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 * in the documentation and/or other materials provided with the
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#ifndef BMPImageDecoder_h
#define BMPImageDecoder_h

#include "platform/image-decoders/bmp/BMPImageReader.h"
#include <memory>

namespace blink {

// This class decodes the BMP image format.
class PLATFORM_EXPORT BMPImageDecoder final : public ImageDecoder {
 public:
  BMPImageDecoder(AlphaOption, ColorSpaceOption, size_t maxDecodedBytes);

  // ImageDecoder:
  String filenameExtension() const override { return "bmp"; }
  void onSetData(SegmentReader*) override;
  // CAUTION: setFailed() deletes |m_reader|.  Be careful to avoid
  // accessing deleted memory, especially when calling this from inside
  // BMPImageReader!
  bool setFailed() override;

 private:
  // ImageDecoder:
  void decodeSize() override { decode(true); }
  void decode(size_t) override { decode(false); }

  // Decodes the image.  If |onlySize| is true, stops decoding after
  // calculating the image size. If decoding fails but there is no more
  // data coming, sets the "decode failure" flag.
  void decode(bool onlySize);

  // Decodes the image.  If |onlySize| is true, stops decoding after
  // calculating the image size. Returns whether decoding succeeded.
  bool decodeHelper(bool onlySize);

  // Processes the file header at the beginning of the data.  Sets
  // |imgDataOffset| based on the header contents. Returns true if the
  // file header could be decoded.
  bool processFileHeader(size_t& imgDataOffset);

  // An index into |m_data| representing how much we've already decoded.
  // Note that this only tracks data _this_ class decodes; once the
  // BMPImageReader takes over this will not be updated further.
  size_t m_decodedOffset;

  // The reader used to do most of the BMP decoding.
  std::unique_ptr<BMPImageReader> m_reader;
};

}  // namespace blink

#endif
