// Copyright (c) 2021 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 _BinTools_IStream_HeaderFile
#define _BinTools_IStream_HeaderFile

#include <BinTools.hxx>
#include <BinTools_ObjectType.hxx>
#include <TopAbs_ShapeEnum.hxx>
#include <TopAbs_Orientation.hxx>
#include <gp_Pnt.hxx>

//! Substitution of IStream for shape reader for fast management of position in the file (get and go)
//! and operation on all reading types.
class BinTools_IStream
{
public:

  //! Creates IStream using the current stream IStream.
  Standard_EXPORT BinTools_IStream (Standard_IStream& theStream);

  //! Reads and returns the type.
  Standard_EXPORT BinTools_ObjectType ReadType();
  //! Returns the last read type.
  Standard_EXPORT const BinTools_ObjectType& LastType() { return myLastType; }
  //! Returns the shape type by the last retrieved type.
  Standard_EXPORT TopAbs_ShapeEnum ShapeType();
  //! Returns the shape orientation by the last retrieved type.
  Standard_EXPORT TopAbs_Orientation ShapeOrientation();

  //! Returns the current position in the stream.
  Standard_EXPORT uint64_t Position() { return myPosition; }
  //! Moves the current stream position to the given one.
  Standard_EXPORT void GoTo (const uint64_t& thePosition);

  //! Returns true if the last restored type is one of a reference
  Standard_EXPORT Standard_Boolean IsReference();
  //! Reads a reference IStream using the last restored type.
  Standard_EXPORT uint64_t ReadReference();
  //! Returns the original IStream.
  Standard_EXPORT Standard_IStream& Stream() { return *myStream; }
  //! Makes up to date the myPosition because myStream was used outside and position is changed.
  Standard_EXPORT void UpdatePosition() { myPosition = uint64_t (myStream->tellg()); }

  //! Returns false if stream reading is failed.
  Standard_EXPORT operator bool() const;
  //! Reads real value from the stream.
  Standard_EXPORT Standard_Real ReadReal() { Standard_Real aValue; *this >> aValue; return aValue; }
  Standard_EXPORT BinTools_IStream& operator >> (Standard_Real& theValue);
  //! Reads integer value from the stream.
  Standard_EXPORT Standard_Integer ReadInteger() { Standard_Integer aValue; *this >> aValue; return aValue; }
  Standard_EXPORT BinTools_IStream& operator >> (Standard_Integer& theValue);
  //! Reads point coordinates value from the stream.
  Standard_EXPORT gp_Pnt ReadPnt() { gp_Pnt aValue; *this >> aValue; return aValue; }
  Standard_EXPORT BinTools_IStream& operator >> (gp_Pnt& theValue);
  //! Reads byte value from the stream.
  Standard_EXPORT Standard_Byte ReadByte() { Standard_Byte aValue; *this >> aValue; return aValue; }
  Standard_EXPORT BinTools_IStream& operator >> (Standard_Byte& theValue);
  //! Reads boolean value from the stream (stored as one byte).
  Standard_EXPORT Standard_Boolean ReadBool() { return ReadByte() != 0; }
  Standard_EXPORT BinTools_IStream& operator >> (Standard_Boolean& theValue) { theValue = ReadByte() != 0; return *this; }
  //! Reads short real value from the stream.
  Standard_EXPORT Standard_ShortReal ReadShortReal() { Standard_ShortReal aValue; *this >> aValue; return aValue; }
  Standard_EXPORT BinTools_IStream& operator >> (Standard_ShortReal& theValue);
  //! Reads transformation value from the stream.
  Standard_EXPORT BinTools_IStream& operator >> (gp_Trsf& theValue);
  //! Reads 3 boolean values from one byte
  Standard_EXPORT void ReadBools (Standard_Boolean& theBool1, Standard_Boolean& theBool2, Standard_Boolean& theBool3);
  //! Reads 7 boolean values from one byte
  Standard_EXPORT void ReadBools (Standard_Boolean& theBool1, Standard_Boolean& theBool2, Standard_Boolean& theBool3,
    Standard_Boolean& theBool4, Standard_Boolean& theBool5, Standard_Boolean& theBool6, Standard_Boolean& theBool7);


private:
  Standard_IStream* myStream; ///< pointer to the stream
  uint64_t myPosition; ///< equivalent to tellg returned value for fast access
  BinTools_ObjectType myLastType; ///< last type that was read
};

#endif // _BinTools_IStream_HeaderFile