getFiles method

Future<List<WalrusFile>> getFiles({ required List<String> ids, })

Get WalrusFile instances for a list of blob IDs or quilt patch IDs.

Each ID can be either:

• A 32-byte blob ID (URL-safe base64) → returned as a plain file
• A 37-byte quilt patch ID → returned as the specific file within the quilt

Blob readers are shared for the same blob ID to avoid redundant network calls.

Mirrors the TS SDK's getFiles().

Implementation

Future<List<WalrusFile>> getFiles({required List<String> ids}) async {
  final state = await _stateReader.systemState();
  final numShards = state.nShards;

  // Dedup blob readers.
  final readersByBlobId = <String, BlobReader>{};
  final quiltReadersByBlobId = <String, QuiltReader>{};
  final parsedIds = ids.map(parseWalrusId).toList();

  for (final id in parsedIds) {
    final blobId = id.kind == 'blob' ? id.blobId! : id.patchId!.quiltId;
    readersByBlobId.putIfAbsent(
      blobId,
      () => BlobReader(
        blobId: blobId,
        numShards: numShards,
        readBlob: (id) => readBlob(blobId: id),
        readSecondarySliver: (id, index) =>
            getSecondarySliver(blobId: id, sliverIndex: index),
      ),
    );

    if (id.kind == 'quiltPatch') {
      quiltReadersByBlobId.putIfAbsent(
        blobId,
        () => QuiltReader(blob: readersByBlobId[blobId]!),
      );
    }
  }

  return parsedIds.map((id) {
    if (id.kind == 'blob') {
      return WalrusFile(reader: readersByBlobId[id.blobId!]!);
    }

    final patchId = id.patchId!;
    return WalrusFile(
      reader: QuiltFileReader(
        quilt: quiltReadersByBlobId[patchId.quiltId]!,
        sliverIndex: patchId.startIndex,
      ),
    );
  }).toList();
}