/*
    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"

/*
 * Xbios SDL video driver
 * 
 * Patrice Mandin
 */

#include <sys/stat.h>
#include <unistd.h>

/* Mint includes */
#include <mint/cookie.h>
#include <mint/osbind.h>
#include <mint/falcon.h>

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

#include "../ataricommon/SDL_ataric2p_s.h"
#include "../ataricommon/SDL_atarievents_c.h"
#include "../ataricommon/SDL_atarimxalloc_c.h"
#include "../ataricommon/SDL_atarigl_c.h"
#include "SDL_xbios.h"
#include "SDL_xbios_blowup.h"
#include "SDL_xbios_centscreen.h"
#include "SDL_xbios_sb3.h"

/* Debug print info */
#if 0
#define DEBUG_PRINT(what) \
	{ \
		printf what; \
	}
#define DEBUG_VIDEO_XBIOS 1
#else
#define DEBUG_PRINT(what)
#undef DEBUG_VIDEO_XBIOS
#endif

/* Initialization/Query functions */
static int XBIOS_VideoInit(_THIS);
static void XBIOS_VideoQuit(_THIS);

#if 0
static SDL_Rect **XBIOS_ListModes(_THIS, SDL_PixelFormat * format,
                                  Uint32 flags);
static SDL_Surface *XBIOS_SetVideoMode(_THIS, SDL_Surface * current,
                                       int width, int height, int bpp,
                                       Uint32 flags);
static int XBIOS_SetColors(_THIS, int firstcolor, int ncolors,
                           SDL_Color * colors);

/* Hardware surface functions */
static int XBIOS_AllocHWSurface(_THIS, SDL_Surface * surface);
static int XBIOS_LockHWSurface(_THIS, SDL_Surface * surface);
static int XBIOS_FlipHWSurface(_THIS, SDL_Surface * surface);
static void XBIOS_UnlockHWSurface(_THIS, SDL_Surface * surface);
static void XBIOS_FreeHWSurface(_THIS, SDL_Surface * surface);
static void XBIOS_UpdateRects(_THIS, int numrects, SDL_Rect * rects);

#if SDL_VIDEO_OPENGL
/* OpenGL functions */
static void XBIOS_GL_SwapBuffers(_THIS);
#endif

/* To setup palette */

static unsigned short TT_palette[256];
static unsigned long F30_palette[256];
#endif

/* Xbios driver bootstrap functions */

static int
XBIOS_Available(void)
{
    unsigned long cookie_vdo, cookie_mil, cookie_hade, cookie_scpn;

    /* Milan/Hades Atari clones do not have an Atari video chip */
    if ((Getcookie(C__MIL, &cookie_mil) == C_FOUND) ||
        (Getcookie(C_hade, &cookie_hade) == C_FOUND)) {
        return 0;
    }

    /* Cookie _VDO present ? if not, assume ST machine */
    if (Getcookie(C__VDO, &cookie_vdo) != C_FOUND) {
        cookie_vdo = VDO_ST << 16;
    }

    /* Test if we have a monochrome monitor plugged in */
    switch (cookie_vdo >> 16) {
    case VDO_ST:
    case VDO_STE:
        if (Getrez() == (ST_HIGH >> 8))
            return 0;
        break;
    case VDO_TT:
        if ((EgetShift() & ES_MODE) == TT_HIGH)
            return 0;
        break;
    case VDO_F30:
        if (VgetMonitor() == MONITOR_MONO)
            return 0;
        if (Getcookie(C_SCPN, &cookie_scpn) == C_FOUND) {
            if (!SDL_XBIOS_SB3Usable((scpn_cookie_t *) cookie_scpn)) {
                return 0;
            }
        }
        break;
    default:
        return 0;
    }

    return 1;
}

static void
XBIOS_DeleteDevice(SDL_VideoDevice * device)
{
    SDL_free(device->driverdata);
    SDL_free(device);
}

static SDL_VideoDevice *
XBIOS_CreateDevice(int devindex)
{
    SDL_VideoDevice *device;
    SDL_VideoData *data;

    /* Initialize all variables that we clean on shutdown */
    device = (SDL_VideoDevice *) SDL_calloc(1, sizeof(SDL_VideoDevice));
    if (device) {
        data = (struct SDL_VideoData *) SDL_calloc(1, sizeof(SDL_VideoData));
    }
    if (!device || !data) {
        SDL_OutOfMemory();
        if (device) {
            SDL_free(device);
        }
        return NULL;
    }
    device->driverdata = data;

    /* Video functions */
    device->VideoInit = XBIOS_VideoInit;
    device->VideoQuit = XBIOS_VideoQuit;

    /* Modes */
    device->GetDisplayModes = NULL /*XBIOS_GetDisplayModes */ ;
    device->SetDisplayMode = NULL /*XBIOS_SetDisplayMode */ ;

    /* Events */
    device->PumpEvents = SDL_Atari_PumpEvents;

#if SDL_VIDEO_OPENGL
    /* OpenGL functions */
    device->GL_LoadLibrary = SDL_AtariGL_LoadLibrary;
    device->GL_GetProcAddress = SDL_AtariGL_GetProcAddress;
    device->GL_CreateContext = NULL;
    device->GL_MakeCurrent = SDL_AtariGL_MakeCurrent;
    device->GL_SetSwapInterval = NULL;
    device->GL_GetSwapInterval = NULL;
    device->GL_SwapWindow = XBIOS_GL_SwapBuffers;
    device->GL_DeleteContext = NULL;
#endif

    device->free = XBIOS_DeleteDevice;

    return device;
}

VideoBootStrap XBIOS_bootstrap = {
    "xbios", "Atari Xbios driver",
    XBIOS_Available, XBIOS_CreateDevice
};

#if 0
void
SDL_XBIOS_AddMode(_THIS, Uint16 modecode, Uint16 width, Uint16 height,
                  Uint16 depth, SDL_bool flags)
{
    int i, curpos;
    xbiosmode_t *current_mode;

    /* Check if mode already exists */
    if (XBIOS_modelist) {
        current_mode = XBIOS_modelist;
        for (i = 0; i < XBIOS_nummodes; i++, current_mode++) {
            if (current_mode->width != width)
                continue;
            if (current_mode->height != height)
                continue;
            if (current_mode->depth != depth)
                continue;
            return;
        }
    }

    ++XBIOS_nummodes;
    XBIOS_modelist =
        (xbiosmode_t *) SDL_realloc(XBIOS_modelist,
                                    XBIOS_nummodes * sizeof(xbiosmode_t));

    /* Keep the list sorted: bpp, width, height */
    curpos = 0;

    for (i = 0; i < XBIOS_nummodes - 1; i++) {
        if (XBIOS_modelist[i].depth <= depth) {
            if (XBIOS_modelist[i].width < width) {
                break;
            } else if (XBIOS_modelist[i].width == width) {
                if (XBIOS_modelist[i].height <= height) {
                    break;
                }
            }
        }
        curpos++;
    }

    /* Push remaining modes further */
    for (i = XBIOS_nummodes - 1; i > curpos; i--) {
        SDL_memcpy(&XBIOS_modelist[i], &XBIOS_modelist[i - 1],
                   sizeof(xbiosmode_t));
    }

    XBIOS_modelist[curpos].number = modecode;
    XBIOS_modelist[curpos].width = width;
    XBIOS_modelist[curpos].height = height;
    XBIOS_modelist[curpos].depth = depth;
    XBIOS_modelist[curpos].doubleline = flags;
}
#endif

static int
XBIOS_VideoInit(_THIS)
{
    XBIOS_InitModes(_this);

#if 0
    int i, j8, j16;
    xbiosmode_t *current_mode;
    unsigned long cookie_blow, cookie_scpn, cookie_cnts;

    /* Initialize all variables that we clean on shutdown */
    memset(SDL_modelist, 0, sizeof(SDL_modelist));

    /* Cookie _VDO present ? if not, assume ST machine */
    if (Getcookie(C__VDO, &XBIOS_cvdo) != C_FOUND) {
        XBIOS_cvdo = VDO_ST << 16;
    }

    /* Allocate memory for old palette */
    XBIOS_oldpalette = (void *) SDL_malloc(256 * sizeof(long));
    if (!XBIOS_oldpalette) {
        SDL_SetError("Unable to allocate memory for old palette\n");
        return (-1);
    }

    /* Initialize video mode list */
    /* and save current screen status (palette, screen address, video mode) */
    XBIOS_nummodes = 0;
    XBIOS_modelist = NULL;
    XBIOS_centscreen = SDL_FALSE;

    switch (XBIOS_cvdo >> 16) {
    case VDO_ST:
    case VDO_STE:
        {
            short *oldpalette;

            SDL_XBIOS_AddMode(this, ST_LOW >> 8, 320, 200, 4, SDL_FALSE);

            XBIOS_oldvbase = Physbase();
            XBIOS_oldvmode = Getrez();
            switch (XBIOS_oldvmode << 8) {
            case ST_LOW:
                XBIOS_oldnumcol = 16;
                break;
            case ST_MED:
                XBIOS_oldnumcol = 4;
                break;
            case ST_HIGH:
                XBIOS_oldnumcol = 2;
                break;
            default:
                XBIOS_oldnumcol = 0;
                break;
            }

            oldpalette = (short *) XBIOS_oldpalette;
            for (i = 0; i < XBIOS_oldnumcol; i++) {
                *oldpalette++ = Setcolor(i, -1);
            }

            vformat->BitsPerPixel = 8;
        }
        break;
    case VDO_TT:

        SDL_XBIOS_AddMode(this, TT_LOW, 320, 480, 8, SDL_FALSE);
        /* Software double-lined mode */
        SDL_XBIOS_AddMode(this, TT_LOW, 320, 240, 8, SDL_TRUE);

        XBIOS_oldvbase = Logbase();
        XBIOS_oldvmode = EgetShift();

        switch (XBIOS_oldvmode & ES_MODE) {
        case TT_LOW:
            XBIOS_oldnumcol = 256;
            break;
        case ST_LOW:
        case TT_MED:
            XBIOS_oldnumcol = 16;
            break;
        case ST_MED:
            XBIOS_oldnumcol = 4;
            break;
        case ST_HIGH:
        case TT_HIGH:
            XBIOS_oldnumcol = 2;
            break;
        default:
            XBIOS_oldnumcol = 0;
            break;
        }
        if (XBIOS_oldnumcol) {
            EgetPalette(0, XBIOS_oldnumcol, XBIOS_oldpalette);
        }

        vformat->BitsPerPixel = 8;
        break;
    case VDO_F30:
        switch (VgetMonitor()) {
        case MONITOR_MONO:
            /* Not usable */
            break;
        case MONITOR_RGB:
        case MONITOR_TV:
            SDL_XBIOS_AddMode(this, BPS16 | COL80 | OVERSCAN | VERTFLAG,
                              768, 480, 16, SDL_FALSE);
            SDL_XBIOS_AddMode(this, BPS16 | COL80 | OVERSCAN, 768, 240,
                              16, SDL_FALSE);
            SDL_XBIOS_AddMode(this, BPS16 | COL80 | VERTFLAG, 640, 400,
                              16, SDL_FALSE);
            SDL_XBIOS_AddMode(this, BPS16 | COL80, 640, 200, 16, SDL_FALSE);
            SDL_XBIOS_AddMode(this, BPS16 | OVERSCAN | VERTFLAG, 384,
                              480, 16, SDL_FALSE);
            SDL_XBIOS_AddMode(this, BPS16 | OVERSCAN, 384, 240, 16,
                              SDL_FALSE);
            SDL_XBIOS_AddMode(this, BPS16 | VERTFLAG, 320, 400, 16,
                              SDL_FALSE);
            SDL_XBIOS_AddMode(this, BPS16, 320, 200, 16, SDL_FALSE);
            SDL_XBIOS_AddMode(this, BPS8 | COL80 | OVERSCAN | VERTFLAG,
                              768, 480, 8, SDL_FALSE);
            SDL_XBIOS_AddMode(this, BPS8 | COL80 | OVERSCAN, 768, 240, 8,
                              SDL_FALSE);
            SDL_XBIOS_AddMode(this, BPS8 | COL80 | VERTFLAG, 640, 400, 8,
                              SDL_FALSE);
            SDL_XBIOS_AddMode(this, BPS8 | COL80, 640, 200, 8, SDL_FALSE);
            SDL_XBIOS_AddMode(this, BPS8 | OVERSCAN | VERTFLAG, 384, 480,
                              8, SDL_FALSE);
            SDL_XBIOS_AddMode(this, BPS8 | OVERSCAN, 384, 240, 8, SDL_FALSE);
            SDL_XBIOS_AddMode(this, BPS8 | VERTFLAG, 320, 400, 8, SDL_FALSE);
            SDL_XBIOS_AddMode(this, BPS8, 320, 200, 8, SDL_FALSE);
            break;
        case MONITOR_VGA:
            SDL_XBIOS_AddMode(this, BPS16, 320, 480, 16, SDL_FALSE);
            SDL_XBIOS_AddMode(this, BPS16 | VERTFLAG, 320, 240, 16,
                              SDL_FALSE);
            SDL_XBIOS_AddMode(this, BPS8 | COL80, 640, 480, 8, SDL_FALSE);
            SDL_XBIOS_AddMode(this, BPS8 | COL80 | VERTFLAG, 640, 240, 8,
                              SDL_FALSE);
            SDL_XBIOS_AddMode(this, BPS8, 320, 480, 8, SDL_FALSE);
            SDL_XBIOS_AddMode(this, BPS8 | VERTFLAG, 320, 240, 8, SDL_FALSE);
            break;
        }
        XBIOS_oldvbase = Logbase();
        XBIOS_oldvmode = VsetMode(-1);

        XBIOS_oldnumcol = 1 << (1 << (XBIOS_oldvmode & NUMCOLS));
        if (XBIOS_oldnumcol > 256) {
            XBIOS_oldnumcol = 0;
        }
        if (XBIOS_oldnumcol) {
            VgetRGB(0, XBIOS_oldnumcol, XBIOS_oldpalette);
        }

        vformat->BitsPerPixel = 16;

        /* Keep vga/rvb, and pal/ntsc bits */
        current_mode = XBIOS_modelist;
        for (i = 0; i < XBIOS_nummodes; i++) {
            Uint16 newvmode;

            newvmode = current_mode->number;
            newvmode &= ~(VGA | PAL);
            newvmode |= XBIOS_oldvmode & (VGA | PAL);
            current_mode->number = newvmode;

            current_mode++;
        }

        /* Initialize BlowUp/SB3/Centscreen stuff if present */
        if (Getcookie(C_BLOW, &cookie_blow) == C_FOUND) {
            SDL_XBIOS_BlowupInit(this, (blow_cookie_t *) cookie_blow);
        } else if (Getcookie(C_SCPN, &cookie_scpn) == C_FOUND) {
            SDL_XBIOS_SB3Init(this, (scpn_cookie_t *) cookie_scpn);
        } else if (Getcookie(C_CNTS, &cookie_cnts) == C_FOUND) {
            XBIOS_oldvmode = SDL_XBIOS_CentscreenInit(this);
            XBIOS_centscreen = SDL_TRUE;
        }

        break;
    }

    /* Determine the current screen size */
    if (XBIOS_nummodes > 0) {
        /* FIXME: parse video mode list to search for current mode */
        this->info.current_w = XBIOS_modelist[0].width;
        this->info.current_h = XBIOS_modelist[0].height;
    }

    current_mode = XBIOS_modelist;
    j8 = j16 = 0;
    for (i = 0; i < XBIOS_nummodes; i++, current_mode++) {
        switch (current_mode->depth) {
        case 4:
        case 8:
            SDL_modelist[0][j8] = SDL_malloc(sizeof(SDL_Rect));
            SDL_modelist[0][j8]->x = SDL_modelist[0][j8]->y = 0;
            SDL_modelist[0][j8]->w = current_mode->width;
            SDL_modelist[0][j8]->h = current_mode->height;
            XBIOS_videomodes[0][j8] = current_mode;
            j8++;
            break;
        case 16:
            SDL_modelist[1][j16] = SDL_malloc(sizeof(SDL_Rect));
            SDL_modelist[1][j16]->x = SDL_modelist[1][j16]->y = 0;
            SDL_modelist[1][j16]->w = current_mode->width;
            SDL_modelist[1][j16]->h = current_mode->height;
            XBIOS_videomodes[1][j16] = current_mode;
            j16++;
            break;
        }
    }
    SDL_modelist[0][j8] = NULL;
    SDL_modelist[1][j16] = NULL;

    XBIOS_screens[0] = NULL;
    XBIOS_screens[1] = NULL;
    XBIOS_shadowscreen = NULL;

    /* Update hardware info */
    this->info.hw_available = 1;
    this->info.video_mem = (Uint32) Atari_SysMalloc(-1L, MX_STRAM);

    /* Init chunky to planar routine */
    SDL_Atari_C2pConvert = SDL_Atari_C2pConvert8;

#if SDL_VIDEO_OPENGL
    SDL_AtariGL_InitPointers(this);
#endif

#endif

    return (0);
}

static void
XBIOS_VideoQuit(_THIS)
{
/*    int i, j;*/

    XBIOS_QuitModes(_this);
    Atari_ShutdownEvents();

#if 0
    /* Restore video mode and palette */
#ifndef DEBUG_VIDEO_XBIOS
    switch (XBIOS_cvdo >> 16) {
    case VDO_ST:
    case VDO_STE:
        Setscreen(-1, XBIOS_oldvbase, XBIOS_oldvmode);
        if (XBIOS_oldnumcol) {
            Setpalette(XBIOS_oldpalette);
        }
        break;
    case VDO_TT:
        Setscreen(-1, XBIOS_oldvbase, -1);
        EsetShift(XBIOS_oldvmode);
        if (XBIOS_oldnumcol) {
            EsetPalette(0, XBIOS_oldnumcol, XBIOS_oldpalette);
        }
        break;
    case VDO_F30:
        Setscreen(-1, XBIOS_oldvbase, -1);
        if (XBIOS_centscreen) {
            SDL_XBIOS_CentscreenRestore(this, XBIOS_oldvmode);
        } else {
            VsetMode(XBIOS_oldvmode);
        }
        if (XBIOS_oldnumcol) {
            VsetRGB(0, XBIOS_oldnumcol, XBIOS_oldpalette);
        }
        break;
    }
    Vsync();
#endif


#if SDL_VIDEO_OPENGL
    if (gl_active) {
        SDL_AtariGL_Quit(this, SDL_TRUE);
    }
#endif

    if (XBIOS_oldpalette) {
        SDL_free(XBIOS_oldpalette);
        XBIOS_oldpalette = NULL;
    }
    XBIOS_FreeBuffers(this);

    /* Free mode list */
    for (j = 0; j < NUM_MODELISTS; j++) {
        for (i = 0; i < SDL_NUMMODES; i++) {
            if (SDL_modelist[j][i] != NULL) {
                SDL_free(SDL_modelist[j][i]);
                SDL_modelist[j][i] = NULL;
            }
        }
    }

    if (XBIOS_modelist) {
        SDL_free(XBIOS_modelist);
        XBIOS_nummodes = 0;
        XBIOS_modelist = NULL;
    }

    this->screen->pixels = NULL;
#endif
}

#if 0
static SDL_Rect **
XBIOS_ListModes(_THIS, SDL_PixelFormat * format, Uint32 flags)
{
    /* 8 bits -> list 0 */
    /* 16 bits -> list 1 */
    if ((format->BitsPerPixel != 8) && (format->BitsPerPixel != 16)) {
        return NULL;
    }

    return (SDL_modelist[(format->BitsPerPixel) >> 4]);
}

static void
XBIOS_FreeBuffers(_THIS)
{
    int i;

    for (i = 0; i < 2; i++) {
        if (XBIOS_screensmem[i] != NULL) {
            Mfree(XBIOS_screensmem[i]);
            XBIOS_screensmem[i] = NULL;
        }
    }

    if (XBIOS_shadowscreen != NULL) {
        Mfree(XBIOS_shadowscreen);
        XBIOS_shadowscreen = NULL;
    }
}

static SDL_Surface *
XBIOS_SetVideoMode(_THIS, SDL_Surface * current,
                   int width, int height, int bpp, Uint32 flags)
{
    int mode, new_depth;
    int i;
    xbiosmode_t *new_video_mode;
    Uint32 new_screen_size;
    Uint32 modeflags;

    /* Free current buffers */
    XBIOS_FreeBuffers(this);

    /* Limit bpp */
    if (bpp > 16) {
        bpp = 16;
    }
    bpp >>= 4;

    /* Search if the mode exists (width, height, bpp) */
    for (mode = 0; SDL_modelist[bpp][mode]; ++mode) {
        if ((SDL_modelist[bpp][mode]->w == width) &&
            (SDL_modelist[bpp][mode]->h == height)) {

            break;
        }
    }
    if (SDL_modelist[bpp][mode] == NULL) {
        SDL_SetError("Couldn't find requested mode in list");
        return (NULL);
    }

    modeflags = SDL_FULLSCREEN | SDL_PREALLOC;

    /* Allocate needed buffers: simple/double buffer and shadow surface */
    new_video_mode = XBIOS_videomodes[bpp][mode];
    new_depth = new_video_mode->depth;
    if (new_depth == 4) {
        SDL_Atari_C2pConvert = SDL_Atari_C2pConvert4;
        new_depth = 8;
        modeflags |= SDL_SWSURFACE | SDL_HWPALETTE;
    } else if (new_depth == 8) {
        SDL_Atari_C2pConvert = SDL_Atari_C2pConvert8;
        modeflags |= SDL_SWSURFACE | SDL_HWPALETTE;
    } else {
        modeflags |= SDL_HWSURFACE;
    }

    new_screen_size = width * height * ((new_depth) >> 3);
    new_screen_size += 256;     /* To align on a 256 byte adress */

    if (new_depth == 8) {
        XBIOS_shadowscreen = Atari_SysMalloc(new_screen_size, MX_PREFTTRAM);

        if (XBIOS_shadowscreen == NULL) {
            SDL_SetError("Can not allocate %d KB for shadow buffer",
                         new_screen_size >> 10);
            return (NULL);
        }
        SDL_memset(XBIOS_shadowscreen, 0, new_screen_size);
    }

    /* Output buffer needs to be twice in size for the software double-line mode */
    XBIOS_doubleline = SDL_FALSE;
    if (new_video_mode->doubleline) {
        new_screen_size <<= 1;
        XBIOS_doubleline = SDL_TRUE;
    }

    XBIOS_screensmem[0] = Atari_SysMalloc(new_screen_size, MX_STRAM);

    if (XBIOS_screensmem[0] == NULL) {
        XBIOS_FreeBuffers(this);
        SDL_SetError("Can not allocate %d KB for frame buffer",
                     new_screen_size >> 10);
        return (NULL);
    }
    SDL_memset(XBIOS_screensmem[0], 0, new_screen_size);

    XBIOS_screens[0] =
        (void *) (((long) XBIOS_screensmem[0] + 256) & 0xFFFFFF00UL);

#if SDL_VIDEO_OPENGL
    if (flags & SDL_INTERNALOPENGL) {
        if (this->gl_config.double_buffer) {
            flags |= SDL_DOUBLEBUF;
        }
    }
#endif

    /* Double buffer ? */
    if (flags & SDL_DOUBLEBUF) {
        XBIOS_screensmem[1] = Atari_SysMalloc(new_screen_size, MX_STRAM);

        if (XBIOS_screensmem[1] == NULL) {
            XBIOS_FreeBuffers(this);
            SDL_SetError("Can not allocate %d KB for double buffer",
                         new_screen_size >> 10);
            return (NULL);
        }
        SDL_memset(XBIOS_screensmem[1], 0, new_screen_size);

        XBIOS_screens[1] =
            (void *) (((long) XBIOS_screensmem[1] + 256) & 0xFFFFFF00UL);
        modeflags |= SDL_DOUBLEBUF;
    }

    /* Allocate the new pixel format for the screen */
    if (!SDL_ReallocFormat(current, new_depth, 0, 0, 0, 0)) {
        XBIOS_FreeBuffers(this);
        SDL_SetError("Couldn't allocate new pixel format for requested mode");
        return (NULL);
    }

    current->w = XBIOS_width = width;
    current->h = XBIOS_height = height;
    current->pitch = (width * new_depth) >> 3;

    /* this is for C2P conversion */
    XBIOS_pitch = (new_video_mode->width * new_video_mode->depth) >> 3;

    if (new_depth == 8)
        current->pixels = XBIOS_shadowscreen;
    else
        current->pixels = XBIOS_screens[0];

    XBIOS_fbnum = 0;

#if SDL_VIDEO_OPENGL
    if (flags & SDL_INTERNALOPENGL) {
        if (!SDL_AtariGL_Init(this, current)) {
            XBIOS_FreeBuffers(this);
            SDL_SetError("Can not create OpenGL context");
            return NULL;
        }

        modeflags |= SDL_INTERNALOPENGL;
    }
#endif

    current->flags = modeflags;

    /* Now set the video mode */
#ifndef DEBUG_VIDEO_XBIOS
    Setscreen(-1, XBIOS_screens[0], -1);
#endif

    switch (XBIOS_cvdo >> 16) {
    case VDO_ST:
#ifndef DEBUG_VIDEO_XBIOS
        Setscreen(-1, -1, new_video_mode->number);
#endif
        /* Reset palette */
        for (i = 0; i < 16; i++) {
            TT_palette[i] =
                ((i >> 1) << 8) | (((i * 8) / 17) << 4) | (i >> 1);
        }
#ifndef DEBUG_VIDEO_XBIOS
        Setpalette(TT_palette);
#endif
        break;
    case VDO_STE:
#ifndef DEBUG_VIDEO_XBIOS
        Setscreen(-1, -1, new_video_mode->number);
#endif
        /* Reset palette */
        for (i = 0; i < 16; i++) {
            int c;

            c = ((i & 1) << 3) | ((i >> 1) & 7);
            TT_palette[i] = (c << 8) | (c << 4) | c;
        }
#ifndef DEBUG_VIDEO_XBIOS
        Setpalette(TT_palette);
#endif
        break;
    case VDO_TT:
#ifndef DEBUG_VIDEO_XBIOS
        EsetShift(new_video_mode->number);
#endif
        break;
    case VDO_F30:
#ifndef DEBUG_VIDEO_XBIOS
        if (XBIOS_centscreen) {
            SDL_XBIOS_CentscreenSetmode(this, width, height, new_depth);
        } else {
            VsetMode(new_video_mode->number);
        }
#endif
        /* Set hardware palette to black in True Colour */
        if (new_depth == 16) {
            SDL_memset(F30_palette, 0, sizeof(F30_palette));
            VsetRGB(0, 256, F30_palette);
        }
        break;
    }

    Vsync();

    this->UpdateRects = XBIOS_UpdateRects;

    return (current);
}

/* We don't actually allow hardware surfaces other than the main one */
static int
XBIOS_AllocHWSurface(_THIS, SDL_Surface * surface)
{
    return (-1);
}

static void
XBIOS_FreeHWSurface(_THIS, SDL_Surface * surface)
{
    return;
}

static int
XBIOS_LockHWSurface(_THIS, SDL_Surface * surface)
{
    return (0);
}

static void
XBIOS_UnlockHWSurface(_THIS, SDL_Surface * surface)
{
    return;
}

static void
XBIOS_UpdateRects(_THIS, int numrects, SDL_Rect * rects)
{
    SDL_Surface *surface;

    surface = this->screen;

    if ((surface->format->BitsPerPixel) == 8) {
        int i;

        for (i = 0; i < numrects; i++) {
            void *source, *destination;
            int x1, x2;

            x1 = rects[i].x & ~15;
            x2 = rects[i].x + rects[i].w;
            if (x2 & 15) {
                x2 = (x2 | 15) + 1;
            }

            source = surface->pixels;
            source += surface->pitch * rects[i].y;
            source += x1;

            destination = XBIOS_screens[XBIOS_fbnum];
            destination += XBIOS_pitch * rects[i].y;
            destination += x1;

            /* Convert chunky to planar screen */
            SDL_Atari_C2pConvert(source,
                                 destination,
                                 x2 - x1,
                                 rects[i].h,
                                 XBIOS_doubleline,
                                 surface->pitch, XBIOS_pitch);
        }
    }
#ifndef DEBUG_VIDEO_XBIOS
    Setscreen(-1, XBIOS_screens[XBIOS_fbnum], -1);
#endif
    Vsync();

    if ((surface->flags & SDL_DOUBLEBUF) == SDL_DOUBLEBUF) {
        XBIOS_fbnum ^= 1;
        if ((surface->format->BitsPerPixel) > 8) {
            surface->pixels = XBIOS_screens[XBIOS_fbnum];
        }
    }
}

static int
XBIOS_FlipHWSurface(_THIS, SDL_Surface * surface)
{
    if ((surface->format->BitsPerPixel) == 8) {
        void *destscr;
        int destx;

        /* Center on destination screen */
        destscr = XBIOS_screens[XBIOS_fbnum];
        destscr += XBIOS_pitch * ((XBIOS_height - surface->h) >> 1);
        destx = (XBIOS_width - surface->w) >> 1;
        destx &= ~15;
        destscr += destx;

        /* Convert chunky to planar screen */
        SDL_Atari_C2pConvert(surface->pixels,
                             destscr,
                             surface->w,
                             surface->h,
                             XBIOS_doubleline, surface->pitch, XBIOS_pitch);
    }
#ifndef DEBUG_VIDEO_XBIOS
    Setscreen(-1, XBIOS_screens[XBIOS_fbnum], -1);
#endif
    Vsync();

    if ((surface->flags & SDL_DOUBLEBUF) == SDL_DOUBLEBUF) {
        XBIOS_fbnum ^= 1;
        if ((surface->format->BitsPerPixel) > 8) {
            surface->pixels = XBIOS_screens[XBIOS_fbnum];
        }
    }

    return (0);
}

static int
XBIOS_SetColors(_THIS, int firstcolor, int ncolors, SDL_Color * colors)
{
    int i;
    int r, v, b;

    switch (XBIOS_cvdo >> 16) {
    case VDO_ST:
    case VDO_STE:
        for (i = 0; i < ncolors; i++) {
            r = colors[i].r;
            v = colors[i].g;
            b = colors[i].b;

            TT_palette[firstcolor + i] =
                ((r * 30) + (v * 59) + (b * 11)) / 100;
        }
        SDL_Atari_C2pConvert4_pal(TT_palette);  /* convert the lighting */
        break;
    case VDO_TT:
        for (i = 0; i < ncolors; i++) {
            r = colors[i].r;
            v = colors[i].g;
            b = colors[i].b;

            TT_palette[i] = ((r >> 4) << 8) | ((v >> 4) << 4) | (b >> 4);
        }
#ifndef DEBUG_VIDEO_XBIOS
        EsetPalette(firstcolor, ncolors, TT_palette);
#endif
        break;
    case VDO_F30:
        for (i = 0; i < ncolors; i++) {
            r = colors[i].r;
            v = colors[i].g;
            b = colors[i].b;

            F30_palette[i] = (r << 16) | (v << 8) | b;
        }
#ifndef DEBUG_VIDEO_XBIOS
        VsetRGB(firstcolor, ncolors, F30_palette);
#endif
        break;
    }

    return (1);
}
#endif

/* Note:  If we are terminated, this could be called in the middle of
   another SDL video routine -- notably UpdateRects.
*/

#if 0
#if SDL_VIDEO_OPENGL

static void
XBIOS_GL_SwapBuffers(_THIS)
{
    SDL_AtariGL_SwapBuffers(this);
    XBIOS_FlipHWSurface(this, this->screen);
    SDL_AtariGL_MakeCurrent(this);
}

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