space* home) {
    int n = x.size();
    for (int i=n; i--; )
      switch (holds(x[i],y)) {
      case RT_FALSE:
	x[i].cancel(home,this,PC_INT_DOM); x[i]=x[--n];
	break;
      case RT_TRUE:
	x[i].cancel(home,this,PC_INT_DOM); x[i]=x[--n];
	c--;
	break;
      case RT_MAYBE:
	break;
      default: 
	GECODE_NEVER;
      }
    x.size(n);
  }

  template <class VX, class VY, class VZ, bool shr>
  forceinline int
  BaseView<VX,VY,VZ,shr>::atleast(void) const {
    return -c;
  }

  template <class VX, class VY, class VZ, bool shr>
  forceinline int
  BaseView<VX,VY,VZ,shr>::atmost(void) const {
    return x.size()-c;
  }

  template <class VX, class VY, class VZ, bool shr>
  inline bool
  BaseView<VX,VY,VZ,shr>::sharing(const ViewArray<VX>& x,
				  const VY& y, const VZ& z) {
    if (shared(y,z))
      return true;
    for (int i = x.size(); i--; )
      if (shared(x[i],z))
	return true;
    return false;
  }

  /*
   * Equality
   *
   */

  template <class VX, class VY, class VZ, bool shr>
  forceinline
  EqView<VX,VY,VZ,shr>::EqView(Space* home, 
			       ViewArray<VX>& x, VY y, VZ z, int c)
    : BaseView<VX,VY,VZ,shr>(home,x,y,z,c) {}

  template <class VX, class VY, class VZ, bool shr>
  ExecStatus
  EqView<VX,VY,VZ,shr>::post(Space* home, 
			     ViewArray<VX>& x, VY y, VZ z, int c) {
    if (z.assigned())
      return EqInt<VX,VY>::post(home,x,y,z.val()+c);
    if (sharing(x,y,z))
      (void) new (home) EqView<VX,VY,VZ,true>(home,x,y,z,c);
    else
      (void) new (home) EqView<VX,VY,VZ,false>(home,x,y,z,c);
    return ES_OK;
  }

  template <class VX, class VY, class VZ, bool shr>
  forceinline
  EqView<VX,VY,VZ,shr>::EqView(Space* home, bool share, 
			       EqView<VX,VY,VZ,shr>& p)
    : BaseView<VX,VY,VZ,shr>(home,share,p) {}

  template <class VX, class VY, class VZ, bool shr>
  Actor*
  EqView<VX,VY,VZ,shr>::copy(Space* home, bool share) {
    return new (home) EqView<VX,VY,VZ,shr>(home,share,*this);
  }

  template <class VX, class VY, class VZ, bool shr>
  ExecStatus
  EqView<VX,VY,VZ,shr>::propagate(Space* home) {
    count(home);

    GECODE_ME_CHECK(z.gq(home,atleast()));
    GECODE_ME_CHECK(z.lq(home,atmost()));

    if (z.assigned()) {
      if (z.val() == atleast())
	return post_false(home,x,y);
      if (z.val() == atmost())
	return post_true(home,x,y);
      GECODE_ES_CHECK((EqInt<VX,VY>::post(home,x,y,z.val()+c)));
      return ES_SUBSUMED;
    }
    return shr ? ES_NOFIX : ES_FIX;
  }




  /*
   * Disequality
   *
   */

  template <class VX, class VY, class VZ, bool shr>
  forceinline
  NqView<VX,VY,VZ,shr>::NqView(Space* home, 
			       ViewArray<VX>& x, VY y, VZ z, int c)
    : BaseView<VX,VY,VZ,shr>(home,x,y,z,c) {}

  template <class VX, class VY, class VZ, bool shr>
  ExecStatus
  NqView<VX,VY,VZ,shr>::post(Space* home, 
			     ViewArray<VX>& x, VY y, VZ z, int c) {
    if (z.assigned())
      return NqInt<VX,VY>::post(home,x,y,z.val()+c);
    (void) new (home) NqView<VX,VY,VZ,shr>(home,x,y,z,c);
    return ES_OK;
  }

  template <class VX, class VY, class VZ, bool shr>
  forceinline
  NqView<VX,VY,VZ,shr>::NqView(Space* home, bool share, 
			       NqView<VX,VY,VZ,shr>& p)
    : BaseView<VX,VY,VZ,shr>(home,share,p) {}

  template <class VX, class VY, class VZ, bool shr>
  Actor*
  NqView<VX,VY,VZ,shr>::copy(Space* home, bool share) {
    return new (home) NqView<VX,VY,VZ,shr>(home,share,*this);
  }

  template <class VX, class VY, class VZ, bool shr>
  ExecStatus
  NqView<VX,VY,VZ,shr>::propagate(Space* home) {
    count(home);
    if (atleast() == atmost()) {
      GECODE_ME_CHECK(z.nq(home,atleast()));
      return ES_SUBSUMED;
    }
    if (z.max() < atleast())
      return ES_SUBSUMED;
    if (z.min() > atmost())
      return ES_SUBSUMED;
    if (z.assigned()) {
      GECODE_ES_CHECK((NqInt<VX,VY>::post(home,x,y,z.val()+c)));
      return ES_SUBSUMED;
    }
    return ES_FIX;
  }



  /*
   * Less or equal
   *
   */

  template <class VX, class VY, class VZ, bool shr>
  forceinline
  LqView<VX,VY,VZ,shr>::LqView(Space* home, ViewArray<VX>& x, 
			       VY y, VZ z, int c)
    : BaseView<VX,VY,VZ,shr>(home,x,y,z,c) {}

  template <class VX, class VY, class VZ, bool shr>
  ExecStatus
  LqView<VX,VY,VZ,shr>::post(Space* home, ViewArray<VX>& x, 
			     VY y, VZ z, int c) {
    if (z.assigned())
      return LqInt<VX,VY>::post(home,x,y,z.val()+c);
    if (sharing(x,y,z))
      (void) new (home) LqView<VX,VY,VZ,true>(home,x,y,z,c);
    else
      (void) new (home) LqView<VX,VY,VZ,false>(home,x,y,z,c);
    return ES_OK;
  }

  template <class VX, class VY, class VZ, bool shr>
  forceinline
  LqView<VX,VY,VZ,shr>::LqView(Space* home, bool share, 
			       LqView<VX,VY,VZ,shr>& p)
    : BaseView<VX,VY,VZ,shr>(home,share,p) {}

  template <class VX, class VY, class VZ, bool shr>
  Actor*
  LqView<VX,VY,VZ,shr>::copy(Space* home, bool share) {
    return new (home) LqView<VX,VY,VZ,shr>(home,share,*this);
  }

  template <class VX, class VY, class VZ, bool shr>
  ExecStatus
  LqView<VX,VY,VZ,shr>::propagate(Space* home) {
    count(home);
    GECODE_ME_CHECK(z.gq(home,atleast()));
    if (z.max() == atleast())
      return post_false(home,x,y);
    if (x.size() == 0)
      return ES_SUBSUMED;
    if (z.assigned()) {
      GECODE_ES_CHECK((LqInt<VX,VY>::post(home,x,y,z.val()+c)));
      return ES_SUBSUMED;
    }
    return shr ? ES_NOFIX : ES_FIX;
  }



  /*
   * Greater or equal
   *
   */

  template <class VX, class VY, class VZ, bool shr>
  forceinline
  GqView<VX,VY,VZ,shr>::GqView(Space* home, ViewArray<VX>& x, VY y, VZ z, int c)
    : BaseView<VX,VY,VZ,shr>(home,x,y,z,c) {}

  template <class VX, class VY, class VZ, bool shr>
  ExecStatus
  GqView<VX,VY,VZ,shr>::post(Space* home, 
			     ViewArray<VX>& x, VY y, VZ z, int c) {
    if (z.assigned())
      return GqInt<VX,VY>::post(home,x,y,z.val()+c);
    if (sharing(x,y,z))
      (void) new (home) GqView<VX,VY,VZ,true>(home,x,y,z,c);
    else
      (void) new (home) GqView<VX,VY,VZ,false>(home,x,y,z,c);
    return ES_OK;
  }

  template <class VX, class VY, class VZ, bool shr>
  forceinline
  GqView<VX,VY,VZ,shr>::GqView(Space* home, bool share, 
			       GqView<VX,VY,VZ,shr>& p)
    : BaseView<VX,VY,VZ,shr>(home,share,p) {}

  template <class VX, class VY, class VZ, bool shr>
  Actor*
  GqView<VX,VY,VZ,shr>::copy(Space* home, bool share) {
    return new (home) GqView<VX,VY,VZ,shr>(home,share,*this);
  }

  template <class VX, class VY, class VZ, bool shr>
  ExecStatus
  GqView<VX,VY,VZ,shr>::propagate(Space* home) {
    count(home);

    GECODE_ME_CHECK(z.lq(home,atmost()));

    if (z.min() == atmost())
      return post_true(home,x,y);
    if (x.size() == 0)
      return ES_SUBSUMED;
    if (z.assigned()) {
      GECODE_ES_CHECK((GqInt<VX,VY>::post(home,x,y,z.val()+c)));
      return ES_SUBSUMED;
    }
    return shr ? ES_NOFIX : ES_FIX;
  }

}}}

// STATISTICS: int-prop