/*
 * This file is part of the Cforall project
 *
 * $Id: Cost.h,v 1.2 2003/01/27 14:46:59 rcbilson Exp $
 *
 */

#ifndef RESOLVEXPR_COST_H
#define RESOLVEXPR_COST_H

#include <iostream>

namespace ResolvExpr {

class Cost
{
public:
  Cost();
  Cost( int unsafe, int poly, int safe );
  
  void incUnsafe( int inc = 1 );
  void incPoly( int inc = 1 );
  void incSafe( int inc = 1 );
  
  Cost operator+( const Cost &other ) const;
  Cost operator-( const Cost &other ) const;
  Cost &operator+=( const Cost &other );
  bool operator<( const Cost &other ) const;
  bool operator==( const Cost &other ) const;
  bool operator!=( const Cost &other ) const;
  friend std::ostream &operator<<( std::ostream &os, const Cost &cost );
  
  static const Cost zero;
  static const Cost infinity;
  
private:
  int compare( const Cost &other ) const;

  int unsafe;
  int poly;
  int safe;
};

inline
Cost::Cost()
  : unsafe( 0 ), poly( 0 ), safe( 0 )
{
}

inline
Cost::Cost( int unsafe, int poly, int safe )
  : unsafe( unsafe ), poly( poly ), safe( safe )
{
}

inline void 
Cost::incUnsafe( int inc )
{
  unsafe += inc;
}

inline void 
Cost::incPoly( int inc )
{
  unsafe += inc;
}

inline void 
Cost::incSafe( int inc )
{
  unsafe += inc;
}

inline Cost 
Cost::operator+( const Cost &other ) const
{
  return Cost( unsafe + other.unsafe, poly + other.poly, safe + other.safe );
}

inline Cost 
Cost::operator-( const Cost &other ) const
{
  return Cost( unsafe - other.unsafe, poly - other.poly, safe - other.safe );
}

inline Cost &
Cost::operator+=( const Cost &other )
{
   unsafe += other.unsafe;
   poly += other.poly;
   safe += other.safe;
   return *this;
}

inline bool 
Cost::operator<( const Cost &other ) const
{
  if( *this == infinity ) return false;
  if( other == infinity ) return true;
  if( unsafe > other.unsafe ) {
    return false;
  } else if( unsafe < other.unsafe ) {
    return true;
  } else if( poly > other.poly ) {
    return false;
  } else if( poly < other.poly ) {
    return true;
  } else if( safe > other.safe ) {
    return false;
  } else if( safe < other.safe ) {
    return true;
  } else {
    return false;
  }
}

inline bool 
Cost::operator==( const Cost &other ) const
{
  return unsafe == other.unsafe
         && poly == other.poly
         && safe == other.safe;
}

inline bool 
Cost::operator!=( const Cost &other ) const
{
  return !( *this == other );
}

inline std::ostream &
operator<<( std::ostream &os, const Cost &cost )
{
  os << "( " << cost.unsafe << ", " << cost.poly << ", " << cost.safe << " )";
  return os;
}

} // namespace ResolvExpr

#endif /* #ifndef RESOLVEXPR_COST_H */