source_provider.dart

// Defines App sources and provides functions used to interact with them
// AppSource is an abstract class with a concrete implementation for each source

import 'dart:convert';
import 'dart:io';
import 'package:http/http.dart' as http;
import 'dart:typed_data';

import 'package:device_info_plus/device_info_plus.dart';
import 'package:easy_localization/easy_localization.dart';
import 'package:html/dom.dart';
import 'package:http/http.dart';
import 'package:obtainium/app_sources/apkmirror.dart';
import 'package:obtainium/app_sources/apkpure.dart';
import 'package:obtainium/app_sources/aptoide.dart';
import 'package:obtainium/app_sources/codeberg.dart';
import 'package:obtainium/app_sources/directAPKLink.dart';
import 'package:obtainium/app_sources/fdroid.dart';
import 'package:obtainium/app_sources/fdroidrepo.dart';
import 'package:obtainium/app_sources/github.dart';
import 'package:obtainium/app_sources/gitlab.dart';
import 'package:obtainium/app_sources/huaweiappgallery.dart';
import 'package:obtainium/app_sources/izzyondroid.dart';
import 'package:obtainium/app_sources/html.dart';
import 'package:obtainium/app_sources/jenkins.dart';
import 'package:obtainium/app_sources/neutroncode.dart';
import 'package:obtainium/app_sources/rustore.dart';
import 'package:obtainium/app_sources/sourceforge.dart';
import 'package:obtainium/app_sources/sourcehut.dart';
import 'package:obtainium/app_sources/telegramapp.dart';
import 'package:obtainium/app_sources/tencent.dart';
import 'package:obtainium/app_sources/uptodown.dart';
import 'package:obtainium/components/generated_form.dart';
import 'package:obtainium/custom_errors.dart';
import 'package:obtainium/mass_app_sources/githubstars.dart';
import 'package:obtainium/providers/logs_provider.dart';
import 'package:obtainium/providers/settings_provider.dart';

class AppNames {
  late String author;
  late String name;

  AppNames(this.author, this.name);
}

class APKDetails {
  late String version;
  late List<MapEntry<String, String>> apkUrls;
  late AppNames names;
  late DateTime? releaseDate;
  late String? changeLog;
  late List<MapEntry<String, String>> allAssetUrls;

  APKDetails(this.version, this.apkUrls, this.names,
      {this.releaseDate, this.changeLog, this.allAssetUrls = const []});
}

stringMapListTo2DList(List<MapEntry<String, String>> mapList) =>
    mapList.map((e) => [e.key, e.value]).toList();

assumed2DlistToStringMapList(List<dynamic> arr) =>
    arr.map((e) => MapEntry(e[0] as String, e[1] as String)).toList();

// App JSON schema has changed multiple times over the many versions of Obtainium
// This function takes an App JSON and modifies it if needed to conform to the latest (current) version
appJSONCompatibilityModifiers(Map<String, dynamic> json) {
  var source = SourceProvider()
      .getSource(json['url'], overrideSource: json['overrideSource']);
  var formItems = source.combinedAppSpecificSettingFormItems
      .reduce((value, element) => [...value, ...element]);
  Map<String, dynamic> additionalSettings =
      getDefaultValuesFromFormItems([formItems]);
  Map<String, dynamic> originalAdditionalSettings = {};
  if (json['additionalSettings'] != null) {
    originalAdditionalSettings =
        Map<String, dynamic>.from(jsonDecode(json['additionalSettings']));
    additionalSettings.addEntries(originalAdditionalSettings.entries);
  }
  // If needed, migrate old-style additionalData to newer-style additionalSettings (V1)
  if (json['additionalData'] != null) {
    List<String> temp = List<String>.from(jsonDecode(json['additionalData']));
    temp.asMap().forEach((i, value) {
      if (i < formItems.length) {
        if (formItems[i] is GeneratedFormSwitch) {
          additionalSettings[formItems[i].key] = value == 'true';
        } else {
          additionalSettings[formItems[i].key] = value;
        }
      }
    });
    additionalSettings['trackOnly'] =
        json['trackOnly'] == 'true' || json['trackOnly'] == true;
    additionalSettings['noVersionDetection'] =
        json['noVersionDetection'] == 'true' || json['trackOnly'] == true;
  }
  // Convert bool style version detection options to dropdown style
  if (additionalSettings['noVersionDetection'] == true) {
    additionalSettings['versionDetection'] = 'noVersionDetection';
    if (additionalSettings['releaseDateAsVersion'] == true) {
      additionalSettings['versionDetection'] = 'releaseDateAsVersion';
      additionalSettings.remove('releaseDateAsVersion');
    }
    if (additionalSettings['noVersionDetection'] != null) {
      additionalSettings.remove('noVersionDetection');
    }
    if (additionalSettings['releaseDateAsVersion'] != null) {
      additionalSettings.remove('releaseDateAsVersion');
    }
  }
  // Convert dropdown style version detection options back into bool style
  if (additionalSettings['versionDetection'] == 'standardVersionDetection') {
    additionalSettings['versionDetection'] = true;
  } else if (additionalSettings['versionDetection'] == 'noVersionDetection') {
    additionalSettings['versionDetection'] = false;
  } else if (additionalSettings['versionDetection'] == 'releaseDateAsVersion') {
    additionalSettings['versionDetection'] = false;
    additionalSettings['releaseDateAsVersion'] = true;
  }
  // Convert bool style pseudo version method to dropdown style
  if (originalAdditionalSettings['supportFixedAPKURL'] == true) {
    additionalSettings['defaultPseudoVersioningMethod'] = 'partialAPKHash';
  } else if (originalAdditionalSettings['supportFixedAPKURL'] == false) {
    additionalSettings['defaultPseudoVersioningMethod'] = 'APKLinkHash';
  }
  // Ensure additionalSettings are correctly typed
  for (var item in formItems) {
    if (additionalSettings[item.key] != null) {
      additionalSettings[item.key] =
          item.ensureType(additionalSettings[item.key]);
    }
  }
  int preferredApkIndex =
      json['preferredApkIndex'] == null ? 0 : json['preferredApkIndex'] as int;
  if (preferredApkIndex < 0) {
    preferredApkIndex = 0;
  }
  json['preferredApkIndex'] = preferredApkIndex;
  // apkUrls can either be old list or new named list apkUrls
  List<MapEntry<String, String>> apkUrls = [];
  if (json['apkUrls'] != null) {
    var apkUrlJson = jsonDecode(json['apkUrls']);
    try {
      apkUrls = getApkUrlsFromUrls(List<String>.from(apkUrlJson));
    } catch (e) {
      apkUrls = assumed2DlistToStringMapList(List<dynamic>.from(apkUrlJson));
      apkUrls = List<dynamic>.from(apkUrlJson)
          .map((e) => MapEntry(e[0] as String, e[1] as String))
          .toList();
    }
    json['apkUrls'] = jsonEncode(stringMapListTo2DList(apkUrls));
  }
  // Arch based APK filter option should be disabled if it previously did not exist
  if (additionalSettings['autoApkFilterByArch'] == null) {
    additionalSettings['autoApkFilterByArch'] = false;
  }
  // GitHub "don't sort" option to new dropdown format
  if (additionalSettings['dontSortReleasesList'] == true) {
    additionalSettings['sortMethodChoice'] = 'none';
  }
  if (source.runtimeType == HTML().runtimeType) {
    // HTML key rename
    if (originalAdditionalSettings['sortByFileNamesNotLinks'] != null) {
      additionalSettings['sortByLastLinkSegment'] =
          originalAdditionalSettings['sortByFileNamesNotLinks'];
    }
    // HTML single 'intermediate link' should be converted to multi-support version
    if (originalAdditionalSettings['intermediateLinkRegex'] != null &&
        additionalSettings['intermediateLinkRegex']?.isNotEmpty != true) {
      additionalSettings['intermediateLink'] = [
        {
          'customLinkFilterRegex':
              originalAdditionalSettings['intermediateLinkRegex'],
          'filterByLinkText':
              originalAdditionalSettings['intermediateLinkByText']
        }
      ];
    }
    if ((additionalSettings['intermediateLink']?.length ?? 0) > 0) {
      additionalSettings['intermediateLink'] =
          additionalSettings['intermediateLink'].where((e) {
        return e['customLinkFilterRegex']?.isNotEmpty == true;
      }).toList();
    }
    // Steam source apps should be converted to HTML (#1244)
    var legacySteamSourceApps = ['steam', 'steam-chat-app'];
    if (legacySteamSourceApps.contains(additionalSettings['app'] ?? '')) {
      json['url'] = '${json['url']}/mobile';
      var replacementAdditionalSettings = getDefaultValuesFromFormItems(
          HTML().combinedAppSpecificSettingFormItems);
      for (var s in replacementAdditionalSettings.keys) {
        if (additionalSettings.containsKey(s)) {
          replacementAdditionalSettings[s] = additionalSettings[s];
        }
      }
      replacementAdditionalSettings['customLinkFilterRegex'] =
          '/${additionalSettings['app']}-(([0-9]+\\.?){1,})\\.apk';
      replacementAdditionalSettings['versionExtractionRegEx'] =
          replacementAdditionalSettings['customLinkFilterRegex'];
      replacementAdditionalSettings['matchGroupToUse'] = '\$1';
      additionalSettings = replacementAdditionalSettings;
    }
    // Signal apps from before it was removed should be converted to HTML (#1928)
    if (json['url'] == 'https://signal.org' &&
        json['id'] == 'org.thoughtcrime.securesms' &&
        json['author'] == 'Signal' &&
        json['name'] == 'Signal' &&
        json['overrideSource'] == null &&
        additionalSettings['trackOnly'] == false &&
        additionalSettings['versionExtractionRegEx'] == '' &&
        json['lastUpdateCheck'] != null) {
      json['url'] = 'https://updates.signal.org/android/latest.json';
      var replacementAdditionalSettings = getDefaultValuesFromFormItems(
          HTML().combinedAppSpecificSettingFormItems);
      replacementAdditionalSettings['versionExtractionRegEx'] =
          '\\d+.\\d+.\\d+';
      additionalSettings = replacementAdditionalSettings;
    }
    // WhatsApp from before it was removed should be converted to HTML (#1943)
    if (json['url'] == 'https://whatsapp.com' &&
        json['id'] == 'com.whatsapp' &&
        json['author'] == 'Meta' &&
        json['name'] == 'WhatsApp' &&
        json['overrideSource'] == null &&
        additionalSettings['trackOnly'] == false &&
        additionalSettings['versionExtractionRegEx'] == '' &&
        json['lastUpdateCheck'] != null) {
      json['url'] = 'https://whatsapp.com/android';
      var replacementAdditionalSettings = getDefaultValuesFromFormItems(
          HTML().combinedAppSpecificSettingFormItems);
      replacementAdditionalSettings['refreshBeforeDownload'] = true;
      additionalSettings = replacementAdditionalSettings;
    }
    // VLC from before it was removed should be converted to HTML (#1943)
    if (json['url'] == 'https://videolan.org' &&
        json['id'] == 'org.videolan.vlc' &&
        json['author'] == 'VideoLAN' &&
        json['name'] == 'VLC' &&
        json['overrideSource'] == null &&
        additionalSettings['trackOnly'] == false &&
        additionalSettings['versionExtractionRegEx'] == '' &&
        json['lastUpdateCheck'] != null) {
      json['url'] = 'https://www.videolan.org/vlc/download-android.html';
      var replacementAdditionalSettings = getDefaultValuesFromFormItems(
          HTML().combinedAppSpecificSettingFormItems);
      replacementAdditionalSettings['refreshBeforeDownload'] = true;
      replacementAdditionalSettings['intermediateLink'] =
          <Map<String, dynamic>>[
        {
          'customLinkFilterRegex': 'APK',
          'filterByLinkText': true,
          'skipSort': false,
          'reverseSort': false,
          'sortByLastLinkSegment': false
        },
        {
          'customLinkFilterRegex': 'arm64-v8a\\.apk\$',
          'filterByLinkText': false,
          'skipSort': false,
          'reverseSort': false,
          'sortByLastLinkSegment': false
        }
      ];
      replacementAdditionalSettings['versionExtractionRegEx'] =
          '/vlc-android/([^/]+)/';
      replacementAdditionalSettings['matchGroupToUse'] = "1";
      additionalSettings = replacementAdditionalSettings;
    }
  }
  json['additionalSettings'] = jsonEncode(additionalSettings);
  // F-Droid no longer needs cloudflare exception since override can be used - migrate apps appropriately
  // This allows us to reverse the changes made for issue #418 (support cloudflare.f-droid)
  // While not causing problems for existing apps from that source that were added in a previous version
  var overrideSourceWasUndefined = !json.keys.contains('overrideSource');
  if ((json['url'] as String).startsWith('https://cloudflare.f-droid.org')) {
    json['overrideSource'] = FDroid().runtimeType.toString();
  } else if (overrideSourceWasUndefined) {
    // Similar to above, but for third-party F-Droid repos
    RegExpMatch? match = RegExp('^https?://.+/fdroid/([^/]+(/|\\?)|[^/]+\$)')
        .firstMatch(json['url'] as String);
    if (match != null) {
      json['overrideSource'] = FDroidRepo().runtimeType.toString();
    }
  }
  return json;
}

class App {
  late String id;
  late String url;
  late String author;
  late String name;
  String? installedVersion;
  late String latestVersion;
  List<MapEntry<String, String>> apkUrls = []; // Key is name, value is URL
  List<MapEntry<String, String>> otherAssetUrls = [];
  late int preferredApkIndex;
  late Map<String, dynamic> additionalSettings;
  late DateTime? lastUpdateCheck;
  bool pinned = false;
  List<String> categories;
  late DateTime? releaseDate;
  late String? changeLog;
  late String? overrideSource;
  bool allowIdChange = false;
  App(
      this.id,
      this.url,
      this.author,
      this.name,
      this.installedVersion,
      this.latestVersion,
      this.apkUrls,
      this.preferredApkIndex,
      this.additionalSettings,
      this.lastUpdateCheck,
      this.pinned,
      {this.categories = const [],
      this.releaseDate,
      this.changeLog,
      this.overrideSource,
      this.allowIdChange = false,
      this.otherAssetUrls = const []});

  @override
  String toString() {
    return 'ID: $id URL: $url INSTALLED: $installedVersion LATEST: $latestVersion APK: $apkUrls PREFERREDAPK: $preferredApkIndex ADDITIONALSETTINGS: ${additionalSettings.toString()} LASTCHECK: ${lastUpdateCheck.toString()} PINNED $pinned';
  }

  String? get overrideName =>
      additionalSettings['appName']?.toString().trim().isNotEmpty == true
          ? additionalSettings['appName']
          : null;

  String get finalName {
    return overrideName ?? name;
  }

  String? get overrideAuthor =>
      additionalSettings['appAuthor']?.toString().trim().isNotEmpty == true
          ? additionalSettings['appAuthor']
          : null;

  String get finalAuthor {
    return overrideAuthor ?? author;
  }

  App deepCopy() => App(
      id,
      url,
      author,
      name,
      installedVersion,
      latestVersion,
      apkUrls,
      preferredApkIndex,
      Map.from(additionalSettings),
      lastUpdateCheck,
      pinned,
      categories: categories,
      changeLog: changeLog,
      releaseDate: releaseDate,
      overrideSource: overrideSource,
      allowIdChange: allowIdChange,
      otherAssetUrls: otherAssetUrls);

  factory App.fromJson(Map<String, dynamic> json) {
    Map<String, dynamic> originalJSON = Map.from(json);
    try {
      json = appJSONCompatibilityModifiers(json);
    } catch (e) {
      json = originalJSON;
      LogsProvider().add(
          'Error running JSON compat modifiers: ${e.toString()}: ${originalJSON.toString()}');
    }
    return App(
      json['id'] as String,
      json['url'] as String,
      json['author'] as String,
      json['name'] as String,
      json['installedVersion'] == null
          ? null
          : json['installedVersion'] as String,
      (json['latestVersion'] ?? tr('unknown')) as String,
      assumed2DlistToStringMapList(
          jsonDecode((json['apkUrls'] ?? '[["placeholder", "placeholder"]]'))),
      (json['preferredApkIndex'] ?? -1) as int,
      jsonDecode(json['additionalSettings']) as Map<String, dynamic>,
      json['lastUpdateCheck'] == null
          ? null
          : DateTime.fromMicrosecondsSinceEpoch(json['lastUpdateCheck']),
      json['pinned'] ?? false,
      categories: json['categories'] != null
          ? (json['categories'] as List<dynamic>)
              .map((e) => e.toString())
              .toList()
          : json['category'] != null
              ? [json['category'] as String]
              : [],
      releaseDate: json['releaseDate'] == null
          ? null
          : DateTime.fromMicrosecondsSinceEpoch(json['releaseDate']),
      changeLog: json['changeLog'] == null ? null : json['changeLog'] as String,
      overrideSource: json['overrideSource'],
      allowIdChange: json['allowIdChange'] ?? false,
      otherAssetUrls: assumed2DlistToStringMapList(
          jsonDecode((json['otherAssetUrls'] ?? '[]'))),
    );
  }

  Map<String, dynamic> toJson() => {
        'id': id,
        'url': url,
        'author': author,
        'name': name,
        'installedVersion': installedVersion,
        'latestVersion': latestVersion,
        'apkUrls': jsonEncode(stringMapListTo2DList(apkUrls)),
        'otherAssetUrls': jsonEncode(stringMapListTo2DList(otherAssetUrls)),
        'preferredApkIndex': preferredApkIndex,
        'additionalSettings': jsonEncode(additionalSettings),
        'lastUpdateCheck': lastUpdateCheck?.microsecondsSinceEpoch,
        'pinned': pinned,
        'categories': categories,
        'releaseDate': releaseDate?.microsecondsSinceEpoch,
        'changeLog': changeLog,
        'overrideSource': overrideSource,
        'allowIdChange': allowIdChange
      };
}

// Ensure the input is starts with HTTPS and has no WWW
preStandardizeUrl(String url) {
  var firstDotIndex = url.indexOf('.');
  if (!(firstDotIndex >= 0 && firstDotIndex != url.length - 1)) {
    throw UnsupportedURLError();
  }
  if (url.toLowerCase().indexOf('http://') != 0 &&
      url.toLowerCase().indexOf('https://') != 0) {
    url = 'https://$url';
  }
  var uri = Uri.tryParse(url);
  var trailingSlash = ((uri?.path.endsWith('/') ?? false) ||
          ((uri?.path.isEmpty ?? false) && url.endsWith('/'))) &&
      (uri?.queryParameters.isEmpty ?? false);

  url = url
          .split('/')
          .where((e) => e.isNotEmpty)
          .join('/')
          .replaceFirst(':/', '://') +
      (trailingSlash ? '/' : '');
  return url;
}

String noAPKFound = tr('noAPKFound');

List<String> getLinksFromParsedHTML(
        Document dom, RegExp hrefPattern, String prependToLinks) =>
    dom
        .querySelectorAll('a')
        .where((element) {
          if (element.attributes['href'] == null) return false;
          return hrefPattern.hasMatch(element.attributes['href']!);
        })
        .map((e) => '$prependToLinks${e.attributes['href']!}')
        .toList();

Map<String, dynamic> getDefaultValuesFromFormItems(
    List<List<GeneratedFormItem>> items) {
  return Map.fromEntries(items
      .map((row) => row.map((el) => MapEntry(el.key, el.defaultValue ?? '')))
      .reduce((value, element) => [...value, ...element]));
}

List<MapEntry<String, String>> getApkUrlsFromUrls(List<String> urls) =>
    urls.map((e) {
      var segments = e.split('/').where((el) => el.trim().isNotEmpty);
      var apkSegs = segments.where((s) => s.toLowerCase().endsWith('.apk'));
      return MapEntry(apkSegs.isNotEmpty ? apkSegs.last : segments.last, e);
    }).toList();

Future<List<MapEntry<String, String>>> filterApksByArch(
    List<MapEntry<String, String>> apkUrls) async {
  if (apkUrls.length > 1) {
    var abis = (await DeviceInfoPlugin().androidInfo).supportedAbis;
    for (var abi in abis) {
      var urls2 = apkUrls
          .where((element) => RegExp('.*$abi.*').hasMatch(element.key))
          .toList();
      if (urls2.isNotEmpty && urls2.length < apkUrls.length) {
        apkUrls = urls2;
        break;
      }
    }
  }
  return apkUrls;
}

getSourceRegex(List<String> hosts) {
  return '(${hosts.join('|').replaceAll('.', '\\.')})';
}

HttpClient createHttpClient(bool insecure) {
  final client = HttpClient();
  if (insecure) {
    client.badCertificateCallback =
        (X509Certificate cert, String host, int port) => true;
  }
  return client;
}

abstract class AppSource {
  List<String> hosts = [];
  bool hostChanged = false;
  bool hostIdenticalDespiteAnyChange = false;
  late String name;
  bool enforceTrackOnly = false;
  bool changeLogIfAnyIsMarkDown = true;
  bool appIdInferIsOptional = false;
  bool allowSubDomains = false;
  bool naiveStandardVersionDetection = false;
  bool neverAutoSelect = false;
  bool showReleaseDateAsVersionToggle = false;
  bool versionDetectionDisallowed = false;
  List<String> excludeCommonSettingKeys = [];
  bool urlsAlwaysHaveExtension = false;

  AppSource() {
    name = runtimeType.toString();
  }

  overrideAdditionalAppSpecificSourceAgnosticSettingSwitch(String key,
      {bool disabled = true, bool defaultValue = true}) {
    additionalAppSpecificSourceAgnosticSettingFormItemsNeverUseDirectly =
        additionalAppSpecificSourceAgnosticSettingFormItemsNeverUseDirectly
            .map((e) {
      return e.map((e2) {
        if (e2.key == key) {
          var item = e2 as GeneratedFormSwitch;
          item.disabled = disabled;
          item.defaultValue = defaultValue;
        }
        return e2;
      }).toList();
    }).toList();
  }

  String standardizeUrl(String url) {
    url = preStandardizeUrl(url);
    if (!hostChanged) {
      url = sourceSpecificStandardizeURL(url);
    }
    return url;
  }

  Future<Map<String, String>?> getRequestHeaders(
      Map<String, dynamic> additionalSettings,
      {bool forAPKDownload = false}) async {
    return null;
  }

  App endOfGetAppChanges(App app) {
    return app;
  }

  Future<Response> sourceRequest(
      String url, Map<String, dynamic> additionalSettings,
      {bool followRedirects = true, Object? postBody}) async {
    var requestHeaders = await getRequestHeaders(additionalSettings);

    if (requestHeaders != null || followRedirects == false) {
      var method = postBody == null ? 'GET' : 'POST';
      var currentUrl = url;
      var redirectCount = 0;
      const maxRedirects = 10;
      while (redirectCount < maxRedirects) {
        var httpClient =
            createHttpClient(additionalSettings['allowInsecure'] == true);
        var request = await httpClient.openUrl(method, Uri.parse(currentUrl));
        if (requestHeaders != null) {
          requestHeaders.forEach((key, value) {
            request.headers.set(key, value);
          });
        }
        request.followRedirects = false;
        if (postBody != null) {
          request.headers.contentType = ContentType.json;
          request.write(jsonEncode(postBody));
        }
        final response = await request.close();

        if (followRedirects &&
            (response.statusCode == 301 || response.statusCode == 302)) {
          final location = response.headers.value(HttpHeaders.locationHeader);
          if (location != null) {
            currentUrl = location;
            redirectCount++;
            httpClient.close();
            continue;
          }
        }

        final bytes = (await response.fold<BytesBuilder>(
                BytesBuilder(), (b, d) => b..add(d)))
            .toBytes();

        final headers = <String, String>{};
        response.headers.forEach((name, values) {
          headers[name] = values.join(', ');
        });

        httpClient.close();

        return http.Response.bytes(
          bytes,
          response.statusCode,
          headers: headers,
          request: http.Request(method, Uri.parse(url)),
        );
      }
      throw ObtainiumError('Too many redirects ($maxRedirects)');
    } else {
      return postBody == null
          ? http.get(Uri.parse(url))
          : http.post(Uri.parse(url), body: jsonEncode(postBody));
    }
  }

  void runOnAddAppInputChange(String inputUrl) {
    //
  }

  String sourceSpecificStandardizeURL(String url, {bool forSelection = false}) {
    throw NotImplementedError();
  }

  Future<APKDetails> getLatestAPKDetails(
      String standardUrl, Map<String, dynamic> additionalSettings) {
    throw NotImplementedError();
  }

  // Different Sources may need different kinds of additional data for Apps
  List<List<GeneratedFormItem>> additionalSourceAppSpecificSettingFormItems =
      [];

  // Some additional data may be needed for Apps regardless of Source
  List<List<GeneratedFormItem>>
      additionalAppSpecificSourceAgnosticSettingFormItemsNeverUseDirectly = [
    [
      GeneratedFormSwitch(
        'trackOnly',
        label: tr('trackOnly'),
      )
    ],
    [
      GeneratedFormTextField('versionExtractionRegEx',
          label: tr('trimVersionString'),
          required: false,
          additionalValidators: [(value) => regExValidator(value)]),
    ],
    [
      GeneratedFormTextField('matchGroupToUse',
          label: tr('matchGroupToUseForX', args: [tr('trimVersionString')]),
          required: false,
          hint: '\$0')
    ],
    [
      GeneratedFormSwitch('versionDetection',
          label: tr('versionDetectionExplanation'), defaultValue: true)
    ],
    [
      GeneratedFormSwitch('useVersionCodeAsOSVersion',
          label: tr('useVersionCodeAsOSVersion'), defaultValue: false)
    ],
    [
      GeneratedFormTextField('apkFilterRegEx',
          label: tr('filterAPKsByRegEx'),
          required: false,
          additionalValidators: [
            (value) {
              return regExValidator(value);
            }
          ])
    ],
    [
      GeneratedFormSwitch('invertAPKFilter',
          label: '${tr('invertRegEx')} (${tr('filterAPKsByRegEx')})',
          defaultValue: false)
    ],
    [
      GeneratedFormSwitch('autoApkFilterByArch',
          label: tr('autoApkFilterByArch'), defaultValue: true)
    ],
    [GeneratedFormTextField('appName', label: tr('appName'), required: false)],
    [GeneratedFormTextField('appAuthor', label: tr('author'), required: false)],
    [
      GeneratedFormSwitch('shizukuPretendToBeGooglePlay',
          label: tr('shizukuPretendToBeGooglePlay'), defaultValue: false)
    ],
    [
      GeneratedFormSwitch('allowInsecure',
          label: tr('allowInsecure'), defaultValue: false)
    ],
    [
      GeneratedFormSwitch('exemptFromBackgroundUpdates',
          label: tr('exemptFromBackgroundUpdates'))
    ],
    [
      GeneratedFormSwitch('skipUpdateNotifications',
          label: tr('skipUpdateNotifications'))
    ],
    [GeneratedFormTextField('about', label: tr('about'), required: false)],
    [
      GeneratedFormSwitch('refreshBeforeDownload',
          label: tr('refreshBeforeDownload'))
    ]
  ];

  // Previous 2 variables combined into one at runtime for convenient usage
  List<List<GeneratedFormItem>> get combinedAppSpecificSettingFormItems {
    if (showReleaseDateAsVersionToggle == true) {
      if (additionalAppSpecificSourceAgnosticSettingFormItemsNeverUseDirectly
              .indexWhere((List<GeneratedFormItem> e) =>
                  e.indexWhere((GeneratedFormItem i) =>
                      i.key == 'releaseDateAsVersion') >=
                  0) <
          0) {
        additionalAppSpecificSourceAgnosticSettingFormItemsNeverUseDirectly.insert(
            additionalAppSpecificSourceAgnosticSettingFormItemsNeverUseDirectly
                    .indexWhere((List<GeneratedFormItem> e) =>
                        e.indexWhere((GeneratedFormItem i) =>
                            i.key == 'versionDetection') >=
                        0) +
                1,
            [
              GeneratedFormSwitch('releaseDateAsVersion',
                  label:
                      '${tr('releaseDateAsVersion')} (${tr('pseudoVersion')})',
                  defaultValue: false)
            ]);
      }
    }
    additionalAppSpecificSourceAgnosticSettingFormItemsNeverUseDirectly =
        additionalAppSpecificSourceAgnosticSettingFormItemsNeverUseDirectly
            .map((e) => e
                .where((ee) => !excludeCommonSettingKeys.contains(ee.key))
                .toList())
            .where((e) => e.isNotEmpty)
            .toList();
    if (versionDetectionDisallowed) {
      overrideAdditionalAppSpecificSourceAgnosticSettingSwitch(
          'versionDetection',
          disabled: true,
          defaultValue: false);
      overrideAdditionalAppSpecificSourceAgnosticSettingSwitch(
          'useVersionCodeAsOSVersion',
          disabled: true,
          defaultValue: false);
    }
    return [
      ...additionalSourceAppSpecificSettingFormItems,
      ...additionalAppSpecificSourceAgnosticSettingFormItemsNeverUseDirectly
    ];
  }

  // Some Sources may have additional settings at the Source level (not specific to Apps) - these use SettingsProvider
  // If the source has been overridden, we expect the user to define one-time values as additional settings - don't use the stored values
  List<GeneratedFormItem> sourceConfigSettingFormItems = [];
  Future<Map<String, String>> getSourceConfigValues(
      Map<String, dynamic> additionalSettings,
      SettingsProvider settingsProvider) async {
    Map<String, String> results = {};
    for (var e in sourceConfigSettingFormItems) {
      var val = hostChanged && !hostIdenticalDespiteAnyChange
          ? additionalSettings[e.key]
          : additionalSettings[e.key] ??
              settingsProvider.getSettingString(e.key);
      if (val != null) {
        results[e.key] = val;
      }
    }
    return results;
  }

  String? changeLogPageFromStandardUrl(String standardUrl) {
    return null;
  }

  Future<String?> getSourceNote() async {
    return null;
  }

  Future<String> apkUrlPrefetchModifier(String apkUrl, String standardUrl,
      Map<String, dynamic> additionalSettings) async {
    return apkUrl;
  }

  bool canSearch = false;
  bool includeAdditionalOptsInMainSearch = false;
  List<GeneratedFormItem> searchQuerySettingFormItems = [];
  Future<Map<String, List<String>>> search(String query,
      {Map<String, dynamic> querySettings = const {}}) {
    throw NotImplementedError();
  }

  Future<String?> tryInferringAppId(String standardUrl,
      {Map<String, dynamic> additionalSettings = const {}}) async {
    return null;
  }
}

ObtainiumError getObtainiumHttpError(Response res) {
  return ObtainiumError((res.reasonPhrase != null &&
          res.reasonPhrase != null &&
          res.reasonPhrase!.isNotEmpty)
      ? res.reasonPhrase!
      : tr('errorWithHttpStatusCode', args: [res.statusCode.toString()]));
}

abstract class MassAppUrlSource {
  late String name;
  late List<String> requiredArgs;
  Future<Map<String, List<String>>> getUrlsWithDescriptions(List<String> args);
}

regExValidator(String? value) {
  if (value == null || value.isEmpty) {
    return null;
  }
  try {
    RegExp(value);
  } catch (e) {
    return tr('invalidRegEx');
  }
  return null;
}

intValidator(String? value, {bool positive = false}) {
  if (value == null) {
    return tr('invalidInput');
  }
  var num = int.tryParse(value);
  if (num == null) {
    return tr('invalidInput');
  }
  if (positive && num <= 0) {
    return tr('invalidInput');
  }
  return null;
}

bool isTempId(App app) {
  // return app.id == generateTempID(app.url, app.additionalSettings);
  return RegExp('^[0-9]+\$').hasMatch(app.id);
}

replaceMatchGroupsInString(RegExpMatch match, String matchGroupString) {
  if (RegExp('^\\d+\$').hasMatch(matchGroupString)) {
    matchGroupString = '\$$matchGroupString';
  }
  // Regular expression to match numbers in the input string
  final numberRegex = RegExp(r'\$\d+');
  // Extract all numbers from the input string
  final numbers = numberRegex.allMatches(matchGroupString);
  if (numbers.isEmpty) {
    // If no numbers found, return the original string
    return null;
  }
  // Replace numbers with corresponding match groups
  var outputString = matchGroupString;
  for (final numberMatch in numbers) {
    final number = numberMatch.group(0)!;
    final matchGroup = match.group(int.parse(number.substring(1))) ?? '';
    // Check if the number is preceded by a single backslash
    final isEscaped = outputString.contains('\\$number');
    // Replace the number with the corresponding match group
    if (!isEscaped) {
      outputString = outputString.replaceAll(number, matchGroup);
    } else {
      outputString = outputString.replaceAll('\\$number', number);
    }
  }
  return outputString;
}

String? extractVersion(String? versionExtractionRegEx, String? matchGroupString,
    String stringToCheck) {
  if (versionExtractionRegEx?.isNotEmpty == true) {
    String? version = stringToCheck;
    var match = RegExp(versionExtractionRegEx!).allMatches(version);
    if (match.isEmpty) {
      throw NoVersionError();
    }
    matchGroupString = matchGroupString?.trim() ?? '';
    if (matchGroupString.isEmpty) {
      matchGroupString = "0";
    }
    version = replaceMatchGroupsInString(match.last, matchGroupString);
    if (version?.isNotEmpty != true) {
      throw NoVersionError();
    }
    return version!;
  } else {
    return null;
  }
}

List<MapEntry<String, String>> filterApks(
    List<MapEntry<String, String>> apkUrls,
    String? apkFilterRegEx,
    bool? invert) {
  if (apkFilterRegEx?.isNotEmpty == true) {
    var reg = RegExp(apkFilterRegEx!);
    apkUrls = apkUrls.where((element) {
      var hasMatch = reg.hasMatch(element.key);
      return invert == true ? !hasMatch : hasMatch;
    }).toList();
  }
  return apkUrls;
}

class SourceProvider {
  // Add more source classes here so they are available via the service
  List<AppSource> get sources => [
        GitHub(),
        GitLab(),
        Codeberg(),
        FDroid(),
        FDroidRepo(),
        IzzyOnDroid(),
        SourceHut(),
        APKPure(),
        Aptoide(),
        Uptodown(),
        HuaweiAppGallery(),
        Tencent(),
        Jenkins(),
        APKMirror(),
        RuStore(),
        TelegramApp(),
        NeutronCode(),
        DirectAPKLink(),
        HTML() // This should ALWAYS be the last option as they are tried in order
      ];

  // Add more mass url source classes here so they are available via the service
  List<MassAppUrlSource> massUrlSources = [GitHubStars()];

  AppSource getSource(String url, {String? overrideSource}) {
    url = preStandardizeUrl(url);
    if (overrideSource != null) {
      var srcs =
          sources.where((e) => e.runtimeType.toString() == overrideSource);
      if (srcs.isEmpty) {
        throw UnsupportedURLError();
      }
      var res = srcs.first;
      var originalHosts = res.hosts;
      var newHost = Uri.parse(url).host;
      res.hosts = [newHost];
      res.hostChanged = true;
      if (originalHosts.contains(newHost)) {
        res.hostIdenticalDespiteAnyChange = true;
      }
      return res;
    }
    AppSource? source;
    for (var s in sources.where((element) => element.hosts.isNotEmpty)) {
      try {
        if (RegExp(
                '^${s.allowSubDomains ? '([^\\.]+\\.)*' : '(www\\.)?'}(${getSourceRegex(s.hosts)})\$')
            .hasMatch(Uri.parse(url).host)) {
          source = s;
          break;
        }
      } catch (e) {
        // Ignore
      }
    }
    if (source == null) {
      for (var s in sources.where(
          (element) => element.hosts.isEmpty && !element.neverAutoSelect)) {
        try {
          s.sourceSpecificStandardizeURL(url, forSelection: true);
          source = s;
          break;
        } catch (e) {
          //
        }
      }
    }
    if (source == null) {
      throw UnsupportedURLError();
    }
    return source;
  }

  bool ifRequiredAppSpecificSettingsExist(AppSource source) {
    for (var row in source.combinedAppSpecificSettingFormItems) {
      for (var element in row) {
        if (element is GeneratedFormTextField && element.required) {
          return true;
        }
      }
    }
    return false;
  }

  String generateTempID(
          String standardUrl, Map<String, dynamic> additionalSettings) =>
      (standardUrl + additionalSettings.toString()).hashCode.toString();

  Future<App> getApp(
      AppSource source, String url, Map<String, dynamic> additionalSettings,
      {App? currentApp,
      bool trackOnlyOverride = false,
      bool sourceIsOverriden = false,
      bool inferAppIdIfOptional = false}) async {
    if (trackOnlyOverride || source.enforceTrackOnly) {
      additionalSettings['trackOnly'] = true;
    }
    var trackOnly = additionalSettings['trackOnly'] == true;
    String standardUrl = source.standardizeUrl(url);
    APKDetails apk =
        await source.getLatestAPKDetails(standardUrl, additionalSettings);

    if (source.runtimeType !=
            HTML().runtimeType && // Some sources do it separately
        source.runtimeType != SourceForge().runtimeType) {
      String? extractedVersion = extractVersion(
          additionalSettings['versionExtractionRegEx'] as String?,
          additionalSettings['matchGroupToUse'] as String?,
          apk.version);
      if (extractedVersion != null) {
        apk.version = extractedVersion;
      }
    }

    if (additionalSettings['releaseDateAsVersion'] == true &&
        apk.releaseDate != null) {
      apk.version = apk.releaseDate!.microsecondsSinceEpoch.toString();
    }
    apk.apkUrls = filterApks(apk.apkUrls, additionalSettings['apkFilterRegEx'],
        additionalSettings['invertAPKFilter']);
    if (apk.apkUrls.isEmpty && !trackOnly) {
      throw NoAPKError();
    }
    if (additionalSettings['autoApkFilterByArch'] == true) {
      apk.apkUrls = await filterApksByArch(apk.apkUrls);
    }
    var name = currentApp != null ? currentApp.name.trim() : '';
    name = name.isNotEmpty ? name : apk.names.name;
    App finalApp = App(
        currentApp?.id ??
            ((additionalSettings['appId'] != null)
                ? additionalSettings['appId']
                : null) ??
            (!trackOnly &&
                    (!source.appIdInferIsOptional ||
                        (source.appIdInferIsOptional && inferAppIdIfOptional))
                ? await source.tryInferringAppId(standardUrl,
                    additionalSettings: additionalSettings)
                : null) ??
            generateTempID(standardUrl, additionalSettings),
        standardUrl,
        apk.names.author,
        name,
        currentApp?.installedVersion,
        apk.version,
        apk.apkUrls,
        apk.apkUrls.length - 1 >= 0 ? apk.apkUrls.length - 1 : 0,
        additionalSettings,
        DateTime.now(),
        currentApp?.pinned ?? false,
        categories: currentApp?.categories ?? const [],
        releaseDate: apk.releaseDate,
        changeLog: apk.changeLog,
        overrideSource: sourceIsOverriden
            ? source.runtimeType.toString()
            : currentApp?.overrideSource,
        allowIdChange: currentApp?.allowIdChange ??
            trackOnly ||
                (source.appIdInferIsOptional &&
                    inferAppIdIfOptional), // Optional ID inferring may be incorrect - allow correction on first install
        otherAssetUrls: apk.allAssetUrls
            .where((a) => apk.apkUrls.indexWhere((p) => a.key == p.key) < 0)
            .toList());
    return source.endOfGetAppChanges(finalApp);
  }

  // Returns errors in [results, errors] instead of throwing them
  Future<List<dynamic>> getAppsByURLNaive(List<String> urls,
      {List<String> alreadyAddedUrls = const [],
      AppSource? sourceOverride}) async {
    List<App> apps = [];
    Map<String, dynamic> errors = {};
    for (var url in urls) {
      try {
        if (alreadyAddedUrls.contains(url)) {
          throw ObtainiumError(tr('appAlreadyAdded'));
        }
        var source = sourceOverride ?? getSource(url);
        apps.add(await getApp(
            source,
            url,
            sourceIsOverriden: sourceOverride != null,
            getDefaultValuesFromFormItems(
                source.combinedAppSpecificSettingFormItems)));
      } catch (e) {
        errors.addAll(<String, dynamic>{url: e});
      }
    }
    return [apps, errors];
  }
}