//-----------------------------------------------------------------------------
/// @file rf_term.ih
///
/// Refal+ term inline method implementation
//
//  $Source$
//  $Revision$
//  $Date$
//-----------------------------------------------------------------------------

#ifndef __rf_term_ih__
#define __rf_term_ih__

#include "rf_term.hh"
#include "rf_types.ih"
#include "rf_object.ih"
#include "rf_expr.hh"

namespace rfrt
{

using namespace rftype ;

inline Term::Term (term_class_t _class, unsigned _type)
{
  set_class(_class);
  set_type(_type);
}

inline Term::Term (uint16_t _c) :
  uint_data2 (_c)
{
  set_class(term_sym);
  set_type(type_char);
}

inline Term::Term (Object* _obj)
{
  set_class(term_obj);
  set_type(_obj->get_type());
  new(&uint_data2) Ref(_obj);
}

inline Term::~Term ()
{
#if 0
  if (is_ref()) {
//    Expr e(this);
//    e.get_mem_chunk()->dec_ref_count();
    MemoryChunk* m = get_mem_chunk();
    //
    // Decrement reference counter and destroy an object if it is zero
    if (m->dec_ref_count() == 0) {
      //
      // Walk through and decrement reference counters on childs
//      bool f = (data1 & REF_BIT) == 0 ? true : false;
      Expr::deref_childs(
        get_first(), (data1 & FLAT_BIT) != 0 ? get_last() : get_first(), m
      );
      //
      // Deallocate expression holder in memory
      MemoryChunk::destroy_instance(m);
    }
  }
#else
  (this->*dtor_funcs[get_class()])();
#endif
}

inline Term::Term (Term const& _t)
{
  (this->*ctor_funcs[_t.get_class()])(_t);
}

inline Term& Term::operator = (Term const& _t)
{
  if (_t != self) {
    this->~Term();
    new(this) Term(_t);
  }
  return self;
}

inline Expr Term::create_expr (size_t _len, int _align /* = 0 */)
{
  return Expr(_len, _align);
}

inline Expr Term::create_flat_expr (size_t _len, int _align /* = 0 */)
{
  Expr e(_len, _align);
  e.flags |= FLAT_BIT;
  return e;
}

inline bool Term::is_ref () const
{
  return get_class() == term_ref;
}

inline bool Term::is_sym () const
{
  return get_class() == term_sym;
}

inline bool Term::is_border () const
{
  return data1 == SYM_BORDER;
}

inline Term* Term::get_first () const
{
  return (Term*)(data1 & PTR_MASK);
}

inline Term* Term::get_last () const
{
//  return (Term*)(data2 & PTR_MASK);
  return (Term*)uint_data2;
}

inline unsigned Term::get_type () const
{
  return data1 >> TYPE_SHIFT;
}

inline void Term::set_type (unsigned _type)
{
  data1 = (_type << TYPE_SHIFT) | get_class();
}

inline term_class_t Term::get_class () const
{
  return (term_class_t)(data1 & CLASS_MASK);
}

inline void Term::set_class (term_class_t _class)
{
  data1 &= ~(CLASS_MASK);
  data1 |= _class;
}

inline MemoryChunk* Term::get_mem_chunk() const
{
  return static_cast<MemoryChunk*>(allocator.get_block(get_first()));
}

#if defined(RF_STORE_CHUNK_ORDER_IN_TERM)
inline unsigned get_order () const
{
  return Term::ORDER(data1 & ORDER1_MASK, data2 & ORDER2_MASK);
}
#endif

inline bool Term::operator == (Term const& _t) const
{
  term_class_t cl = get_class();
  //
  // If both terms have the same type...
  if (cl == _t.get_class()){
    //
    // ...compare them
    return (this->*eq_funcs[cl])(_t);
  } else {
    return false;
  }
}

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

inline bool Term::eq (
  Term const* _f1, Term const* _l1, Term const* _f2, Term const* _l2
)
{
  //
  // First compare term sequences lengths
  if ((_l1 - _f1) == (_l2 - _f2)) {
    //
    // If lengths are equal do per-term comparison
    for (; _f1 < _l1; _f1++, _f2++) {
      if (*_f1 != *_f2) return false;
    }
    return true;
  }
  return false;
}

inline bool Term::flat_eq (
  Term const* _f1, Term const* _f2, uintptr_t _len
)
{
  for (; _len--; _f1++, _f2++) {
    //
    // FIXME: Do not forget to do object comparison for compound symbols
    if (_f1->get_type() != _f2->get_type() || _f1->uint_data2 != _f2->uint_data2)
      return false;
  }
  return true;
}

inline Term::Term (Expr const& _expr) :
  data1 ((uintptr_t)_expr.get_first()),
  uint_data2 ((uintptr_t)_expr.get_last())
{
  set_class(term_ref);
  D(printf("+ term %p from expression %p(%p,%p,%p)\n",
           this, &_expr, _expr.first, _expr.last, _expr.mem_chunk);)
  data1 |= (_expr.get_flags() & FLAT_BIT);
  _expr.get_mem_chunk()->inc_ref_count();
}

inline Object& Term::get_object ()
{
  if (get_class() == term_obj) {
    Ref* r1 = (Ref*)(&uint_data2);
    return *(*r1);
  } else {
    FATAL("Term does not contain an object");
  }
}


inline Term::operator pxx::WString () const
{
  return (this->*to_string_funcs[get_class()])();
}

}

#endif // __rf_term_ih__