fix(analytics): use Android ID and persist UUID fallbacks (#1624)

ui/flutter/lib/api/model/downloader_config.dart

@@ -196,7 +196,9 @@ class ExtraConfig {
   List<String> createHistory;
   bool runAsMenubarApp;
   bool analyticsEnabled;
-  String analyticsClientId;
+
+  /// Persisted UUID fallback; IDs returned by platform APIs are not stored here.
+  String deviceId;
 
   ExtraConfig({
     this.themeMode = '',
@@ -214,7 +216,7 @@ class ExtraConfig {
     this.createHistory = const [],
     this.runAsMenubarApp = false,
     this.analyticsEnabled = true,
-    this.analyticsClientId = '',
+    this.deviceId = '',
   }) : windowState = windowState ?? WindowStateConfig();
 
   factory ExtraConfig.fromJson(Map<String, dynamic>? json) =>

ui/flutter/lib/api/model/downloader_config.g.dart

@@ -193,7 +193,7 @@ ExtraConfig _$ExtraConfigFromJson(Map<String, dynamic> json) => ExtraConfig(
   createHistory: (json['createHistory'] as List<dynamic>?)?.map((e) => e as String).toList() ?? const [],
   runAsMenubarApp: json['runAsMenubarApp'] as bool? ?? false,
   analyticsEnabled: json['analyticsEnabled'] as bool? ?? true,
-  analyticsClientId: json['analyticsClientId'] as String? ?? '',
+  deviceId: json['deviceId'] as String? ?? '',
 );
 
 Map<String, dynamic> _$ExtraConfigToJson(ExtraConfig instance) => <String, dynamic>{
@@ -212,7 +212,7 @@ Map<String, dynamic> _$ExtraConfigToJson(ExtraConfig instance) => <String, dynam
   'createHistory': instance.createHistory,
   'runAsMenubarApp': instance.runAsMenubarApp,
   'analyticsEnabled': instance.analyticsEnabled,
-  'analyticsClientId': instance.analyticsClientId,
+  'deviceId': instance.deviceId,
 };
 
 WindowStateConfig _$WindowStateConfigFromJson(Map<String, dynamic> json) => WindowStateConfig(

ui/flutter/lib/app/application/app_runtime_controller.dart

@@ -255,9 +255,9 @@ class AppRuntimeController extends AsyncNotifier<AppRuntimeState> {
   Future<void> _initAnalytics(DownloaderConfig config) async {
     if (!AnalyticsConfig.isConfigured || !config.extra.analyticsEnabled) return;
     try {
-      await Analytics.instance.init(fallbackClientId: config.extra.analyticsClientId);
-      if (config.extra.analyticsClientId.isEmpty && Analytics.instance.clientId.isNotEmpty) {
-        config.extra.analyticsClientId = Analytics.instance.clientId;
+      final generatedClientId = await Analytics.instance.init(fallbackClientId: config.extra.deviceId);
+      if (generatedClientId != null) {
+        config.extra.deviceId = generatedClientId;
         await ref.read(gopeedServiceProvider).putConfig(config);
       }
       unawaited(Analytics.instance.logAppOpen());

ui/flutter/lib/features/settings/application/settings_controller.dart

@@ -56,7 +56,7 @@ class SettingsController extends AsyncNotifier<SettingsState> {
         ..bookmarks = latest.extra.bookmarks
         ..createHistory = latest.extra.createHistory
         ..runAsMenubarApp = latest.extra.runAsMenubarApp
-        ..analyticsClientId = latest.extra.analyticsClientId;
+        ..deviceId = latest.extra.deviceId;
       // The backend preserves protocol-owned results and validates the whole PUT.
       await service.putConfig(config);
       final saved = await service.getConfig();

ui/flutter/lib/util/analytics.dart

@@ -1,8 +1,10 @@
 import 'dart:io';
 
+import 'package:android_id/android_id.dart';
 import 'package:device_info_plus/device_info_plus.dart';
 import 'package:dio/dio.dart';
 import 'package:flutter/foundation.dart';
+import 'package:uuid/uuid.dart';
 
 import 'log_util.dart';
 import 'package_info.dart';
@@ -31,12 +33,23 @@ class Analytics {
 
   String get clientId => _initialized ? _clientId : '';
 
-  Future<void> init({String fallbackClientId = ''}) async {
-    if (_initialized || !AnalyticsConfig.isConfigured) return;
-    _clientId = await _getDeviceId(fallbackClientId);
+  /// Returns a newly generated fallback ID for the caller to persist, if any.
+  Future<String?> init({String fallbackClientId = ''}) async {
+    if (_initialized || !AnalyticsConfig.isConfigured) return null;
+    final deviceId = await _getDeviceId();
+    String? generatedClientId;
+    if (deviceId != null && deviceId.isNotEmpty) {
+      _clientId = deviceId;
+    } else if (fallbackClientId.isNotEmpty) {
+      _clientId = fallbackClientId;
+    } else {
+      _clientId = const Uuid().v4();
+      generatedClientId = _clientId;
+    }
     _sessionId = DateTime.now().millisecondsSinceEpoch ~/ 1000;
     _dio = Dio(BaseOptions(connectTimeout: const Duration(seconds: 10), receiveTimeout: const Duration(seconds: 10)));
     _initialized = true;
+    return generatedClientId;
   }
 
   Future<void> logAppOpen() => logEvent('app_open');
@@ -70,14 +83,14 @@ class Analytics {
     }
   }
 
-  Future<String> _getDeviceId(String fallbackClientId) async {
+  Future<String?> _getDeviceId() async {
+    if (kIsWeb) return null;
+
     String? deviceId;
     try {
       final info = DeviceInfoPlugin();
-      if (kIsWeb) {
-        deviceId = null;
-      } else if (Platform.isAndroid) {
-        deviceId = (await info.androidInfo).id;
+      if (Platform.isAndroid) {
+        deviceId = await const AndroidId().getId();
       } else if (Platform.isIOS) {
         deviceId = (await info.iosInfo).identifierForVendor;
       } else if (Platform.isMacOS) {
@@ -91,14 +104,6 @@ class Analytics {
       logger.w('GA4Analytics: failed to read device id: $error');
     }
 
-    if (deviceId == null || deviceId.isEmpty) {
-      deviceId = fallbackClientId;
-      if (deviceId.isEmpty) {
-        final random = DateTime.now().microsecondsSinceEpoch % 2147483647;
-        final timestamp = DateTime.now().millisecondsSinceEpoch ~/ 1000;
-        deviceId = '$random.$timestamp';
-      }
-    }
     return deviceId;
   }