#pragma once

#ifndef TMETAIMAGE_INCLUDED

#define TMETAIMAGE_INCLUDED

#include "timage.h"

#include "tthreadmessage.h"

#include "tsmartpointer.h"

#include "tvariant.h"

#include "tconstwrapper.h"

#include <QString>

#include <QReadLocker>

#include <QWriteLocker>

#include <QReadWriteLock>

#include <string>

#undef DVAPI

#undef DVVAR

#ifdef TMETAIMAGE_EXPORTS

#define DVAPI DV_EXPORT_API

#define DVVAR DV_EXPORT_VAR

#else

#define DVAPI DV_IMPORT_API

#define DVVAR DV_IMPORT_VAR

#endif

//-------------------------------------------------------------------

class TMetaObject;

class TMetaObjectHandler;

typedef TSmartPointerT<TMetaObject> TMetaObjectP;  //!< smart pointer to TMetaObject

typedef TMetaObjectP::Holder        TMetaObjectH;  //!< smart holder of TMetaObject

typedef TMetaObjectP::Const         TMetaObjectPC; //!< smart pointer to constant TMetaObject

typedef std::vector<TMetaObjectP> TMetaObjectList;

typedef TConstArrayWrapperT<TMetaObjectPC, TMetaObjectP> TMetaObjectListCW; // TMetaObjectListConstWrapper

//-------------------------------------------------------------------

class DVAPI TMetaObjectType {

public:

  const TStringId name;

  TMetaObjectType(const TStringId &name);

  virtual ~TMetaObjectType();

  void registerAlias(const TStringId &alias);

  void unregisterAlias(const TStringId &alias);

  virtual TMetaObjectHandler* createHandler(TMetaObject &obj) const

    { return 0; }

  virtual QString getLocalName() const

    { return QString::fromStdString(name.str()); }

};

//-------------------------------------------------------------------

class DVAPI TMetaObject: public TSmartObject, public TVariantOwner {

public:

  typedef TMetaObjectHandler* (*Fabric)(TMetaObject&);

  typedef std::map<TStringId, const TMetaObjectType*> Registry;

  struct LinkedList {

    TMetaObject *first, *last;

    LinkedList(): first(), last() { }

  };

  typedef std::map<TStringId, LinkedList> LinkedMap;

  typedef LinkedMap::iterator LinkedMapEntry;

private:

  LinkedMapEntry m_typeLink;

  TMetaObject *m_previous, *m_next;

  const TMetaObjectType *m_typeDesc;

  TMetaObjectHandler *m_handler;

  TVariant m_data;

  static Registry& registry();

  static LinkedMap& linkedMap();

  static void rewrapAll(const TStringId &type);

  void rewrap(const TStringId &type);

  void linkToType(const TStringId &type);

  void unlinkFromType();

  TMetaObject(const TMetaObject &other);

public:

  explicit TMetaObject(const TStringId &typeName = TStringId(), const TVariant &data = TVariant());

  explicit TMetaObject(const std::string &typeName, const TVariant &data = TVariant());

  ~TMetaObject();

  void setType(const TStringId &name);

  inline void setType(const std::string &name)

    { setType(TStringId(name)); }

  inline void resetType()

    { setType(TStringId()); }

  inline const TMetaObjectType* getTypeDesc() const

    { return m_typeDesc; }

  inline const TStringId& getType() const

    { return m_typeLink->first; }

  inline const std::string& getTypeName() const

    { return getType().str(); }

  inline const TVariant& data() const

    { return m_data; }

  inline TVariant& data()

    { return m_data; }

  void setDefaults();

  template<typename T>

  const T* getHandler() const

    { return dynamic_cast<const T*>(m_handler); }

  template<typename T>

  T* getHandler()

    { return dynamic_cast<T*>(m_handler); }

  TMetaObjectHandler* handler() { return m_handler; }

  const TMetaObjectHandler* handler() const { return m_handler; }

  void onVariantChanged(const TVariant &value) override;

  virtual TMetaObject* clone() const;

public:

  static const Registry& getRegistry() { return registry(); }

  static void registerType(const TStringId &name, const TMetaObjectType &type); //!< register new or add alias

  static void unregisterType(const TStringId &name); //!< unregister single alias

  static void unregisterType(const TMetaObjectType &type); //!< unregister all aliases

  static const TMetaObjectType* findType(const TStringId &name);

};

//-------------------------------------------------------------------

class DVAPI TMetaObjectHandler {

protected:

  class LockEvents {

  public:

    TMetaObjectHandler &owner;

    explicit LockEvents(TMetaObjectHandler &owner):

      owner(owner) { ++owner.m_locks; }

    ~LockEvents() { --owner.m_locks; }

  };

private:

  TMetaObject &m_object;

  const TMetaObjectType &m_typeDesc;

  TAtomicVar m_locks;

public:

  TMetaObjectHandler(TMetaObject &object):

    m_object(object),

    m_typeDesc(*m_object.getTypeDesc())

      { assert(m_object.getTypeDesc()); }

  virtual ~TMetaObjectHandler() { }

  inline const TMetaObjectType& getTypeDesc() const

    { return m_typeDesc; }

  inline const TStringId& getType() const

    { return getTypeDesc().name; }

  inline const std::string& getTypeName() const

    { return getType().str(); }

  inline const TMetaObject& object() const

    { return m_object; }

  inline TMetaObject& object()

    { return m_object; }

  inline const TStringId& getAlias() const

    { return object().getType(); }

  inline const std::string& getAliasName() const

    { return getAlias().str(); }

  inline const TVariant& data() const

    { return object().data(); }

  inline TVariant& data()

    { return object().data(); }

protected:

  virtual void onSetDefaults() { }

  virtual void onDataChanged(const TVariant &value) { }

  virtual void onFixData() { }

public:

  void setDefaults()

    { onSetDefaults(); }

  void dataChanged(const TVariant &value)

    { if (m_locks == 0) onDataChanged(value); }

  void fixData()

    { LockEvents lock(*this); onFixData(); }

};

//-------------------------------------------------------------------

//! An image containing an assistants for painting.

class DVAPI TMetaImage final : public TImage {

public:

  class Reader: public QReadLocker {

  private:

    const TMetaImage &m_image;

    const TMetaObjectListCW m_objects;

  public:

    Reader(const TMetaImage &image):

      QReadLocker(&image.m_rwLock),

      m_image(image),

      m_objects(image.m_objects) { }

    const TMetaImage& image() const

      { return m_image; }

    const TMetaObjectListCW& get() const

      { return m_objects; }

    const TMetaObjectListCW& operator*() const

      { return get(); }

    const TMetaObjectListCW* operator->() const

      { return &get(); }

  };

  class Writer: public QWriteLocker {

  private:

    TMetaImage &m_image;

  public:

    Writer(TMetaImage &image):

      QWriteLocker(&image.m_rwLock), m_image(image) { }

    TMetaImage& image() const

      { return m_image; }

    TMetaObjectList& get() const

      { return m_image.m_objects; }

    TMetaObjectList& operator*() const

      { return get(); }

    TMetaObjectList* operator->() const

      { return &get(); }

  };

private:

  mutable QReadWriteLock m_rwLock;

  TMetaObjectList m_objects;

  TMetaImage(const TMetaImage &other);

  //! not implemented

  TMetaImage &operator=(const TMetaImage &) { return *this; }

public:

  TMetaImage();

  ~TMetaImage();

  //! Return the image type

  TImage::Type getType() const override { return TImage::META; }

  //! Return a clone of image

  TImage* cloneImage() const override;

  //! Return the bbox of the image

  TRectD getBBox() const override;

};

#endif