/*
 * X11DRV OpenGL functions
 *
 * Copyright 2000 Lionel Ulmer
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include "config.h"
#include "wine/port.h"

#include <stdlib.h>
#include <string.h>

#include "x11drv.h"
#include "wine/library.h"
#include "wine/debug.h"

WINE_DEFAULT_DEBUG_CHANNEL(opengl);

#if defined(HAVE_GL_GL_H) && defined(HAVE_GL_GLX_H)

#undef APIENTRY
#undef CALLBACK
#undef WINAPI

#define XMD_H /* This is to prevent the Xmd.h inclusion bug :-/ */
#ifdef HAVE_GL_GL_H
# include <GL/gl.h>
#endif
#ifdef HAVE_GL_GLX_H
# include <GL/glx.h>
#endif
#ifdef HAVE_GL_GLEXT_H
# include <GL/glext.h>
#endif
#undef  XMD_H

#undef APIENTRY
#undef CALLBACK
#undef WINAPI

/* Redefines the constants */
#define CALLBACK    __stdcall
#define WINAPI      __stdcall
#define APIENTRY    WINAPI


static void dump_PIXELFORMATDESCRIPTOR(const PIXELFORMATDESCRIPTOR *ppfd) {
  DPRINTF("  - size / version : %d / %d\n", ppfd->nSize, ppfd->nVersion);
  DPRINTF("  - dwFlags : ");
#define TEST_AND_DUMP(t,tv) if ((t) & (tv)) DPRINTF(#tv " ")
  TEST_AND_DUMP(ppfd->dwFlags, PFD_DEPTH_DONTCARE);
  TEST_AND_DUMP(ppfd->dwFlags, PFD_DOUBLEBUFFER);
  TEST_AND_DUMP(ppfd->dwFlags, PFD_DOUBLEBUFFER_DONTCARE);
  TEST_AND_DUMP(ppfd->dwFlags, PFD_DRAW_TO_WINDOW);
  TEST_AND_DUMP(ppfd->dwFlags, PFD_DRAW_TO_BITMAP);
  TEST_AND_DUMP(ppfd->dwFlags, PFD_GENERIC_ACCELERATED);
  TEST_AND_DUMP(ppfd->dwFlags, PFD_GENERIC_FORMAT);
  TEST_AND_DUMP(ppfd->dwFlags, PFD_NEED_PALETTE);
  TEST_AND_DUMP(ppfd->dwFlags, PFD_NEED_SYSTEM_PALETTE);
  TEST_AND_DUMP(ppfd->dwFlags, PFD_STEREO);
  TEST_AND_DUMP(ppfd->dwFlags, PFD_STEREO_DONTCARE);
  TEST_AND_DUMP(ppfd->dwFlags, PFD_SUPPORT_GDI);
  TEST_AND_DUMP(ppfd->dwFlags, PFD_SUPPORT_OPENGL);
  TEST_AND_DUMP(ppfd->dwFlags, PFD_SWAP_COPY);
  TEST_AND_DUMP(ppfd->dwFlags, PFD_SWAP_EXCHANGE);
  TEST_AND_DUMP(ppfd->dwFlags, PFD_SWAP_LAYER_BUFFERS);
#undef TEST_AND_DUMP
  DPRINTF("\n");

  DPRINTF("  - iPixelType : ");
  switch (ppfd->iPixelType) {
  case PFD_TYPE_RGBA: DPRINTF("PFD_TYPE_RGBA"); break;
  case PFD_TYPE_COLORINDEX: DPRINTF("PFD_TYPE_COLORINDEX"); break;
  }
  DPRINTF("\n");

  DPRINTF("  - Color   : %d\n", ppfd->cColorBits);
  DPRINTF("  - Alpha   : %d\n", ppfd->cAlphaBits);
  DPRINTF("  - Accum   : %d\n", ppfd->cAccumBits);
  DPRINTF("  - Depth   : %d\n", ppfd->cDepthBits);
  DPRINTF("  - Stencil : %d\n", ppfd->cStencilBits);
  DPRINTF("  - Aux     : %d\n", ppfd->cAuxBuffers);

  DPRINTF("  - iLayerType : ");
  switch (ppfd->iLayerType) {
  case PFD_MAIN_PLANE: DPRINTF("PFD_MAIN_PLANE"); break;
  case PFD_OVERLAY_PLANE: DPRINTF("PFD_OVERLAY_PLANE"); break;
  case PFD_UNDERLAY_PLANE: DPRINTF("PFD_UNDERLAY_PLANE"); break;
  }
  DPRINTF("\n");
}

/* No need to load any other libraries as according to the ABI, libGL should be self-sufficient and
   include all dependencies
*/
#ifndef SONAME_LIBGL
#define SONAME_LIBGL "libGL.so"
#endif

static void *opengl_handle;

#define MAKE_FUNCPTR(f) static typeof(f) * p##f;
MAKE_FUNCPTR(glXChooseVisual)
MAKE_FUNCPTR(glXGetConfig)
MAKE_FUNCPTR(glXSwapBuffers)
MAKE_FUNCPTR(glXQueryExtension)
#undef MAKE_FUNCPTR

void X11DRV_OpenGL_Init(Display *display) {
    int error_base, event_base;

    opengl_handle = wine_dlopen(SONAME_LIBGL, RTLD_NOW|RTLD_GLOBAL, NULL, 0);
    if (opengl_handle == NULL) return;

#define LOAD_FUNCPTR(f) if((p##f = wine_dlsym(opengl_handle, #f, NULL, 0)) == NULL) goto sym_not_found;
LOAD_FUNCPTR(glXChooseVisual)
LOAD_FUNCPTR(glXGetConfig)
LOAD_FUNCPTR(glXSwapBuffers)
LOAD_FUNCPTR(glXQueryExtension)
#undef LOAD_FUNCPTR

    wine_tsx11_lock();
    if (pglXQueryExtension(display, &event_base, &error_base) == True) {
	TRACE("GLX is up and running error_base = %d\n", error_base);
    } else {
        wine_dlclose(opengl_handle, NULL, 0);
	opengl_handle = NULL;
    }
    wine_tsx11_unlock();
    return;

sym_not_found:
    wine_dlclose(opengl_handle, NULL, 0);
    opengl_handle = NULL;
}

/* X11DRV_ChoosePixelFormat

     Equivalent of glXChooseVisual
*/
int X11DRV_ChoosePixelFormat(X11DRV_PDEVICE *physDev,
			     const PIXELFORMATDESCRIPTOR *ppfd) {
#define TEST_AND_ADD1(t,a) if (t) att_list[att_pos++] = a
#define TEST_AND_ADD2(t,a,b) if (t) { att_list[att_pos++] = a; att_list[att_pos++] = b; }
#define NULL_TEST_AND_ADD2(tv,a,b) att_list[att_pos++] = a; att_list[att_pos++] = ((tv) == 0 ? 0 : b)
#define ADD2(a,b) att_list[att_pos++] = a; att_list[att_pos++] = b

  int att_list[64];
  int att_pos = 0;
  XVisualInfo *vis;
  int i;

  if (opengl_handle == NULL) {
    ERR("No libGL on this box - disabling OpenGL support !\n");
    return 0;
  }
  
  if (TRACE_ON(opengl)) {
    TRACE("(%p,%p)\n", physDev, ppfd);

    dump_PIXELFORMATDESCRIPTOR((const PIXELFORMATDESCRIPTOR *) ppfd);
  }

  if (ppfd->dwFlags & PFD_DRAW_TO_BITMAP) {
    ERR("Flag not supported !\n");
    /* Should SetError here... */
    return 0;
  }

  /* Now, build the request to GLX */
  TEST_AND_ADD1(ppfd->dwFlags & PFD_DOUBLEBUFFER, GLX_DOUBLEBUFFER);
  TEST_AND_ADD1(ppfd->dwFlags & PFD_STEREO, GLX_STEREO);
  TEST_AND_ADD1(ppfd->iPixelType == PFD_TYPE_RGBA, GLX_RGBA);
  TEST_AND_ADD2(ppfd->iPixelType == PFD_TYPE_COLORINDEX, GLX_BUFFER_SIZE, ppfd->cColorBits);

  NULL_TEST_AND_ADD2(ppfd->cDepthBits, GLX_DEPTH_SIZE, 8);
  /* These flags are not supported yet...

     NULL_TEST_AND_ADD2(ppfd->cAlphaBits, GLX_ALPHA_SIZE, 8);
     ADD2(GLX_ACCUM_SIZE, ppfd->cAccumBits); */
  ADD2(GLX_STENCIL_SIZE, ppfd->cStencilBits); /* now supported */
  /*   ADD2(GLX_AUX_BUFFERS, ppfd->cAuxBuffers); */
  att_list[att_pos] = None;

  wine_tsx11_lock(); {
    /*
       This command cannot be used as we need to use the default visual...
       Let's hope it at least contains some OpenGL functionnalities

       vis = glXChooseVisual(gdi_display, DefaultScreen(gdi_display), att_list);
    */
    int num;
    XVisualInfo template;

    template.visualid = XVisualIDFromVisual(visual);
    vis = XGetVisualInfo(gdi_display, VisualIDMask, &template, &num);

    TRACE("Found visual : %p - returns %d\n", vis, physDev->used_visuals + 1);
  }
  wine_tsx11_unlock();

  if (vis == NULL) {
    ERR("No visual found !\n");
    /* Should SetError here... */
    return 0;
  }
  /* try to find the visualid in the already created visuals */
  for( i=0; i<physDev->used_visuals; i++ ) {
    if ( vis->visualid == physDev->visuals[i]->visualid ) {
      XFree(vis);
      return i+1;
    }
  }
  /* now give up, if the maximum is reached */
  if (physDev->used_visuals == MAX_PIXELFORMATS) {
    ERR("Maximum number of visuals reached !\n");
    /* Should SetError here... */
    return 0;
  }
  physDev->visuals[physDev->used_visuals++] = vis;

  return physDev->used_visuals;
}

/* X11DRV_DescribePixelFormat

     Get the pixel-format descriptor associated to the given id
*/
int X11DRV_DescribePixelFormat(X11DRV_PDEVICE *physDev,
			       int iPixelFormat,
			       UINT nBytes,
			       PIXELFORMATDESCRIPTOR *ppfd) {
  XVisualInfo *vis;
  int value;
  int rb,gb,bb,ab;

  if (opengl_handle == NULL) {
    ERR("No libGL on this box - disabling OpenGL support !\n");
    return 0;
  }
  
  TRACE("(%p,%d,%d,%p)\n", physDev, iPixelFormat, nBytes, ppfd);

  if (ppfd == NULL) {
    /* The application is only querying the number of visuals */
    return MAX_PIXELFORMATS;
  }

  if (nBytes < sizeof(PIXELFORMATDESCRIPTOR)) {
    ERR("Wrong structure size !\n");
    /* Should set error */
    return 0;
  }
  if ((iPixelFormat > MAX_PIXELFORMATS) ||
      (iPixelFormat > physDev->used_visuals + 1) ||
      (iPixelFormat <= 0)) {
    ERR("Wrong pixel format !\n");
    /* Should set error */
    return 0;
  }

  if (iPixelFormat == physDev->used_visuals + 1) {
    int dblBuf[]={GLX_RGBA,GLX_DEPTH_SIZE,16,GLX_DOUBLEBUFFER,None};

    /* Create a 'standard' X Visual */
    wine_tsx11_lock();
    vis = pglXChooseVisual(gdi_display, DefaultScreen(gdi_display), dblBuf);
    wine_tsx11_unlock();

    WARN("Uninitialized Visual. Creating standard (%p) !\n", vis);

    if (vis == NULL) {
      ERR("Could not create standard visual !\n");
      /* Should set error */
      return 0;
    }

    physDev->visuals[physDev->used_visuals++] = vis;
  }
  vis = physDev->visuals[iPixelFormat - 1];

  memset(ppfd, 0, sizeof(PIXELFORMATDESCRIPTOR));
  ppfd->nSize = sizeof(PIXELFORMATDESCRIPTOR);
  ppfd->nVersion = 1;

  /* These flags are always the same... */
  ppfd->dwFlags = PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL | PFD_GENERIC_ACCELERATED;
  /* Now the flags extraced from the Visual */
  wine_tsx11_lock();
  pglXGetConfig(gdi_display, vis, GLX_DOUBLEBUFFER, &value); if (value) ppfd->dwFlags |= PFD_DOUBLEBUFFER;
  pglXGetConfig(gdi_display, vis, GLX_STEREO, &value); if (value) ppfd->dwFlags |= PFD_STEREO;

  /* Pixel type */
  pglXGetConfig(gdi_display, vis, GLX_RGBA, &value);
  if (value)
    ppfd->iPixelType = PFD_TYPE_RGBA;
  else
    ppfd->iPixelType = PFD_TYPE_COLORINDEX;

  /* Color bits */
  pglXGetConfig(gdi_display, vis, GLX_BUFFER_SIZE, &value);
  ppfd->cColorBits = value;

  /* Red, green, blue and alpha bits / shifts */
  if (ppfd->iPixelType == PFD_TYPE_RGBA) {
    pglXGetConfig(gdi_display, vis, GLX_RED_SIZE, &rb);
    pglXGetConfig(gdi_display, vis, GLX_GREEN_SIZE, &gb);
    pglXGetConfig(gdi_display, vis, GLX_BLUE_SIZE, &bb);
    pglXGetConfig(gdi_display, vis, GLX_ALPHA_SIZE, &ab);

    ppfd->cRedBits = rb;
    ppfd->cRedShift = gb + bb + ab;
    ppfd->cBlueBits = bb;
    ppfd->cBlueShift = ab;
    ppfd->cGreenBits = gb;
    ppfd->cGreenShift = bb + ab;
    ppfd->cAlphaBits = ab;
    ppfd->cAlphaShift = 0;
  } else {
    ppfd->cRedBits = 0;
    ppfd->cRedShift = 0;
    ppfd->cBlueBits = 0;
    ppfd->cBlueShift = 0;
    ppfd->cGreenBits = 0;
    ppfd->cGreenShift = 0;
    ppfd->cAlphaBits = 0;
    ppfd->cAlphaShift = 0;
  }
  /* Accums : to do ... */

  /* Depth bits */
  pglXGetConfig(gdi_display, vis, GLX_DEPTH_SIZE, &value);
  ppfd->cDepthBits = value;

  /* stencil bits */
  pglXGetConfig( gdi_display, vis, GLX_STENCIL_SIZE, &value );
  ppfd->cStencilBits = value;

  wine_tsx11_unlock();

  /* Aux : to do ... */

  ppfd->iLayerType = PFD_MAIN_PLANE;

  if (TRACE_ON(opengl)) {
    dump_PIXELFORMATDESCRIPTOR(ppfd);
  }

  return MAX_PIXELFORMATS;
}

/* X11DRV_GetPixelFormat

     Get the pixel-format id used by this DC
*/
int X11DRV_GetPixelFormat(X11DRV_PDEVICE *physDev) {
  TRACE("(%p): returns %d\n", physDev, physDev->current_pf);

  return physDev->current_pf;
}

/* X11DRV_SetPixelFormat

     Set the pixel-format id used by this DC
*/
BOOL X11DRV_SetPixelFormat(X11DRV_PDEVICE *physDev,
			   int iPixelFormat,
			   const PIXELFORMATDESCRIPTOR *ppfd) {
  TRACE("(%p,%d,%p)\n", physDev, iPixelFormat, ppfd);

  physDev->current_pf = iPixelFormat;

  return TRUE;
}

/* X11DRV_SwapBuffers

     Swap the buffers of this DC
*/
BOOL X11DRV_SwapBuffers(X11DRV_PDEVICE *physDev) {
  if (opengl_handle == NULL) {
    ERR("No libGL on this box - disabling OpenGL support !\n");
    return 0;
  }
  
  TRACE("(%p)\n", physDev);

  wine_tsx11_lock();
  pglXSwapBuffers(gdi_display, physDev->drawable);
  wine_tsx11_unlock();

  return TRUE;
}

/***********************************************************************
 *		X11DRV_setup_opengl_visual
 *
 * Setup the default visual used for OpenGL and Direct3D, and the desktop
 * window (if it exists).  If OpenGL isn't available, the visual is simply
 * set to the default visual for the display
 */
XVisualInfo *X11DRV_setup_opengl_visual( Display *display )
{
    XVisualInfo *visual = NULL;
    int dblBuf[]={GLX_RGBA,GLX_DEPTH_SIZE,16,GLX_DOUBLEBUFFER,None};

    if (opengl_handle == NULL) return NULL;
    
    /* In order to support OpenGL or D3D, we require a double-buffered visual */
    wine_tsx11_lock();
    visual = pglXChooseVisual(display, DefaultScreen(display), dblBuf);
    wine_tsx11_unlock();
    return visual;
}

#else  /* no OpenGL includes */

void X11DRV_OpenGL_Init(Display *display)
{
}

/***********************************************************************
 *		ChoosePixelFormat (X11DRV.@)
 */
int X11DRV_ChoosePixelFormat(X11DRV_PDEVICE *physDev,
			     const PIXELFORMATDESCRIPTOR *ppfd) {
  ERR("No OpenGL support compiled in.\n");

  return 0;
}

/***********************************************************************
 *		DescribePixelFormat (X11DRV.@)
 */
int X11DRV_DescribePixelFormat(X11DRV_PDEVICE *physDev,
			       int iPixelFormat,
			       UINT nBytes,
			       PIXELFORMATDESCRIPTOR *ppfd) {
  ERR("No OpenGL support compiled in.\n");

  return 0;
}

/***********************************************************************
 *		GetPixelFormat (X11DRV.@)
 */
int X11DRV_GetPixelFormat(X11DRV_PDEVICE *physDev) {
  ERR("No OpenGL support compiled in.\n");

  return 0;
}

/***********************************************************************
 *		SetPixelFormat (X11DRV.@)
 */
BOOL X11DRV_SetPixelFormat(X11DRV_PDEVICE *physDev,
			   int iPixelFormat,
			   const PIXELFORMATDESCRIPTOR *ppfd) {
  ERR("No OpenGL support compiled in.\n");

  return FALSE;
}

/***********************************************************************
 *		SwapBuffers (X11DRV.@)
 */
BOOL X11DRV_SwapBuffers(X11DRV_PDEVICE *physDev) {
  ERR("No OpenGL support compiled in.\n");

  return FALSE;
}

XVisualInfo *X11DRV_setup_opengl_visual( Display *display )
{
  return NULL;
}

#endif /* defined(HAVE_OPENGL) */
