/*  RetroArch - A frontend for libretro.
 *  Copyright (C) 2010-2014 - Hans-Kristian Arntzen
 *
 *  RetroArch is free software: you can redistribute it and/or modify it under the terms
 *  of the GNU General Public License as published by the Free Software Found-
 *  ation, either version 3 of the License, or (at your option) any later version.
 *
 *  RetroArch 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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along with RetroArch.
 *  If not, see <http://www.gnu.org/licenses/>.
 */

#ifndef __GFX_CONTEXT_H
#define __GFX_CONTEXT_H

#include "../boolean.h"
#include "../driver.h"

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

#ifdef __cplusplus
extern "C" {
#endif

#define MAX_EGLIMAGE_TEXTURES 32

enum gfx_ctx_api
{
   GFX_CTX_OPENGL_API,
   GFX_CTX_OPENGL_ES_API,
   GFX_CTX_DIRECT3D8_API,
   GFX_CTX_DIRECT3D9_API,
   GFX_CTX_OPENVG_API
};

typedef void (*gfx_ctx_proc_t)(void);

/* The opaque void* argument should be the overlying driver data 
 * (e.g. gl_t for OpenGL contexts).
 *
 * This will allow us in the future to have separate contexts 
 * to separate gl_t structs (if needed).
 *
 * For now, this is only relevant for D3D. */

typedef struct gfx_ctx_driver
{
   bool (*init)(void *data);
   void (*destroy)(void *data);

   /* Which API to bind to. */
   bool (*bind_api)(void *data, enum gfx_ctx_api,
         unsigned major, unsigned minor);

   /* Sets the swap interval. */
   void (*swap_interval)(void *data, unsigned);

   /* Sets video mode. Creates a window, etc. */
   bool (*set_video_mode)(void*, unsigned, unsigned, bool);

   /* Gets current window size.
    * If not initialized yet, it returns current screen size. */
   void (*get_video_size)(void*, unsigned*, unsigned*);

   /* Translates a window size to an aspect ratio.
    * In most cases this will be just width / height, but
    * some contexts will better know which actual aspect ratio is used.
    * This can be NULL to assume the default behavior.
    */
   float (*translate_aspect)(void*, unsigned, unsigned);

   /* Asks driver to update window title (FPS, etc). */
   void (*update_window_title)(void*);

   /* Queries for resize and quit events.
    * Also processes events. */
   void (*check_window)(void*, bool*, bool*,
         unsigned*, unsigned*, unsigned);

   /* Acknowledge a resize event. This is needed for some APIs. 
    * Most backends will ignore this. */
   void (*set_resize)(void*, unsigned, unsigned);

   /* Checks if window has input focus. */
   bool (*has_focus)(void*);

   /* Swaps buffers. VBlank sync depends on 
    * earlier calls to swap_interval. */
   void (*swap_buffers)(void*);

   /* Most video backends will want to use a certain input driver.
    * Checks for it here. */
   void (*input_driver)(void*, const input_driver_t**, void**);

   /* Wraps whatever gl_proc_address() there is.
    * Does not take opaque, to avoid lots of ugly wrapper code. */
   gfx_ctx_proc_t (*get_proc_address)(const char*);

#ifdef HAVE_EGL
   /* Returns true if this context supports EGLImage buffers for 
    * screen drawing and was initalized correctly. */
   bool (*init_egl_image_buffer)(void*, const video_info_t*);

   /* Writes the frame to the EGLImage and sets image_handle to it. 
    * Returns true if a new image handle is created.
    * Always returns true the first time it's called for a new index. 
    * The graphics core must handle a change in the handle correctly. */
   bool (*write_egl_image)(void*, const void *frame, unsigned width,
         unsigned height, unsigned pitch, bool rgb32,
         unsigned index, void **image_handle);
#endif

   /* Shows or hides mouse. Can be NULL if context doesn't 
    * have a concept of mouse pointer. */
   void (*show_mouse)(void*, bool state);

   /* Human readable string. */
   const char *ident;

   /* Optional. Binds HW-render offscreen context. */
   void (*bind_hw_render)(void *data, bool enable);
} gfx_ctx_driver_t;

extern const gfx_ctx_driver_t gfx_ctx_sdl_gl;
extern const gfx_ctx_driver_t gfx_ctx_x_egl;
extern const gfx_ctx_driver_t gfx_ctx_wayland;
extern const gfx_ctx_driver_t gfx_ctx_glx;
extern const gfx_ctx_driver_t gfx_ctx_d3d;
extern const gfx_ctx_driver_t gfx_ctx_drm_egl;
extern const gfx_ctx_driver_t gfx_ctx_mali_fbdev;
extern const gfx_ctx_driver_t gfx_ctx_vivante_fbdev;
extern const gfx_ctx_driver_t gfx_ctx_android;
extern const gfx_ctx_driver_t gfx_ctx_ps3;
extern const gfx_ctx_driver_t gfx_ctx_wgl;
extern const gfx_ctx_driver_t gfx_ctx_videocore;
extern const gfx_ctx_driver_t gfx_ctx_bbqnx;
extern const gfx_ctx_driver_t gfx_ctx_apple;
extern const gfx_ctx_driver_t gfx_ctx_emscripten;
extern const gfx_ctx_driver_t gfx_ctx_null;

/* Finds driver with ident. Does not initialize. */
const gfx_ctx_driver_t *gfx_ctx_find_driver(const char *ident);

/* Finds first suitable driver and initializes. */
const gfx_ctx_driver_t *gfx_ctx_init_first(void *data, enum gfx_ctx_api api, 
      unsigned major, unsigned minor, bool hw_render_ctx);

#ifdef __cplusplus
}
#endif

#endif