/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2006 Sam Lantinga

    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., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Sam Lantinga
    slouken@libsdl.org
*/
#include "SDL_config.h"

/* Dummy SDL video driver implementation; this is just enough to make an
 *  SDL-based application THINK it's got a working video driver, for
 *  applications that call SDL_Init(SDL_INIT_VIDEO) when they don't need it,
 *  and also for use as a collection of stubs when porting SDL to a new
 *  platform for which you haven't yet written a valid video driver.
 *
 * This is also a great way to determine bottlenecks: if you think that SDL
 *  is a performance problem for a given platform, enable this driver, and
 *  then see if your application runs faster without video overhead.
 *
 * Initial work by Ryan C. Gordon (icculus@icculus.org). A good portion
 *  of this was cut-and-pasted from Stephane Peter's work in the AAlib
 *  SDL video driver.  Renamed to "DUMMY" by Sam Lantinga.
 */

#include "SDL_video.h"
#include "SDL_mouse.h"
#include "../SDL_sysvideo.h"
#include "../SDL_pixels_c.h"
#include "../../events/SDL_events_c.h"

#include "SDL_nullvideo.h"
#include "SDL_nullevents_c.h"
#include "SDL_nullmouse_c.h"

#define DUMMYVID_DRIVER_NAME "dummy"

/* Initialization/Query functions */
static int DUMMY_VideoInit (_THIS);
static int DUMMY_SetDisplayMode (_THIS, const SDL_DisplayMode * mode);
static SDL_Surface *DUMMY_CreateWindowSurface (_THIS, SDL_Window * window);
static void DUMMY_VideoQuit (_THIS);

/* DUMMY driver bootstrap functions */

static int
DUMMY_Available (void)
{
    const char *envr = SDL_getenv ("SDL_VIDEODRIVER");
    if ((envr) && (SDL_strcmp (envr, DUMMYVID_DRIVER_NAME) == 0)) {
        return (1);
    }

    return (0);
}

static void
DUMMY_DeleteDevice (SDL_VideoDevice * device)
{
    SDL_free (device->hidden);
    SDL_free (device);
}

static SDL_VideoDevice *
DUMMY_CreateDevice (int devindex)
{
    SDL_VideoDevice *device;

    /* Initialize all variables that we clean on shutdown */
    device = (SDL_VideoDevice *) SDL_malloc (sizeof (SDL_VideoDevice));
    if (device) {
        SDL_memset (device, 0, (sizeof *device));
        device->hidden = (struct SDL_PrivateVideoData *)
            SDL_malloc ((sizeof *device->hidden));
    }
    if ((device == NULL) || (device->hidden == NULL)) {
        SDL_OutOfMemory ();
        if (device) {
            SDL_free (device);
        }
        return (0);
    }
    SDL_memset (device->hidden, 0, (sizeof *device->hidden));

    /* Set the function pointers */
    device->VideoInit = DUMMY_VideoInit;
    device->SetDisplayMode = DUMMY_SetDisplayMode;
    device->VideoQuit = DUMMY_VideoQuit;
    device->InitOSKeymap = DUMMY_InitOSKeymap;
    device->PumpEvents = DUMMY_PumpEvents;

    device->free = DUMMY_DeleteDevice;

    return device;
}

VideoBootStrap DUMMY_bootstrap = {
    DUMMYVID_DRIVER_NAME, "SDL dummy video driver",
    DUMMY_Available, DUMMY_CreateDevice
};


int
DUMMY_VideoInit (_THIS)
{
    SDL_AddBasicVideoDisplay (NULL);

    /* We're done! */
    return 0;
}

static int
DUMMY_SetDisplayMode (_THIS, const SDL_DisplayMode * mode)
{
    return 0;
}

static SDL_Surface *
DUMMY_CreateWindowSurface (_THIS, SDL_Window * window)
{
    int bpp;
    Uint32 Rmask, Gmask, Bmask, Amask;

    if (_this->hidden->buffer) {
        SDL_free (_this->hidden->buffer);
    }

    _this->hidden->buffer =
        SDL_malloc (mode->w * mode->h * SDL_BYTESPERPIXEL (mode->format));
    if (!_this->hidden->buffer) {
        SDL_SetError ("Couldn't allocate buffer for requested mode");
        return (NULL);
    }

/* 	printf("Setting mode %dx%d\n", width, height); */

    SDL_memset (_this->hidden->buffer, 0,
                mode->w * mode->h * SDL_BYTESPERPIXEL (mode->format));

    /* Allocate the new pixel format for the screen */
    SDL_PixelFormatEnumToMasks (mode->format, &bpp, &Rmask, &Gmask, &Bmask,
                                &Amask);
    if (!SDL_ReallocFormat (current, bpp, Rmask, Gmask, Bmask, Amask)) {
        SDL_free (_this->hidden->buffer);
        _this->hidden->buffer = NULL;
        SDL_SetError
            ("Couldn't allocate new pixel format for requested mode");
        return (NULL);
    }

    /* Set up the new mode framebuffer */
    current->flags = flags & SDL_FULLSCREEN;
    _this->hidden->w = current->w = mode->w;
    _this->hidden->h = current->h = mode->h;
    current->pitch = current->w * SDL_BYTESPERPIXEL (mode->format);
    current->pixels = _this->hidden->buffer;

    /* We're done */
    return (current);
}

SDL_Surface *
DUMMY_SetVideoMode (_THIS, SDL_Surface * current,
                    const SDL_DisplayMode * mode, Uint32 flags)
{
    int bpp;
    Uint32 Rmask, Gmask, Bmask, Amask;

    if (_this->hidden->buffer) {
        SDL_free (_this->hidden->buffer);
    }

    _this->hidden->buffer =
        SDL_malloc (mode->w * mode->h * SDL_BYTESPERPIXEL (mode->format));
    if (!_this->hidden->buffer) {
        SDL_SetError ("Couldn't allocate buffer for requested mode");
        return (NULL);
    }

/* 	printf("Setting mode %dx%d\n", width, height); */

    SDL_memset (_this->hidden->buffer, 0,
                mode->w * mode->h * SDL_BYTESPERPIXEL (mode->format));

    /* Allocate the new pixel format for the screen */
    SDL_PixelFormatEnumToMasks (mode->format, &bpp, &Rmask, &Gmask, &Bmask,
                                &Amask);
    if (!SDL_ReallocFormat (current, bpp, Rmask, Gmask, Bmask, Amask)) {
        SDL_free (_this->hidden->buffer);
        _this->hidden->buffer = NULL;
        SDL_SetError
            ("Couldn't allocate new pixel format for requested mode");
        return (NULL);
    }

    /* Set up the new mode framebuffer */
    current->flags = flags & SDL_FULLSCREEN;
    _this->hidden->w = current->w = mode->w;
    _this->hidden->h = current->h = mode->h;
    current->pitch = current->w * SDL_BYTESPERPIXEL (mode->format);
    current->pixels = _this->hidden->buffer;

    /* We're done */
    return (current);
}

/* Note:  If we are terminated, this could be called in the middle of
   another SDL video routine -- notably UpdateRects.
*/
void
DUMMY_VideoQuit (_THIS)
{
    if (_this->hidden->buffer) {
        SDL_free (_this->hidden->buffer);
    }
}

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