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 * Copyright (C) 2020 Apple Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions
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#ifndef THIRD_PARTY_BLINK_RENDERER_PLATFORM_WTF_TEXT_TEXT_CODEC_CJK_H_
#define THIRD_PARTY_BLINK_RENDERER_PLATFORM_WTF_TEXT_TEXT_CODEC_CJK_H_

#include <optional>

#include "third_party/blink/renderer/platform/wtf/functional.h"
#include "third_party/blink/renderer/platform/wtf/text/code_point_iterator.h"
#include "third_party/blink/renderer/platform/wtf/text/string_builder.h"
#include "third_party/blink/renderer/platform/wtf/text/text_codec.h"
#include "third_party/blink/renderer/platform/wtf/text/wtf_string.h"
#include "third_party/blink/renderer/platform/wtf/wtf_export.h"

namespace blink {

// TextCodecCjk supports following encodings:
// * Japanese characters (EUC-JP, ISO-2022-JP, ShiftJIS)
// * Korean characters (EUC-KR)
// * Simplified Chinese characters (GB18030, GBK)
// * Traditional Chinese characters (Big5)
//
// ICU4C behaves much different from the WHATWG specification
// (https://encoding.spec.whatwg.org/). It was difficult to fulfill the
// specification by using TextCodecICU.
class TextCodecCjk final : public TextCodec {
 public:
  class Decoder;
  static void RegisterEncodingNames(EncodingNameRegistrar);
  static void RegisterCodecs(TextCodecRegistrar);
  // Returns true if the given `name` is supported.
  WTF_EXPORT static bool IsSupported(StringView name);

 private:
  enum class Encoding : uint8_t;
  explicit TextCodecCjk(Encoding);
  WTF_EXPORT static std::unique_ptr<TextCodec> Create(const TextEncoding&);
  String Decode(base::span<const uint8_t> data,
                FlushBehavior,
                bool stop_on_error,
                bool& saw_error) override;
  std::string Encode(base::span<const UChar>, UnencodableHandling) override;
  std::string Encode(base::span<const LChar>, UnencodableHandling) override;

  Vector<uint8_t> EncodeCommon(StringView string, UnencodableHandling) const;

  const Encoding encoding_;
  std::unique_ptr<Decoder> decoder_;
};

}  // namespace blink

#endif  // THIRD_PARTY_BLINK_RENDERER_PLATFORM_WTF_TEXT_TEXT_CODEC_CJK_H_