/****************************************
*  Computer Algebra System SINGULAR     *
****************************************/
/***************************************************************
 *  File:    p_Procs_Set.h
 *  Purpose: Procedures for setting p_Procs at run time
 *  Note:    this file is included by p_Procs_Dynamic/Static.cc
 *           The macros
 *              DoSetProc(what, field, length, ord)
 *              InitSetProc(field, length ord)
 *           have to be defined before this file is included
 *  Author:  obachman (Olaf Bachmann)
 *  Created: 12/00
 *  Version: $Id$
 *******************************************************************/
#include <coeffs/modulop.h>

#include <reporter/reporter.h>

// extract p_Procs properties from a ring
static inline p_Field p_FieldIs(ring r)
{
  if (rField_is_Zp(r))
    return FieldZp;
  if (rField_is_R(r)) return FieldR;
  if (rField_is_GF(r)) return FieldGF;
  if (rField_is_Q(r)) return FieldQ;
#ifdef HAVE_MORE_FIELDS_IMPLEMENTED
  if (rField_is_long_R(r)) return FieldLong_R;
  if (rField_is_long_C(r)) return FieldLong_C;
  if (rField_is_Zp_a(r)) return FieldZp_a;
  if (rField_is_Q_a(r)) return FieldQ_a;
#endif
#ifdef HAVE_RINGS
  if (rField_is_Ring(r)) return RingGeneral;
#endif
  return FieldGeneral;
}

static inline p_Length p_LengthIs(ring r)
{
  assume(r->ExpL_Size > 0);
  // here is a quick hack to take care of p_MemAddAdjust
  if (r->NegWeightL_Offset != NULL) return LengthGeneral;
  if (r->ExpL_Size == 1) return LengthOne;
  if (r->ExpL_Size == 2) return LengthTwo;
  if (r->ExpL_Size == 3) return LengthThree;
  if (r->ExpL_Size == 4) return LengthFour;
  if (r->ExpL_Size == 5) return LengthFive;
  if (r->ExpL_Size == 6) return LengthSix;
  if (r->ExpL_Size == 7) return LengthSeven;
  if (r->ExpL_Size == 8) return LengthEight;
  return LengthGeneral;
}

static inline int p_IsNomog(long* sgn, int l)
{
  int i;
  for (i=0;i<l;i++)
    if (sgn[i] > 0) return 0;

  return 1;
}

static inline int p_IsPomog(long* sgn, int l)
{
  int i;
  for (i=0;i<l;i++)
    if (sgn[i] < 0) return 0;
  return 1;
}

static inline p_Ord p_OrdIs(ring r)
{
  long* sgn = r->ordsgn;
  long l = r->ExpL_Size;
  int zero = 0;

  if (sgn[l-1] == 0)
  {
    l--;
    zero = 1;
  }

  // we always favour the pomog cases
  if (p_IsPomog(sgn,l)) return (zero ? OrdPomogZero : OrdPomog);
  if (p_IsNomog(sgn,l)) return (zero ? OrdNomogZero : OrdNomog);

  assume(l > 1);

  if (sgn[0] == -1 && p_IsPomog(&sgn[1], l-1))
    return (zero ? OrdNegPomogZero : OrdNegPomog);
  if (sgn[l-1] == -1 && p_IsPomog(sgn, l-1))
    return (zero ? OrdPomogNegZero : OrdPomogNeg);

  if (sgn[0] == 1 && p_IsNomog(&sgn[1], l-1))
    return (zero ? OrdPosNomogZero : OrdPosNomog);
  if (sgn[l-1] == 1 && p_IsNomog(sgn, l-1))
    return (zero ? OrdNomogPosZero : OrdNomogPos);

  assume(l > 2);

  if (sgn[0] == 1 && sgn[1] == 1 && p_IsNomog(&sgn[2], l-2))
    return (zero ? OrdPosPosNomogZero : OrdPosPosNomog);

  if (sgn[0] == 1 && sgn[l-1] == 1 && p_IsNomog(&sgn[1], l-2))
    return (zero ? OrdPosNomogPosZero : OrdPosNomogPos);

  if (sgn[0] == -1 && sgn[1] == 1 && p_IsNomog(&sgn[2], l-2))
    return (zero ? OrdNegPosNomogZero : OrdNegPosNomog);

  return OrdGeneral;
}

// fields of this struct are set by DoSetProc
static p_Procs_s *_p_procs;

#ifdef RDEBUG
// if set, then SetProcs sets only names, instead of functions
static int set_names = 0;
#endif

// (which##_Proc_Ptr)F ->-> cast_vptr_to_A<which##_Proc_Ptr>(F)?
#define CheckProc(which)                                    \
do                                                          \
{                                                           \
  if (p_Procs->which == NULL)                               \
  {                                                         \
    dReportBug("p_Procs is NULL");                          \
    WarnS("Singular will work properly, but much slower");  \
    WarnS("If you chose a coef ring, it may not work at all");\
    p_Procs->which =                 (which##_Proc_Ptr)(    \
      which##__FieldGeneral_LengthGeneral_OrdGeneral);       \
  }                                                         \
}                                                           \
while (0);

void nc_p_ProcsSet(ring rGR, p_Procs_s* p_Procs);

// Choose a set of p_Procs
void p_ProcsSet(ring r, p_Procs_s* p_Procs)
{
  p_Field     field = p_FieldIs(r);
  p_Length    length = p_LengthIs(r);
  p_Ord       ord = p_OrdIs(r);

  assume(p_Procs != NULL);
  memset(p_Procs, 0, sizeof(p_Procs_s));
  _p_procs = p_Procs;
  assume(IsValidSpec(field, length, ord));

  SetProcs(field, length, ord);
  extern poly p_Mult_nn_pthread(poly p, const number n, const ring r);
  #ifdef NV_OPS
  if ((field==FieldZp) && (r->cf->ch>NV_MAX_PRIME))
  {
    // set all (mult/div.) routines to FieldGeneral-variants
    SetProcs(FieldGeneral, length,ord); // p_Mult_nn, ...
    // set all non-mult/div. routines to FieldZp-variants
    SetProcs_nv(FieldZp, length,ord); // p_Delete, p_ShallowCopyDelete...
  }
  #endif
  #ifdef SI_THREADS
  else if (field==FieldQ) p_Procs->p_Mult_nn=p_Mult_nn_pthread;
  #endif
  CheckProc(p_Copy);
  CheckProc(p_Delete);
  CheckProc(p_ShallowCopyDelete);
  CheckProc(p_Mult_nn);
  CheckProc(pp_Mult_nn);
  CheckProc(pp_Mult_mm);
  CheckProc(p_Mult_mm);
  CheckProc(p_Minus_mm_Mult_qq);
  CheckProc(pp_Mult_mm_Noether);
  CheckProc(p_Add_q);
  CheckProc(p_Neg);
  CheckProc(pp_Mult_Coeff_mm_DivSelect);
  CheckProc(pp_Mult_Coeff_mm_DivSelectMult);
  CheckProc(p_Merge_q);
  CheckProc(p_kBucketSetLm);

/*
  assume(p_Procs->pp_Mult_mm_Noether != pp_Mult_mm_Noether__FieldGeneral_LengthGeneral_OrdGeneral ||
         p_Procs->p_Minus_mm_Mult_qq == p_Minus_mm_Mult_qq__FieldGeneral_LengthGeneral_OrdGeneral ||
         r->OrdSgn == 1 || r->LexOrder);
*/
#ifdef HAVE_PLURAL
#ifndef NDEBUG
  if (rIsPluralRing(r))
  {
    dReportError("Setting pProcs in p_ProcsSet (rDebugPrint!?)!!!");
    nc_p_ProcsSet(r, _p_procs); // Setup non-commutative p_Procs table!
  }
#endif
#endif
}

#ifdef RDEBUG
void p_Debug_GetSpecNames(const ring r, const char* &field, const char* &length, const char* &ord)
{
  p_Field     e_field = p_FieldIs(r);
  p_Length    e_length = p_LengthIs(r);
  p_Ord       e_ord = p_OrdIs(r);

  field  = p_FieldEnum_2_String(p_FieldIs(r));
  length = p_LengthEnum_2_String(p_LengthIs(r));
  ord    = p_OrdEnum_2_String(p_OrdIs(r));
}

void p_Debug_GetProcNames(const ring r, p_Procs_s* p_Procs)
{
  set_names = 1;
  p_ProcsSet(r, p_Procs); // changes p_Procs!!!
  set_names = 0;
}
#endif // RDEBUG