extractBookDataByIsbn static method

Future<Book?> extractBookDataByIsbn(String isbn)

Extracts book data by ISBN from libraccio.it This method will automatically construct the URL and handle redirects

Implementation

static Future<Book?> extractBookDataByIsbn(String isbn) async {
  try {
    // Construct the URL with the ISBN
    final url = 'https://www.libraccio.it/libro/$isbn/';
    print('Fetching book data for ISBN: $isbn from URL: $url');

    // Make the request with redirect following
    final client = http.Client();
    try {
      final request = http.Request('GET', Uri.parse(url));
      final response = await client.send(request);

      // Get the final URL after redirects
      final finalUrl = response.request!.url.toString();
      print('Response status code: ${response.statusCode}');
      print('Final URL after redirects: $finalUrl');

      // Get the response body
      final responseBody = await response.stream.bytesToString();
      print('Response body length: ${responseBody.length}');

      if (response.statusCode == 200) {
        print('Successfully fetched page, parsing book data...');
        final book = parseBookFromHtml(responseBody);
        if (book != null) {
          print('Successfully parsed book data: ${book.name}');
        } else {
          print('Failed to parse book data from HTML');
        }
        return book;
      }

      // If we got a redirect page, try to extract the redirect URL and fetch again
      if (responseBody.contains('Object moved') && responseBody.contains('href="')) {
        print('Detected HTML redirect page, extracting redirect URL...');
        final redirectMatch = RegExp(r'href="([^"]+)"').firstMatch(responseBody);
        if (redirectMatch != null) {
          final redirectUrl = redirectMatch.group(1)!;
          final fullRedirectUrl = redirectUrl.startsWith('http') ? redirectUrl : 'https://www.libraccio.it$redirectUrl';
          print('Redirecting to: $fullRedirectUrl');

          final redirectResponse = await http.get(Uri.parse(fullRedirectUrl));
          print('Redirect response status code: ${redirectResponse.statusCode}');
          if (redirectResponse.statusCode == 200) {
            print('Successfully fetched redirected page, parsing book data...');
            final book = parseBookFromHtml(redirectResponse.body);
            if (book != null) {
              print('Successfully parsed book data from redirected page: ${book.name}');
            } else {
              print('Failed to parse book data from redirected HTML');
            }
            return book;
          }
        } else {
          print('Could not extract redirect URL from HTML');
        }
      }

      print('Failed to fetch book data');
      return null;
    } finally {
      client.close();
    }
  } catch (e, stackTrace) {
    // Handle error appropriately in your app
    print('Error fetching book data by ISBN: $e');
    print('Stack trace: $stackTrace');
    return null;
  }
}