/*

   Simple DirectMedia Layer

   Copyright (C) 1997-2011 Sam Lantinga <slouken@libsdl.org>

   This software is provided 'as-is', without any express or implied

   warranty.  In no event will the authors be held liable for any damages

   arising from the use of this software.

   Permission is granted to anyone to use this software for any purpose,

   including commercial applications, and to alter it and redistribute it

   freely, subject to the following restrictions:

   1. The origin of this software must not be misrepresented; you must not

      claim that you wrote the original software. If you use this software

      in a product, an acknowledgment in the product documentation would be

      appreciated but is not required.

   2. Altered source versions must be plainly marked as such, and must not be

      misrepresented as being the original software.

   3. This notice may not be removed or altered from any source distribution.

 */

 #include "SDL_DirectFB_video.h"

 #if SDL_DIRECTFB_OPENGL

 #include "SDL_DirectFB_opengl.h"

 #include "SDL_DirectFB_window.h"

 #include <directfbgl.h>

 #include "SDL_loadso.h"

 #endif

 #if SDL_DIRECTFB_OPENGL

 struct SDL_GLDriverData

 {

     int gl_active;              /* to stop switching drivers while we have a valid context */

     int initialized;

     DirectFB_GLContext *firstgl;        /* linked list */

     /* OpenGL */

     void (*glFinish) (void);

     void (*glFlush) (void);

 };

 #define OPENGL_REQUIRS_DLOPEN

 #if defined(OPENGL_REQUIRS_DLOPEN) && defined(SDL_LOADSO_DLOPEN)

 #include <dlfcn.h>

 #define GL_LoadObject(X)	dlopen(X, (RTLD_NOW|RTLD_GLOBAL))

 #define GL_LoadFunction		dlsym

 #define GL_UnloadObject		dlclose

 #else

 #define GL_LoadObject	SDL_LoadObject

 #define GL_LoadFunction	SDL_LoadFunction

 #define GL_UnloadObject	SDL_UnloadObject

 #endif

 static void DirectFB_GL_UnloadLibrary(_THIS);

 int

 DirectFB_GL_Initialize(_THIS)

 {

     if (_this->gl_data) {

         return 0;

     }

     _this->gl_data =

         (struct SDL_GLDriverData *) SDL_calloc(1,

                                                sizeof(struct

                                                       SDL_GLDriverData));

     if (!_this->gl_data) {

         SDL_OutOfMemory();

         return -1;

     }

     _this->gl_data->initialized = 0;

     ++_this->gl_data->initialized;

     _this->gl_data->firstgl = NULL;

     if (DirectFB_GL_LoadLibrary(_this, NULL) < 0) {

         return -1;

     }

     /* Initialize extensions */

     /* FIXME needed?

      * X11_GL_InitExtensions(_this);

      */

     return 0;

 }

 void

 DirectFB_GL_Shutdown(_THIS)

 {

     if (!_this->gl_data || (--_this->gl_data->initialized > 0)) {

         return;

     }

     DirectFB_GL_UnloadLibrary(_this);

     SDL_free(_this->gl_data);

     _this->gl_data = NULL;

 }

 int

 DirectFB_GL_LoadLibrary(_THIS, const char *path)

 {

     //SDL_DFB_DEVICEDATA(_this);

     void *handle = NULL;

     SDL_DFB_DEBUG("Loadlibrary : %s\n", path);

     if (_this->gl_data->gl_active) {

         SDL_SetError("OpenGL context already created");

         return -1;

     }

     if (path == NULL) {

         path = SDL_getenv("SDL_VIDEO_GL_DRIVER");

         if (path == NULL) {

             path = "libGL.so";

         }

     }

     handle = GL_LoadObject(path);

     if (handle == NULL) {

         SDL_DFB_ERR("Library not found: %s\n", path);

         /* SDL_LoadObject() will call SDL_SetError() for us. */

         return -1;

     }

     SDL_DFB_DEBUG("Loaded library: %s\n", path);

     _this->gl_config.dll_handle = handle;

     _this->gl_config.driver_loaded = 1;

     if (path) {

         SDL_strlcpy(_this->gl_config.driver_path, path,

                     SDL_arraysize(_this->gl_config.driver_path));

     } else {

         *_this->gl_config.driver_path = '\0';

     }

     _this->gl_data->glFinish = DirectFB_GL_GetProcAddress(_this, "glFinish");

     _this->gl_data->glFlush = DirectFB_GL_GetProcAddress(_this, "glFlush");

     return 0;

 }

 static void

 DirectFB_GL_UnloadLibrary(_THIS)

 {

  #if 0

     int ret;

     if (_this->gl_config.driver_loaded) {

         ret = GL_UnloadObject(_this->gl_config.dll_handle);

         if (ret)

             SDL_DFB_ERR("Error #%d trying to unload library.\n", ret);

         _this->gl_config.dll_handle = NULL;

         _this->gl_config.driver_loaded = 0;

     }

 #endif

     /* Free OpenGL memory */

     SDL_free(_this->gl_data);

     _this->gl_data = NULL;

 }

 void *

 DirectFB_GL_GetProcAddress(_THIS, const char *proc)

 {

     void *handle;

     handle = _this->gl_config.dll_handle;

     return GL_LoadFunction(handle, proc);

 }

 SDL_GLContext

 DirectFB_GL_CreateContext(_THIS, SDL_Window * window)

 {

     //SDL_DFB_DEVICEDATA(_this);

     SDL_DFB_WINDOWDATA(window);

     DirectFB_GLContext *context;

     SDL_DFB_ALLOC_CLEAR(context, sizeof(DirectFB_GLContext));

     SDL_DFB_CHECKERR(windata->surface->GetGL(windata->surface,

                                              &context->context));

     if (!context->context)

         return NULL;

     context->is_locked = 0;

     context->sdl_window = window;

     context->next = _this->gl_data->firstgl;

     _this->gl_data->firstgl = context;

     SDL_DFB_CHECK(context->context->Unlock(context->context));

     if (DirectFB_GL_MakeCurrent(_this, window, context) < 0) {

         DirectFB_GL_DeleteContext(_this, context);

         return NULL;

     }

     return context;

   error:

     return NULL;

 }

 int

 DirectFB_GL_MakeCurrent(_THIS, SDL_Window * window, SDL_GLContext context)

 {

     //SDL_DFB_WINDOWDATA(window);

     DirectFB_GLContext *ctx = (DirectFB_GLContext *) context;

     DirectFB_GLContext *p;

     for (p = _this->gl_data->firstgl; p; p = p->next)

     {

        if (p->is_locked) {

          SDL_DFB_CHECKERR(p->context->Unlock(p->context));

          p->is_locked = 0;

        }

     }

     if (ctx != NULL) {

         SDL_DFB_CHECKERR(ctx->context->Lock(ctx->context));

         ctx->is_locked = 1;

     }

     return 0;

   error:

     return -1;

 }

 int

 DirectFB_GL_SetSwapInterval(_THIS, int interval)

 {

     SDL_Unsupported();

     return -1;

 }

 int

 DirectFB_GL_GetSwapInterval(_THIS)

 {

     SDL_Unsupported();

     return -1;

 }

 void

 DirectFB_GL_SwapWindow(_THIS, SDL_Window * window)

 {

     //SDL_DFB_DEVICEDATA(_this);

     SDL_DFB_WINDOWDATA(window);

     DFBRegion region;

     DirectFB_GLContext *p;

     region.x1 = 0;

     region.y1 = 0;

     region.x2 = window->w;

     region.y2 = window->h;

 #if 0

     if (devdata->glFinish)

         devdata->glFinish();

     else if (devdata->glFlush)

         devdata->glFlush();

 #endif

   	for (p = _this->gl_data->firstgl; p != NULL; p = p->next)

         if (p->sdl_window == window && p->is_locked)

         {

             SDL_DFB_CHECKERR(p->context->Unlock(p->context));

             p->is_locked = 0;

         }            

     SDL_DFB_CHECKERR(windata->window_surface->Flip(windata->window_surface,NULL,  DSFLIP_PIPELINE |DSFLIP_BLIT | DSFLIP_ONSYNC ));

     //if (windata->gl_context) {

         //SDL_DFB_CHECKERR(windata->surface->Flip(windata->surface,NULL, DSFLIP_ONSYNC)); 

         //SDL_DFB_CHECKERR(windata->gl_context->context->Lock(windata->gl_context->context));

     //}

     return;

   error:

     return;

 }

 void

 DirectFB_GL_DeleteContext(_THIS, SDL_GLContext context)

 {

     DirectFB_GLContext *ctx = (DirectFB_GLContext *) context;

     DirectFB_GLContext *p;

     if (ctx->is_locked)

         SDL_DFB_CHECK(ctx->context->Unlock(ctx->context));

     SDL_DFB_RELEASE(ctx->context);

     for (p = _this->gl_data->firstgl; p && p->next != ctx; p = p->next)

         ;

     if (p)

         p->next = ctx->next;

     else

         _this->gl_data->firstgl = ctx->next;

     SDL_DFB_FREE(ctx);

 }

 void

 DirectFB_GL_FreeWindowContexts(_THIS, SDL_Window * window)

 {

     DirectFB_GLContext *p;

 	for (p = _this->gl_data->firstgl; p != NULL; p = p->next)

 	    if (p->sdl_window == window)

 	    {

 	    	if (p->is_locked)

 	        	SDL_DFB_CHECK(p->context->Unlock(p->context));

 	        SDL_DFB_RELEASE(p->context);

 	    }

 }

 void

 DirectFB_GL_ReAllocWindowContexts(_THIS, SDL_Window * window)

 {

     DirectFB_GLContext *p;

 	for (p = _this->gl_data->firstgl; p != NULL; p = p->next)

 	    if (p->sdl_window == window)

 	    {

             SDL_DFB_WINDOWDATA(window);

 			SDL_DFB_CHECK(windata->surface->GetGL(windata->surface,

 	                                         &p->context));

     		if (p->is_locked)

             	SDL_DFB_CHECK(p->context->Lock(p->context));

 	        }

 }

 void

 DirectFB_GL_DestroyWindowContexts(_THIS, SDL_Window * window)

 {

     DirectFB_GLContext *p;

 	for (p = _this->gl_data->firstgl; p != NULL; p = p->next)

 		if (p->sdl_window == window)

 			DirectFB_GL_DeleteContext(_this, p);

 }

 #endif

 /* vi: set ts=4 sw=4 expandtab: */