/*
 *  Main authors:
 *     Christian Schulte <schulte@gecode.org>
 *
 *  Copyright:
 *     Christian Schulte, 2003
 *
 *  Last modified:
 *     $Date: 2006-08-04 16:03:26 +0200 (Fri, 04 Aug 2006) $ by $Author: schulte $
 *     $Revision: 3512 $
 *
 *  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 Linear {

  /*
   * Ternary linear propagators
   *
   */
  template <class Val, class A, class B, class C, PropCond pc>
  forceinline
  LinTer<Val,A,B,C,pc>::LinTer(Space* home, A y0, B y1, C y2, Val c0)
    : Propagator(home), x0(y0), x1(y1), x2(y2), c(c0) {
    x0.subscribe(home,this,pc);
    x1.subscribe(home,this,pc);
    x2.subscribe(home,this,pc);
  }

  template <class Val, class A, class B, class C, PropCond pc>
  forceinline
  LinTer<Val,A,B,C,pc>::LinTer(Space* home, bool share,
			       LinTer<Val,A,B,C,pc>& p)
    : Propagator(home,share,p), c(p.c) {
    x0.update(home,share,p.x0);
    x1.update(home,share,p.x1);
    x2.update(home,share,p.x2);
  }

  template <class Val, class A, class B, class C, PropCond pc>
  forceinline
  LinTer<Val,A,B,C,pc>::LinTer(Space* home, bool share, Propagator& p,
			       A y0, B y1, C y2, Val c0)
    : Propagator(home,share,p), c(c0) {
    x0.update(home,share,y0);
    x1.update(home,share,y1);
    x2.update(home,share,y2);
  }

  template <class Val, class A, class B, class C, PropCond pc>
  PropCost
  LinTer<Val,A,B,C,pc>::cost(void) const {
    return PC_TERNARY_LO;
  }

  template <class Val, class A, class B, class C, PropCond pc>
  size_t
  LinTer<Val,A,B,C,pc>::dispose(Space* home) {
    assert(!home->failed());
    x0.cancel(home,this,pc);
    x1.cancel(home,this,pc);
    x2.cancel(home,this,pc);
    (void) Propagator::dispose(home);
    return sizeof(*this);
  }

  /*
   * Equality propagator
   *
   */

  template <class Val, class A, class B, class C>
  forceinline
  EqTer<Val,A,B,C>::EqTer(Space* home, A x0, B x1, C x2, Val c)
    : LinTer<Val,A,B,C,PC_INT_BND>(home,x0,x1,x2,c) {}

  template <class Val, class A, class B, class C>
  ExecStatus
  EqTer<Val,A,B,C>::post(Space* home, A x0, B x1, C x2, Val c) {
    (void) new (home) EqTer<Val,A,B,C>(home,x0,x1,x2,c);
    return ES_OK;
  }


  template <class Val, class A, class B, class C>
  forceinline
  EqTer<Val,A,B,C>::EqTer(Space* home, bool share, EqTer<Val,A,B,C>& p)
    : LinTer<Val,A,B,C,PC_INT_BND>(home,share,p) {}

  template <class Val, class A, class B, class C>
  forceinline
  EqTer<Val,A,B,C>::EqTer(Space* home, bool share, Propagator& p,
			  A x0, B x1, C x2, Val c)
    : LinTer<Val,A,B,C,PC_INT_BND>(home,share,p,x0,x1,x2,c) {}

  template <class Val, class A, class B, class C>
  Actor*
  EqTer<Val,A,B,C>::copy(Space* home, bool share) {
    return new (home) EqTer<Val,A,B,C>(home,share,*this);
  }

  /// Describe which view has been modified how
  enum TerMod {
    TM_X0_MIN = 1<<0,
    TM_X0_MAX = 1<<1,
    TM_X1_MIN = 1<<2,
    TM_X1_MAX = 1<<3,
    TM_X2_MIN = 1<<4,
    TM_X2_MAX = 1<<5,
    TM_ALL    = TM_X0_MIN|TM_X0_MAX|TM_X1_MIN|TM_X1_MAX|TM_X2_MIN|TM_X2_MAX
  };

#define GECODE_INT_PV(CASE,TELL,UPDATE)		\
  if (bm & (CASE)) {				\
    bm -= (CASE); ModEvent me = (TELL);		\
    if (me_failed(me))   return ES_FAILED;	\
    if (me_modified(me)) bm |= (UPDATE);	\
  }

  template <class Val, class A, class B, class C>
  ExecStatus
  EqTer<Val,A,B,C>::propagate(Space* home) {
    int bm = TM_ALL;
    do {
      GECODE_INT_PV(TM_X0_MIN, x0.gq(home,c-x1.max()-x2.max()),
		    TM_X1_MAX | TM_X2_MAX);
      GECODE_INT_PV(TM_X1_MIN, x1.gq(home,c-x0.max()-x2.max()),
		    TM_X0_MAX | TM_X2_MAX);
      GECODE_INT_PV(TM_X2_MIN, x2.gq(home,c-x0.max()-x1.max()),
		    TM_X0_MAX | TM_X1_MAX);
      GECODE_INT_PV(TM_X0_MAX, x0.lq(home,c-x1.min()-x2.min()),
		    TM_X1_MIN | TM_X2_MIN);
      GECODE_INT_PV(TM_X1_MAX, x1.lq(home,c-x0.min()-x2.min()),
		    TM_X0_MIN | TM_X2_MIN);
      GECODE_INT_PV(TM_X2_MAX, x2.lq(home,c-x0.min()-x1.min()),
		    TM_X0_MIN | TM_X1_MIN);
    } while (bm);
    return (x0.assigned() && x1.assigned()) ? ES_SUBSUMED : ES_FIX;
  }

#undef GECODE_INT_PV



  /*
   * Disequality propagator
   *
   */

  template <class Val, class A, class B, class C>
  forceinline
  NqTer<Val,A,B,C>::NqTer(Space* home, A x0, B x1, C x2, Val c)
    : LinTer<Val,A,B,C,PC_INT_VAL>(home,x0,x1,x2,c) {}

  template <class Val, class A, class B, class C>
  ExecStatus
  NqTer<Val,A,B,C>::post(Space* home, A x0, B x1, C x2, Val c) {
    (void) new (home) NqTer<Val,A,B,C>(home,x0,x1,x2,c);
    return ES_OK;
  }


  template <class Val, class A, class B, class C>
  forceinline
  NqTer<Val,A,B,C>::NqTer(Space* home, bool share, NqTer<Val,A,B,C>& p)
    : LinTer<Val,A,B,C,PC_INT_VAL>(home,share,p) {}

  template <class Val, class A, class B, class C>
  Actor*
  NqTer<Val,A,B,C>::copy(Space* home, bool share) {
    return new (home) NqTer<Val,A,B,C>(home,share,*this);
  }

  template <class Val, class A, class B, class C>
  forceinline
  NqTer<Val,A,B,C>::NqTer(Space* home, bool share, Propagator& p,
			  A x0, B x1, C x2, Val c)
    : LinTer<Val,A,B,C,PC_INT_VAL>(home,share,p,x0,x1,x2,c) {}


  template <class Val, class A, class B, class C>
  ExecStatus
  NqTer<Val,A,B,C>::propagate(Space* home) {
    if (x0.assigned() && x1.assigned()) {
      GECODE_ME_CHECK(x2.nq(home,c-x0.val()-x1.val()));
      return ES_SUBSUMED;
    }
    if (x0.assigned() && x2.assigned()) {
      GECODE_ME_CHECK(x1.nq(home,c-x0.val()-x2.val()));
      return ES_SUBSUMED;
    }
    if (x1.assigned() && x2.assigned()) {
      GECODE_ME_CHECK(x0.nq(home,c-x1.val()-x2.val()));
      return ES_SUBSUMED;
    }
    return ES_FIX;
  }



  /*
   * Inequality propagator
   *
   */

  template <class Val, class A, class B, class C>
  forceinline
  LqTer<Val,A,B,C>::LqTer(Space* home, A x0, B x1, C x2, Val c)
    : LinTer<Val,A,B,C,PC_INT_BND>(home,x0,x1,x2,c) {}

  template <class Val, class A, class B, class C>
  ExecStatus
  LqTer<Val,A,B,C>::post(Space* home, A x0, B x1, C x2, Val c) {
    (void) new (home) LqTer<Val,A,B,C>(home,x0,x1,x2,c);
    return ES_OK;
  }


  template <class Val, class A, class B, class C>
  forceinline
  LqTer<Val,A,B,C>::LqTer(Space* home, bool share, LqTer<Val,A,B,C>& p)
    : LinTer<Val,A,B,C,PC_INT_BND>(home,share,p) {}

  template <class Val, class A, class B, class C>
  Actor*
  LqTer<Val,A,B,C>::copy(Space* home, bool share) {
    return new (home) LqTer<Val,A,B,C>(home,share,*this);
  }

  template <class Val, class A, class B, class C>
  forceinline
  LqTer<Val,A,B,C>::LqTer(Space* home, bool share, Propagator& p,
			  A x0, B x1, C x2, Val c)
    : LinTer<Val,A,B,C,PC_INT_BND>(home,share,p,x0,x1,x2,c) {}

  template <class Val, class A, class B, class C>
  ExecStatus
  LqTer<Val,A,B,C>::propagate(Space* home) {
    GECODE_ME_CHECK(x0.lq(home,c-x1.min()-x2.min()));
    GECODE_ME_CHECK(x1.lq(home,c-x0.min()-x2.min()));
    GECODE_ME_CHECK(x2.lq(home,c-x0.min()-x1.min()));
    return (x0.max()+x1.max()+x2.max() <= c) ? ES_SUBSUMED : ES_FIX;
  }

}}}

// STATISTICS: int-prop