text: /* -*- mode: C++; c-basic-offset: 2; indent-tabs-mode: nil -*- */
  /*
   *  Main authors:
   *     Christian Schulte <schulte@gecode.org>
   *     Guido Tack <tack@gecode.org>
   *
   *  Copyright:
   *     Christian Schulte, 2006
   *     Guido Tack, 2011
   *
   *  Last modified:
   *     $Date$ by $Author$
   *     $Revision$
   *
   *  This file is part of Gecode, the generic constraint
   *  development environment:
   *     http://www.gecode.org
   *
   *  Permission is hereby granted, free of charge, to any person obtaining
   *  a copy of this software and associated documentation files (the
   *  "Software"), to deal in the Software without restriction, including
   *  without limitation the rights to use, copy, modify, merge, publish,
   *  distribute, sublicense, and/or sell copies of the Software, and to
   *  permit persons to whom the Software is furnished to do so, subject to
   *  the following conditions:
   *
   *  The above copyright notice and this permission notice shall be
   *  included in all copies or substantial portions of the Software.
   *
   *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
   *  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
   *  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
   *  NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
   *  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
   *  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
   *  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
   *
   */
  
  #include <gecode/int/channel.hh>
  
  namespace Gecode {
  
    void
    channel(Home home, const IntVarArgs& x, int xoff,
            const IntVarArgs& y, int yoff,
            IntConLevel icl) {
      using namespace Int;
      using namespace Channel;
      int n = x.size();
      if (n != y.size())
        throw ArgumentSizeMismatch("Int::channel");
      if (x.same(home) || y.same(home))
        throw ArgumentSame("Int::channel");
      Limits::check(xoff,"Int::channel");
      Limits::check(yoff,"Int::channel");
      if ((xoff < 0) || (yoff < 0))
        throw OutOfLimits("Int::channel");
      if (home.failed()) return;
      if (n == 0)
        return;
  
      if ((xoff < 2) && (yoff < 2) && (xoff == yoff)) {
        if (icl == ICL_DOM) {
          DomInfo<IntView,NoOffset<IntView> >* di = 
            static_cast<Space&>(home).
              alloc<DomInfo<IntView,NoOffset<IntView> > >(2*(n+xoff));
          for (int i=n; i--; ) {
            di[xoff+i    ].init(x[i],n+xoff);
            di[2*xoff+i+n].init(y[i],n+xoff);
          }
          if (xoff == 1) {
            IntVar x0(home,0,0);
            di[0].init(x0, n+xoff);
            IntVar y0(home,0,0);
            di[n+xoff].init(y0, n+xoff);
          }
          NoOffset<IntView> noff;
          if (x.same(home,y)) {
            GECODE_ES_FAIL((Dom<IntView,NoOffset<IntView>,true>
              ::post(home,n+xoff,di,noff,noff)));
          } else {
            GECODE_ES_FAIL((Dom<IntView,NoOffset<IntView>,false>
              ::post(home,n+xoff,di,noff,noff)));
          }
        } else {
          ValInfo<IntView>* vi = 
            static_cast<Space&>(home).alloc<ValInfo<IntView> >(2*(n+xoff));
          for (int i=n; i--; ) {
            vi[xoff+i    ].init(x[i],n+xoff);
            vi[2*xoff+i+n].init(y[i],n+xoff);
          }
          if (xoff == 1) {
            IntVar x0(home,0,0);
            vi[0].init(x0, n+xoff);
            IntVar y0(home,0,0);
            vi[n+xoff].init(y0, n+xoff);
          }
          NoOffset<IntView> noff;
          if (x.same(home,y)) {
            GECODE_ES_FAIL((Val<IntView,NoOffset<IntView>,true>
              ::post(home,n+xoff,vi,noff,noff)));
          } else {
            GECODE_ES_FAIL((Val<IntView,NoOffset<IntView>,false>
              ::post(home,n+xoff,vi,noff,noff)));
          }
        }
      } else {
        if (icl == ICL_DOM) {
          DomInfo<IntView,Offset>* di = 
            static_cast<Space&>(home).alloc<DomInfo<IntView,Offset> >(2*n);
          for (int i=n; i--; ) {
            di[i  ].init(x[i],n);
            di[i+n].init(y[i],n);
          }
          Offset ox(-xoff);
          Offset oy(-yoff);
          if (x.same(home,y)) {
            GECODE_ES_FAIL((Dom<IntView,Offset,true>
                            ::post(home,n,di,ox,oy)));
          } else {
            GECODE_ES_FAIL((Dom<IntView,Offset,false>
                            ::post(home,n,di,ox,oy)));
          }
        } else {
          ValInfo<IntView>* vi = 
            static_cast<Space&>(home).alloc<ValInfo<IntView> >(2*n);
          for (int i=n; i--; ) {
            vi[i  ].init(x[i],n);
            vi[i+n].init(y[i],n);
          }
          Offset ox(-xoff);
          Offset oy(-yoff);
          if (x.same(home,y)) {
            GECODE_ES_FAIL((Val<IntView,Offset,true>
                            ::post(home,n,vi,ox,oy)));
          } else {
            GECODE_ES_FAIL((Val<IntView,Offset,false>
                            ::post(home,n,vi,ox,oy)));
          }
        }
      }
  
    }
  
    void
    channel(Home home, const IntVarArgs& x, const IntVarArgs& y,
            IntConLevel icl) {
      channel(home, x, 0, y, 0, icl);
    }
    void
    channel(Home home, BoolVar x0, IntVar x1, IntConLevel) {
      using namespace Int;
      if (home.failed()) return;
      GECODE_ES_FAIL(Channel::LinkSingle::post(home,x0,x1));
    }
  
    void
    channel(Home home, const BoolVarArgs& x, IntVar y, int o,
            IntConLevel) {
      using namespace Int;
      if (x.same(home))
        throw ArgumentSame("Int::channel");
      Limits::check(o,"Int::channel");
      if (home.failed()) return;
      ViewArray<BoolView> xv(home,x);
      GECODE_ES_FAIL(Channel::LinkMulti::post(home,xv,y,o));
    }
  
  }
  
  // STATISTICS: int-post
  