client.dart

import 'dart:async';
import 'dart:io';
import 'dart:ui';

import 'package:bugsnag_flutter/src/error_factory.dart';
import 'package:flutter/foundation.dart';
import 'package:flutter/scheduler.dart';
import 'package:flutter/services.dart';
import 'package:flutter/widgets.dart' show WidgetsFlutterBinding;

import 'callbacks.dart';
import 'config.dart';
import 'enum_utils.dart';
import 'last_run_info.dart';
import 'model.dart';

final _notifier = {
  'name': 'Flutter Bugsnag Notifier',
  'url': 'https://github.com/bugsnag/bugsnag-flutter',
  'version': '3.1.0'
};

abstract class BugsnagClient {

  final Map<String, Stopwatch> _openNetworkRequests = {};

  /// An utility error handling function that will send reported errors to
  /// Bugsnag as unhandled. The [errorHandler] is suitable for use with
  /// common Dart error callbacks such as [runZonedGuarded] or [Future.onError].
  void Function(dynamic error, StackTrace? stack) get errorHandler;

  /// Sets the user information to be associated with events
  Future<void> setUser({String? id, String? email, String? name});

  /// Returns the currently set User information.
  Future<BugsnagUser> getUser();

  /// Bugsnag uses the concept of “contexts” to help display and group your
  /// errors. The context represents what was happening in your application
  /// at the time an error occurs and is given high visual prominence in
  /// the dashboard.
  ///
  /// The "context" can be made to follow your app navigation by using the
  /// [BugsnagNavigatorObserver] in your application of `Navigator`:
  /// ```dart
  /// return MaterialApp(
  ///   navigatorObservers: [BugsnagNavigatorObserver(setContext: true)],
  /// ```
  ///
  /// See also:
  /// - [getContext]
  /// - [BugsnagNavigatorObserver]
  Future<void> setContext(String? context);

  /// Bugsnag uses the concept of “contexts” to help display and group your
  /// errors. The context represents what was happening in your application
  /// at the time an error occurs and is given high visual prominence in
  /// the dashboard.
  ///
  /// See also:
  /// - [setContext]
  /// - [BugsnagNavigatorObserver]
  Future<String?> getContext();

  /// Leave a "breadcrumb" log message, representing an action that occurred
  /// in your app, to aid with debugging.
  ///
  /// [message] is a short label to identify the action that occurred, while
  /// [metadata] can contain useful information associated with the action.
  ///
  /// See also:
  /// - [getBreadcrumbs]
  /// - [BugsnagMetadata.sanitizedMap]
  Future<void> leaveBreadcrumb(
    String message, {
    Map<String, Object>? metadata,
    BugsnagBreadcrumbType type = BugsnagBreadcrumbType.manual,
  });

  /// Returns the current buffer of breadcrumbs that will be sent with captured
  /// events. This ordered list represents the most recent breadcrumbs to be
  /// captured up to the limit set in [start].
  Future<List<BugsnagBreadcrumb>> getBreadcrumbs();

  /// Add a single feature flag with an optional variant. If there is an
  /// existing feature flag with the same name, it will be overwritten with the
  /// new variant.
  ///
  /// See also:
  /// - [addFeatureFlags]
  /// - [clearFeatureFlag]
  /// - [clearFeatureFlags]
  Future<void> addFeatureFlag(String name, [String? variant]);

  /// Add a collection of feature flags. This has the same effect as calling
  /// [addFeatureFlag] for each value passed, but it typically faster when there
  /// are more than one `FeatureFlag`.
  ///
  /// See also:
  /// - [addFeatureFlag]
  /// - [clearFeatureFlag]
  /// - [clearFeatureFlags]
  Future<void> addFeatureFlags(List<BugsnagFeatureFlag> featureFlags);

  /// Remove a single feature flag regardless of its current status. This will
  /// stop the specified feature flag from being reported. If the named feature
  /// flag does not exist this will have no effect.
  ///
  /// See also:
  /// - [addFeatureFlag]
  /// - [addFeatureFlags]
  /// - [clearFeatureFlags]
  Future<void> clearFeatureFlag(String name);

  /// Clear all of the feature flags. This will stop all feature flags from
  /// being reported.
  ///
  /// See also:
  /// - [addFeatureFlag]
  /// - [addFeatureFlags]
  /// - [clearFeatureFlag]
  Future<void> clearFeatureFlags();

  /// Adds a map of multiple metadata key-value pairs to the specified section.
  /// ```dart
  /// bugsnag.addMetadata('account', const {'name': 'Acme. Co.'});
  /// ```
  ///
  /// See also:
  /// - [BugsnagMetadata.sanitizedMap]
  /// - [getMetadata]
  /// - [clearMetadata]
  Future<void> addMetadata(String section, Map<String, Object> metadata);

  /// If [key] is not `null`: removes data with the specified key from the
  /// specified section. Otherwise remove all the data from the specified
  /// [section].
  Future<void> clearMetadata(String section, [String? key]);

  /// Returns a map of data in the specified section.
  Future<Map<String, Object>?> getMetadata(String section);

  /// Starts tracking a new session. You should disable automatic session
  /// by setting `autoTrackSessions` to `false` in [start].
  ///
  /// You should call this at the appropriate time in your application when you
  /// wish to start a session. Any subsequent errors which occur in your
  /// application will still be reported to Bugsnag but will not count towards
  /// your application's [stability score](https://docs.bugsnag.com/product/releases/releases-dashboard/#stability-score).
  /// This will start a new session even if there is already an existing
  /// session; you should call [resumeSession] if you only want to start a
  /// session when one doesn't already exist.
  ///
  /// See also:
  /// - [pauseSession]
  /// - [resumeSession]
  Future<void> startSession();

  /// Pauses tracking of a session. You should disable automatic session
  /// by setting `autoTrackSessions` to `false` in [start].
  ///
  /// You should call this at the appropriate time in your application when you
  /// wish to pause a session. Any subsequent errors which occur in your
  /// application will still be reported to Bugsnag but will not count towards
  /// your application's [stability score](https://docs.bugsnag.com/product/releases/releases-dashboard/#stability-score).
  /// This can be advantageous if, for example, you do not wish the stability
  /// score to include crashes in a background service.
  ///
  /// See also:
  /// - [startSession]
  /// - [resumeSession]
  Future<void> pauseSession();

  /// Resumes a session which has previously been paused, or starts a new
  /// session if none exists. If a session has already been resumed or started
  /// and has not been paused, calling this method will have no effect.
  /// You should disable automatic session by setting `autoTrackSessions`
  /// to `false` in [start] if you call this method.
  ///
  /// It's important to note that sessions are stored in memory for the lifetime
  /// of the application process and are not persisted on disk. Therefore
  /// calling this method on app startup would start a new session, rather
  /// than continuing any previous session.
  ///
  /// You should call this at the appropriate time in your application when you
  /// wish to resume a previously started session. Any subsequent errors which
  /// occur in your application will still be reported to Bugsnag but will not
  /// count towards your application's [stability score](https://docs.bugsnag.com/product/releases/releases-dashboard/#stability-score).
  ///
  /// See also:
  /// - [startSession]
  /// - [pauseSession]
  Future<bool> resumeSession();

  /// Informs Bugsnag that the application has finished launching. Once this
  /// has resolved [BugsnagAppWithState.isLaunching] will always be false in any new
  /// error reports, and synchronous delivery will not be attempted on the next
  /// launch for any fatal crashes.
  Future<void> markLaunchCompleted();

  /// Retrieves information about the last launch of the application, if it
  /// has been run before.
  ///
  /// For example, this allows checking whether the app crashed on its last
  /// launch, which could be used to perform conditional behaviour to recover
  /// from crashes, such as clearing the app data cache.
  Future<BugsnagLastRunInfo?> getLastRunInfo();

  /// Notify Bugsnag of a handled exception.
  ///
  /// The [callback] can be specified to modify the generated event before it
  /// is delivered to Bugsnag.
  Future<void> notify(
    dynamic error,
    StackTrace? stackTrace, {
    BugsnagOnErrorCallback? callback,
  });

  /// Add a "on error" callback, to execute code at the point where an error
  /// report is captured in Bugsnag.
  ///
  /// You can use this to add or modify information attached to an [event](BugsnagEvent)
  /// before it is sent to your dashboard. You can also return `false` from any
  /// callback to prevent delivery.
  ///
  /// ```dart
  /// bugsnag.addOnError((event) {
  ///   event.severity = Severity.info;
  ///   return true;
  /// });
  /// ```
  ///
  /// "on error" callbacks added here are only triggered for events originating
  /// in Dart and will always be triggered before "on error" callbacks added
  /// in the native layer (on Android and iOS).
  void addOnError(BugsnagOnErrorCallback onError);

  /// Removes a previously added "on error" callback.
  void removeOnError(BugsnagOnErrorCallback onError);

  networkInstrumentation(dynamic data) {
    try {
      if (data is! Map<String, dynamic>) return;
      String? status = data["status"];
      String? requestId = data["request_id"];
      if (requestId == null || status == null) return;

      if (status == "started") {
        _onRequestStarted(requestId);
      } else if (status == "complete") {
        _onRequestComplete(requestId, data);
      }
    } catch (e) {
      // Fail silently
    }
  }

  void _onRequestStarted(String requestId) {
      final stopwatch = Stopwatch()..start();
      _openNetworkRequests[requestId] = stopwatch;
  }

  void _onRequestComplete(String requestId, dynamic data) {
      final stopwatch = _openNetworkRequests.remove(requestId);
      if (stopwatch != null && data is Map<String, dynamic>) {
        final duration = stopwatch.elapsedMilliseconds;
        final String? clientName = data["client"];
        if (clientName == null) return;

        String params = "";
        final url = data["url"];
        final splitUrl = url.split("?");
        if (splitUrl != null && splitUrl.length > 1) {
          params = splitUrl.last;
        }
        final int? statusCode = data["status_code"];
        if (statusCode == null) return;

        final String status = statusCode < 400 ? "succeeded" : "failed";
        // Assuming leaveBreadcrumb is a predefined method to log the event
        leaveBreadcrumb("$clientName request $status", metadata: {
          "duration": duration,
          "method": data["http_method"],
          "url": splitUrl.first,
          if(params.isNotEmpty)
              "urlParams": params,
          if(data["request_content_length"] != null && data["request_content_length"] > 0)
              "requestContentLength": data["request_content_length"],
          if(data["response_content_length"] != null && data["response_content_length"] > 0)
              "responseContentLength": data["response_content_length"],
          "status": statusCode,
          },
          type: BugsnagBreadcrumbType.request,
        );
      }
  }

}

mixin DelegateClient implements BugsnagClient {
  BugsnagClient? _client;

  BugsnagClient get client {
    final localClient = _client;
    if (localClient == null) {
      throw Exception(
          'You must start or attach bugsnag before calling any other methods');
    }

    return localClient;
  }

  set client(BugsnagClient client) {
    _client = client;
  }

  @override
  void Function(dynamic error, StackTrace? stack) get errorHandler =>
      client.errorHandler;

  @override
  Future<BugsnagUser> getUser() => client.getUser();

  @override
  Future<void> setUser({String? id, String? email, String? name}) =>
      client.setUser(id: id, email: email, name: name);

  @override
  Future<void> setContext(String? context) => client.setContext(context);

  @override
  Future<String?> getContext() => client.getContext();

  @override
  Future<void> leaveBreadcrumb(
    String message, {
    Map<String, Object>? metadata,
    BugsnagBreadcrumbType type = BugsnagBreadcrumbType.manual,
  }) =>
      client.leaveBreadcrumb(message, metadata: metadata, type: type);

  @override
  Future<List<BugsnagBreadcrumb>> getBreadcrumbs() => client.getBreadcrumbs();

  @override
  Future<void> addFeatureFlag(String name, [String? variant]) =>
      client.addFeatureFlag(name, variant);

  @override
  Future<void> addFeatureFlags(List<BugsnagFeatureFlag> featureFlags) =>
      client.addFeatureFlags(featureFlags);

  @override
  Future<void> clearFeatureFlag(String name) => client.clearFeatureFlag(name);

  @override
  Future<void> clearFeatureFlags() => client.clearFeatureFlags();

  @override
  Future<void> addMetadata(String section, Map<String, Object> metadata) =>
      client.addMetadata(section, metadata);

  @override
  Future<void> clearMetadata(String section, [String? key]) =>
      client.clearMetadata(section, key);

  @override
  Future<Map<String, Object>?> getMetadata(String section) =>
      client.getMetadata(section);

  @override
  Future<void> startSession() => client.startSession();

  @override
  Future<void> pauseSession() => client.pauseSession();

  @override
  Future<bool> resumeSession() => client.resumeSession();

  @override
  Future<void> markLaunchCompleted() => client.markLaunchCompleted();

  @override
  Future<BugsnagLastRunInfo?> getLastRunInfo() => client.getLastRunInfo();

  @override
  Future<void> notify(
    dynamic error,
    StackTrace? stackTrace, {
    BugsnagOnErrorCallback? callback,
  }) =>
      client.notify(error, stackTrace, callback: callback);

  @override
  void addOnError(BugsnagOnErrorCallback onError) => client.addOnError(onError);

  @override
  void removeOnError(BugsnagOnErrorCallback onError) =>
      client.removeOnError(onError);
}

class ChannelClient extends BugsnagClient {
  FlutterExceptionHandler? _previousFlutterOnError;
  ErrorCallback? _previousPlatformDispatcherOnError;

  ChannelClient(bool autoDetectErrors) {
    if (autoDetectErrors) {
      // as ChannelClient is the only implementation that can run within the
      // same Isolate as Flutter, we install the FlutterError handler here
      _previousFlutterOnError = FlutterError.onError;
      FlutterError.onError = _onFlutterError;
      _previousPlatformDispatcherOnError = PlatformDispatcher.instance.onError;
      PlatformDispatcher.instance.onError = _onDispatcherError;
    }
  }

  static const MethodChannel _channel =
      MethodChannel('com.bugsnag/client', JSONMethodCodec());

  final CallbackCollection<BugsnagEvent> _onErrorCallbacks = {};

  @override
  void Function(dynamic error, StackTrace? stack) get errorHandler =>
      _notifyUnhandled;

  @override
  Future<BugsnagUser> getUser() async =>
      BugsnagUser.fromJson(await _channel.invokeMethod('getUser'));

  @override
  Future<void> setUser({String? id, String? email, String? name}) =>
      _channel.invokeMethod(
        'setUser',
        BugsnagUser(id: id, email: email, name: name),
      );

  @override
  Future<void> setContext(String? context) =>
      _channel.invokeMethod('setContext', {'context': context});

  @override
  Future<String?> getContext() => _channel.invokeMethod('getContext');

  @override
  Future<void> leaveBreadcrumb(
    String message, {
    Map<String, Object>? metadata,
    BugsnagBreadcrumbType type = BugsnagBreadcrumbType.manual,
  }) async {
    final crumb = BugsnagBreadcrumb(message, type: type, metadata: metadata);
    await _channel.invokeMethod('leaveBreadcrumb', crumb);
  }

  @override
  Future<List<BugsnagBreadcrumb>> getBreadcrumbs() async =>
      List.from((await _channel.invokeMethod('getBreadcrumbs') as List)
          .map((e) => BugsnagBreadcrumb.fromJson(e)));

  @override
  Future<void> addFeatureFlag(String name, [String? variant]) => _channel
      .invokeMethod('addFeatureFlags', [BugsnagFeatureFlag(name, variant)]);

  @override
  Future<void> addFeatureFlags(List<BugsnagFeatureFlag> featureFlags) =>
      _channel.invokeMethod('addFeatureFlags', featureFlags);

  @override
  Future<void> clearFeatureFlag(String name) =>
      _channel.invokeMethod('clearFeatureFlag', {'name': name});

  @override
  Future<void> clearFeatureFlags() =>
      _channel.invokeMethod('clearFeatureFlags');

  @override
  Future<void> addMetadata(String section, Map<String, Object> metadata) =>
      _channel.invokeMethod('addMetadata', {
        'section': section,
        'metadata': BugsnagMetadata.sanitizedMap(metadata),
      });

  @override
  Future<void> clearMetadata(String section, [String? key]) =>
      _channel.invokeMethod('clearMetadata', {
        'section': section,
        if (key != null) 'key': key,
      });

  @override
  Future<Map<String, Object>?> getMetadata(String section) async {
    final metadata = await _channel.invokeMethod(
      'getMetadata',
      {'section': section},
    );

    return (metadata != null) ? Map.from(metadata).cast() : null;
  }

  @override
  Future<void> startSession() => _channel.invokeMethod('startSession');

  @override
  Future<void> pauseSession() => _channel.invokeMethod('pauseSession');

  @override
  Future<bool> resumeSession() async =>
      await _channel.invokeMethod('resumeSession') as bool;

  @override
  Future<void> markLaunchCompleted() =>
      _channel.invokeMethod('markLaunchCompleted');

  @override
  Future<BugsnagLastRunInfo?> getLastRunInfo() async {
    final json = await _channel.invokeMethod('getLastRunInfo');
    return (json == null) ? null : BugsnagLastRunInfo.fromJson(json);
  }

  @override
  void addOnError(BugsnagOnErrorCallback onError) {
    _onErrorCallbacks.add(onError);
  }

  @override
  void removeOnError(BugsnagOnErrorCallback onError) {
    _onErrorCallbacks.remove(onError);
  }

  void _onFlutterError(FlutterErrorDetails details) {
    _notifyInternal(details.exception, true, details, details.stack, null);
    _previousFlutterOnError?.call(details);
  }

  bool _onDispatcherError(Object exception, StackTrace stack) {
    _notifyInternal(exception, true, null, stack, null);
    return _previousPlatformDispatcherOnError?.call(exception, stack) ?? false;
  }

  Future<void> _notifyInternal(
    dynamic error,
    bool unhandled,
    FlutterErrorDetails? details,
    StackTrace? stackTrace,
    BugsnagOnErrorCallback? callback,
  ) async {
    final errorPayload =
        BugsnagErrorFactory.instance.createError(error, stackTrace);
    final event = await _createEvent(
      errorPayload,
      details: details,
      unhandled: unhandled,
      deliver: _onErrorCallbacks.isEmpty && callback == null,
    );

    if (event == null) {
      return;
    }

    if (!await _onErrorCallbacks.dispatch(event)) {
      // callback rejected the payload - so we don't deliver it
      return;
    }

    if (callback != null && !await callback.invokeSafely(event)) {
      // callback rejected the payload - so we don't deliver it
      return;
    }

    await _deliverEvent(event);
  }

  @override
  Future<void> notify(
    dynamic error,
    StackTrace? stackTrace, {
    BugsnagOnErrorCallback? callback,
  }) {
    return _notifyInternal(error, false, null, stackTrace, callback);
  }

  void _notifyUnhandled(dynamic error, StackTrace? stackTrace) {
    _notifyInternal(error, true, null, stackTrace, null);
  }

  /// Create an Event by having it built by the native notifier,
  /// if [deliver] is `true` return `null` and schedule the `Event` for immediate
  /// delivery. If [deliver] is `false` then the `Event` is only constructed
  /// and returned to be processed by the Flutter notifier.
  Future<BugsnagEvent?> _createEvent(
    BugsnagError error, {
    FlutterErrorDetails? details,
    required bool unhandled,
    required bool deliver,
  }) async {
    final buildID = error.stacktrace.isNotEmpty
        ? error.stacktrace.first.codeIdentifier
        : null;
    final errorInfo = details?.informationCollector?.call() ?? [];
    final errorContext = details?.context?.toDescription();
    final errorLibrary = details?.library;
    // SchedulerBinding.instance is nullable in Flutter <3.0.0
    // ignore: unnecessary_cast
    final schedulerBinding = SchedulerBinding.instance as SchedulerBinding?;
    final lifecycleState = schedulerBinding?.lifecycleState.toString();
    final metadata = {
      if (buildID != null) 'buildID': buildID,
      if (errorContext != null) 'errorContext': errorContext,
      if (errorLibrary != null) 'errorLibrary': errorLibrary,
      if (errorInfo.isNotEmpty)
        'errorInformation':
            (StringBuffer()..writeAll(errorInfo, '\n')).toString(),
      'defaultRouteName': PlatformDispatcher.instance.defaultRouteName,
      'initialLifecycleState':
          PlatformDispatcher.instance.initialLifecycleState,
      if (lifecycleState != null) 'lifecycleState': lifecycleState,
    };
    final eventJson = await _channel.invokeMethod(
      'createEvent',
      {
        'error': error,
        'flutterMetadata': metadata,
        'unhandled': unhandled,
        'deliver': deliver
      },
    );

    if (eventJson != null) {
      return BugsnagEvent.fromJson(eventJson);
    }

    return null;
  }

  Future<void> _deliverEvent(BugsnagEvent event) =>
      _channel.invokeMethod('deliverEvent', event);

  @override
  networkInstrumentation(data) {}
}

/// The primary `Client`. Typically this class is not accessed directly, and
/// is instead accessed using the [bugsnag] global:
///
/// ```dart
/// Future<void> main() async {
///   await bugsnag.start(apiKey: 'your-api-key');
///   runApp(MyApplication());
/// }
/// ```
///
/// See also:
/// - [start]
class Bugsnag extends BugsnagClient with DelegateClient {
  Bugsnag._internal();

  /// Attach Bugsnag to an already initialised native notifier, optionally
  /// adding to its existing configuration. Use [start] if your application
  /// is entirely built in Flutter.
  ///
  /// Typical hybrid Flutter applications with Bugsnag will start with
  /// ```dart
  /// Future<void> main() async {
  ///  await bugsnag.attach(
  ///   // configuration here
  ///   );
  ///   runApp(MyApplication());
  /// }
  /// ```
  ///
  /// Use this method to initialize Flutter when developing a Hybrid app,
  /// where Bugsnag is being started by the native part of the app. For more
  /// information on starting Bugsnag natively, see our platform guides for:
  ///
  /// - Android: <https://docs.bugsnag.com/platforms/android/>
  /// - iOS: <https://docs.bugsnag.com/platforms/ios/>
  ///
  /// See also:
  ///
  /// - [start]
  /// - [setUser]
  /// - [setContext]
  /// - [addFeatureFlags]
  /// - [addOnError]
  Future<void> attach({
    List<BugsnagOnErrorCallback> onError = const [],
  }) async {
    // make sure we can use Channels
    WidgetsFlutterBinding.ensureInitialized();

    final result = await ChannelClient._channel.invokeMethod('attach', {
      'notifier': _notifier,
    });

    final autoDetectErrors =
        result['config']['enabledErrorTypes']['dartErrors'] as bool;

    final client = ChannelClient(autoDetectErrors);
    client._onErrorCallbacks.addAll(onError);
    this.client = client;
  }

  /// Initialize the Bugsnag notifier with the configuration options specified.
  /// Use [attach] if you are building a Hybrid application where Bugsnag
  /// is initialised by the Native layer.
  ///
  /// [start] will pick up any native configuration options that are specified.
  ///
  /// Typical Flutter-only applications with Bugsnag will start with:
  /// ```dart
  /// Future<void> main() async {
  ///   await bugsnag.start(apiKey: 'your-api-key');
  ///   runApp(MyApplication());
  /// }
  /// ```
  ///
  /// See also:
  ///
  /// - [attach]
  /// - [setUser]
  /// - [setContext]
  /// - [addFeatureFlags]
  /// - [addOnError]
  Future<void> start({
    String? apiKey,
    BugsnagUser? user,
    bool persistUser = true,
    String? context,
    String? appType,
    String? appVersion,
    String? bundleVersion,
    String? releaseStage,
    BugsnagEnabledErrorTypes enabledErrorTypes = BugsnagEnabledErrorTypes.all,
    BugsnagEndpointConfiguration endpoints =
        BugsnagEndpointConfiguration.bugsnag,
    int maxBreadcrumbs = 50,
    int maxPersistedSessions = 128,
    int maxPersistedEvents = 32,
    int maxStringValueLength = 10000,
    bool autoTrackSessions = true,
    bool autoDetectErrors = true,
    BugsnagThreadSendPolicy sendThreads = BugsnagThreadSendPolicy.always,
    int launchDurationMillis = 5000,
    bool sendLaunchCrashesSynchronously = true,
    int appHangThresholdMillis = appHangThresholdFatalOnly,
    Set<String> redactedKeys = const {'password'},
    Set<String> discardClasses = const {},
    Set<String>? enabledReleaseStages,
    Set<BugsnagEnabledBreadcrumbType>? enabledBreadcrumbTypes,
    BugsnagProjectPackages projectPackages =
        const BugsnagProjectPackages.withDefaults({}),
    Map<String, Map<String, Object>>? metadata,
    List<BugsnagFeatureFlag>? featureFlags,
    List<BugsnagOnErrorCallback> onError = const [],
    BugsnagTelemetryTypes telemetry = BugsnagTelemetryTypes.all,
    Directory? persistenceDirectory,
    int? versionCode,
  }) async {
    final detectDartErrors =
        autoDetectErrors && enabledErrorTypes.unhandledDartExceptions;

    if (projectPackages._includeDefaults) {
      projectPackages += BugsnagProjectPackages.only(_findProjectPackages());
    }

    // make sure we can use Channels
    WidgetsFlutterBinding.ensureInitialized();

    await ChannelClient._channel.invokeMethod('start', <String, dynamic>{
      if (apiKey != null) 'apiKey': apiKey,
      if (user != null) 'user': user,
      'persistUser': persistUser,
      if (context != null) 'context': context,
      if (appType != null) 'appType': appType,
      if (appVersion != null) 'appVersion': appVersion,
      if (bundleVersion != null) 'bundleVersion': bundleVersion,
      if (releaseStage != null) 'releaseStage': releaseStage,
      'enabledErrorTypes': enabledErrorTypes,
      'endpoints': endpoints,
      'maxBreadcrumbs': maxBreadcrumbs,
      'maxPersistedSessions': maxPersistedSessions,
      'maxPersistedEvents': maxPersistedEvents,
      'maxStringValueLength': maxStringValueLength,
      'autoTrackSessions': autoTrackSessions,
      'autoDetectErrors': autoDetectErrors,
      'sendThreads': sendThreads.toName(),
      'launchDurationMillis': launchDurationMillis,
      'sendLaunchCrashesSynchronously': sendLaunchCrashesSynchronously,
      'appHangThresholdMillis': appHangThresholdMillis,
      'redactedKeys': List<String>.from(redactedKeys),
      'discardClasses': List<String>.from(discardClasses),
      if (enabledReleaseStages != null)
        'enabledReleaseStages': enabledReleaseStages.toList(),
      'enabledBreadcrumbTypes':
          (enabledBreadcrumbTypes ?? BugsnagEnabledBreadcrumbType.values)
              .map((e) => e.toName())
              .toList(),
      'projectPackages': projectPackages,
      if (metadata != null) 'metadata': BugsnagMetadata(metadata),
      'featureFlags': featureFlags,
      'notifier': _notifier,
      'telemetry': telemetry,
      if (persistenceDirectory != null)
        'persistenceDirectory': persistenceDirectory.absolute.path,
      if (versionCode != null) 'versionCode': versionCode,
    });

    final client = ChannelClient(detectDartErrors);
    client._onErrorCallbacks.addAll(onError);
    this.client = client;

    if (autoTrackSessions) {
      await resumeSession().onError((error, stackTrace) => true);
    }
  }

  static const int appHangThresholdFatalOnly = 2147483647;

  static Set<String> _findProjectPackages() {
    try {
      final frames = StackFrame.fromStackTrace(StackTrace.current);
      final lastBugsnag = frames.lastIndexWhere((f) =>
          f.packageScheme == 'package' && f.package == 'bugsnag_flutter');

      if (lastBugsnag != -1 && lastBugsnag < frames.length) {
        final package = frames[lastBugsnag + 1].package;
        if (package.isNotEmpty && package != 'null') {
          return {package};
        }
      }
    } catch (e) {
      // deliberately ignored, we return null
    }

    return const <String>{};
  }

}

/// In order to determine where a crash happens Bugsnag needs to know which
/// packages you consider to be part of your app (as opposed to a library).
///
/// By default this is set according to the  underlying platform (e.g. Android)
/// and an attempt is made to discover the Dart package your app uses.
/// This detection *will not work* if you build using `--split-debug-info`.
///
/// See also:
/// - [Bugsnag.start]
/// - [BugsnagProjectPackages.defaults]
class BugsnagProjectPackages {
  final bool _includeDefaults;
  final Set<String> _packageNames;

  const BugsnagProjectPackages._internal(
    this._packageNames,
    this._includeDefaults,
  );

  /// Specify the exact list of package names to consider as part of the
  /// project. This should include packages from both Dart and any Java packages
  /// your application uses on Android.
  ///
  /// This does not include any [defaults](ProjectPackages.withDefaults).
  const BugsnagProjectPackages.only(Set<String> packageNames)
      : this._internal(packageNames, false);

  /// Combine the given set of `packageNames` with the default packages.
  /// This is useful when you are using `--split-debug-info` and so need to
  /// specify your Dart packages in [Bugsnag.start].
  ///
  /// See also:
  /// - [Android Configuration.projectPackages](https://docs.bugsnag.com/platforms/android/configuration-options/#projectpackages)
  const BugsnagProjectPackages.withDefaults(Set<String> additionalPackageNames)
      : this._internal(additionalPackageNames, true);

  operator +(BugsnagProjectPackages other) => BugsnagProjectPackages._internal(
      _packageNames.union(other._packageNames),
      _includeDefaults || other._includeDefaults);

  dynamic toJson() => <String, dynamic>{
        'includeDefaults': _includeDefaults,
        'packageNames': List.from(_packageNames),
      };
}

/// Primary access to the Bugsnag API, most calls to Bugsnag will start here
final Bugsnag bugsnag = Bugsnag._internal();