// Created on: 2013-07-15
// Created by: Anton POLETAEV
// Copyright (c) 2013-2014 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 _Graphic3d_SequenceOfHClipPlane_HeaderFile
#define _Graphic3d_SequenceOfHClipPlane_HeaderFile

#include <NCollection_Sequence.hxx>
#include <Graphic3d_ClipPlane.hxx>

//! Class defines a Clipping Volume as a logical OR (disjunction) operation between Graphic3d_ClipPlane in sequence.
//! Each Graphic3d_ClipPlane represents either a single Plane clipping a halfspace (direction is specified by normal),
//! or a sub-chain of planes defining a logical AND (conjunction) operation.
//! Therefore, this collection allows defining a Clipping Volume through the limited set of Boolean operations between clipping Planes.
//!
//! The Clipping Volume can be assigned either to entire View or to a specific Object;
//! in the latter case property ToOverrideGlobal() will specify if Object planes should override (suppress) globally defined ones
//! or extend their definition through logical OR (disjunction) operation.
//!
//! Note that defining (many) planes will lead to performance degradation, and Graphics Driver may limit
//! the overall number of simultaneously active clipping planes - but at least 6 planes should be supported on all configurations.
class Graphic3d_SequenceOfHClipPlane : public Standard_Transient
{
  DEFINE_STANDARD_RTTIEXT(Graphic3d_SequenceOfHClipPlane, Standard_Transient)
public:

  //! Iterator through clipping planes.
  class Iterator : public NCollection_Sequence<Handle(Graphic3d_ClipPlane)>::Iterator
  {
  public:
    Iterator() {}
    Iterator (const Graphic3d_SequenceOfHClipPlane& thePlanes) : NCollection_Sequence<Handle(Graphic3d_ClipPlane)>::Iterator (thePlanes.myItems) {}
    Iterator (const Handle(Graphic3d_SequenceOfHClipPlane)& thePlanes) { Init (thePlanes); }

    void Init (const Graphic3d_SequenceOfHClipPlane& thePlanes) { NCollection_Sequence<Handle(Graphic3d_ClipPlane)>::Iterator::Init (thePlanes.myItems); }
    void Init (const Handle(Graphic3d_SequenceOfHClipPlane)& thePlanes)
    {
      if (!thePlanes.IsNull())
      {
        NCollection_Sequence<Handle(Graphic3d_ClipPlane)>::Iterator::Init (thePlanes->myItems);
      }
      else
      {
        *this = Iterator();
      }
    }
  };

public:

  //! Empty constructor.
  Standard_EXPORT Graphic3d_SequenceOfHClipPlane();

  //! Return true if local properties should override global properties.
  Standard_Boolean ToOverrideGlobal() const { return myToOverrideGlobal; }

  //! Setup flag defining if local properties should override global properties.
  void SetOverrideGlobal (const Standard_Boolean theToOverride) { myToOverrideGlobal = theToOverride; }

  //! Return TRUE if sequence is empty.
  bool IsEmpty() const { return myItems.IsEmpty(); }

  //! Return the number of items in sequence.
  Standard_Integer Size() const { return myItems.Size(); }

  //! Append a plane.
  //! @return TRUE if new item has been added (FALSE if item already existed)
  Standard_EXPORT bool Append (const Handle(Graphic3d_ClipPlane)& theItem);

  //! Remove a plane.
  //! @return TRUE if item has been found and removed
  Standard_EXPORT bool Remove (const Handle(Graphic3d_ClipPlane)& theItem);

  //! Remove a plane.
  void Remove (Iterator& theItem) { myItems.Remove (theItem); }

  //! Clear the items out.
  void Clear()
  {
    myItems.Clear();
  }

  //! Return the first item in sequence.
  const Handle(Graphic3d_ClipPlane)& First() const { return myItems.First(); }

protected:

  NCollection_Sequence<Handle(Graphic3d_ClipPlane)> myItems;
  Standard_Boolean myToOverrideGlobal;

};

DEFINE_STANDARD_HANDLE(Graphic3d_SequenceOfHClipPlane, Standard_Transient)

#endif // _Graphic3d_SequenceOfHClipPlane_HeaderFile