/*

    SDL - Simple DirectMedia Layer

    Copyright (C) 1997-2011 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"

#include "SDL_video.h"

#include "SDL_compat.h"

#include "SDL_sysvideo.h"

#include "SDL_blit.h"

#include "SDL_RLEaccel_c.h"

#include "SDL_pixels_c.h"

/* Public routines */

/*

 * Create an empty RGB surface of the appropriate depth

 */

SDL_Surface *

SDL_CreateRGBSurface(Uint32 flags,

                     int width, int height, int depth,

                     Uint32 Rmask, Uint32 Gmask, Uint32 Bmask, Uint32 Amask)

{

    SDL_Surface *surface;

    Uint32 format;

    /* The flags are no longer used, make the compiler happy */

    (void)flags;

    /* Get the pixel format */

    format = SDL_MasksToPixelFormatEnum(depth, Rmask, Gmask, Bmask, Amask);

    if (format == SDL_PIXELFORMAT_UNKNOWN) {

        SDL_SetError("Unknown pixel format");

        return NULL;

    }

    /* Allocate the surface */

    surface = (SDL_Surface *) SDL_calloc(1, sizeof(*surface));

    if (surface == NULL) {

        SDL_OutOfMemory();

        return NULL;

    }

    surface->format = SDL_AllocFormat(format);

    if (!surface->format) {

        SDL_FreeSurface(surface);

        return NULL;

    }

    surface->w = width;

    surface->h = height;

    surface->pitch = SDL_CalculatePitch(surface);

    SDL_SetClipRect(surface, NULL);

    if (SDL_ISPIXELFORMAT_INDEXED(surface->format->format)) {

        SDL_Palette *palette =

            SDL_AllocPalette((1 << surface->format->BitsPerPixel));

        if (!palette) {

            SDL_FreeSurface(surface);

            return NULL;

        }

            /* Create a black and white bitmap palette */

            palette->colors[0].r = 0xFF;

            palette->colors[0].g = 0xFF;

            palette->colors[0].b = 0xFF;

            palette->colors[1].r = 0x00;

            palette->colors[1].g = 0x00;

            palette->colors[1].b = 0x00;

        }

        SDL_SetSurfacePalette(surface, palette);

        SDL_FreePalette(palette);

    }

    /* Get the pixels */

    if (surface->w && surface->h) {

        surface->pixels = SDL_malloc(surface->h * surface->pitch);

        if (!surface->pixels) {

            SDL_FreeSurface(surface);

            SDL_OutOfMemory();

            return NULL;

        }

        /* This is important for bitmaps */

        SDL_memset(surface->pixels, 0, surface->h * surface->pitch);

    }

    /* Allocate an empty mapping */

    surface->map = SDL_AllocBlitMap();

    if (!surface->map) {

        SDL_FreeSurface(surface);

        return NULL;

    }

    /* By default surface with an alpha mask are set up for blending */

    if (Amask) {

        SDL_SetSurfaceBlendMode(surface, SDL_BLENDMODE_BLEND);

    }

    /* The surface is ready to go */

    surface->refcount = 1;

    return surface;

}

/*

 * Create an RGB surface from an existing memory buffer

 */

SDL_Surface *

SDL_CreateRGBSurfaceFrom(void *pixels,

                         int width, int height, int depth, int pitch,

                         Uint32 Rmask, Uint32 Gmask, Uint32 Bmask,

                         Uint32 Amask)

{

    SDL_Surface *surface;

    surface =

        SDL_CreateRGBSurface(0, 0, 0, depth, Rmask, Gmask, Bmask, Amask);

    if (surface != NULL) {

        surface->flags |= SDL_PREALLOC;

        surface->pixels = pixels;

        surface->w = width;

        surface->h = height;

        surface->pitch = pitch;

        SDL_SetClipRect(surface, NULL);

    }

    return surface;

}

int

SDL_SetSurfacePalette(SDL_Surface * surface, SDL_Palette * palette)

{

    if (!surface) {

        SDL_SetError("SDL_SetSurfacePalette() passed a NULL surface");

        return -1;

    }

    return SDL_SetPixelFormatPalette(surface->format, palette);

}

int

SDL_SetSurfaceRLE(SDL_Surface * surface, int flag)

{

    int flags;

    if (!surface) {

        return -1;

    }

    flags = surface->map->info.flags;

    if (flag) {

        surface->map->info.flags |= SDL_COPY_RLE_DESIRED;

    } else {

        surface->map->info.flags &= ~SDL_COPY_RLE_DESIRED;

    }

    if (surface->map->info.flags != flags) {

        SDL_InvalidateMap(surface->map);

    }

    return 0;

}

int

SDL_SetColorKey(SDL_Surface * surface, int flag, Uint32 key)

{

    int flags;

    if (!surface) {

        return -1;

    }

    if (flag & SDL_RLEACCEL) {

        SDL_SetSurfaceRLE(surface, 1);

    }

    flags = surface->map->info.flags;

    if (flag) {

        surface->map->info.flags |= SDL_COPY_COLORKEY;

        surface->map->info.colorkey = key;

    } else {

        surface->map->info.flags &= ~SDL_COPY_COLORKEY;

    }

    if (surface->map->info.flags != flags) {

        SDL_InvalidateMap(surface->map);

    }

    /* Compatibility mode */

    if (surface->map->info.flags & SDL_COPY_COLORKEY) {

        surface->flags |= SDL_SRCCOLORKEY;

    } else {

        surface->flags &= ~SDL_SRCCOLORKEY;

    }

    return 0;

}

int

SDL_GetColorKey(SDL_Surface * surface, Uint32 * key)

{

    if (!surface) {

        return -1;

    }

    if (!(surface->map->info.flags & SDL_COPY_COLORKEY)) {

        return -1;

    }

    if (key) {

        *key = surface->map->info.colorkey;

    }

    return 0;

}

/* This is a fairly slow function to switch from colorkey to alpha */

static void

SDL_ConvertColorkeyToAlpha(SDL_Surface * surface)

{

    int x, y;

    if (!surface) {

        return;

    }

    if (!(surface->map->info.flags & SDL_COPY_COLORKEY) ||

        !surface->format->Amask) {

        return;

    }

    SDL_LockSurface(surface);

    switch (surface->format->BytesPerPixel) {

    case 2:

        {

            Uint16 *row, *spot;

            Uint16 ckey = (Uint16) surface->map->info.colorkey;

            Uint16 mask = (Uint16) (~surface->format->Amask);

            row = (Uint16 *) surface->pixels;

            for (y = surface->h; y--;) {

                spot = row;

                for (x = surface->w; x--;) {

                    if (*spot == ckey) {

                        *spot &= mask;

                    }

                    ++spot;

                }

                row += surface->pitch / 2;

            }

        }

        break;

    case 3:

        /* FIXME */

        break;

    case 4:

        {

            Uint32 *row, *spot;

            Uint32 ckey = surface->map->info.colorkey;

            Uint32 mask = ~surface->format->Amask;

            row = (Uint32 *) surface->pixels;

            for (y = surface->h; y--;) {

                spot = row;

                for (x = surface->w; x--;) {

                    if (*spot == ckey) {

                        *spot &= mask;

                    }

                    ++spot;

                }

                row += surface->pitch / 4;

            }

        }

        break;

    }

    SDL_UnlockSurface(surface);

    SDL_SetColorKey(surface, 0, 0);

    SDL_SetSurfaceBlendMode(surface, SDL_BLENDMODE_BLEND);

}

int

SDL_SetSurfaceColorMod(SDL_Surface * surface, Uint8 r, Uint8 g, Uint8 b)

{

    int flags;

    if (!surface) {

        return -1;

    }

    surface->map->info.r = r;

    surface->map->info.g = g;

    surface->map->info.b = b;

    flags = surface->map->info.flags;

    if (r != 0xFF || g != 0xFF || b != 0xFF) {

        surface->map->info.flags |= SDL_COPY_MODULATE_COLOR;

    } else {

        surface->map->info.flags &= ~SDL_COPY_MODULATE_COLOR;

    }

    if (surface->map->info.flags != flags) {

        SDL_InvalidateMap(surface->map);

    }

    return 0;

}

int

SDL_GetSurfaceColorMod(SDL_Surface * surface, Uint8 * r, Uint8 * g, Uint8 * b)

{

    if (!surface) {

        return -1;

    }

    if (r) {

        *r = surface->map->info.r;

    }

    if (g) {

        *g = surface->map->info.g;

    }

    if (b) {

        *b = surface->map->info.b;

    }

    return 0;

}

int

SDL_SetSurfaceAlphaMod(SDL_Surface * surface, Uint8 alpha)

{

    int flags;

    if (!surface) {

        return -1;

    }

    surface->map->info.a = alpha;

    flags = surface->map->info.flags;

    if (alpha != 0xFF) {

        surface->map->info.flags |= SDL_COPY_MODULATE_ALPHA;

    } else {

        surface->map->info.flags &= ~SDL_COPY_MODULATE_ALPHA;

    }

    if (surface->map->info.flags != flags) {

        SDL_InvalidateMap(surface->map);

    }

    return 0;

}

int

SDL_GetSurfaceAlphaMod(SDL_Surface * surface, Uint8 * alpha)

{

    if (!surface) {

        return -1;

    }

    if (alpha) {

        *alpha = surface->map->info.a;

    }

    return 0;

}

int

SDL_SetSurfaceBlendMode(SDL_Surface * surface, SDL_BlendMode blendMode)

{

    int flags, status;

    if (!surface) {

        return -1;

    }

    status = 0;

    flags = surface->map->info.flags;

    surface->map->info.flags &=

        ~(SDL_COPY_BLEND | SDL_COPY_ADD | SDL_COPY_MOD);

    switch (blendMode) {

    case SDL_BLENDMODE_NONE:

        break;

    case SDL_BLENDMODE_BLEND:

        surface->map->info.flags |= SDL_COPY_BLEND;

        break;

    case SDL_BLENDMODE_ADD:

        surface->map->info.flags |= SDL_COPY_ADD;

        break;

    case SDL_BLENDMODE_MOD:

        surface->map->info.flags |= SDL_COPY_MOD;

        break;

    default:

        SDL_Unsupported();

        status = -1;

        break;

    }

    if (surface->map->info.flags != flags) {

        SDL_InvalidateMap(surface->map);

    }

    /* Compatibility mode */

    if (surface->map->info.flags & SDL_COPY_BLEND) {

        surface->flags |= SDL_SRCALPHA;

    } else {

        surface->flags &= ~SDL_SRCALPHA;

    }

    return status;

}

int

SDL_GetSurfaceBlendMode(SDL_Surface * surface, SDL_BlendMode *blendMode)

{

    if (!surface) {

        return -1;

    }

    if (!blendMode) {

        return 0;

    }

    switch (surface->map->

            info.flags & (SDL_COPY_BLEND | SDL_COPY_ADD | SDL_COPY_MOD)) {

    case SDL_COPY_BLEND:

        *blendMode = SDL_BLENDMODE_BLEND;

        break;

    case SDL_COPY_ADD:

        *blendMode = SDL_BLENDMODE_ADD;

        break;

    case SDL_COPY_MOD:

        *blendMode = SDL_BLENDMODE_MOD;

        break;

    default:

        *blendMode = SDL_BLENDMODE_NONE;

        break;

    }

    return 0;

}

SDL_bool

SDL_SetClipRect(SDL_Surface * surface, const SDL_Rect * rect)

{

    SDL_Rect full_rect;

    /* Don't do anything if there's no surface to act on */

    if (!surface) {

        return SDL_FALSE;

    }

    /* Set up the full surface rectangle */

    full_rect.x = 0;

    full_rect.y = 0;

    full_rect.w = surface->w;

    full_rect.h = surface->h;

    /* Set the clipping rectangle */

    if (!rect) {

        surface->clip_rect = full_rect;

        return SDL_TRUE;

    }

    return SDL_IntersectRect(rect, &full_rect, &surface->clip_rect);

}

void

SDL_GetClipRect(SDL_Surface * surface, SDL_Rect * rect)

{

    if (surface && rect) {

        *rect = surface->clip_rect;

    }

}

/* 

 * Set up a blit between two surfaces -- split into three parts:

 * The upper part, SDL_UpperBlit(), performs clipping and rectangle 

 * verification.  The lower part is a pointer to a low level

 * accelerated blitting function.

 *

 * These parts are separated out and each used internally by this 

 * library in the optimimum places.  They are exported so that if