// Created on: 1993-02-02
// Created by: Christian CAILLET
// Copyright (c) 1993-1999 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_GeneralModule_HeaderFile
#define _Interface_GeneralModule_HeaderFile

#include <Standard.hxx>
#include <Standard_Type.hxx>

#include <Standard_Transient.hxx>
#include <Standard_Integer.hxx>
class Interface_InterfaceModel;
class Interface_EntityIterator;
class Interface_ShareTool;
class Interface_Check;
class Interface_CopyTool;
class TCollection_HAsciiString;

//! This class defines general services, which must be provided
//! for each type of Entity (i.e. of Transient Object processed
//! by an Interface) : Shared List, Check, Copy, Delete, Category
//!
//! To optimise processing (e.g. firstly bind an Entity to a Module
//! then calls Module), each recognized Entity Type corresponds
//! to a Case Number, determined by the Protocol each class of
//! GeneralModule belongs to.
class Interface_GeneralModule : public Standard_Transient
{

public:
  //! Specific filling of the list of Entities shared by an Entity
  //! <ent>, according a Case Number <CN> (formerly computed by
  //! CaseNum), considered in the context of a Model <model>
  //! Default calls FillSharedCase (i.e., ignores the model)
  //! Can be redefined to use the model for working
  Standard_EXPORT virtual void FillShared(const occ::handle<Interface_InterfaceModel>& model,
                                          const int                                    CN,
                                          const occ::handle<Standard_Transient>&       ent,
                                          Interface_EntityIterator&                    iter) const;

  //! Specific filling of the list of Entities shared by an Entity
  //! <ent>, according a Case Number <CN> (formerly computed by
  //! CaseNum). Can use the internal utility method Share, below
  Standard_EXPORT virtual void FillSharedCase(const int                              CN,
                                              const occ::handle<Standard_Transient>& ent,
                                              Interface_EntityIterator& iter) const = 0;

  //! Adds an Entity to a Shared List (uses GetOneItem on <iter>)
  Standard_EXPORT void Share(Interface_EntityIterator&              iter,
                             const occ::handle<Standard_Transient>& shared) const;

  //! List the Implied References of <ent> considered in the context
  //! of a Model <model> : i.e. the Entities which are Referenced
  //! while not considered as Shared (not copied if <ent> is,
  //! references not renewed by CopyCase but by ImpliedCase, only
  //! if referenced Entities have been Copied too)
  //! FillShared + ListImplied give the complete list of References
  //! Default calls ListImpliedCase (i.e. ignores the model)
  //! Can be redefined to use the model for working
  Standard_EXPORT virtual void ListImplied(const occ::handle<Interface_InterfaceModel>& model,
                                           const int                                    CN,
                                           const occ::handle<Standard_Transient>&       ent,
                                           Interface_EntityIterator&                    iter) const;

  //! List the Implied References of <ent> (see above)
  //! are Referenced while not considered as Shared (not copied if
  //! <ent> is, references not renewed by CopyCase but by
  //! ImpliedCase, only if referenced Entities have been Copied too)
  //! FillSharedCase + ListImpliedCase give the complete list of
  //! Referenced Entities
  //! The provided default method does nothing (Implied References
  //! are specific of a little amount of Entity Classes).
  Standard_EXPORT virtual void ListImpliedCase(const int                              CN,
                                               const occ::handle<Standard_Transient>& ent,
                                               Interface_EntityIterator&              iter) const;

  //! Specific Checking of an Entity <ent>
  //! Can check context queried through a ShareTool, as required
  Standard_EXPORT virtual void CheckCase(const int                              CN,
                                         const occ::handle<Standard_Transient>& ent,
                                         const Interface_ShareTool&             shares,
                                         occ::handle<Interface_Check>&          ach) const = 0;

  //! Specific answer to the question "is Copy properly implemented"
  //! Remark that it should be in phase with the implementation of
  //! NewVoid+CopyCase/NewCopyCase
  //! Default returns always False, can be redefined
  Standard_EXPORT virtual bool CanCopy(const int                              CN,
                                       const occ::handle<Standard_Transient>& ent) const;

  //! Dispatches an entity
  //! Returns True if it works by copy, False if it just duplicates
  //! the starting Handle
  //!
  //! Dispatching means producing a new entity, image of the
  //! starting one, in order to be put into a new Model, this Model
  //! being itself the result of a dispatch from an original Model
  //!
  //! According to the cases, dispatch can either
  //! * just return <entto> as equating <entfrom>
  //! -> the new model designates the starting entity : it is
  //! lighter, but the dispatched entity being shared might not be
  //! modified for dispatch
  //! * copy <entfrom> to <entto>
  //! by calling NewVoid+CopyCase (two steps) or NewCopiedCase (1)
  //! -> the dispatched entity is a COPY, hence it can be modified
  //!
  //! The provided default just duplicates the handle without
  //! copying, then returns False. Can be redefined
  Standard_EXPORT virtual bool Dispatch(const int                              CN,
                                        const occ::handle<Standard_Transient>& entfrom,
                                        occ::handle<Standard_Transient>&       entto,
                                        Interface_CopyTool&                    TC) const;

  //! Creates a new void entity <entto> according to a Case Number
  //! This entity remains to be filled, by reading from a file or
  //! by copying from another entity of same type (see CopyCase)
  Standard_EXPORT virtual bool NewVoid(const int                        CN,
                                       occ::handle<Standard_Transient>& entto) const = 0;

  //! Specific Copy ("Deep") from <entfrom> to <entto> (same type)
  //! by using a CopyTool which provides its working Map.
  //! Use method Transferred from CopyTool to work
  Standard_EXPORT virtual void CopyCase(const int                              CN,
                                        const occ::handle<Standard_Transient>& entfrom,
                                        const occ::handle<Standard_Transient>& entto,
                                        Interface_CopyTool&                    TC) const = 0;

  //! Specific operator (create+copy) defaulted to do nothing.
  //! It can be redefined : When it is not possible to work in two
  //! steps (NewVoid then CopyCase). This can occur when there is
  //! no default constructor : hence the result <entto> must be
  //! created with an effective definition.
  //! Remark : if NewCopiedCase is defined, CopyCase has nothing to do
  //! Returns True if it has produced something, false else
  Standard_EXPORT virtual bool NewCopiedCase(const int                              CN,
                                             const occ::handle<Standard_Transient>& entfrom,
                                             occ::handle<Standard_Transient>&       entto,
                                             Interface_CopyTool&                    TC) const;

  //! Specific Copying of Implied References
  //! A Default is provided which does nothing (must current case !)
  //! Already copied references (by CopyFrom) must remain unchanged
  //! Use method Search from CopyTool to work
  Standard_EXPORT virtual void RenewImpliedCase(const int                              CN,
                                                const occ::handle<Standard_Transient>& entfrom,
                                                const occ::handle<Standard_Transient>& entto,
                                                const Interface_CopyTool&              TC) const;

  //! Prepares an entity to be deleted. What does it mean :
  //! Basically, any class of entity may define its own destructor
  //! By default, it does nothing but calling destructors on fields
  //! With the Memory Manager, it is useless to call destructor,
  //! it is done automatically when the Handle is nullified(cleared)
  //! BUT this is ineffective in looping structures (whatever these
  //! are "Implied" references or not).
  //!
  //! THUS : if no loop may appear in definitions, a class which
  //! inherits from TShared is correctly managed by automatic way
  //! BUT if there can be loops (or simply back pointers), they must
  //! be broken, for instance by clearing fields of one of the nodes
  //! The default does nothing, to be redefined if a loop can occur
  //! (Implied generally requires WhenDelete, but other cases can
  //! occur)
  //!
  //! Warning : <dispatched> tells if the entity to be deleted has been
  //! produced by Dispatch or not. Hence WhenDelete must be in
  //! coherence with Dispatch
  //! Dispatch can either copy or not.
  //! If it copies the entity, this one should be deleted
  //! If it doesn't (i.e. duplicates the handle) nothing to do
  //!
  //! If <dispatch> is False, normal deletion is to be performed
  Standard_EXPORT virtual void WhenDeleteCase(const int                              CN,
                                              const occ::handle<Standard_Transient>& ent,
                                              const bool dispatched) const;

  //! Returns a category number which characterizes an entity
  //! Category Numbers are managed by the class Category
  //! <shares> can be used to evaluate this number in the context
  //! Default returns 0 which means "unspecified"
  Standard_EXPORT virtual int CategoryNumber(const int                              CN,
                                             const occ::handle<Standard_Transient>& ent,
                                             const Interface_ShareTool&             shares) const;

  //! Determines if an entity brings a Name (or widerly, if a Name
  //! can be attached to it, through the ShareTool
  //! By default, returns a Null Handle (no name can be produced)
  //! Can be redefined
  //!
  //! Warning : While this string may be edited on the spot, if it is a read
  //! field, the returned value must be copied before.
  Standard_EXPORT virtual occ::handle<TCollection_HAsciiString> Name(
    const int                              CN,
    const occ::handle<Standard_Transient>& ent,
    const Interface_ShareTool&             shares) const;

  DEFINE_STANDARD_RTTIEXT(Interface_GeneralModule, Standard_Transient)
};

#endif // _Interface_GeneralModule_HeaderFile
