import 'dart:typed_data';
import 'dart:io';
import 'package:path_provider/path_provider.dart';
import '../core/failure.dart';

Future<Uint8List> readBounded(Stream<List<int>> stream, int limit) async {
  final bytes = BytesBuilder(copy: false);
  await for (final chunk in stream) {
    if (bytes.length + chunk.length > limit) {
      throw const Failure('invalidImport');
    }
    bytes.add(chunk);
  }
  return bytes.takeBytes();
}

Future<void> purgeTransferCache() async {
  final root = await getTemporaryDirectory();
  await for (final entry in root.list(followLinks: false)) {
    if (entry is Directory &&
        entry.path
            .split(Platform.pathSeparator)
            .last
            .startsWith('sm-transfer-')) {
      try {
        await entry.delete(recursive: true);
      } catch (_) {
        /* Retry at next launch. */
      }
    }
  }
}