#pragma once

#ifndef SHADINGCONTEXT_H

#define SHADINGCONTEXT_H

#include <memory></memory>

// Glew include

#include <gl glew.h=""></gl>

// TnzCore includes

#include "traster.h"

// Qt includes

#include <qdatetime></qdatetime>

#include <qopenglframebufferobjectformat></qopenglframebufferobjectformat>

#include <qopenglwidget></qopenglwidget>

#undef DVAPI

#undef DVVAR

#ifdef TNZSTDFX_EXPORTS

#define DVAPI DV_EXPORT_API

#define DVVAR DV_EXPORT_VAR

#else

#define DVAPI DV_IMPORT_API

#define DVVAR DV_IMPORT_VAR

#endif

//=========================================================

//    Forward declarations

class QObject;

class QOpenGLShaderProgram;

class QDateTime;

class QOffscreenSurface;

//=========================================================

class DVAPI ShadingContext {

public:

  enum Support { OK, NO_PIXEL_BUFFER, NO_SHADERS };

public:

  ShadingContext(QOffscreenSurface *);

  ~ShadingContext();

  //! Returns the status of OpenGL shading support.

  static Support support();

  bool isValid() const;

  void makeCurrent();

  void doneCurrent();

  /*!

Resizes the output buffer to the specified size. Requires that

the context is made current before invocation. In case lx or ly are 0,

the context's output buffer is destroyed.

*/

  void resize(int lx, int ly, const QOpenGLFramebufferObjectFormat &fmt =

                                  QOpenGLFramebufferObjectFormat());

  QOpenGLFramebufferObjectFormat format() const;

  TDimension size() const;

  //! Surrenders ownership of the supplied shader program to the shading

  //! context.

  void addShaderProgram(const QString &shaderName,

                        QOpenGLShaderProgram *program);

  void addShaderProgram(const QString &shaderName,

                        QOpenGLShaderProgram *program,

                        const QDateTime &lastModified);

  bool removeShaderProgram(const QString &shaderName);

  QOpenGLShaderProgram *shaderProgram(const QString &shaderName) const;

  QDateTime lastModified(const QString &shaderName) const;

  std::pair<qopenglshaderprogram *,="" qdatetime=""> shaderData(</qopenglshaderprogram>

      const QString &shaderName) const;

  GLuint loadTexture(const TRasterP &src, GLuint texUnit);  //!< Loads a texture

                                                            //! and binds it to

  //! the specified

  //! texture unit.

  //!  \return  The OpenGL texture id of the loaded texture.      \param src

  //!  Loaded texture.  \param texUnit  Unit the texture will be bound to.

  void unloadTexture(GLuint texId);  //!< Releases the specified texture id.

  //! Renders the active shader program to the specified raster.

  void draw(const TRasterP &dst);

  //! Performs transform feedback with the specified varying variables

  void transformFeedback(int varyingsCount, const GLsizeiptr *varyingSizes,

                         GLvoid **bufs);

private:

  struct Imp;

  std::unique_ptr<imp> m_imp;</imp>

  // Not copyable

  ShadingContext(const ShadingContext &);

  ShadingContext &operator=(const ShadingContext &);

};

class TQOpenGLWidget : public QOpenGLWidget {

public:

  TQOpenGLWidget();

  void initializeGL() override;

};

#endif  // SHADINGCONTEXT_H