fetchWithAuth method

Implementation

Future<FetchResponse> fetchWithAuth(
  String url,
  String authToken, {
  required void Function(double progress) onProgress,
}) async {
  try {
    // Create fetch options with auth header
    final options = _createFetchOptions(authToken);

    // Fetch with auth
    final response = await _fetch(url, options);

    // Check response status
    if (!response.isOk) {
      final statusCode = response.statusCode;
      final statusText = response.statusMessage;

      if (statusCode == 401) {
        throw JsInteropException(
          'Authentication failed: Invalid or expired token',
          statusCode: 401,
        );
      } else if (statusCode == 403) {
        throw JsInteropException(
          'Access denied: Token lacks required permissions',
          statusCode: 403,
        );
      } else if (statusCode == 404) {
        throw JsInteropException(
          'Model not found: Check URL is correct',
          statusCode: 404,
        );
      } else {
        throw JsInteropException(
          'HTTP error: $statusText',
          statusCode: statusCode,
        );
      }
    }

    // Stream response body with progress
    final chunks = await _streamResponseBody(
      response,
      _getContentLength(response),
      onProgress,
    );

    // Concatenate chunks
    final totalLength = chunks.fold<int>(0, (sum, chunk) => sum + chunk.length);
    final data = Uint8List(totalLength);
    int offset = 0;
    for (final chunk in chunks) {
      data.setRange(offset, offset + chunk.length, chunk);
      offset += chunk.length;
    }

    return FetchResponse(data, response.statusCode);
  } catch (e) {
    if (e is JsInteropException) rethrow;
    throw JsInteropException('Failed to fetch authenticated file: $e');
  }
}