// Created on: 2011-10-20
// Created by: Sergey ZERCHANINOV
// Copyright (c) 2011-2014 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 _OpenGl_GraphicDriver_HeaderFile
#define _OpenGl_GraphicDriver_HeaderFile

#include "Graphic3d_GraphicDriver.hxx"

#include "Aspect_DisplayConnection.hxx"
#include "Graphic3d_CView.hxx"
#include "Graphic3d_CStructure.hxx"
#include "NCollection_DataMap.hxx"
#include "OpenGl_Context.hxx"

class Aspect_Window;
class OpenGl_Structure;
class OpenGl_View;
class OpenGl_Window;

//! Tool class to implement consistent state counter
//! for objects inside the same driver instance.
class OpenGl_StateCounter
{
public:
  OpenGl_StateCounter()
      : myCounter(0)
  {
  }

  size_t Increment() { return ++myCounter; }

private:
  size_t myCounter;
};

//! This class defines an OpenGl graphic driver
class OpenGl_GraphicDriver : public Graphic3d_GraphicDriver
{
  DEFINE_STANDARD_RTTIEXT(OpenGl_GraphicDriver, Graphic3d_GraphicDriver)
public:
  //! Constructor.
  //! @param theDisp connection to display, required on Linux but optional on other systems
  //! @param theToInitialize perform initialization of default OpenGL context on construction
  Standard_EXPORT OpenGl_GraphicDriver(const occ::handle<Aspect_DisplayConnection>& theDisp,
                                       const bool theToInitialize = true);

  //! Destructor.
  Standard_EXPORT ~OpenGl_GraphicDriver() override;

  //! Release default context.
  Standard_EXPORT void ReleaseContext();

  //! Perform initialization of default OpenGL context.
  Standard_EXPORT bool InitContext();

  //! Initialize default OpenGL context using existing one.
  //! @param theEglDisplay EGL connection to the Display
  //! @param theEglContext EGL rendering context
  //! @param theEglConfig  EGL configuration
  Standard_EXPORT bool InitEglContext(Aspect_Display          theEglDisplay,
                                      Aspect_RenderingContext theEglContext,
                                      void*                   theEglConfig);

  //! Request limit of graphic resource of specific type.
  Standard_EXPORT int InquireLimit(const Graphic3d_TypeOfLimit theType) const override;

public:
  Standard_EXPORT occ::handle<Graphic3d_CStructure> CreateStructure(
    const occ::handle<Graphic3d_StructureManager>& theManager) override;

  Standard_EXPORT void RemoveStructure(occ::handle<Graphic3d_CStructure>& theCStructure) override;

  Standard_EXPORT occ::handle<Graphic3d_CView> CreateView(
    const occ::handle<Graphic3d_StructureManager>& theMgr) override;

  Standard_EXPORT void RemoveView(const occ::handle<Graphic3d_CView>& theView) override;

  //! Create OpenGL window from native window.
  //! @param[in] theNativeWindow native window holder
  //! @param[in] theSizeWindow object defining window dimensions
  //! @param[in] theContext existing native rendering context
  Standard_EXPORT virtual occ::handle<OpenGl_Window> CreateRenderWindow(
    const occ::handle<Aspect_Window>& theNativeWindow,
    const occ::handle<Aspect_Window>& theSizeWindow,
    const Aspect_RenderingContext     theContext);

public:
  Standard_EXPORT void TextSize(const occ::handle<Graphic3d_CView>& theView,
                                const char* const                   theText,
                                const float                         theHeight,
                                float&                              theWidth,
                                float&                              theAscent,
                                float&                              theDescent) const override;

  Standard_EXPORT float DefaultTextHeight() const override;

  Standard_EXPORT bool ViewExists(const occ::handle<Aspect_Window>& theWindow,
                                  occ::handle<Graphic3d_CView>&     theView) override;

public:
  //! Adds a layer to all views.
  //! @param[in] theNewLayerId id of new layer, should be > 0 (negative values are reserved for
  //! default layers).
  //! @param[in] theSettings   new layer settings
  //! @param[in] theLayerAfter id of layer to append new layer before
  Standard_EXPORT void InsertLayerBefore(const Graphic3d_ZLayerId        theNewLayerId,
                                         const Graphic3d_ZLayerSettings& theSettings,
                                         const Graphic3d_ZLayerId        theLayerAfter) override;

  //! Adds a layer to all views.
  //! @param[in] theNewLayerId  id of created layer
  //! @param[in] theSettings    new layer settings
  //! @param[in] theLayerBefore id of layer to append new layer after
  Standard_EXPORT void InsertLayerAfter(const Graphic3d_ZLayerId        theNewLayerId,
                                        const Graphic3d_ZLayerSettings& theSettings,
                                        const Graphic3d_ZLayerId        theLayerBefore) override;

  //! Removes Z layer. All structures displayed at the moment in layer will be displayed in
  //! default layer (the bottom-level z layer). By default, there are always default
  //! bottom-level layer that can't be removed. The passed theLayerId should be not less than 0
  //! (reserved for default layers that can not be removed).
  Standard_EXPORT void RemoveZLayer(const Graphic3d_ZLayerId theLayerId) override;

  //! Sets the settings for a single Z layer.
  Standard_EXPORT void SetZLayerSettings(const Graphic3d_ZLayerId        theLayerId,
                                         const Graphic3d_ZLayerSettings& theSettings) override;

public:
  //! @return the visualization options
  inline const OpenGl_Caps& Options() const { return *myCaps.operator->(); }

  //! @return the visualization options
  inline OpenGl_Caps& ChangeOptions() { return *myCaps.operator->(); }

  //! Specify swap buffer behavior.
  Standard_EXPORT void SetBuffersNoSwap(const bool theIsNoSwap);

  //! VBO usage can be forbidden by this method even if it is supported by GL driver.
  //! Notice that disabling of VBO will cause rendering performance degradation.
  //! Warning! This method should be called only before any primitives are displayed in GL scene!
  Standard_EXPORT void EnableVBO(const bool theToTurnOn) override;

  //! Returns TRUE if vertical synchronization with display refresh rate (VSync) should be used;
  //! TRUE by default.
  Standard_EXPORT bool IsVerticalSync() const override;

  //! Set if vertical synchronization with display refresh rate (VSync) should be used.
  Standard_EXPORT void SetVerticalSync(bool theToEnable) override;

  //! Returns information about GPU memory usage.
  //! Please read OpenGl_Context::MemoryInfo() for more description.
  Standard_EXPORT bool MemoryInfo(size_t&                  theFreeBytes,
                                  TCollection_AsciiString& theInfo) const override;

public:
  //! Method to retrieve valid GL context.
  //! Could return NULL-handle if no window created by this driver.
  //! @param theBound if TRUE then currently bound context will be returned,
  //!                 any context will be returned otherwise
  Standard_EXPORT const occ::handle<OpenGl_Context>& GetSharedContext(bool theBound = false) const;

  Aspect_Display getRawGlDisplay() const { return myEglDisplay; }

  Aspect_RenderingContext getRawGlContext() const { return myEglContext; }

  void* getRawGlConfig() const { return myEglConfig; }

  //! Set device lost flag for redrawn views.
  Standard_EXPORT void setDeviceLost();

public:
  //! State counter for OpenGl structures.
  OpenGl_StateCounter* GetStateCounter() const { return &myStateCounter; }

  //! Returns unique ID for primitive arrays.
  size_t GetNextPrimitiveArrayUID() const { return myUIDGenerator.Increment(); }

protected:
  //! Choose default visual for new windows created by Aspect_DisplayConnection.
  Standard_EXPORT void chooseVisualInfo();

protected:
  // clang-format off
  bool        myIsOwnContext; //!< indicates that shared context has been created within OpenGl_GraphicDriver
  // clang-format on

  Aspect_Display          myEglDisplay; //!< EGL connection to the Display : EGLDisplay
  Aspect_RenderingContext myEglContext; //!< EGL rendering context         : EGLContext
  void*                   myEglConfig;  //!< EGL configuration             : EGLConfig

  occ::handle<OpenGl_Caps>                    myCaps;
  NCollection_Map<occ::handle<OpenGl_View>>   myMapOfView;
  NCollection_DataMap<int, OpenGl_Structure*> myMapOfStructure;

  mutable OpenGl_StateCounter myStateCounter; //!< State counter for OpenGl structures.
  mutable OpenGl_StateCounter myUIDGenerator; //!< Unique ID counter for primitive arrays.
};

#endif //_OpenGl_GraphicDriver_HeaderFile