#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include "clutter-stage-egl.h"
#include "clutter-egl.h"
#include "clutter-backend-egl.h"

#include "../clutter-main.h"
#include "../clutter-feature.h"
#include "../clutter-color.h"
#include "../clutter-util.h"
#include "../clutter-event.h"
#include "../clutter-enum-types.h"
#include "../clutter-private.h"
#include "../clutter-debug.h"
#include "../clutter-units.h"
#include "../clutter-stage.h"
#include "../clutter-stage-window.h"

static void clutter_stage_window_iface_init (ClutterStageWindowIface *iface);

G_DEFINE_TYPE_WITH_CODE (ClutterStageEGL,
                         clutter_stage_egl,
                         CLUTTER_TYPE_ACTOR,
                         G_IMPLEMENT_INTERFACE (CLUTTER_TYPE_STAGE_WINDOW,
                                                clutter_stage_window_iface_init));

static void
clutter_stage_egl_show (ClutterActor *actor)
{
  CLUTTER_ACTOR_SET_FLAGS (actor, CLUTTER_ACTOR_MAPPED);
}

static void
clutter_stage_egl_hide (ClutterActor *actor)
{
  CLUTTER_ACTOR_UNSET_FLAGS (actor, CLUTTER_ACTOR_MAPPED);
}

static void
clutter_stage_egl_unrealize (ClutterActor *actor)
{
  ClutterStageEGL *stage_egl = CLUTTER_STAGE_EGL (actor);

  CLUTTER_MARK();

  CLUTTER_ACTOR_CLASS (clutter_stage_egl_parent_class)->unrealize (actor);

  if (stage_egl->egl_surface)
    {
      eglDestroySurface (clutter_egl_display (), stage_egl->egl_surface);
      stage_egl->egl_surface = EGL_NO_SURFACE;
    }
}

static void
clutter_stage_egl_realize (ClutterActor *actor)
{
  ClutterStageEGL     *stage_egl = CLUTTER_STAGE_EGL (actor);
  ClutterBackendEGL   *backend_egl;
  EGLConfig            configs[2];
  EGLint               config_count;
  EGLBoolean           status;
  gboolean             is_offscreen;

  CLUTTER_NOTE (BACKEND, "Realizing main stage");

  g_object_get (stage_egl->wrapper, "offscreen", &is_offscreen, NULL);

  backend_egl = CLUTTER_BACKEND_EGL (clutter_get_default_backend ());

  if (G_LIKELY (!is_offscreen))
    {
      EGLint cfg_attribs[] = { EGL_BUFFER_SIZE,     EGL_DONT_CARE,
			       EGL_RED_SIZE,        5,
			       EGL_GREEN_SIZE,      6,
			       EGL_BLUE_SIZE,       5,
			       EGL_DEPTH_SIZE,      16,
			       EGL_ALPHA_SIZE,      EGL_DONT_CARE,
			       EGL_STENCIL_SIZE,    2, 
#ifdef HAVE_COGL_GLES2
			       EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
#else /* HAVE_COGL_GLES2 */
			       EGL_SURFACE_TYPE,    EGL_WINDOW_BIT,
#endif /* HAVE_COGL_GLES2 */
			       EGL_NONE };

      status = eglGetConfigs (backend_egl->edpy,
			      configs, 
			      2, 
			      &config_count);

      if (status != EGL_TRUE)
        {
	  g_critical ("eglGetConfigs failed");
          CLUTTER_ACTOR_UNSET_FLAGS (actor, CLUTTER_ACTOR_REALIZED);
          return;
        }

      status = eglChooseConfig (backend_egl->edpy,
				cfg_attribs,
				configs,
                                G_N_ELEMENTS (configs),
				&config_count);

      if (status != EGL_TRUE)
        {
          g_critical ("eglChooseConfig failed");
          CLUTTER_ACTOR_UNSET_FLAGS (actor, CLUTTER_ACTOR_REALIZED);
          return;
        }

      CLUTTER_NOTE (BACKEND, "Got %i configs", config_count); 

      if (stage_egl->egl_surface != EGL_NO_SURFACE)
        {
	  eglDestroySurface (backend_egl->edpy, stage_egl->egl_surface);
          stage_egl->egl_surface = EGL_NO_SURFACE;
        }

       if (backend_egl->egl_context)
         {
            eglDestroyContext (backend_egl->edpy, backend_egl->egl_context);
            backend_egl->egl_context = NULL;
         }

      stage_egl->egl_surface =
	eglCreateWindowSurface (backend_egl->edpy,
                                configs[0],
                                NULL,
                                NULL);

      if (stage_egl->egl_surface == EGL_NO_SURFACE)
        {
	  g_critical ("Unable to create an EGL surface");

          CLUTTER_ACTOR_UNSET_FLAGS (actor, CLUTTER_ACTOR_REALIZED);
          return;
        }

      eglQuerySurface (backend_egl->edpy,
		       stage_egl->egl_surface,
		       EGL_WIDTH,
		       &stage_egl->surface_width);

      eglQuerySurface (backend_egl->edpy,
		       stage_egl->egl_surface,
		       EGL_HEIGHT,
		       &stage_egl->surface_height);

      CLUTTER_NOTE (BACKEND, "EGL surface is %ix%i", 
		    stage_egl->surface_width,
                    stage_egl->surface_height);

      
      if (G_UNLIKELY (backend_egl->egl_context == NULL))
        {
#ifdef HAVE_COGL_GLES2
	  static const EGLint attribs[3]
	    = { EGL_CONTEXT_CLIENT_VERSION, 2, EGL_NONE };

          backend_egl->egl_context = eglCreateContext (backend_egl->edpy,
						       configs[0],
                                                       EGL_NO_CONTEXT,
                                                       attribs);
#else
          /* Seems some GLES implementations 1.x do not like attribs... */
          backend_egl->egl_context = eglCreateContext (backend_egl->edpy,
						       configs[0],
                                                       EGL_NO_CONTEXT,
                                                       NULL);
#endif

          if (backend_egl->egl_context == EGL_NO_CONTEXT)
            {
              g_critical ("Unable to create a suitable EGL context");

              CLUTTER_ACTOR_UNSET_FLAGS (actor, CLUTTER_ACTOR_REALIZED);
              return;
            }

          CLUTTER_NOTE (GL, "Created EGL Context");
        }

      CLUTTER_NOTE (BACKEND, "Marking stage as realized and setting context");
      CLUTTER_ACTOR_SET_FLAGS (stage_egl, CLUTTER_ACTOR_REALIZED);

      /* eglnative can have only one stage */
      status = eglMakeCurrent (backend_egl->edpy,
                               stage_egl->egl_surface,
                               stage_egl->egl_surface,
                               backend_egl->egl_context);

      if (status != EGL_TRUE)
        {
          g_critical ("eglMakeCurrent failed");
          
          CLUTTER_ACTOR_UNSET_FLAGS (actor, CLUTTER_ACTOR_REALIZED);
          return;
        }

      /* since we only have one size and it cannot change, we
       * just need to update the GL viewport now that we have
       * been realized
       */
      CLUTTER_SET_PRIVATE_FLAGS (actor, CLUTTER_ACTOR_SYNC_MATRICES);
    }
  else
    {
      g_warning ("EGL Backend does not yet support offscreen rendering\n");
      CLUTTER_ACTOR_UNSET_FLAGS (actor, CLUTTER_ACTOR_REALIZED);
      return;
    }
}

static void
clutter_stage_egl_get_preferred_width (ClutterActor *self,
                                       ClutterUnit   for_height,
                                       ClutterUnit  *min_width_p,
                                       ClutterUnit  *natural_width_p)
{
  ClutterStageEGL *stage_egl = CLUTTER_STAGE_EGL (self);

  if (min_width_p)
    *min_width_p = CLUTTER_UNITS_FROM_DEVICE (stage_egl->surface_width);

  if (natural_width_p)
    *natural_width_p = CLUTTER_UNITS_FROM_DEVICE (stage_egl->surface_width);
}

static void
clutter_stage_egl_get_preferred_height (ClutterActor *self,
                                        ClutterUnit   for_width,
                                        ClutterUnit  *min_height_p,
                                        ClutterUnit  *natural_height_p)
{
  ClutterStageEGL *stage_egl = CLUTTER_STAGE_EGL (self);

  if (min_height_p)
    *min_height_p = CLUTTER_UNITS_FROM_DEVICE (stage_egl->surface_height);

  if (natural_height_p)
    *natural_height_p = CLUTTER_UNITS_FROM_DEVICE (stage_egl->surface_height);
}

static void
clutter_stage_egl_dispose (GObject *gobject)
{
  ClutterStageEGL *stage_egl = CLUTTER_STAGE_EGL (gobject);

  clutter_actor_unrealize (CLUTTER_ACTOR (stage_egl));

  G_OBJECT_CLASS (clutter_stage_egl_parent_class)->dispose (gobject);
}

static void
clutter_stage_egl_class_init (ClutterStageEGLClass *klass)
{
  GObjectClass      *gobject_class = G_OBJECT_CLASS (klass);
  ClutterActorClass *actor_class   = CLUTTER_ACTOR_CLASS (klass);

  gobject_class->dispose = clutter_stage_egl_dispose;

  actor_class->show                 = clutter_stage_egl_show;
  actor_class->hide                 = clutter_stage_egl_hide;
  actor_class->realize              = clutter_stage_egl_realize;
  actor_class->unrealize            = clutter_stage_egl_unrealize;
  actor_class->get_preferred_width  = clutter_stage_egl_get_preferred_width;
  actor_class->get_preferred_height = clutter_stage_egl_get_preferred_height;
}

static void
clutter_stage_egl_set_fullscreen (ClutterStageWindow *stage_window,
                                  gboolean            fullscreen)
{
  g_warning ("Stage of type `%s' do not support ClutterStage::set_fullscreen",
             G_OBJECT_TYPE_NAME (stage_window));
}

static ClutterActor *
clutter_stage_egl_get_wrapper (ClutterStageWindow *stage_window)
{
  return CLUTTER_ACTOR (CLUTTER_STAGE_EGL (stage_window)->wrapper);
}

static void
clutter_stage_window_iface_init (ClutterStageWindowIface *iface)
{
  iface->set_fullscreen = clutter_stage_egl_set_fullscreen;
  iface->set_title = NULL;
  iface->get_wrapper = clutter_stage_egl_get_wrapper;
}

static void
clutter_stage_egl_init (ClutterStageEGL *stage)
{
}