/*

    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

*/

/* 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@linuxgames.com). 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, SDL_PixelFormat *vformat);

static SDL_Rect **DUMMY_ListModes(_THIS, SDL_PixelFormat *format, Uint32 flags);

static SDL_Surface *DUMMY_SetVideoMode(_THIS, SDL_Surface *current, int width, int height, int bpp, Uint32 flags);

static int DUMMY_SetColors(_THIS, int firstcolor, int ncolors, SDL_Color *colors);

static void DUMMY_VideoQuit(_THIS);

/* Hardware surface functions */

static int DUMMY_AllocHWSurface(_THIS, SDL_Surface *surface);

static int DUMMY_LockHWSurface(_THIS, SDL_Surface *surface);

static void DUMMY_UnlockHWSurface(_THIS, SDL_Surface *surface);

static void DUMMY_FreeHWSurface(_THIS, SDL_Surface *surface);

/* etc. */

static void DUMMY_UpdateRects(_THIS, int numrects, SDL_Rect *rects);

/* 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->ListModes = DUMMY_ListModes;

	device->SetVideoMode = DUMMY_SetVideoMode;

	device->CreateYUVOverlay = NULL;

	device->SetColors = DUMMY_SetColors;

	device->UpdateRects = DUMMY_UpdateRects;

	device->VideoQuit = DUMMY_VideoQuit;

	device->AllocHWSurface = DUMMY_AllocHWSurface;

	device->CheckHWBlit = NULL;

	device->FillHWRect = NULL;

	device->SetHWColorKey = NULL;

	device->SetHWAlpha = NULL;

	device->LockHWSurface = DUMMY_LockHWSurface;

	device->UnlockHWSurface = DUMMY_UnlockHWSurface;

	device->FlipHWSurface = NULL;

	device->FreeHWSurface = DUMMY_FreeHWSurface;

	device->SetCaption = NULL;

	device->SetIcon = NULL;

	device->IconifyWindow = NULL;

	device->GrabInput = NULL;

	device->GetWMInfo = NULL;

	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_PixelFormat *vformat)

{

	/*

	fprintf(stderr, "WARNING: You are using the SDL dummy video driver!\n");

	*/

	/* Determine the screen depth (use default 8-bit depth) */

	/* we change this during the SDL_SetVideoMode implementation... */

	vformat->BitsPerPixel = 8;

	vformat->BytesPerPixel = 1;

	/* We're done! */

	return(0);

}

SDL_Rect **DUMMY_ListModes(_THIS, SDL_PixelFormat *format, Uint32 flags)

{

   	 return (SDL_Rect **) -1;

}

SDL_Surface *DUMMY_SetVideoMode(_THIS, SDL_Surface *current,

				int width, int height, int bpp, Uint32 flags)

{

	if ( this->hidden->buffer ) {

		SDL_free( this->hidden->buffer );

	}

	this->hidden->buffer = SDL_malloc(width * height * (bpp / 8));

	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, width * height * (bpp / 8));

	/* Allocate the new pixel format for the screen */

	if ( ! SDL_ReallocFormat(current, bpp, 0, 0, 0, 0) ) {

		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 = width;

	this->hidden->h = current->h = height;

	current->pitch = current->w * (bpp / 8);

	current->pixels = this->hidden->buffer;

	/* We're done */

	return(current);

}

/* We don't actually allow hardware surfaces other than the main one */

static int DUMMY_AllocHWSurface(_THIS, SDL_Surface *surface)

{

	return(-1);

}

static void DUMMY_FreeHWSurface(_THIS, SDL_Surface *surface)

{

	return;

}

/* We need to wait for vertical retrace on page flipped displays */

static int DUMMY_LockHWSurface(_THIS, SDL_Surface *surface)

{

	return(0);

}

static void DUMMY_UnlockHWSurface(_THIS, SDL_Surface *surface)

{

	return;

}

static void DUMMY_UpdateRects(_THIS, int numrects, SDL_Rect *rects)

{

	/* do nothing. */

}

int DUMMY_SetColors(_THIS, int firstcolor, int ncolors, SDL_Color *colors)

{

	/* do nothing of note. */

	return(1);

}

/* 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->screen->pixels != NULL)

	{

		SDL_free(this->screen->pixels);

		this->screen->pixels = NULL;

	}

}