// Created on: 1997-12-10
// Created by: Denis PASCAL
// Copyright (c) 1997-1999 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.

#ifndef _TDataStd_Variable_HeaderFile
#define _TDataStd_Variable_HeaderFile

#include "Standard.hxx"

#include "TCollection_AsciiString.hxx"
#include "TDF_Attribute.hxx"
#include "Standard_Real.hxx"
#include "TDataStd_RealEnum.hxx"
#include "Standard_OStream.hxx"
class Standard_GUID;
class TDF_Label;
class TCollection_ExtendedString;
class TDataStd_Real;
class TDataStd_Expression;
class TDF_RelocationTable;
class TDF_DataSet;

//! Variable attribute.
//! ==================
//!
//! * A variable is associated to a TDataStd_Real (which
//! contains its current value) and a TDataStd_Name
//! attribute (which contains its name). It contains a
//! constant flag, and a Unit
//!
//! * An expression may be assigned to a variable. In
//! thatcase the expression is handled by the associated
//! Expression Attribute and the Variable returns True to
//! the method <IsAssigned>.
class TDataStd_Variable : public TDF_Attribute
{

public:
  //! class methods
  //! =============
  Standard_EXPORT static const Standard_GUID& GetID();

  //! Find, or create, a Variable attribute.
  //! Real methods
  //! ============
  Standard_EXPORT static occ::handle<TDataStd_Variable> Set(const TDF_Label& label);

  Standard_EXPORT TDataStd_Variable();

  //! set or change the name of the variable, in myUnknown
  //! and my associated Name attribute.
  Standard_EXPORT void Name(const TCollection_ExtendedString& string);

  //! returns string stored in the associated Name
  //! attribute.
  Standard_EXPORT const TCollection_ExtendedString& Name() const;

  //! retrieve or create the associated real attribute and
  //! set the value <value>.
  Standard_EXPORT void Set(const double value) const;

  //! Obsolete method that will be removed in next versions.
  //! The dimension argument is not supported in the persistence mechanism.
  Standard_DEPRECATED("TDataStd_Variable::Set(value, dimension) is deprecated. Please use "
                      "TDataStd_Variable::Set(value) instead.")
  Standard_EXPORT void Set(const double value, const TDataStd_RealEnum dimension) const;

  //! returns True if a Real attribute is associated.
  Standard_EXPORT bool IsValued() const;

  //! returns value stored in associated Real attribute.
  Standard_EXPORT double Get() const;

  //! returns associated Real attribute.
  Standard_EXPORT occ::handle<TDataStd_Real> Real() const;

  //! returns True if an Expression attribute is associated.
  //! create(if doesn't exist), set and returns the assigned
  //! expression attribute.
  Standard_EXPORT bool IsAssigned() const;

  //! create(if doesn't exist) and returns the assigned
  //! expression attribute. fill it after.
  Standard_EXPORT occ::handle<TDataStd_Expression> Assign() const;

  //! if <me> is assigned delete the associated expression
  //! attribute.
  Standard_EXPORT void Desassign() const;

  //! if <me> is assigned, returns associated Expression
  //! attribute.
  Standard_EXPORT occ::handle<TDataStd_Expression> Expression() const;

  //! shortcut for <Real()->IsCaptured()>
  Standard_EXPORT bool IsCaptured() const;

  //! A constant value is not modified by regeneration.
  Standard_EXPORT bool IsConstant() const;

  Standard_EXPORT void Unit(const TCollection_AsciiString& unit);

  //! to read/write fields
  //! ====================
  Standard_EXPORT const TCollection_AsciiString& Unit() const;

  //! if <status> is True, this variable will not be
  //! modified by the solver.
  Standard_EXPORT void Constant(const bool status);

  Standard_EXPORT const Standard_GUID& ID() const override;

  Standard_EXPORT void Restore(const occ::handle<TDF_Attribute>& With) override;

  Standard_EXPORT occ::handle<TDF_Attribute> NewEmpty() const override;

  Standard_EXPORT void Paste(const occ::handle<TDF_Attribute>&       Into,
                             const occ::handle<TDF_RelocationTable>& RT) const override;

  //! to export reference to the associated Name attribute.
  Standard_EXPORT void References(const occ::handle<TDF_DataSet>& DS) const override;

  Standard_EXPORT Standard_OStream& Dump(Standard_OStream& anOS) const override;

  //! Dumps the content of me into the stream
  Standard_EXPORT void DumpJson(Standard_OStream& theOStream, int theDepth = -1) const override;

  DEFINE_STANDARD_RTTIEXT(TDataStd_Variable, TDF_Attribute)

private:
  bool                    isConstant;
  TCollection_AsciiString myUnit;
};

#endif // _TDataStd_Variable_HeaderFile