优化项目结构

lib/services/usage_stats_service.dart

@@ -0,0 +1,159 @@
+import 'dart:async';
+import 'dart:convert';
+import 'dart:io' show Platform;
+import 'package:crypto/crypto.dart';
+import 'package:device_info_plus/device_info_plus.dart';
+import 'package:flutter/material.dart';
+import 'package:http/http.dart' as http;
+import 'package:package_info_plus/package_info_plus.dart';
+import 'user_prefs.dart';
+import 'server_config.dart';
+
+/// 匿名用户统计服务（静默运行，对用户不可见）
+///
+/// App 启动后每 5 分钟向统计服务器发送匿名心跳。
+/// 统计数据在服务端管理后台查看，App 内无入口。
+class UsageStatsService with WidgetsBindingObserver {
+  static final UsageStatsService instance = UsageStatsService._();
+  UsageStatsService._();
+
+  final UserPrefs _prefs = UserPrefs();
+
+  /// 统计服务器地址，debug 走局域网，release 走线上
+  static String serverUrl = '${ServerConfig.baseUrl}/';
+  Timer? _heartbeatTimer;
+  bool _started = false;
+
+  static const _heartbeatInterval = Duration(minutes: 1);
+
+  /// 启动统计服务（App 启动时调用一次）
+  Future<void> start() async {
+    if (_started) return;
+    _started = true;
+
+    // 未配置服务器地址则直接跳过
+    if (serverUrl.isEmpty) return;
+
+    // 首次启动生成匿名设备ID
+    await _ensureDeviceId();
+
+    // 注册生命周期监听
+    WidgetsBinding.instance.addObserver(this);
+
+    // 立即发送一次心跳
+    await _sendHeartbeat();
+
+    // 启动定时心跳
+    _startTimer();
+  }
+
+  /// 停止统计服务
+  Future<void> stop() async {
+    if (!_started) return;
+    _started = false;
+    _heartbeatTimer?.cancel();
+    _heartbeatTimer = null;
+    WidgetsBinding.instance.removeObserver(this);
+  }
+
+  // ─── 内部方法 ──────────────────────────────────────────────────────────
+
+  /// 确保设备有匿名ID
+  Future<void> _ensureDeviceId() async {
+    if (_prefs.deviceId.isEmpty) {
+      final id = await _generateDeviceId();
+      await _prefs.setDeviceId(id);
+    }
+  }
+
+  /// 基于设备硬件信息生成匿名设备标识（SHA-256 哈希）
+  Future<String> _generateDeviceId() async {
+    final deviceInfo = DeviceInfoPlugin();
+    String rawId;
+
+    if (Platform.isAndroid) {
+      final info = await deviceInfo.androidInfo;
+      rawId = info.id; // Settings.Secure.ANDROID_ID
+    } else if (Platform.isIOS) {
+      final info = await deviceInfo.iosInfo;
+      rawId = info.identifierForVendor ?? '';
+    } else if (Platform.isWindows) {
+      final info = await deviceInfo.windowsInfo;
+      rawId = '${info.computerName}-${info.numberOfCores}';
+    } else if (Platform.isMacOS) {
+      final info = await deviceInfo.macOsInfo;
+      rawId = '${info.computerName}-${info.systemGUID ?? ''}';
+    } else if (Platform.isLinux) {
+      final info = await deviceInfo.linuxInfo;
+      rawId = '${info.name}-${info.id}';
+    } else {
+      rawId = DateTime.now().millisecondsSinceEpoch.toString();
+    }
+
+    final bytes = utf8.encode(rawId);
+    final hash = sha256.convert(bytes);
+    final hex = hash.toString();
+
+    // 格式化为 UUID 样式
+    return '${hex.substring(0, 8)}-'
+        '${hex.substring(8, 12)}-'
+        '${hex.substring(12, 16)}-'
+        '${hex.substring(16, 20)}-'
+        '${hex.substring(20, 32)}';
+  }
+
+  /// 发送心跳
+  Future<void> _sendHeartbeat() async {
+    if (serverUrl.isEmpty) return;
+    final deviceId = _prefs.deviceId;
+    if (deviceId.isEmpty) return;
+
+    try {
+      String appVersion = '';
+      try {
+        final pkgInfo = await PackageInfo.fromPlatform();
+        appVersion = '${pkgInfo.version}+${pkgInfo.buildNumber}';
+      } catch (_) {}
+
+      await http
+          .post(
+            Uri.parse('$serverUrl/api/heartbeat'),
+            headers: {'Content-Type': 'application/json'},
+            body: jsonEncode({
+              'device_hash': deviceId,
+              'device_type':
+                  Platform.operatingSystem, // android/ios/windows/macos/linux
+              'device_name':
+                  '${Platform.operatingSystem} ${Platform.operatingSystemVersion}',
+              'app_version': appVersion,
+            }),
+          )
+          .timeout(const Duration(seconds: 5));
+    } catch (_) {
+      // 静默失败，不影响主流程
+    }
+  }
+
+  /// 启动定时心跳
+  void _startTimer() {
+    _heartbeatTimer?.cancel();
+    _heartbeatTimer = Timer.periodic(_heartbeatInterval, (_) {
+      _sendHeartbeat();
+    });
+  }
+
+  // ─── 生命周期 ──────────────────────────────────────────────────────────
+
+  @override
+  void didChangeAppLifecycleState(AppLifecycleState state) {
+    if (state == AppLifecycleState.resumed) {
+      // 回到前台：立即发送心跳，恢复定时器
+      _sendHeartbeat();
+      _startTimer();
+    } else if (state == AppLifecycleState.paused) {
+      // 进入后台：停止定时器
+      _heartbeatTimer?.cancel();
+      _heartbeatTimer = null;
+    }
+  }
+}