formats/gif/reader.h

// Copyright 2026 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//    https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//

#ifndef THIRD_PARTY_CREDENTIO_FORMATS_GIF_READER_H_
#define THIRD_PARTY_CREDENTIO_FORMATS_GIF_READER_H_

#include <cstdint>
#include <string>

#include "absl/functional/function_ref.h"
#include "absl/status/status.h"
#include "absl/status/statusor.h"
#include "riegeli/bytes/reader.h"

namespace credentio {

// GIF Reader for C2PA, holds onto a reference to a riegeli::Reader which
// must outlive the reader.
struct GifBlock {
  uint64_t offset;
  uint64_t length;
  std::string type;

  bool operator==(const GifBlock& other) const {
    return offset == other.offset && length == other.length &&
           type == other.type;
  }
};

using GifBlockProcessor =
    absl::FunctionRef<absl::StatusOr<bool>(const GifBlock&)>;

absl::Status IterateOverGifBlocks(riegeli::Reader& input,
                                  GifBlockProcessor processor,
                                  int64_t end_offset = -1);

}  // namespace credentio

#endif  // THIRD_PARTY_CREDENTIO_FORMATS_GIF_READER_H_