// Copyright (c) 2013-2014 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 Aspect_DisplayConnection_HeaderFile
#define Aspect_DisplayConnection_HeaderFile

#include "Standard_Transient.hxx"
#include "Aspect_XAtom.hxx"
#include "Aspect_FBConfig.hxx"

#include "TCollection_AsciiString.hxx"
#include "NCollection_DataMap.hxx"

struct Aspect_XDisplay;
struct Aspect_XVisualInfo;

//! This class creates and provides connection with X server.
//! Raises exception if can not connect to X server.
//! On Windows and Mac OS X (in case when Cocoa used) platforms this class does nothing.
//! WARNING: Do not close display connection manually!
class Aspect_DisplayConnection : public Standard_Transient
{
  DEFINE_STANDARD_RTTIEXT(Aspect_DisplayConnection, Standard_Transient)
public:
  //! Default constructor. Creates connection with display name taken from "DISPLAY" environment
  //! variable
  Standard_EXPORT Aspect_DisplayConnection();

  //! Destructor. Close opened connection.
  Standard_EXPORT ~Aspect_DisplayConnection() override;

  //! Constructor. Creates connection with display specified in theDisplayName.
  //! Display name should be in format "hostname:number" or "hostname:number.screen_number", where:
  //! hostname
  //!   - Specifies the name of the host machine on which the display is physically attached.
  //! number
  //!   - Specifies the number of the display server on that host machine.
  //! screen_number
  //!   - Specifies the screen to be used on that server. Optional variable.
  Standard_EXPORT Aspect_DisplayConnection(const TCollection_AsciiString& theDisplayName);

  //! Constructor wrapping existing Display instance.
  //! WARNING! it is a responsibility of application to keep this pointer
  //! valid while Aspect_DisplayConnection is alive and to close Display when it is no more needed.
  Standard_EXPORT Aspect_DisplayConnection(Aspect_XDisplay* theDisplay);

  //! @return pointer to Display structure that serves as the connection to the X server.
  Aspect_XDisplay* GetDisplayAspect() { return myDisplay; }

  //! @return TRUE if X Display has been allocated by this class
  bool IsOwnDisplay() const { return myIsOwnDisplay; }

  //! @return identifier(atom) for custom named property associated with windows that use current
  //! connection to X server.
  uint64_t GetAtom(const Aspect_XAtom theAtom) const { return myAtoms.Find(theAtom); }

  //! @return display name for this connection.
  const TCollection_AsciiString& GetDisplayName() { return myDisplayName; }

  //! Open connection with display specified in myDisplayName class field
  //! or takes theDisplay parameter when it is not NULL.
  //! WARNING! When external Display is specified, it is a responsibility of application
  //! to keep this pointer valid while Aspect_DisplayConnection is alive
  //! and to close Display when it is no more needed.
  //! @param theDisplay external pointer to allocated Display, or NULL if new connection should be
  //! created
  Standard_EXPORT void Init(Aspect_XDisplay* theDisplay);

  //! Return default window visual or NULL when undefined.
  Aspect_XVisualInfo* GetDefaultVisualInfo() const { return myDefVisualInfo; }

  //! @return native Window FB config (GLXFBConfig on Xlib)
  Aspect_FBConfig GetDefaultFBConfig() const { return myDefFBConfig; }

  //! Set default window visual; the visual will be deallocated using XFree().
  Standard_EXPORT void SetDefaultVisualInfo(Aspect_XVisualInfo* theVisual,
                                            Aspect_FBConfig     theFBConfig);

#ifdef X_PROTOCOL
  //! Constructor wrapping existing Display instance.
  //! WARNING! it is a responsibility of application to keep this pointer
  //! valid while Aspect_DisplayConnection is alive and to close Display when it is no more needed.
  Aspect_DisplayConnection(Display* theDisplay)
      : Aspect_DisplayConnection((Aspect_XDisplay*)theDisplay)
  {
  }

  //! @return pointer to Display structure that serves as the connection to the X server.
  Display* GetDisplay() { return (Display*)myDisplay; }

  //! Return default window visual or NULL when undefined.
  XVisualInfo* GetDefaultVisualInfoX() const { return (XVisualInfo*)myDefVisualInfo; }

  //! Set default window visual; the visual will be deallocated using XFree().
  void SetDefaultVisualInfo(XVisualInfo* theVisual, Aspect_FBConfig theFBConfig)
  {
    SetDefaultVisualInfo((Aspect_XVisualInfo*)theVisual, theFBConfig);
  }

  //! @return identifier(atom) for custom named property associated with windows that use current
  //! connection to X server.
  Atom GetAtomX(const Aspect_XAtom theAtom) const { return (Atom)GetAtom(theAtom); }

  //! Open connection with display specified in myDisplayName class field
  //! or takes theDisplay parameter when it is not NULL.
  void Init(Display* theDisplay) { Init((Aspect_XDisplay*)theDisplay); }
#endif

private:
  Aspect_XDisplay*                            myDisplay;
  Aspect_XVisualInfo*                         myDefVisualInfo;
  Aspect_FBConfig                             myDefFBConfig;
  NCollection_DataMap<Aspect_XAtom, uint64_t> myAtoms;
  TCollection_AsciiString                     myDisplayName;
  bool                                        myIsOwnDisplay;

private:
  //! To protect the connection from closing copying allowed only through the handles.
  Aspect_DisplayConnection(const Aspect_DisplayConnection&)            = delete;
  Aspect_DisplayConnection& operator=(const Aspect_DisplayConnection&) = delete;
};

#endif // _Aspect_DisplayConnection_H__