// Copyright 2017 Google Inc. All Rights Reserved.

//

// Use of this source code is governed by a BSD-style license

// that can be found in the COPYING file in the root of the source

// tree. An additional intellectual property rights grant can be found

// in the file PATENTS. All contributing project authors may

// be found in the AUTHORS file in the root of the source tree.

// -----------------------------------------------------------------------------

//

//  Simple WebP-to-SDL wrapper. Useful for emscripten.

//

// Author: James Zern (jzern@google.com)

#ifdef HAVE_CONFIG_H

#include "src/webp/config.h"

#endif

#if defined(WEBP_HAVE_SDL)

#include "webp_to_sdl.h"

#include <stdio.h>

#include "src/webp/decode.h"

#if defined(WEBP_HAVE_JUST_SDL_H)

#include <SDL.h>

#else

#include <SDL/SDL.h>

#endif

static int init_ok = 0;

int WebpToSDL(const char* data, unsigned int data_size) {

  int ok = 0;

  VP8StatusCode status;

  WebPDecoderConfig config;

  WebPBitstreamFeatures* const input = &config.input;

  WebPDecBuffer* const output = &config.output;

  SDL_Surface* screen = NULL;

  SDL_Surface* surface = NULL;

  if (!WebPInitDecoderConfig(&config)) {

    fprintf(stderr, "Library version mismatch!\n");

    return 1;

  }

  if (!init_ok) {

    SDL_Init(SDL_INIT_VIDEO);

    init_ok = 1;

  }

  status = WebPGetFeatures((uint8_t*)data, (size_t)data_size, &config.input);

  if (status != VP8_STATUS_OK) goto Error;

  screen = SDL_SetVideoMode(input->width, input->height, 32, SDL_SWSURFACE);

  if (screen == NULL) {

    fprintf(stderr, "Unable to set video mode (32bpp %dx%d)!\n",

            input->width, input->height);

    goto Error;

  }

  surface = SDL_CreateRGBSurface(SDL_SWSURFACE,

                                 input->width, input->height, 32,

                                 0x000000ffu,   // R mask

                                 0x0000ff00u,   // G mask

                                 0x00ff0000u,   // B mask

                                 0xff000000u);  // A mask

  if (surface == NULL) {

    fprintf(stderr, "Unable to create %dx%d RGBA surface!\n",

            input->width, input->height);

    goto Error;

  }

  if (SDL_MUSTLOCK(surface)) SDL_LockSurface(surface);

#if SDL_BYTEORDER == SDL_BIG_ENDIAN

  output->colorspace = MODE_BGRA;

#else

  output->colorspace = MODE_RGBA;

#endif

  output->width  = surface->w;

  output->height = surface->h;

  output->u.RGBA.rgba   = surface->pixels;

  output->u.RGBA.stride = surface->pitch;

  output->u.RGBA.size   = surface->pitch * surface->h;

  output->is_external_memory = 1;

  status = WebPDecode((const uint8_t*)data, (size_t)data_size, &config);

  if (status != VP8_STATUS_OK) {

    fprintf(stderr, "Error decoding image (%d)\n", status);

    goto Error;

  }

  if (SDL_MUSTLOCK(surface)) SDL_UnlockSurface(surface);

  if (SDL_BlitSurface(surface, NULL, screen, NULL) ||

      SDL_Flip(screen)) {

    goto Error;

  }

  ok = 1;

 Error:

  SDL_FreeSurface(surface);

  SDL_FreeSurface(screen);

  WebPFreeDecBuffer(output);

  return ok;

}

//------------------------------------------------------------------------------

#endif  // WEBP_HAVE_SDL