// Copyright 2014 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.

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

//

// WebP decode.

#ifdef HAVE_CONFIG_H

#include "webp/config.h"

#endif

#include <assert.h>

#include <stdio.h>

#include <stdlib.h>

#include "../examples/unicode.h"

#include "./imageio_util.h"

#include "./metadata.h"

#include "./webpdec.h"

#include "webp/decode.h"

#include "webp/demux.h"

#include "webp/encode.h"

#include "webp/mux_types.h"

#include "webp/types.h"

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

// WebP decoding

static const char* const kStatusMessages[VP8_STATUS_NOT_ENOUGH_DATA + 1] = {

    "OK",

    "OUT_OF_MEMORY",

    "INVALID_PARAM",

    "BITSTREAM_ERROR",

    "UNSUPPORTED_FEATURE",

    "SUSPENDED",

    "USER_ABORT",

    "NOT_ENOUGH_DATA"};

static void PrintAnimationWarning(const WebPDecoderConfig* const config) {

  if (config->input.has_animation) {

    fprintf(stderr,

            "Error! Decoding of an animated WebP file is not supported.\n"

            "       Use webpmux to extract the individual frames or\n"

            "       vwebp to view this image.\n");

  }

}

void PrintWebPError(const char* const in_file, int status) {

  WFPRINTF(stderr, "Decoding of %s failed.\n", (const W_CHAR*)in_file);

  fprintf(stderr, "Status: %d", status);

  if (status >= VP8_STATUS_OK && status <= VP8_STATUS_NOT_ENOUGH_DATA) {

    fprintf(stderr, "(%s)", kStatusMessages[status]);

  }

  fprintf(stderr, "\n");

}

int LoadWebP(const char* const in_file, const uint8_t** data, size_t* data_size,

             WebPBitstreamFeatures* bitstream) {

  VP8StatusCode status;

  WebPBitstreamFeatures local_features;

  if (!ImgIoUtilReadFile(in_file, data, data_size)) return 0;

  if (bitstream == NULL) {

    bitstream = &local_features;

  }

  status = WebPGetFeatures(*data, *data_size, bitstream);

  if (status != VP8_STATUS_OK) {

    WebPFree((void*)*data);

    *data = NULL;

    *data_size = 0;

    PrintWebPError(in_file, status);

    return 0;

  }

  return 1;

}

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

VP8StatusCode DecodeWebP(const uint8_t* const data, size_t data_size,

                         WebPDecoderConfig* const config) {

  if (config == NULL) return VP8_STATUS_INVALID_PARAM;

  PrintAnimationWarning(config);

  return WebPDecode(data, data_size, config);

}

VP8StatusCode DecodeWebPIncremental(const uint8_t* const data, size_t data_size,

                                    WebPDecoderConfig* const config) {

  VP8StatusCode status = VP8_STATUS_OK;

  if (config == NULL) return VP8_STATUS_INVALID_PARAM;

  PrintAnimationWarning(config);

  // Decoding call.

  {

    WebPIDecoder* const idec = WebPIDecode(data, data_size, config);

    if (idec == NULL) {

      fprintf(stderr, "Failed during WebPIDecode().\n");

      return VP8_STATUS_OUT_OF_MEMORY;

    } else {

      status = WebPIUpdate(idec, data, data_size);

      WebPIDelete(idec);

    }

  }

  return status;

}

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

// Metadata

static int ExtractMetadata(const uint8_t* const data, size_t data_size,

                           Metadata* const metadata) {

  WebPData webp_data = {data, data_size};

  WebPDemuxer* const demux = WebPDemux(&webp_data);

  WebPChunkIterator chunk_iter;

  uint32_t flags;

  if (demux == NULL) return 0;

  assert(metadata != NULL);

  flags = WebPDemuxGetI(demux, WEBP_FF_FORMAT_FLAGS);

  if ((flags & ICCP_FLAG) && WebPDemuxGetChunk(demux, "ICCP", 1, &chunk_iter)) {

    MetadataCopy((const char*)chunk_iter.chunk.bytes, chunk_iter.chunk.size,

                 &metadata->iccp);

    WebPDemuxReleaseChunkIterator(&chunk_iter);

  }

  if ((flags & EXIF_FLAG) && WebPDemuxGetChunk(demux, "EXIF", 1, &chunk_iter)) {

    MetadataCopy((const char*)chunk_iter.chunk.bytes, chunk_iter.chunk.size,

                 &metadata->exif);

    WebPDemuxReleaseChunkIterator(&chunk_iter);

  }

  if ((flags & XMP_FLAG) && WebPDemuxGetChunk(demux, "XMP ", 1, &chunk_iter)) {

    MetadataCopy((const char*)chunk_iter.chunk.bytes, chunk_iter.chunk.size,

                 &metadata->xmp);

    WebPDemuxReleaseChunkIterator(&chunk_iter);

  }

  WebPDemuxDelete(demux);

  return 1;

}

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

int ReadWebP(const uint8_t* const data, size_t data_size,

             WebPPicture* const pic, int keep_alpha, Metadata* const metadata) {

  int ok = 0;

  VP8StatusCode status = VP8_STATUS_OK;

  WebPDecoderConfig config;

  WebPDecBuffer* const output_buffer = &config.output;

  WebPBitstreamFeatures* const bitstream = &config.input;

  if (data == NULL || data_size == 0 || pic == NULL) return 0;

  if (!WebPInitDecoderConfig(&config)) {

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

    return 0;

  }

  status = WebPGetFeatures(data, data_size, bitstream);

  if (status != VP8_STATUS_OK) {

    PrintWebPError("input data", status);

    return 0;

  }

  do {

    const int has_alpha = keep_alpha && bitstream->has_alpha;

    uint64_t stride;

    pic->width = bitstream->width;

    pic->height = bitstream->height;

    if (pic->use_argb) {

      stride = (uint64_t)bitstream->width * 4;

    } else {

      stride = (uint64_t)bitstream->width * (has_alpha ? 5 : 3) / 2;

      pic->colorspace = has_alpha ? WEBP_YUV420A : WEBP_YUV420;

    }

    if (!ImgIoUtilCheckSizeArgumentsOverflow(stride, bitstream->height)) {

      status = VP8_STATUS_OUT_OF_MEMORY;

      break;

    }

    ok = WebPPictureAlloc(pic);

    if (!ok) {

      status = VP8_STATUS_OUT_OF_MEMORY;

      break;

    }

    if (pic->use_argb) {

#ifdef WORDS_BIGENDIAN

      output_buffer->colorspace = MODE_ARGB;

#else

      output_buffer->colorspace = MODE_BGRA;

#endif

      output_buffer->u.RGBA.rgba = (uint8_t*)pic->argb;

      output_buffer->u.RGBA.stride = pic->argb_stride * sizeof(uint32_t);

      output_buffer->u.RGBA.size = output_buffer->u.RGBA.stride * pic->height;

    } else {

      output_buffer->colorspace = has_alpha ? MODE_YUVA : MODE_YUV;

      output_buffer->u.YUVA.y = pic->y;

      output_buffer->u.YUVA.u = pic->u;

      output_buffer->u.YUVA.v = pic->v;

      output_buffer->u.YUVA.a = has_alpha ? pic->a : NULL;

      output_buffer->u.YUVA.y_stride = pic->y_stride;

      output_buffer->u.YUVA.u_stride = pic->uv_stride;

      output_buffer->u.YUVA.v_stride = pic->uv_stride;

      output_buffer->u.YUVA.a_stride = has_alpha ? pic->a_stride : 0;

      output_buffer->u.YUVA.y_size = pic->height * pic->y_stride;

      output_buffer->u.YUVA.u_size = (pic->height + 1) / 2 * pic->uv_stride;

      output_buffer->u.YUVA.v_size = (pic->height + 1) / 2 * pic->uv_stride;

      output_buffer->u.YUVA.a_size = pic->height * pic->a_stride;

    }

    output_buffer->is_external_memory = 1;

    status = DecodeWebP(data, data_size, &config);

    ok = (status == VP8_STATUS_OK);

    if (ok && !keep_alpha && pic->use_argb) {

      // Need to wipe out the alpha value, as requested.

      int x, y;

      uint32_t* argb = pic->argb;

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

        for (x = 0; x < pic->width; ++x) argb[x] |= 0xff000000u;

        argb += pic->argb_stride;

      }

    }

  } while (0);  // <- so we can 'break' out of the loop

  if (status != VP8_STATUS_OK) {

    PrintWebPError("input data", status);

    ok = 0;

  }

  WebPFreeDecBuffer(output_buffer);

  if (ok && metadata != NULL) {

    ok = ExtractMetadata(data, data_size, metadata);

    if (!ok) {

      PrintWebPError("metadata", VP8_STATUS_BITSTREAM_ERROR);

    }

  }

  if (!ok) WebPPictureFree(pic);

  return ok;

}

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