OCCT

// Created on: 1991-04-16
// Created by: Arnaud BOUZY
// Copyright (c) 1991-1999 Matra Datavision
// Copyright (c) 1999-2014 OPEN CASCADE SAS
//
// This file is part of Open CASCADE Technology software library.
//
// This library is free software; you can redistribute it and/or modify it under
// the terms of the GNU Lesser General Public License version 2.1 as published
// by the Free Software Foundation, with special exception defined in the file
// OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
// distribution for complete text of the license and disclaimer of any warranty.
//
// Alternatively, this file may be used under the terms of Open CASCADE
// commercial license or contractual agreement.

#include <Expr_InvalidOperand.hxx>
#include <Expr_NamedUnknown.hxx>
#include <Expr_PolyExpression.hxx>
#include <Standard_DimensionMismatch.hxx>
#include <Standard_Type.hxx>

IMPLEMENT_STANDARD_RTTIEXT(Expr_PolyExpression, Expr_GeneralExpression)

Expr_PolyExpression::Expr_PolyExpression() = default;

int Expr_PolyExpression::NbOperands() const
{
  return myOperands.Length();
}

void Expr_PolyExpression::SetOperand(const occ::handle<Expr_GeneralExpression>& exp,
                                     const int                                  index)
{
  occ::handle<Expr_PolyExpression> me = this;
  if (exp == me)
  {
    throw Expr_InvalidOperand();
  }
  if (exp->Contains(me))
  {
    throw Expr_InvalidOperand();
  }
  myOperands(index) = exp;
}

void Expr_PolyExpression::AddOperand(const occ::handle<Expr_GeneralExpression>& exp)
{
  myOperands.Append(exp);
}

void Expr_PolyExpression::RemoveOperand(const int index)
{
  if (myOperands.Length() <= 2)
  {
    throw Standard_DimensionMismatch();
  }
  myOperands.Remove(index);
}

int Expr_PolyExpression::NbSubExpressions() const
{
  return NbOperands();
}

const occ::handle<Expr_GeneralExpression>& Expr_PolyExpression::SubExpression(const int I) const
{
  return Operand(I);
}

bool Expr_PolyExpression::ContainsUnknowns() const
{
  bool                                found = false;
  int                                 nbop  = NbOperands();
  int                                 i     = 1;
  occ::handle<Expr_GeneralExpression> expop;

  while ((!found) && (i <= nbop))
  {
    expop = Operand(i);
    found = expop->IsKind(STANDARD_TYPE(Expr_NamedUnknown));
    i++;
  }
  i = 1;
  while ((!found) && (i <= nbop))
  {
    expop = Operand(i);
    found = expop->ContainsUnknowns();
    i++;
  }
  return found;
}

bool Expr_PolyExpression::Contains(const occ::handle<Expr_GeneralExpression>& exp) const
{
  bool                                found = false;
  int                                 nbop  = NbOperands();
  int                                 i     = 1;
  occ::handle<Expr_GeneralExpression> expop;

  while ((!found) && (i <= nbop))
  {
    expop = Operand(i);
    found = (expop == exp);
    i++;
  }
  i = 1;
  while ((!found) && (i <= nbop))
  {
    expop = Operand(i);
    found = expop->Contains(exp);
    i++;
  }
  return found;
}

void Expr_PolyExpression::Replace(const occ::handle<Expr_NamedUnknown>&      var,
                                  const occ::handle<Expr_GeneralExpression>& with)
{
  int                                 nbop = NbOperands();
  int                                 i;
  occ::handle<Expr_GeneralExpression> expop;

  for (i = 1; i <= nbop; i++)
  {
    expop = Operand(i);
    if (expop == var)
    {
      SetOperand(with, i);
    }
    else
    {
      if (expop->Contains(var))
      {
        expop->Replace(var, with);
      }
    }
  }
}

occ::handle<Expr_GeneralExpression> Expr_PolyExpression::Simplified() const
{
  occ::handle<Expr_PolyExpression>    cop = occ::down_cast<Expr_PolyExpression>(Copy());
  int                                 i;
  int                                 max = cop->NbOperands();
  occ::handle<Expr_GeneralExpression> op;
  for (i = 1; i <= max; i++)
  {
    op = cop->Operand(i);
    cop->SetOperand(op->Simplified(), i);
  }
  return cop->ShallowSimplified();
}