// Copyright 2015 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.

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

//

//  Additional WebP utilities.

//

#include "extras/extras.h"

#include "webp/format_constants.h"

#include <assert.h>

#include <string.h>

#define XTRA_MAJ_VERSION 1

#define XTRA_MIN_VERSION 0

#define XTRA_REV_VERSION 0

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

int WebPGetExtrasVersion(void) {

  return (XTRA_MAJ_VERSION << 16) | (XTRA_MIN_VERSION << 8) | XTRA_REV_VERSION;

}

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

int WebPImportGray(const uint8_t* gray_data, WebPPicture* pic) {

  int y, width, uv_width;

  if (pic == NULL || gray_data == NULL) return 0;

  pic->colorspace = WEBP_YUV420;

  if (!WebPPictureAlloc(pic)) return 0;

  width = pic->width;

  uv_width = (width + 1) >> 1;

  for (y = 0; y < pic->height; ++y) {

    memcpy(pic->y + y * pic->y_stride, gray_data, width);

    gray_data += width;    // <- we could use some 'data_stride' here if needed

    if ((y & 1) == 0) {

      memset(pic->u + (y >> 1) * pic->uv_stride, 128, uv_width);

      memset(pic->v + (y >> 1) * pic->uv_stride, 128, uv_width);

    }

  }

  return 1;

}

int WebPImportRGB565(const uint8_t* rgb565, WebPPicture* pic) {

  int x, y;

  uint32_t* dst;

  if (pic == NULL || rgb565 == NULL) return 0;

  pic->colorspace = WEBP_YUV420;

  pic->use_argb = 1;

  if (!WebPPictureAlloc(pic)) return 0;

  dst = pic->argb;

  for (y = 0; y < pic->height; ++y) {

    const int width = pic->width;

    for (x = 0; x < width; ++x) {

#ifdef WEBP_SWAP_16BIT_CSP

      const uint32_t rg = rgb565[2 * x + 1];

      const uint32_t gb = rgb565[2 * x + 0];

#else

      const uint32_t rg = rgb565[2 * x + 0];

      const uint32_t gb = rgb565[2 * x + 1];

#endif

      uint32_t r = rg & 0xf8;

      uint32_t g = ((rg << 5) | (gb >> 3)) & 0xfc;

      uint32_t b = (gb << 5);

      // dithering

      r = r | (r >> 5);

      g = g | (g >> 6);

      b = b | (b >> 5);

      dst[x] = (0xffu << 24) | (r << 16) | (g << 8) | b;

    }

    rgb565 += 2 * width;

    dst += pic->argb_stride;

  }

  return 1;

}

int WebPImportRGB4444(const uint8_t* rgb4444, WebPPicture* pic) {

  int x, y;

  uint32_t* dst;

  if (pic == NULL || rgb4444 == NULL) return 0;

  pic->colorspace = WEBP_YUV420;

  pic->use_argb = 1;

  if (!WebPPictureAlloc(pic)) return 0;

  dst = pic->argb;

  for (y = 0; y < pic->height; ++y) {

    const int width = pic->width;

    for (x = 0; x < width; ++x) {

#ifdef WEBP_SWAP_16BIT_CSP

      const uint32_t rg = rgb4444[2 * x + 1];

      const uint32_t ba = rgb4444[2 * x + 0];

#else

      const uint32_t rg = rgb4444[2 * x + 0];

      const uint32_t ba = rgb4444[2 * x + 1];

#endif

      uint32_t r = rg & 0xf0;

      uint32_t g = (rg << 4);

      uint32_t b = (ba & 0xf0);

      uint32_t a = (ba << 4);

      // dithering

      r = r | (r >> 4);

      g = g | (g >> 4);

      b = b | (b >> 4);

      a = a | (a >> 4);

      dst[x] = (a << 24) | (r << 16) | (g << 8) | b;

    }

    rgb4444 += 2 * width;

    dst += pic->argb_stride;

  }

  return 1;

}

int WebPImportColorMappedARGB(const uint8_t* indexed, int indexed_stride,

                              const uint32_t palette[], int palette_size,

                              WebPPicture* pic) {

  int x, y;

  uint32_t* dst;

  // 256 as the input buffer is uint8_t.

  assert(MAX_PALETTE_SIZE <= 256);

  if (pic == NULL || indexed == NULL || indexed_stride < pic->width ||

      palette == NULL || palette_size > MAX_PALETTE_SIZE || palette_size <= 0) {

    return 0;

  }

  pic->use_argb = 1;

  if (!WebPPictureAlloc(pic)) return 0;

  dst = pic->argb;

  for (y = 0; y < pic->height; ++y) {

    for (x = 0; x < pic->width; ++x) {

      // Make sure we are within the palette.

      if (indexed[x] >= palette_size) {

        WebPPictureFree(pic);

        return 0;

      }

      dst[x] = palette[indexed[x]];

    }

    indexed += indexed_stride;

    dst += pic->argb_stride;

  }

  return 1;

}

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