// Created on: 1992-11-02
// Created by: Christian CAILLET
// Copyright (c) 1992-1999 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 _Interface_EntityList_HeaderFile
#define _Interface_EntityList_HeaderFile

#include <Standard.hxx>
#include <Standard_DefineAlloc.hxx>
#include <Standard_Handle.hxx>

#include <Standard_Integer.hxx>
#include <Standard_Boolean.hxx>
#include <Standard_Type.hxx>
class Standard_Transient;
class Standard_OutOfRange;
class Interface_InterfaceError;
class Standard_NullObject;
class Interface_EntityIterator;


//! This class defines a list of Entities (Transient Objects),
//! it can be used as a field of other Transient classes, with
//! these features :
//! - oriented to define a little list, that is, slower than an
//! Array or a Map of Entities for a big count (about 100 and
//! over), but faster than a Sequence
//! - allows to work as a Sequence, limited to Clear, Append,
//! Remove, Access to an Item identified by its rank in the list
//! - space saving, compared to a Sequence, especially for little
//! amounts; better than an Array for a very little amount (less
//! than 10) but less good for a greater amount
//!
//! Works in conjunction with EntityCluster
//! An EntityList gives access to a list of Entity Clusters, which
//! are chained (in one sense : Single List)
//! Remark : a new Item may not be Null, because this is the
//! criterium used for "End of List"
class Interface_EntityList 
{
public:

  DEFINE_STANDARD_ALLOC

  
  //! Creates a List as beeing empty
  Standard_EXPORT Interface_EntityList();
  
  //! Clears the List
  Standard_EXPORT void Clear();
  
  //! Appends an Entity, that is to the END of the list
  //! (keeps order, but works slowerly than Add, see below)
  Standard_EXPORT void Append (const Handle(Standard_Transient)& ent);
  
  //! Adds an Entity to the list, that is, with NO REGARD about the
  //! order (faster than Append if count becomes greater than 10)
  Standard_EXPORT void Add (const Handle(Standard_Transient)& ent);
  
  //! Removes an Entity from the list, if it is there
  Standard_EXPORT void Remove (const Handle(Standard_Transient)& ent);
  
  //! Removes an Entity from the list, given its rank
  Standard_EXPORT void Remove (const Standard_Integer num);
  
  //! Returns True if the list is empty
  Standard_EXPORT Standard_Boolean IsEmpty() const;
  
  //! Returns count of recorded Entities
  Standard_EXPORT Standard_Integer NbEntities() const;
  
  //! Returns an Item given its number. Beware about the way the
  //! list was filled (see above, Add and Append)
  Standard_EXPORT const Handle(Standard_Transient)& Value (const Standard_Integer num) const;
  
  //! Returns an Item given its number. Beware about the way the
  //! list was filled (see above, Add and Append)
  Standard_EXPORT void SetValue (const Standard_Integer num, const Handle(Standard_Transient)& ent);
  
  //! fills an Iterator with the content of the list
  //! (normal way to consult a list which has been filled with Add)
  Standard_EXPORT void FillIterator (Interface_EntityIterator& iter) const;
  
  //! Returns count of Entities of a given Type (0 : none)
  Standard_EXPORT Standard_Integer NbTypedEntities (const Handle(Standard_Type)& atype) const;
  
  //! Returns the Entity which is of a given type.
  //! If num = 0 (D), there must be ONE AND ONLY ONE
  //! If num > 0, returns the num-th entity of this type
  Standard_EXPORT Handle(Standard_Transient) TypedEntity (const Handle(Standard_Type)& atype, const Standard_Integer num = 0) const;




protected:





private:



  Handle(Standard_Transient) theval;


};







#endif // _Interface_EntityList_HeaderFile