/*
 * Cogl
 *
 * A Low Level GPU Graphics and Utilities API
 *
 * Copyright (C) 2011 Intel Corporation.
 *
 * Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation
 * files (the "Software"), to deal in the Software without
 * restriction, including without limitation the rights to use, copy,
 * modify, merge, publish, distribute, sublicense, and/or sell copies
 * of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 *
 *
 * Authors:
 *  Robert Bragg <robert@linux.intel.com>
 *
 */

#include "cogl-config.h"

#include "cogl-renderer-private.h"
#include "cogl-display-private.h"
#include "cogl-context-private.h"
#include "cogl-framebuffer-private.h"
#include "cogl-private.h"
#include "winsys/cogl-winsys-stub-private.h"

#include <string.h>

static int _cogl_winsys_stub_dummy_ptr;

/* This provides a NOP winsys. This can be useful for debugging or for
 * integrating with toolkits that already have window system
 * integration code.
 */

static GCallback
_cogl_winsys_renderer_get_proc_address (CoglRenderer *renderer,
                                        const char *name,
                                        gboolean in_core)
{
  static GModule *module = NULL;

  /* this should find the right function if the program is linked against a
   * library providing it */
  if (G_UNLIKELY (module == NULL))
    module = g_module_open (NULL, 0);

  if (module)
    {
      void *symbol;

      if (g_module_symbol (module, name, &symbol))
        return symbol;
    }

  return NULL;
}

static void
_cogl_winsys_renderer_disconnect (CoglRenderer *renderer)
{
  renderer->winsys = NULL;
}

static gboolean
_cogl_winsys_renderer_connect (CoglRenderer *renderer,
                               CoglError **error)
{
  renderer->winsys = &_cogl_winsys_stub_dummy_ptr;
  return TRUE;
}

static void
_cogl_winsys_display_destroy (CoglDisplay *display)
{
  display->winsys = NULL;
}

static gboolean
_cogl_winsys_display_setup (CoglDisplay *display,
                            CoglError **error)
{
  display->winsys = &_cogl_winsys_stub_dummy_ptr;
  return TRUE;
}

static gboolean
_cogl_winsys_context_init (CoglContext *context, CoglError **error)
{
  context->winsys = &_cogl_winsys_stub_dummy_ptr;

  if (!_cogl_context_update_features (context, error))
    return FALSE;

  memset (context->winsys_features, 0, sizeof (context->winsys_features));

  return TRUE;
}

static void
_cogl_winsys_context_deinit (CoglContext *context)
{
  context->winsys = NULL;
}

static gboolean
_cogl_winsys_onscreen_init (CoglOnscreen *onscreen,
                            CoglError **error)
{
  return TRUE;
}

static void
_cogl_winsys_onscreen_deinit (CoglOnscreen *onscreen)
{
}

static void
_cogl_winsys_onscreen_bind (CoglOnscreen *onscreen)
{
}

static void
_cogl_winsys_onscreen_swap_buffers_with_damage (CoglOnscreen *onscreen,
                                                const int *rectangles,
                                                int n_rectangles)
{
}

static void
_cogl_winsys_onscreen_set_visibility (CoglOnscreen *onscreen,
                                      gboolean visibility)
{
}

const CoglWinsysVtable *
_cogl_winsys_stub_get_vtable (void)
{
  static gboolean vtable_inited = FALSE;
  static CoglWinsysVtable vtable;

  /* It would be nice if we could use C99 struct initializers here
     like the GLX backend does. However this code is more likely to be
     compiled using Visual Studio which (still!) doesn't support them
     so we initialize it in code instead */

  if (!vtable_inited)
    {
      memset (&vtable, 0, sizeof (vtable));

      vtable.id = COGL_WINSYS_ID_STUB;
      vtable.name = "STUB";
      vtable.renderer_get_proc_address = _cogl_winsys_renderer_get_proc_address;
      vtable.renderer_connect = _cogl_winsys_renderer_connect;
      vtable.renderer_disconnect = _cogl_winsys_renderer_disconnect;
      vtable.display_setup = _cogl_winsys_display_setup;
      vtable.display_destroy = _cogl_winsys_display_destroy;
      vtable.context_init = _cogl_winsys_context_init;
      vtable.context_deinit = _cogl_winsys_context_deinit;

      vtable.onscreen_init = _cogl_winsys_onscreen_init;
      vtable.onscreen_deinit = _cogl_winsys_onscreen_deinit;
      vtable.onscreen_bind = _cogl_winsys_onscreen_bind;
      vtable.onscreen_swap_buffers_with_damage =
        _cogl_winsys_onscreen_swap_buffers_with_damage;
      vtable.onscreen_set_visibility = _cogl_winsys_onscreen_set_visibility;

      vtable_inited = TRUE;
    }

  return &vtable;
}
