formats/gif/embedder.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_EMBEDDER_H_
#define THIRD_PARTY_CREDENTIO_FORMATS_GIF_EMBEDDER_H_

#include <cstdint>
#include <optional>

#include "absl/status/status.h"
#include "absl/strings/string_view.h"
#include "riegeli/bytes/reader.h"
#include "riegeli/bytes/writer.h"

namespace credentio {
// A utility class to embed a C2PA manifest store as an Application Extension
// block into a GIF file.
class GifEmbedder {
 public:
  // Copies the data from the input to the output and embeds the manifest store.
  // NOTE: Input and output must be disjoint, i.e., in-place embedding is not
  // supported.
  absl::Status CopyAndEmbed(riegeli::Reader& input,
                            absl::string_view manifest_store,
                            int64_t insert_at_offset,
                            std::optional<int64_t> existing_c2pa_length,
                            riegeli::Writer& output) const;
};
}  // namespace credentio

#endif  // THIRD_PARTY_CREDENTIO_FORMATS_GIF_EMBEDDER_H_