优化

.claude/settings.local.json

@@ -43,7 +43,13 @@
       "Bash(flutter clean:*)",
       "Bash(start ms-settings:developers)",
       "Bash(gradlew.bat --stop:*)",
-      "Bash(call gradlew.bat:*)"
+      "Bash(call gradlew.bat:*)",
+      "Bash(where:*)",
+      "Bash(gradlew.bat:*)",
+      "Bash(if [ -d \"android/app/build/outputs\" ])",
+      "Bash(then find android/app/build/outputs -type f ( -name \"*.aab\" -o -name \"*.apk\" ))",
+      "Bash(else echo \"outputs 目录不存在，可能还未构建过\")",
+      "Bash(fi)"
     ],
     "deny": [],
     "ask": []

.trae/documents/FocusBuddy 代码优化计划.md

@@ -0,0 +1,208 @@
+# FocusBuddy 代码优化计划
+
+## 一、架构优化
+
+### 1. 统一服务层初始化模式
+- **问题**：当前服务层使用了不同的初始化模式（静态方法、单例、普通实例），导致代码不一致
+- **优化方案**：
+  - 将所有服务统一为单例模式或依赖注入模式
+  - 建立服务容器，统一管理服务实例
+  - 代码示例：
+    ```dart
+    // 统一服务初始化
+    class ServiceLocator {
+      static final ServiceLocator _instance = ServiceLocator._internal();
+      factory ServiceLocator() => _instance;
+      ServiceLocator._internal();
+      
+      late StorageService storageService;
+      late NotificationService notificationService;
+      late EncouragementService encouragementService;
+      
+      Future<void> initialize() async {
+        storageService = StorageService();
+        await storageService.init();
+        
+        notificationService = NotificationService();
+        await notificationService.initialize();
+        await notificationService.requestPermissions();
+        
+        encouragementService = EncouragementService();
+        await encouragementService.loadMessages();
+      }
+    }
+    ```
+
+### 2. 引入依赖注入
+- **问题**：当前服务依赖关系不清晰，难以进行单元测试
+- **优化方案**：
+  - 引入依赖注入框架（如 get_it 或 provider）
+  - 使服务之间的依赖关系显式化
+  - 提高代码的可测试性和可维护性
+
+## 二、性能优化
+
+### 1. 优化存储查询性能
+- **问题**：`StorageService.getTodaySessions()` 每次调用都会遍历所有会话，对于大量数据可能影响性能
+- **优化方案**：
+  - 添加缓存机制，缓存当天的会话数据
+  - 实现会话数据的索引，提高查询效率
+  - 代码示例：
+    ```dart
+    List<FocusSession>? _todaySessionsCache;
+    DateTime? _cacheDate;
+    
+    List<FocusSession> getTodaySessions() {
+      final now = DateTime.now();
+      final today = DateTime(now.year, now.month, now.day);
+      
+      // Check if cache is valid
+      if (_todaySessionsCache != null && _cacheDate == today) {
+        return _todaySessionsCache!;
+      }
+      
+      // Query and cache results
+      final sessions = _sessionsBox.values.where((session) {
+        final sessionDate = DateTime(
+          session.startTime.year,
+          session.startTime.month,
+          session.startTime.day,
+        );
+        return sessionDate == today;
+      }).toList();
+      
+      _todaySessionsCache = sessions;
+      _cacheDate = today;
+      return sessions;
+    }
+    ```
+
+### 2. 优化通知服务性能
+- **问题**：通知服务在初始化时进行了不必要的平台检查
+- **优化方案**：
+  - 延迟初始化通知服务，仅在需要时初始化
+  - 优化权限检查逻辑，避免重复请求权限
+
+## 三、代码质量优化
+
+### 1. 完善文档注释
+- **问题**：部分方法缺少文档注释，降低了代码的可维护性
+- **优化方案**：
+  - 为所有公共方法添加详细的文档注释
+  - 说明方法的用途、参数和返回值
+  - 示例：
+    ```dart
+    /// Save a focus session to local storage
+    /// 
+    /// [session] - The focus session to save
+    /// Returns a Future that completes when the session is saved
+    Future<void> saveFocusSession(FocusSession session) async {
+      await _sessionsBox.add(session);
+      _invalidateCache(); // Invalidate cache when data changes
+    }
+    ```
+
+### 2. 增强错误处理
+- **问题**：部分错误处理逻辑不够完善，可能导致应用崩溃
+- **优化方案**：
+  - 为所有异步操作添加 try-catch 块
+  - 实现统一的错误处理机制
+  - 添加适当的日志记录
+
+### 3. 提高代码模块化
+- **问题**：`focus_screen.dart` 代码较长（480行），可读性和可维护性较差
+- **优化方案**：
+  - 将长页面拆分为多个小组件
+  - 例如：TimerDisplay、DistractionButton、ControlButtons 等
+  - 提高代码的复用性和可维护性
+
+## 四、功能优化
+
+### 1. 完善通知权限管理
+- **问题**：当前通知权限请求逻辑不够完善
+- **优化方案**：
+  - 添加权限状态监听
+  - 当权限被拒绝时，引导用户手动开启权限
+  - 实现更细粒度的权限控制
+
+### 2. 增强鼓励语服务
+- **问题**：当前鼓励语服务功能比较简单
+- **优化方案**：
+  - 添加基于用户行为的个性化鼓励语
+  - 支持不同场景的鼓励语（开始、中途、完成）
+  - 允许用户添加自定义鼓励语
+
+### 3. 优化多语言支持
+- **问题**：部分硬编码字符串没有国际化
+- **优化方案**：
+  - 统一使用国际化资源
+  - 为所有用户可见的文本添加翻译
+  - 实现语言切换的即时生效
+
+## 五、测试友好性优化
+
+### 1. 提高代码可测试性
+- **问题**：当前代码结构不利于单元测试
+- **优化方案**：
+  - 提取纯函数，便于单独测试
+  - 实现接口抽象，便于 mock 测试
+  - 添加测试覆盖率报告
+
+### 2. 添加单元测试
+- **问题**：当前项目缺少单元测试
+- **优化方案**：
+  - 为核心服务添加单元测试
+  - 为数据模型添加测试
+  - 为工具函数添加测试
+
+## 六、UI/UX 优化
+
+### 1. 优化页面布局
+- **问题**：当前页面布局比较简单，缺乏层次感
+- **优化方案**：
+  - 添加更多的动画效果
+  - 优化颜色搭配和字体大小
+  - 实现响应式设计，适配不同屏幕尺寸
+
+### 2. 增强用户反馈
+- **问题**：当前用户反馈机制不够完善
+- **优化方案**：
+  - 添加更多的状态反馈（加载中、成功、失败）
+  - 优化按钮点击效果
+  - 添加声音和振动反馈（可选）
+
+## 七、实施步骤
+
+### 第一阶段：基础优化（1-2天）
+1. 统一服务层初始化模式
+2. 完善文档注释
+3. 增强错误处理
+4. 优化存储查询性能
+
+### 第二阶段：架构优化（2-3天）
+1. 引入依赖注入
+2. 提高代码模块化
+3. 优化通知服务
+4. 增强鼓励语服务
+
+### 第三阶段：功能优化（2-3天）
+1. 完善通知权限管理
+2. 优化多语言支持
+3. 增强用户反馈
+4. 优化页面布局
+
+### 第四阶段：测试优化（1-2天）
+1. 提高代码可测试性
+2. 添加单元测试
+3. 运行测试并修复问题
+
+## 八、预期收益
+
+1. **提高代码质量**：统一的架构、完善的文档、增强的错误处理
+2. **提高性能**：优化的存储查询、更高效的服务初始化
+3. **提高可维护性**：模块化的代码、清晰的依赖关系
+4. **提高可测试性**：依赖注入、单元测试
+5. **增强功能**：更完善的通知服务、个性化的鼓励语
+6. **优化用户体验**：更好的UI设计、增强的用户反馈
+
+通过以上优化，FocusBuddy 项目将变得更加健壮、高效、可维护，为后续的功能扩展和版本迭代打下坚实的基础。

CLAUDE.md

@@ -0,0 +1,284 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+FocusBuddy is a Flutter-based focus timer app designed for neurodivergent minds, implementing a "no-punishment" philosophy. The core concept is that distractions during focus sessions are tracked but don't interrupt the timer, providing a gentler approach to productivity tracking.
+
+## Commands
+
+### Development Setup
+```bash
+# Check Flutter version and environment
+flutter doctor
+
+# Get dependencies
+flutter pub get
+
+# Generate localization files (required after editing .arb files)
+flutter gen-l10n
+
+# Generate Hive adapters (required after modifying model classes)
+flutter pub run build_runner build
+
+# Clean build artifacts
+flutter clean
+```
+
+### Running the App
+```bash
+# List available devices/emulators
+flutter devices
+
+# Run on default device
+flutter run
+
+# Run on specific device
+flutter run -d <device_id>
+
+# Run on Chrome (web)
+flutter run -d chrome
+
+# Run with hot reload (default in debug mode)
+flutter run --hot
+```
+
+### Building
+```bash
+# Build APK for Android
+flutter build apk
+
+# Build App Bundle for Google Play
+flutter build appbundle
+
+# Build for iOS (requires macOS)
+flutter build ios
+
+# Build for Windows
+flutter build windows
+```
+
+### Testing & Analysis
+```bash
+# Run static analysis
+flutter analyze
+
+# Run tests
+flutter test
+
+# Check for outdated packages
+flutter pub outdated
+```
+
+## Architecture
+
+### Core Philosophy
+The app follows a **no-punishment approach** to focus tracking:
+- Timer continues running even when user reports a distraction
+- Distractions are tracked via "I got distracted" button
+- Encouragement messages replace negative feedback
+- All distraction counts are for awareness, not judgment
+
+### Key Technical Decisions
+
+**State Management**: Simple `StatefulWidget` approach (no external state management)
+- Focus session state managed locally in `FocusScreen`
+- Settings and preferences stored in `shared_preferences`
+- Historical data stored in Hive local database
+
+**Data Persistence**:
+- **Hive** for focus session history (typeId 0 for `FocusSession`)
+- **SharedPreferences** for app settings (onboarding status, default duration, locale)
+- Sessions stored with full distraction tracking but continue regardless of interruptions
+
+**Notifications**:
+- Background notifications when app is inactive during focus session
+- Uses `flutter_local_notifications` with `WidgetsBindingObserver` lifecycle tracking
+- Notification updates every 30 seconds when app is backgrounded
+
+**Internationalization (i18n)**:
+- Uses Flutter's official `intl` package with ARB files
+- 13 supported languages (en, zh, ja, ko, es, de, fr, pt, ru, hi, id, it, ar)
+- Locale can be changed at runtime without app restart via `MyApp.updateLocale()`
+- Localization files generated in `lib/l10n/` via `flutter gen-l10n`
+
+### Project Structure
+
+```
+lib/
+├── main.dart                  # Entry point, app initialization
+├── models/                    # Data models
+│   ├── focus_session.dart     # Hive model for session data
+│   ├── focus_session.g.dart   # Generated Hive adapter
+│   └── distraction_type.dart  # Enum for distraction categories
+├── screens/                   # UI screens
+│   ├── onboarding_screen.dart # First-time user guide
+│   ├── home_screen.dart       # Main screen with "Start Focus" button
+│   ├── focus_screen.dart      # Active timer + distraction button
+│   ├── complete_screen.dart   # Post-session summary
+│   ├── history_screen.dart    # Past sessions list
+│   └── settings_screen.dart   # Duration & locale settings
+├── services/                  # Business logic
+│   ├── storage_service.dart   # Hive database operations
+│   ├── encouragement_service.dart # Random message picker
+│   └── notification_service.dart  # Background notifications
+├── theme/                     # Design system
+│   ├── app_theme.dart         # Material theme config
+│   ├── app_colors.dart        # Color palette constants
+│   └── app_text_styles.dart   # Typography definitions
+└── l10n/                      # Generated localization files
+    ├── app_localizations.dart
+    └── app_localizations_*.dart
+```
+
+### Data Flow
+
+**Focus Session Lifecycle**:
+1. User selects duration in `HomeScreen` (loads from SharedPreferences)
+2. `FocusScreen` starts countdown timer with `Timer.periodic`
+3. User can tap "I got distracted" → adds to `_distractions` list, timer continues
+4. Timer completion or manual stop → `FocusSession` saved to Hive via `StorageService`
+5. `CompleteScreen` shows stats fetched from `StorageService.getTodaySessions()`
+6. `HistoryScreen` displays all sessions from `StorageService.getAllSessions()`
+
+**Critical Implementation**: The distraction button **never** pauses the timer - this is the app's core differentiator.
+
+### FocusSession Model
+
+```dart
+@HiveType(typeId: 0)
+class FocusSession {
+  DateTime startTime;
+  int durationMinutes;      // Planned (e.g., 25)
+  int actualMinutes;        // May be less if stopped early
+  int distractionCount;     // Total distractions logged
+  bool completed;           // True if timer reached zero
+  List<String> distractionTypes; // Categories selected
+}
+```
+
+### Theme System
+
+Uses Google Fonts (Nunito) with centralized design tokens:
+- **Primary Color**: `#6C63FF` (Purple)
+- **Background**: `#F5F7FA` (Light Gray)
+- **Text Primary**: `#2D3748` (Dark Gray)
+- **Success**: `#48BB78` (Green - used sparingly)
+
+All UI components reference `AppTextStyles` and `AppColors` constants - never use hardcoded values.
+
+## MVP Feature Set
+
+**Current Implementation** (as of git commit `005ad8d`):
+- ✅ Onboarding flow with "no-punishment" philosophy explanation
+- ✅ Configurable session duration (15/25/45 minutes)
+- ✅ Background notifications during active sessions
+- ✅ Distraction tracking with 4 categories
+- ✅ Today's stats on completion screen
+- ✅ History view (today's sessions only in MVP)
+- ✅ Multi-language support (13 languages)
+- ✅ Settings for duration and locale
+
+**Intentionally Deferred** (see [README.md](README.md)):
+- ⏸️ Variable duration slider (fixed presets preferred for MVP)
+- ⏸️ White noise audio playback
+- ⏸️ Weekly trend charts
+- ⏸️ PDF report export
+- ⏸️ AdMob integration (monetization post-validation)
+
+## Working with Localization
+
+### Adding/Editing Translations
+1. Translations are defined in `l10n/app_en.arb` (source locale) and other `app_*.arb` files
+2. After editing ARB files, regenerate code:
+   ```bash
+   flutter gen-l10n
+   ```
+3. Use in code:
+   ```dart
+   final l10n = AppLocalizations.of(context)!;
+   Text(l10n.appTitle);
+   ```
+
+### Adding a New Language
+1. Create `l10n/app_<locale>.arb` (copy from `app_en.arb`)
+2. Add locale to `supportedLocales` in [main.dart](lib/main.dart:97-111)
+3. Add to language picker in [settings_screen.dart](lib/screens/settings_screen.dart)
+4. Run `flutter gen-l10n`
+
+## Modifying Data Models
+
+When changing Hive models (e.g., `FocusSession`):
+1. Update model class with `@HiveField` annotations
+2. Regenerate adapters:
+   ```bash
+   flutter pub run build_runner build --delete-conflicting-outputs
+   ```
+3. Consider migration strategy if changing existing fields (current MVP has no migration logic)
+
+## Code Generation
+
+This project uses code generation for:
+- **Hive adapters**: `*.g.dart` files for model serialization
+- **Localization**: `lib/l10n/app_localizations*.dart` from ARB files
+
+Never edit generated files manually - always modify source files and regenerate.
+
+## Platform-Specific Notes
+
+### Android
+- Minimum SDK: 21 (Android 5.0)
+- Target SDK: 34 (Android 14)
+- Notification permission auto-requested on Android 13+ via `permission_handler`
+
+### iOS
+- Requires Xcode for building
+- Notification permissions requested via `DarwinInitializationSettings`
+- See [MACOS_BUILD_GUIDE.md](MACOS_BUILD_GUIDE.md) for macOS-specific instructions
+
+### Web
+- Notifications explicitly disabled on web platform (see `NotificationService._initialized`)
+- Uses responsive layout but primarily designed for mobile
+
+## Design System Guidelines
+
+When adding new UI components:
+1. Use `AppColors` constants - never hardcode colors
+2. Use `AppTextStyles` for typography - never inline text styles
+3. Border radius should be 16px for cards/buttons (consistency)
+4. Button minimum height: 56px (touch-friendly)
+5. Padding: Use multiples of 8 (8, 16, 24, 32, 48, 60)
+6. Never use red/destructive colors for distractions (core philosophy)
+
+## Testing Strategy
+
+Current implementation focuses on manual testing:
+- Test timer countdown accuracy across different durations
+- Verify background notifications appear when app is minimized
+- Test distraction button during active session (ensure timer continues)
+- Verify data persists after app restart (Hive)
+- Test locale switching without app restart
+
+## Known Constraints
+
+1. **No backend server** - All data stored locally (intentional for privacy)
+2. **No analytics** - No Firebase/Amplitude in MVP (intentional)
+3. **Single-device only** - No cross-device sync
+4. **Today-focused** - History screen shows minimal data in MVP
+
+## Important Implementation Rules
+
+1. **Never pause timer on distraction** - This would violate the core philosophy
+2. **Never show negative/punitive messaging** - Use encouragement instead
+3. **Always use localized strings** - No hardcoded English text
+4. **Always save sessions to Hive** - Even if stopped early (actualMinutes < durationMinutes)
+5. **Background notifications required** - Users need countdown visibility when multitasking
+
+## Related Documentation
+
+- [README.md](README.md) - Product optimization strategy and MVP scope
+- [ui-design-spec.md](ui-design-spec.md) - Complete UI/UX specifications
+- [mvp-launch-checklist.md](mvp-launch-checklist.md) - 4-week development roadmap
+- [product-design.md](product-design.md) - Original product vision
+- [MACOS_BUILD_GUIDE.md](MACOS_BUILD_GUIDE.md) - macOS/iOS build instructions

android/app/src/main/res/drawable/ic_notification.xml

@@ -0,0 +1,15 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24">
+    <!-- Simple timer/focus icon for notifications (white silhouette) -->
+    <!-- Circle representing focus/timer -->
+    <path
+        android:fillColor="#FFFFFFFF"
+        android:pathData="M12,2C6.48,2 2,6.48 2,12C2,17.52 6.48,22 12,22C17.52,22 22,17.52 22,12C22,6.48 17.52,2 12,2ZM12,20C7.59,20 4,16.41 4,12C4,7.59 7.59,4 12,4C16.41,4 20,7.59 20,12C20,16.41 16.41,20 12,20Z"/>
+    <!-- Clock hand pointing up (12 o'clock - focus start position) -->
+    <path
+        android:fillColor="#FFFFFFFF"
+        android:pathData="M11,7L11,12.41L14.29,15.71L15.71,14.29L13,11.59L13,7Z"/>
+</vector>

lib/components/control_buttons.dart

@@ -0,0 +1,70 @@
+import 'package:flutter/material.dart';
+import '../theme/app_colors.dart';
+
+/// Control Buttons Component
+class ControlButtons extends StatelessWidget {
+  final bool isPaused;
+  final VoidCallback onTogglePause;
+  final VoidCallback onStopEarly;
+  final String pauseText;
+  final String resumeText;
+  final String stopText;
+
+  const ControlButtons({
+    super.key,
+    required this.isPaused,
+    required this.onTogglePause,
+    required this.onStopEarly,
+    required this.pauseText,
+    required this.resumeText,
+    required this.stopText,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    return Column(
+      children: [
+        // Pause/Resume Button
+        SizedBox(
+          width: double.infinity,
+          child: OutlinedButton(
+            onPressed: onTogglePause,
+            style: OutlinedButton.styleFrom(
+              foregroundColor: AppColors.primary,
+              side: const BorderSide(color: AppColors.primary, width: 1),
+              minimumSize: const Size(double.infinity, 48),
+              shape: RoundedRectangleBorder(
+                borderRadius: BorderRadius.circular(12),
+              ),
+            ),
+            child: Row(
+              mainAxisAlignment: MainAxisAlignment.center,
+              children: [
+                Icon(isPaused ? Icons.play_arrow : Icons.pause),
+                const SizedBox(width: 8),
+                Text(isPaused ? resumeText : pauseText),
+              ],
+            ),
+          ),
+        ),
+
+        const SizedBox(height: 16),
+
+        // Stop Button
+        Padding(
+          padding: const EdgeInsets.only(bottom: 24.0),
+          child: TextButton(
+            onPressed: onStopEarly,
+            child: Text(
+              stopText,
+              style: const TextStyle(
+                color: AppColors.textSecondary,
+                fontSize: 14,
+              ),
+            ),
+          ),
+        ),
+      ],
+    );
+  }
+}

lib/components/distraction_button.dart

@@ -0,0 +1,51 @@
+import 'package:flutter/material.dart';
+import '../theme/app_colors.dart';
+
+/// Distraction Button Component
+class DistractionButton extends StatelessWidget {
+  final VoidCallback onPressed;
+  final String buttonText;
+
+  const DistractionButton({
+    super.key,
+    required this.onPressed,
+    required this.buttonText,
+  });
+
+  @override
+  Widget build(BuildContext context) {
+    return SizedBox(
+      width: double.infinity,
+      child: ElevatedButton(
+        onPressed: onPressed,
+        style: ElevatedButton.styleFrom(
+          backgroundColor: AppColors.distractionButton,
+          foregroundColor: AppColors.textPrimary,
+          minimumSize: const Size(double.infinity, 48),
+          shape: RoundedRectangleBorder(
+            borderRadius: BorderRadius.circular(12),
+          ),
+          elevation: 0,
+        ),
+        child: Row(
+          mainAxisAlignment: MainAxisAlignment.center,
+          children: [
+            Text(
+              buttonText,
+              style: const TextStyle(
+                fontFamily: 'Nunito',
+                fontSize: 18,
+                fontWeight: FontWeight.w600,
+              ),
+            ),
+            const SizedBox(width: 8),
+            const Text(
+              '🤚',
+              style: TextStyle(fontSize: 20),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}

lib/components/timer_display.dart

@@ -0,0 +1,27 @@
+import 'package:flutter/material.dart';
+import '../theme/app_text_styles.dart';
+
+/// Timer Display Component
+class TimerDisplay extends StatelessWidget {
+  final int remainingSeconds;
+
+  const TimerDisplay({
+    super.key,
+    required this.remainingSeconds,
+  });
+
+  /// Format seconds to MM:SS format
+  String _formatTime(int seconds) {
+    final minutes = seconds ~/ 60;
+    final secs = seconds % 60;
+    return '${minutes.toString().padLeft(2, '0')}:${secs.toString().padLeft(2, '0')}';
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Text(
+      _formatTime(remainingSeconds),
+      style: AppTextStyles.timerDisplay,
+    );
+  }
+}

lib/main.dart

@@ -2,9 +2,8 @@ import 'package:flutter/material.dart';
 import 'package:flutter_localizations/flutter_localizations.dart';
 import 'l10n/app_localizations.dart';
 import 'theme/app_theme.dart';
-import 'services/storage_service.dart';
+import 'services/di.dart';
 import 'services/encouragement_service.dart';
-import 'services/notification_service.dart';
 import 'screens/home_screen.dart';
 import 'screens/onboarding_screen.dart';
 import 'screens/settings_screen.dart';
@@ -12,19 +11,10 @@ import 'screens/settings_screen.dart';
 void main() async {
   WidgetsFlutterBinding.ensureInitialized();
 
-  // Initialize services
+  // Initialize dependency injection
-  await StorageService.init();
+  await initializeDI();
 
-  final encouragementService = EncouragementService();
+  runApp(MyApp(encouragementService: getIt<EncouragementService>()));
-  await encouragementService.loadMessages();
-
-  // Initialize notification service
-  final notificationService = NotificationService();
-  await notificationService.initialize();
-  // Request permissions on first launch
-  await notificationService.requestPermissions();
-
-  runApp(MyApp(encouragementService: encouragementService));
 }
 
 class MyApp extends StatefulWidget {

lib/screens/focus_screen.dart

@@ -5,9 +5,13 @@ import '../theme/app_colors.dart';
 import '../theme/app_text_styles.dart';
 import '../models/distraction_type.dart';
 import '../models/focus_session.dart';
+import '../services/di.dart';
 import '../services/storage_service.dart';
 import '../services/encouragement_service.dart';
 import '../services/notification_service.dart';
+import '../components/timer_display.dart';
+import '../components/distraction_button.dart';
+import '../components/control_buttons.dart';
 import 'complete_screen.dart';
 
 /// Focus Screen - Timer and distraction tracking
@@ -32,7 +36,8 @@ class _FocusScreenState extends State<FocusScreen> with WidgetsBindingObserver {
   final List<String> _distractions = [];
   bool _isPaused = false;
   bool _isInBackground = false;
-  final NotificationService _notificationService = NotificationService();
+  final NotificationService _notificationService = getIt<NotificationService>();
+  final StorageService _storageService = getIt<StorageService>();
 
   @override
   void initState() {
@@ -125,7 +130,7 @@ class _FocusScreenState extends State<FocusScreen> with WidgetsBindingObserver {
     // Cancel ongoing notification and show completion notification
     await _notificationService.cancelOngoingFocusNotification();
 
-    _saveFocusSession(completed: true);
+    await _saveFocusSession(completed: true);
 
     if (!mounted) return;
 
@@ -219,21 +224,24 @@ class _FocusScreenState extends State<FocusScreen> with WidgetsBindingObserver {
   }
 
   Future<void> _saveFocusSession({required bool completed}) async {
-    final actualMinutes = completed
+    try {
-        ? widget.durationMinutes
+      final actualMinutes = completed
-        : ((widget.durationMinutes * 60 - _remainingSeconds) / 60).floor();
+          ? widget.durationMinutes
+          : ((widget.durationMinutes * 60 - _remainingSeconds) / 60).floor();
 
-    final session = FocusSession(
+      final session = FocusSession(
-      startTime: _startTime,
+        startTime: _startTime,
-      durationMinutes: widget.durationMinutes,
+        durationMinutes: widget.durationMinutes,
-      actualMinutes: actualMinutes,
+        actualMinutes: actualMinutes,
-      distractionCount: _distractions.length,
+        distractionCount: _distractions.length,
-      completed: completed,
+        completed: completed,
-      distractionTypes: _distractions,
+        distractionTypes: _distractions,
-    );
+      );
 
-    final storageService = StorageService();
+      await _storageService.saveFocusSession(session);
-    await storageService.saveFocusSession(session);
+    } catch (e) {
+      // Ignore save errors silently
+    }
   }
 
   void _showDistractionSheet() {
@@ -339,30 +347,22 @@ class _FocusScreenState extends State<FocusScreen> with WidgetsBindingObserver {
   }
 
   void _recordDistraction(String? type) {
-    final l10n = AppLocalizations.of(context)!;
-
     setState(() {
       if (type != null) {
         _distractions.add(type);
       }
     });
 
-    // Show encouragement toast
+    // Show distraction-specific encouragement toast
     ScaffoldMessenger.of(context).showSnackBar(
       SnackBar(
-        content: Text(l10n.distractionEncouragement),
+        content: Text(widget.encouragementService.getRandomMessage(EncouragementType.distraction)),
         duration: const Duration(seconds: 2),
         behavior: SnackBarBehavior.floating,
       ),
     );
   }
 
-  String _formatTime(int seconds) {
-    final minutes = seconds ~/ 60;
-    final secs = seconds % 60;
-    return '${minutes.toString().padLeft(2, '0')}:${secs.toString().padLeft(2, '0')}';
-  }
-
   @override
   Widget build(BuildContext context) {
     final l10n = AppLocalizations.of(context)!;
@@ -381,73 +381,27 @@ class _FocusScreenState extends State<FocusScreen> with WidgetsBindingObserver {
                       height: MediaQuery.of(context).size.height * 0.2,
                     ),
 
-                    // Timer Display
+                    // Timer Display Component
-                    Text(
+                    TimerDisplay(remainingSeconds: _remainingSeconds),
-                      _formatTime(_remainingSeconds),
-                      style: AppTextStyles.timerDisplay,
-                    ),
 
                     const SizedBox(height: 80),
 
-                    // "I got distracted" Button
+                    // "I got distracted" Button Component
-                    SizedBox(
+                    DistractionButton(
-                      width: double.infinity,
+                      onPressed: _showDistractionSheet,
-                      child: ElevatedButton(
+                      buttonText: l10n.iGotDistracted,
-                        onPressed: _showDistractionSheet,
-                        style: ElevatedButton.styleFrom(
-                          backgroundColor: AppColors.distractionButton,
-                          foregroundColor: AppColors.textPrimary,
-                          minimumSize: const Size(double.infinity, 48),
-                          shape: RoundedRectangleBorder(
-                            borderRadius: BorderRadius.circular(12),
-                          ),
-                          elevation: 0,
-                        ),
-                        child: Row(
-                          mainAxisAlignment: MainAxisAlignment.center,
-                          children: [
-                            Text(
-                              l10n.iGotDistracted,
-                              style: const TextStyle(
-                                fontFamily: 'Nunito',
-                                fontSize: 18,
-                                fontWeight: FontWeight.w600,
-                              ),
-                            ),
-                            const SizedBox(width: 8),
-                            const Text(
-                              '🤚',
-                              style: TextStyle(fontSize: 20),
-                            ),
-                          ],
-                        ),
-                      ),
                     ),
 
                     const SizedBox(height: 16),
 
-                    // Pause Button
+                    // Control Buttons Component
-                    SizedBox(
+                    ControlButtons(
-                      width: double.infinity,
+                      isPaused: _isPaused,
-                      child: OutlinedButton(
+                      onTogglePause: _togglePause,
-                        onPressed: _togglePause,
+                      onStopEarly: _stopEarly,
-                        style: OutlinedButton.styleFrom(
+                      pauseText: l10n.pause,
-                          foregroundColor: AppColors.primary,
+                      resumeText: l10n.resume,
-                          side: const BorderSide(color: AppColors.primary, width: 1),
+                      stopText: l10n.stopSession,
-                          minimumSize: const Size(double.infinity, 48),
-                          shape: RoundedRectangleBorder(
-                            borderRadius: BorderRadius.circular(12),
-                          ),
-                        ),
-                        child: Row(
-                          mainAxisAlignment: MainAxisAlignment.center,
-                          children: [
-                            Icon(_isPaused ? Icons.play_arrow : Icons.pause),
-                            const SizedBox(width: 8),
-                            Text(_isPaused ? l10n.resume : l10n.pause),
-                          ],
-                        ),
-                      ),
                     ),
 
                     SizedBox(
@@ -457,21 +411,6 @@ class _FocusScreenState extends State<FocusScreen> with WidgetsBindingObserver {
                 ),
               ),
             ),
-
-            // Stop Button (text button at bottom)
-            Padding(
-              padding: const EdgeInsets.only(bottom: 24.0),
-              child: TextButton(
-                onPressed: _stopEarly,
-                child: Text(
-                  l10n.stopSession,
-                  style: const TextStyle(
-                    color: AppColors.textSecondary,
-                    fontSize: 14,
-                  ),
-                ),
-              ),
-            ),
           ],
         ),
       ),

lib/screens/home_screen.dart

@@ -30,10 +30,17 @@ class _HomeScreenState extends State<HomeScreen> {
   }
 
   Future<void> _loadDefaultDuration() async {
-    final duration = await SettingsScreen.getDefaultDuration();
+    try {
-    setState(() {
+      final duration = await SettingsScreen.getDefaultDuration();
-      _defaultDuration = duration;
+      setState(() {
-    });
+        _defaultDuration = duration;
+      });
+    } catch (e) {
+      // Use default duration if loading fails
+      setState(() {
+        _defaultDuration = 25;
+      });
+    }
   }
 
   @override

lib/screens/settings_screen.dart

@@ -11,20 +11,34 @@ class SettingsScreen extends StatefulWidget {
 
   /// Get the saved default duration (for use in other screens)
   static Future<int> getDefaultDuration() async {
-    final prefs = await SharedPreferences.getInstance();
+    try {
-    return prefs.getInt(_durationKey) ?? 25;
+      final prefs = await SharedPreferences.getInstance();
+      return prefs.getInt(_durationKey) ?? 25;
+    } catch (e) {
+      // Return default duration if loading fails
+      return 25;
+    }
   }
 
   /// Get the saved locale
   static Future<String?> getSavedLocale() async {
-    final prefs = await SharedPreferences.getInstance();
+    try {
-    return prefs.getString(_localeKey);
+      final prefs = await SharedPreferences.getInstance();
+      return prefs.getString(_localeKey);
+    } catch (e) {
+      // Return null if loading fails
+      return null;
+    }
   }
 
   /// Save the locale
   static Future<void> saveLocale(String localeCode) async {
-    final prefs = await SharedPreferences.getInstance();
+    try {
-    await prefs.setString(_localeKey, localeCode);
+      final prefs = await SharedPreferences.getInstance();
+      await prefs.setString(_localeKey, localeCode);
+    } catch (e) {
+      // Ignore save errors
+    }
   }
 
   static const String _durationKey = 'default_duration';
@@ -48,36 +62,58 @@ class _SettingsScreenState extends State<SettingsScreen> {
   }
 
   Future<void> _loadSavedDuration() async {
-    final prefs = await SharedPreferences.getInstance();
+    try {
-    setState(() {
+      final prefs = await SharedPreferences.getInstance();
-      _selectedDuration = prefs.getInt(SettingsScreen._durationKey) ?? 25;
+      setState(() {
-    });
+        _selectedDuration = prefs.getInt(SettingsScreen._durationKey) ?? 25;
+      });
+    } catch (e) {
+      // Use default duration if loading fails
+      setState(() {
+        _selectedDuration = 25;
+      });
+    }
   }
 
   Future<void> _loadSavedLocale() async {
-    final prefs = await SharedPreferences.getInstance();
+    try {
-    setState(() {
+      final prefs = await SharedPreferences.getInstance();
-      _selectedLocale = prefs.getString(SettingsScreen._localeKey) ?? 'en';
+      setState(() {
-    });
+        _selectedLocale = prefs.getString(SettingsScreen._localeKey) ?? 'en';
+      });
+    } catch (e) {
+      // Use default locale if loading fails
+      setState(() {
+        _selectedLocale = 'en';
+      });
+    }
   }
 
   Future<void> _saveDuration(int duration) async {
-    final prefs = await SharedPreferences.getInstance();
+    try {
-    await prefs.setInt(SettingsScreen._durationKey, duration);
+      final prefs = await SharedPreferences.getInstance();
-    setState(() {
+      await prefs.setInt(SettingsScreen._durationKey, duration);
-      _selectedDuration = duration;
+      setState(() {
-    });
+        _selectedDuration = duration;
+      });
+    } catch (e) {
+      // Ignore save errors, state will be reset on next load
+    }
   }
 
   Future<void> _saveLocale(String localeCode) async {
-    await SettingsScreen.saveLocale(localeCode);
+    try {
-    setState(() {
+      await SettingsScreen.saveLocale(localeCode);
-      _selectedLocale = localeCode;
+      setState(() {
-    });
+        _selectedLocale = localeCode;
+      });
 
-    // Update locale immediately without restart
+      // Update locale immediately without restart
-    if (!mounted) return;
+      if (!mounted) return;
-    MyApp.updateLocale(context, localeCode);
+      MyApp.updateLocale(context, localeCode);
+    } catch (e) {
+      // Ignore save errors
+    }
   }
 
   @override

lib/services/di.dart

@@ -0,0 +1,51 @@
+import 'package:get_it/get_it.dart';
+import 'package:flutter/foundation.dart';
+
+import 'storage_service.dart';
+import 'notification_service.dart';
+import 'encouragement_service.dart';
+
+/// GetIt instance for dependency injection
+final getIt = GetIt.instance;
+
+/// Initialize dependency injection
+Future<void> initializeDI() async {
+  try {
+    // Register services as singletons
+    getIt.registerSingletonAsync<StorageService>(() async {
+      final service = StorageService();
+      await service.init();
+      return service;
+    });
+
+    getIt.registerSingletonAsync<NotificationService>(() async {
+      final service = NotificationService();
+      await service.initialize();
+      await service.requestPermissions();
+      return service;
+    });
+
+    getIt.registerSingletonAsync<EncouragementService>(() async {
+      final service = EncouragementService();
+      await service.loadMessages();
+      return service;
+    });
+
+    // Wait for all services to be initialized
+    await getIt.allReady();
+
+    if (kDebugMode) {
+      print('Dependency injection initialized successfully');
+    }
+  } catch (e) {
+    if (kDebugMode) {
+      print('Failed to initialize dependency injection: $e');
+    }
+    rethrow;
+  }
+}
+
+/// Reset dependency injection (for testing)
+void resetDI() {
+  getIt.reset();
+}

lib/services/encouragement_service.dart

@@ -2,9 +2,26 @@ import 'dart:convert';
 import 'dart:math';
 import 'package:flutter/services.dart';
 
-/// Service to manage encouragement messages
+/// Enum representing different encouragement message types
+enum EncouragementType {
+  general,       // General encouragement messages
+  start,         // When starting a focus session
+  distraction,   // When user gets distracted
+  complete,      // When completing a focus session
+  earlyStop,     // When stopping early
+}
+
+/// Service to manage encouragement messages for different scenarios
 class EncouragementService {
-  List<String> _messages = [];
+  // Map of encouragement types to their messages
+  final Map<EncouragementType, List<String>> _messages = {
+    EncouragementType.general: [],
+    EncouragementType.start: [],
+    EncouragementType.distraction: [],
+    EncouragementType.complete: [],
+    EncouragementType.earlyStop: [],
+  };
+  
   final Random _random = Random();
 
   /// Load encouragement messages from assets
@@ -12,28 +29,127 @@ class EncouragementService {
     try {
       final String jsonString = 
           await rootBundle.loadString('assets/encouragements.json');
-      final List<dynamic> jsonList = json.decode(jsonString);
+      final dynamic jsonData = json.decode(jsonString);
-      _messages = jsonList.cast<String>();
+      
+      // Check if the JSON is a map (new format with categories)
+      if (jsonData is Map<String, dynamic>) {
+        // Load categorized messages
+        _loadCategorizedMessages(jsonData);
+      } else if (jsonData is List<dynamic>) {
+        // Load legacy format (list of general messages)
+        _messages[EncouragementType.general] = jsonData.cast<String>();
+        // Initialize other categories with default messages
+        _initializeDefaultMessages();
+      } else {
+        // Invalid format, use defaults
+        _initializeDefaultMessages();
+      }
     } catch (e) {
-      // Fallback messages if file can't be loaded
+      // Fallback to default messages if file can't be loaded
-      _messages = [
+      _initializeDefaultMessages();
-        "Showing up is half the battle.",
-        "Every minute counts.",
-        "You're learning, not failing.",
-        "Gentleness is strength.",
-        "Progress over perfection.",
-      ];
     }
   }
   
-  /// Get a random encouragement message
+  /// Load categorized messages from JSON map
-  String getRandomMessage() {
+  void _loadCategorizedMessages(Map<String, dynamic> jsonData) {
-    if (_messages.isEmpty) {
+    // Load general messages
+    if (jsonData.containsKey('general') && jsonData['general'] is List) {
+      _messages[EncouragementType.general] = (jsonData['general'] as List).cast<String>();
+    }
+    
+    // Load start messages
+    if (jsonData.containsKey('start') && jsonData['start'] is List) {
+      _messages[EncouragementType.start] = (jsonData['start'] as List).cast<String>();
+    }
+    
+    // Load distraction messages
+    if (jsonData.containsKey('distraction') && jsonData['distraction'] is List) {
+      _messages[EncouragementType.distraction] = (jsonData['distraction'] as List).cast<String>();
+    }
+    
+    // Load complete messages
+    if (jsonData.containsKey('complete') && jsonData['complete'] is List) {
+      _messages[EncouragementType.complete] = (jsonData['complete'] as List).cast<String>();
+    }
+    
+    // Load early stop messages
+    if (jsonData.containsKey('earlyStop') && jsonData['earlyStop'] is List) {
+      _messages[EncouragementType.earlyStop] = (jsonData['earlyStop'] as List).cast<String>();
+    }
+    
+    // Ensure all categories have at least some messages
+    _ensureAllCategoriesHaveMessages();
+  }
+  
+  /// Initialize default messages for all categories
+  void _initializeDefaultMessages() {
+    _messages[EncouragementType.general] = [
+      "Showing up is half the battle.",
+      "Every minute counts.",
+      "You're learning, not failing.",
+      "Gentleness is strength.",
+      "Progress over perfection.",
+    ];
+    
+    _messages[EncouragementType.start] = [
+      "You've got this! Let's begin.",
+      "Ready to focus? Let's do this.",
+      "Every moment is a fresh start.",
+      "Let's make this session count.",
+      "You're already making progress by showing up.",
+    ];
+    
+    _messages[EncouragementType.distraction] = [
+      "It's okay to get distracted. Let's gently come back.",
+      "No guilt here! Let's try again.",
+      "Distractions happen to everyone. Let's refocus.",
+      "You're doing great by noticing and coming back.",
+      "Gentle reminder: you can always start again.",
+    ];
+    
+    _messages[EncouragementType.complete] = [
+      "🎉 Congratulations! You did it!",
+      "Great job completing your focus session!",
+      "You should be proud of yourself!",
+      "That was amazing! Well done.",
+      "You're making wonderful progress!",
+    ];
+    
+    _messages[EncouragementType.earlyStop] = [
+      "It's okay to stop early. You tried, and that's what matters.",
+      "Every effort counts, even if it's shorter than planned.",
+      "You did your best, and that's enough.",
+      "Rest when you need to. We'll be here when you're ready.",
+      "Progress, not perfection. You're doing great.",
+    ];
+  }
+  
+  /// Ensure all categories have at least some messages
+  void _ensureAllCategoriesHaveMessages() {
+    // If any category is empty, use general messages as fallback
+    for (final type in EncouragementType.values) {
+      if (_messages[type]?.isEmpty ?? true) {
+        _messages[type] = List.from(_messages[EncouragementType.general]!);
+      }
+    }
+  }
+
+  /// Get a random encouragement message for a specific type
+  String getRandomMessage([EncouragementType type = EncouragementType.general]) {
+    final messages = _messages[type] ?? [];
+    if (messages.isEmpty) {
       return "You're doing great!";
     }
-    return _messages[_random.nextInt(_messages.length)];
+    return messages[_random.nextInt(messages.length)];
   }
 
-  /// Get all messages (for testing)
+  /// Get all messages for a specific type (for testing)
-  List<String> getAllMessages() => List.from(_messages);
+  List<String> getAllMessages([EncouragementType type = EncouragementType.general]) {
+    return List.from(_messages[type] ?? []);
+  }
+  
+  /// Get all messages for all types (for testing)
+  Map<EncouragementType, List<String>> getAllMessagesByType() {
+    return Map.from(_messages);
+  }
 }

lib/services/notification_service.dart

@@ -1,3 +1,4 @@
+import 'dart:async';
 import 'package:flutter_local_notifications/flutter_local_notifications.dart';
 import 'package:flutter/foundation.dart';
 import 'package:permission_handler/permission_handler.dart';
@@ -14,6 +15,17 @@ class NotificationService {
 
   bool _initialized = false;
   
+  /// Stream controller for permission status changes
+  final StreamController<bool> _permissionStatusController = StreamController<bool>.broadcast();
+  
+  /// Get the permission status stream
+  Stream<bool> get permissionStatusStream => _permissionStatusController.stream;
+  
+  /// Dispose the stream controller
+  void dispose() {
+    _permissionStatusController.close();
+  }
+
   /// Initialize notification service
   Future<void> initialize() async {
     if (_initialized) return;
@@ -28,7 +40,9 @@ class NotificationService {
 
     try {
       // Android initialization settings
-      const androidSettings = AndroidInitializationSettings('@mipmap/ic_launcher');
+      const androidSettings = AndroidInitializationSettings(
+        '@drawable/ic_notification',
+      );
 
       // iOS initialization settings
       const iosSettings = DarwinInitializationSettings(
@@ -48,6 +62,13 @@ class NotificationService {
       );
 
       _initialized = true;
+      
+      // Start listening for permission changes
+      await listenForPermissionChanges();
+      
+      // Check initial permission status
+      await hasPermission();
+      
       if (kDebugMode) {
         print('Notification service initialized successfully');
       }
@@ -63,7 +84,6 @@ class NotificationService {
     if (kDebugMode) {
       print('Notification tapped: ${response.payload}');
     }
-    // TODO: Navigate to appropriate screen if needed
   }
 
   /// Request notification permissions (iOS and Android 13+)
@@ -71,39 +91,43 @@ class NotificationService {
     if (kIsWeb) return false;
 
     try {
+      bool isGranted = false;
+      
       // Check if we're on Android or iOS
       if (Platform.isAndroid) {
         // Android 13+ requires runtime permission
         final status = await Permission.notification.request();
+        isGranted = status.isGranted;
 
         if (kDebugMode) {
           print('Android notification permission status: $status');
         }
-
-        return status.isGranted;
       } else if (Platform.isIOS) {
         // iOS permission request
-        final result = await _notifications
+        final iosImplementation = _notifications.resolvePlatformSpecificImplementation<IOSFlutterLocalNotificationsPlugin>();
-            .resolvePlatformSpecificImplementation<
+        if (iosImplementation != null) {
-                IOSFlutterLocalNotificationsPlugin>()
+          final result = await iosImplementation.requestPermissions(alert: true, badge: true, sound: true);
-            ?.requestPermissions(
+          isGranted = result ?? false;
-              alert: true,
-              badge: true,
-              sound: true,
-            );
           
-        if (kDebugMode) {
+          if (kDebugMode) {
-          print('iOS notification permission result: $result');
+            print('iOS notification permission result: $result');
+          }
+        } else {
+          isGranted = true; // Assume granted if we can't request
         }
-
+      } else {
-        return result ?? false;
+        isGranted = true; // Assume granted for other platforms
       }
       
-      return true; // Other platforms
+      // Update the permission status stream
+      _permissionStatusController.add(isGranted);
+      
+      return isGranted;
     } catch (e) {
       if (kDebugMode) {
         print('Failed to request permissions: $e');
       }
+      _permissionStatusController.add(false);
       return false;
     }
   }
@@ -113,22 +137,40 @@ class NotificationService {
     if (kIsWeb) return false;
 
     try {
+      bool isGranted = false;
+      
       if (Platform.isAndroid) {
         final status = await Permission.notification.status;
-        return status.isGranted;
+        isGranted = status.isGranted;
       } else if (Platform.isIOS) {
-        // For iOS, we can't easily check without requesting, so we assume granted after request
+        // For iOS, we assume granted after initial request
-        return true;
+        isGranted = true;
+      } else {
+        isGranted = true; // Assume granted for other platforms
       }
-      return true;
+      
+      // Update the permission status stream
+      _permissionStatusController.add(isGranted);
+      
+      return isGranted;
     } catch (e) {
       if (kDebugMode) {
         print('Failed to check permission status: $e');
       }
+      _permissionStatusController.add(false);
       return false;
     }
   }
   
+  /// Listen for permission status changes
+  Future<void> listenForPermissionChanges() async {
+    // Permission status changes listening is not supported in current permission_handler version
+    // This method is kept for future implementation
+    if (kDebugMode) {
+      print('Permission status changes listening is not supported');
+    }
+  }
+
   /// Show focus session completed notification
   Future<void> showFocusCompletedNotification({
     required int minutes,
@@ -147,6 +189,7 @@ class NotificationService {
         priority: Priority.high,
         enableVibration: true,
         playSound: true,
+        icon: '@drawable/ic_notification',
       );
 
       const iosDetails = DarwinNotificationDetails(
@@ -162,7 +205,8 @@ class NotificationService {
 
       // Use provided title/body or fall back to English
       final notificationTitle = title ?? '🎉 Focus session complete!';
-      final notificationBody = body ??
+      final notificationBody =
+          body ??
           (distractionCount == 0
               ? 'You focused for $minutes ${minutes == 1 ? 'minute' : 'minutes'} without distractions!'
               : 'You focused for $minutes ${minutes == 1 ? 'minute' : 'minutes'}. Great effort!');
@@ -186,9 +230,7 @@ class NotificationService {
   }
 
   /// Show reminder notification (optional feature for future)
-  Future<void> showReminderNotification({
+  Future<void> showReminderNotification({required String message}) async {
-    required String message,
-  }) async {
     if (kIsWeb || !_initialized) return;
 
     try {
@@ -198,6 +240,7 @@ class NotificationService {
         channelDescription: 'Gentle reminders to focus',
         importance: Importance.defaultImportance,
         priority: Priority.defaultPriority,
+        icon: '@drawable/ic_notification',
       );
 
       const iosDetails = DarwinNotificationDetails();
@@ -259,7 +302,8 @@ class NotificationService {
 
     try {
       // Format time display for fallback
-      final timeStr = '${remainingMinutes.toString().padLeft(2, '0')}:${(remainingSeconds % 60).toString().padLeft(2, '0')}';
+      final timeStr =
+          '${remainingMinutes.toString().padLeft(2, '0')}:${(remainingSeconds % 60).toString().padLeft(2, '0')}';
 
       const androidDetails = AndroidNotificationDetails(
         'focus_timer',
@@ -274,6 +318,7 @@ class NotificationService {
         playSound: false,
         // Show in status bar
         showProgress: false,
+        icon: '@drawable/ic_notification',
       );
 
       const iosDetails = DarwinNotificationDetails(

lib/services/service_locator.dart

@@ -0,0 +1,77 @@
+import 'package:flutter/foundation.dart';
+
+import 'storage_service.dart';
+import 'notification_service.dart';
+import 'encouragement_service.dart';
+
+/// Service Locator - 统一管理所有服务实例
+class ServiceLocator {
+  static final ServiceLocator _instance = ServiceLocator._internal();
+  factory ServiceLocator() => _instance;
+  ServiceLocator._internal();
+
+  late StorageService _storageService;
+  late NotificationService _notificationService;
+  late EncouragementService _encouragementService;
+  bool _isInitialized = false;
+
+  /// 初始化所有服务
+  Future<void> initialize() async {
+    if (_isInitialized) return;
+
+    try {
+      // 初始化存储服务
+      _storageService = StorageService();
+      await _storageService.init();
+
+      // 初始化通知服务
+      _notificationService = NotificationService();
+      await _notificationService.initialize();
+      await _notificationService.requestPermissions();
+
+      // 初始化鼓励语服务
+      _encouragementService = EncouragementService();
+      await _encouragementService.loadMessages();
+
+      _isInitialized = true;
+      if (kDebugMode) {
+        print('ServiceLocator initialized successfully');
+      }
+    } catch (e) {
+      if (kDebugMode) {
+        print('Failed to initialize ServiceLocator: $e');
+      }
+      rethrow;
+    }
+  }
+
+  /// 获取存储服务实例
+  StorageService get storageService {
+    _checkInitialized();
+    return _storageService;
+  }
+
+  /// 获取通知服务实例
+  NotificationService get notificationService {
+    _checkInitialized();
+    return _notificationService;
+  }
+
+  /// 获取鼓励语服务实例
+  EncouragementService get encouragementService {
+    _checkInitialized();
+    return _encouragementService;
+  }
+
+  /// 检查服务是否已初始化
+  void _checkInitialized() {
+    if (!_isInitialized) {
+      throw Exception('ServiceLocator has not been initialized yet. Call initialize() first.');
+    }
+  }
+
+  /// 重置服务（用于测试）
+  void reset() {
+    _isInitialized = false;
+  }
+}

lib/services/storage_service.dart

@@ -1,62 +1,135 @@
 import 'package:hive_flutter/hive_flutter.dart';
+import 'package:flutter/foundation.dart';
 import '../models/focus_session.dart';
 
 /// Service to manage local storage using Hive
 class StorageService {
   static const String _focusSessionBox = 'focus_sessions';
   
-  /// Initialize Hive
+  // Cache for today's sessions to improve performance
-  static Future<void> init() async {
+  List<FocusSession>? _todaySessionsCache;
-    await Hive.initFlutter();
+  DateTime? _cacheDate;
 
-    // Register adapters
+  /// Initialize Hive storage service
-    Hive.registerAdapter(FocusSessionAdapter());
+  /// 
+  /// This method initializes Hive, registers adapters, and opens the focus sessions box.
+  /// It should be called once during app initialization.
+  Future<void> init() async {
+    try {
+      await Hive.initFlutter();
 
-    // Open boxes
+      // Register adapters
-    await Hive.openBox<FocusSession>(_focusSessionBox);
+      Hive.registerAdapter(FocusSessionAdapter());
+
+      // Open boxes
+      await Hive.openBox<FocusSession>(_focusSessionBox);
+      
+      if (kDebugMode) {
+        print('StorageService initialized successfully');
+      }
+    } catch (e) {
+      if (kDebugMode) {
+        print('Failed to initialize StorageService: $e');
+      }
+      rethrow;
+    }
   }
 
   /// Get the focus sessions box
   Box<FocusSession> get _sessionsBox => Hive.box<FocusSession>(_focusSessionBox);
   
-  /// Save a focus session
+  /// Invalidate the cache when data changes
+  void _invalidateCache() {
+    _todaySessionsCache = null;
+    _cacheDate = null;
+  }
+
+  /// Save a focus session to local storage
+  /// 
+  /// [session] - The focus session to save
+  /// Returns a Future that completes when the session is saved
   Future<void> saveFocusSession(FocusSession session) async {
-    await _sessionsBox.add(session);
+    try {
+      await _sessionsBox.add(session);
+      _invalidateCache(); // Invalidate cache when data changes
+    } catch (e) {
+      if (kDebugMode) {
+        print('Failed to save focus session: $e');
+      }
+      rethrow;
+    }
   }
 
-  /// Get all focus sessions
+  /// Get all focus sessions from local storage
+  /// 
+  /// Returns a list of all focus sessions stored locally
   List<FocusSession> getAllSessions() {
-    return _sessionsBox.values.toList();
+    try {
+      return _sessionsBox.values.toList();
+    } catch (e) {
+      if (kDebugMode) {
+        print('Failed to get all sessions: $e');
+      }
+      return [];
+    }
   }
 
-  /// Get today's focus sessions
+  /// Get today's focus sessions with caching
+  /// 
+  /// Returns a list of focus sessions that occurred today
+  /// Uses caching to improve performance for frequent calls
   List<FocusSession> getTodaySessions() {
-    final now = DateTime.now();
+    try {
-    final today = DateTime(now.year, now.month, now.day);
+      final now = DateTime.now();
+      final today = DateTime(now.year, now.month, now.day);
 
-    return _sessionsBox.values.where((session) {
+      // Check if cache is valid
-      final sessionDate = DateTime(
+      if (_todaySessionsCache != null && _cacheDate == today) {
-        session.startTime.year,
+        return _todaySessionsCache!;
-        session.startTime.month,
+      }
-        session.startTime.day,
+
-      );
+      // Query and cache results
-      return sessionDate == today;
+      final sessions = _sessionsBox.values.where((session) {
-    }).toList();
+        final sessionDate = DateTime(
+          session.startTime.year,
+          session.startTime.month,
+          session.startTime.day,
+        );
+        return sessionDate == today;
+      }).toList();
+
+      // Update cache
+      _todaySessionsCache = sessions;
+      _cacheDate = today;
+      
+      return sessions;
+    } catch (e) {
+      if (kDebugMode) {
+        print('Failed to get today\'s sessions: $e');
+      }
+      return [];
+    }
   }
 
   /// Get total focus minutes for today
+  /// 
+  /// Returns the sum of actual minutes focused today
   int getTodayTotalMinutes() {
     return getTodaySessions()
         .fold<int>(0, (sum, session) => sum + session.actualMinutes);
   }
 
   /// Get total distractions for today
+  /// 
+  /// Returns the total number of distractions recorded today
   int getTodayDistractionCount() {
     return getTodaySessions()
         .fold<int>(0, (sum, session) => sum + session.distractionCount);
   }
 
   /// Get total completed sessions for today
+  /// 
+  /// Returns the number of focus sessions completed today
   int getTodayCompletedCount() {
     return getTodaySessions()
         .where((session) => session.completed)
@@ -64,22 +137,54 @@ class StorageService {
   }
 
   /// Get total sessions count for today (including stopped early)
+  /// 
+  /// Returns the total number of focus sessions started today
   int getTodaySessionsCount() {
     return getTodaySessions().length;
   }
 
-  /// Delete a focus session
+  /// Delete a focus session from local storage
+  /// 
+  /// [session] - The focus session to delete
+  /// Returns a Future that completes when the session is deleted
   Future<void> deleteSession(FocusSession session) async {
-    await session.delete();
+    try {
+      await session.delete();
+      _invalidateCache(); // Invalidate cache when data changes
+    } catch (e) {
+      if (kDebugMode) {
+        print('Failed to delete focus session: $e');
+      }
+      rethrow;
+    }
   }
 
-  /// Clear all sessions (for testing/debugging)
+  /// Clear all sessions from local storage (for testing/debugging)
+  /// 
+  /// Returns a Future that completes when all sessions are cleared
   Future<void> clearAllSessions() async {
-    await _sessionsBox.clear();
+    try {
+      await _sessionsBox.clear();
+      _invalidateCache(); // Invalidate cache when data changes
+    } catch (e) {
+      if (kDebugMode) {
+        print('Failed to clear all sessions: $e');
+      }
+      rethrow;
+    }
   }
 
-  /// Close all boxes
+  /// Close all Hive boxes
+  /// 
+  /// Should be called when the app is closing to properly clean up resources
   static Future<void> close() async {
-    await Hive.close();
+    try {
+      await Hive.close();
+    } catch (e) {
+      if (kDebugMode) {
+        print('Failed to close Hive boxes: $e');
+      }
+      rethrow;
+    }
   }
 }

pubspec.lock

@@ -277,6 +277,14 @@ packages:
       url: "https://pub.flutter-io.cn"
     source: hosted
     version: "4.0.0"
+  get_it:
+    dependency: "direct main"
+    description:
+      name: get_it
+      sha256: d85128a5dae4ea777324730dc65edd9c9f43155c109d5cc0a69cab74139fbac1
+      url: "https://pub.flutter-io.cn"
+    source: hosted
+    version: "7.7.0"
   glob:
     dependency: transitive
     description:

pubspec.yaml

@@ -46,6 +46,7 @@ dependencies:
   shared_preferences: ^2.2.0            # Simple key-value storage (for onboarding)
   intl: ^0.20.2                         # Date formatting and i18n
   google_fonts: ^6.1.0                  # Google Fonts (Nunito)
+  get_it: ^7.7.0                        # Dependency injection framework
 
 dev_dependencies:
   flutter_test:

test/encouragement_service_test.dart

@@ -0,0 +1,79 @@
+import 'package:flutter_test/flutter_test.dart';
+import 'package:focus_buddy/services/encouragement_service.dart';
+
+void main() {
+  group('EncouragementService', () {
+    late EncouragementService encouragementService;
+
+    setUp(() {
+      encouragementService = EncouragementService();
+    });
+
+    test('should initialize with default messages when load fails', () async {
+      // Act: Try to load messages (will fail since we're in test environment)
+      await encouragementService.loadMessages();
+
+      // Assert: Should have default messages for all types
+      expect(encouragementService.getAllMessages(), isNotEmpty);
+      expect(encouragementService.getAllMessages(EncouragementType.start), isNotEmpty);
+      expect(encouragementService.getAllMessages(EncouragementType.distraction), isNotEmpty);
+      expect(encouragementService.getAllMessages(EncouragementType.complete), isNotEmpty);
+      expect(encouragementService.getAllMessages(EncouragementType.earlyStop), isNotEmpty);
+    });
+
+    test('should return a random message for each type', () async {
+      // Arrange: Load messages
+      await encouragementService.loadMessages();
+
+      // Act: Get random messages for each type
+      final generalMessage = encouragementService.getRandomMessage();
+      final startMessage = encouragementService.getRandomMessage(EncouragementType.start);
+      final distractionMessage = encouragementService.getRandomMessage(EncouragementType.distraction);
+      final completeMessage = encouragementService.getRandomMessage(EncouragementType.complete);
+      final earlyStopMessage = encouragementService.getRandomMessage(EncouragementType.earlyStop);
+
+      // Assert: All messages should be non-empty strings
+      expect(generalMessage, isNotEmpty);
+      expect(startMessage, isNotEmpty);
+      expect(distractionMessage, isNotEmpty);
+      expect(completeMessage, isNotEmpty);
+      expect(earlyStopMessage, isNotEmpty);
+    });
+
+    test('should return general messages when using default type', () async {
+      // Arrange: Load messages
+      await encouragementService.loadMessages();
+      final generalMessages = encouragementService.getAllMessages();
+
+      // Act: Get a random message with default type
+      final message = encouragementService.getRandomMessage();
+
+      // Assert: Message should be in the general messages list
+      expect(generalMessages, contains(message));
+    });
+
+    test('should return distraction-specific messages when requested', () async {
+      // Arrange: Load messages
+      await encouragementService.loadMessages();
+      final distractionMessages = encouragementService.getAllMessages(EncouragementType.distraction);
+
+      // Act: Get a random distraction message
+      final message = encouragementService.getRandomMessage(EncouragementType.distraction);
+
+      // Assert: Message should be in the distraction messages list
+      expect(distractionMessages, contains(message));
+    });
+
+    test('should return complete-specific messages when requested', () async {
+      // Arrange: Load messages
+      await encouragementService.loadMessages();
+      final completeMessages = encouragementService.getAllMessages(EncouragementType.complete);
+
+      // Act: Get a random complete message
+      final message = encouragementService.getRandomMessage(EncouragementType.complete);
+
+      // Assert: Message should be in the complete messages list
+      expect(completeMessages, contains(message));
+    });
+  });
+}