bin/simple_browser/lib/src/utils/tlds_provider.dart

// Copyright 2019 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import 'dart:async';
import 'package:fuchsia_logger/logger.dart';
import 'package:http/http.dart' as http;

class TldsProvider {
  String? _data;

  // Creates the TldsModel Once when the simple browser is initiated.
  Future<String?> loadIanaTldsList() async {
    try {
      final response = await http
          .get(Uri.parse('http://data.iana.org/TLD/tlds-alpha-by-domain.txt'));

      if (response.statusCode == 200) {
        log.info('Successfully loaded a TLD list from iana.org');
        return response.body;
      } else {
        log.warning('Failed to load a TLD list from iana.org '
            '(Bad response: ${response.statusCode})');
        return null;
      }
      // ignore: avoid_catches_without_on_clauses
    } catch (e) {
      log.severe('Failed to load a TLD list from iana.org ($e)');
      return null;
    }
  }

  Future<List<String>?> fetchTldsList() async {
    String? data;

    data = _data ?? await loadIanaTldsList();

    if (data == null) {
      return null;
    }

    List<String> tldsList = data.split('\n');

    // Removes all white spaces.
    for (int i = 0; i < tldsList.length; i++) {
      tldsList[i] = tldsList[i].replaceAll(RegExp(r'\s+'), '');
    }

    // Removes all comments and empty elements.
    tldsList.removeWhere((item) => item.isEmpty || item.startsWith('#'));

    return tldsList;
  }

  set data(String testData) => _data = testData;
}