/*
 *  Main authors:
 *     Guido Tack <tack@gecode.org>
 *
 *  Copyright:
 *     Guido Tack, 2006
 *
 *  Last modified:
 *     $Date: 2006-08-17 16:58:48 +0200 (Thu, 17 Aug 2006) $ by $Author: tack $
 *     $Revision: 3548 $
 *
 *  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 {

  /*
   * Operations for set expression code
   *
   */

  forceinline
  SetExprCode::SetExprCode(void) : c(5), n(0) {}

  forceinline
  SetExprCode::SetExprCode(const SetExprCode& sc) : c(sc.c), n(sc.n) {}

  forceinline void
  SetExprCode::update(bool share, SetExprCode& sc) {
    n=sc.n; c.update(share, sc.c);
  }
  
  forceinline void
  SetExprCode::add(int i) {
    c.ensure(n+1);
    c[n] = i;
    n++;
  }

  forceinline int
  SetExprCode::size(void) const { return n; }

  forceinline int
  SetExprCode::operator[](int i) const { return c[i]; }

  /*
   * Operations for expressions
   *
   */

  forceinline
  SetExpr::SetExpr(void) : ax(NULL), sign(1) {}

  forceinline SetExpr
  operator-(const SetExpr& s) { return SetExpr(s, -1); }

  forceinline SetExpr
  operator||(const SetExpr& s, const SetExpr& t) {
    return SetExpr(s, 1, SetExpr::REL_UNION, t, 1);
  }

  forceinline SetExpr
  operator&&(const SetExpr& s, const SetExpr& t) {
    return SetExpr(s, 1, SetExpr::REL_INTER, t, 1);
  }

  forceinline SetExpr
  operator-(const SetExpr& s, const SetExpr& t) {
    return SetExpr(s, 1, SetExpr::REL_INTER, t, -1);
  }

  /**
   * \brief Range iterator for set expressions
   */
  class SetExprRanges {
  private:
    /// Reference-counted range iterators with virtual member functions
    class Iter;
    /// The actual iterator
    Iter *i;
    const SetExprRanges& operator=(const SetExprRanges&);
  public:
    /// \name Constructors and destructor
    //@{    
    /// Copy constructor
    SetExprRanges(const SetExprRanges&);
    /** Initialize with the views \a x, a set expression \a s,
     *  and a flag whether \a s is to be interpreted in a monotone or
     *  anti-monotone way
     */
    SetExprRanges(const ViewArray<Set::SetView>& x, SetExpr& s,
		  bool monotone);
    /** Initialize with the views \a x, a set expression code \a c,
     *  and a flag whether \a c is to be interpreted in a monotone or
     *  anti-monotone way
     */
    SetExprRanges(const ViewArray<Set::SetView>& x,
		  const SetExprCode& s,
		  bool monotone);
    /// Destructor
    ~SetExprRanges(void);
    //@}

    /// \name Iteration control
    //@{
    /// Move iterator to next range (if possible)
    bool operator()(void);
    /// Test whether iterator is still at a range or done
    void operator++(void);
    //@}

    /// \name Range access
    //@{
    /// Return smallest value of range
    int min(void) const;
    /// Return largest value of range
    int max(void) const;
    /// Return width of range (distance between minimum and maximum)
    unsigned int width(void) const;
    //@}
  };

  /**
   * \brief Reference-counted range iterators with virtual member functions
   *
   */
  class SetExprRanges::Iter {
  public:
    /// The actual iterator
    Gecode::Iter::Ranges::Virt::Iterator* i;
    /// Reference count
    int num;

    /// Construct from iterator
    Iter(Gecode::Iter::Ranges::Virt::Iterator*);
    /// Destructor
    ~Iter(void);
    /// Increment reference count
    void increment(void);
    /// Decrement reference count
    bool decrement(void);
  };

  forceinline
  SetExprRanges::Iter::Iter(Gecode::Iter::Ranges::Virt::Iterator* i0)
    : i(i0), num(1) {}
  
  forceinline
  SetExprRanges::Iter::~Iter(void) { delete i; }

  forceinline void
  SetExprRanges::Iter::increment(void) { ++num; }

  forceinline bool
  SetExprRanges::Iter::decrement(void) { return --num==0; }

  forceinline
  SetExprRanges::SetExprRanges(const SetExprRanges& s) : i(s.i) {
    i->increment();
  }

  forceinline
  SetExprRanges::~SetExprRanges(void) {
    if (i->decrement())
      delete i;
  }

  forceinline bool
  SetExprRanges::operator()(void) { return (*(i->i))(); }
  
  forceinline void
  SetExprRanges::operator++(void) { ++(*(i->i)); }

  forceinline int
  SetExprRanges::min(void) const { return i->i->min(); }

  forceinline int
  SetExprRanges::max(void) const { return i->i->max(); }

  forceinline unsigned int
  SetExprRanges::width(void) const { return i->i->width(); }

}

// STATISTICS: set-prop