积分、成就系统

lib/services/points_service.dart

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+import 'dart:math';
+import '../models/focus_session.dart';
+import '../models/user_progress.dart';
+
+/// Service for calculating and managing points
+class PointsService {
+  /// Calculate points earned from a focus session
+  /// Returns a map with breakdown: {basePoints, honestyBonus, total, breakdown}
+  Map<String, dynamic> calculateSessionPoints(FocusSession session) {
+    // Base points = actual minutes focused
+    int basePoints = session.actualMinutes;
+
+    // Honesty bonus: reward for recording distractions (with cap to prevent abuse)
+    int honestyBonus = _calculateHonestyBonus(
+      session.distractionCount,
+      session.actualMinutes,
+    );
+
+    int total = basePoints + honestyBonus;
+
+    // Detailed breakdown for UI display
+    List<Map<String, dynamic>> breakdown = [
+      {
+        'label': '专注时长',
+        'value': basePoints,
+        'description': '每专注1分钟获得1积分',
+      },
+      {
+        'label': '诚实奖励',
+        'value': honestyBonus,
+        'description': '记录分心情况获得额外积分',
+      },
+    ];
+
+    return {
+      'basePoints': basePoints,
+      'honestyBonus': honestyBonus,
+      'total': total,
+      'breakdown': breakdown,
+    };
+  }
+
+  /// Calculate honesty bonus with anti-abuse cap
+  /// Strategy: Max 1 rewarded distraction per 10 minutes
+  int _calculateHonestyBonus(int distractionCount, int minutes) {
+    if (distractionCount == 0) return 0;
+
+    // Cap: 1 rewarded distraction per 10 minutes
+    // 15 min → max 2 distractions
+    // 25 min → max 3 distractions
+    // 45 min → max 5 distractions
+    int maxBonusDistraction = max(1, (minutes / 10).ceil());
+    int rewardedCount = min(distractionCount, maxBonusDistraction);
+
+    return rewardedCount; // 1 point per recorded distraction (up to cap)
+  }
+
+  /// Process daily check-in and return points earned with detailed breakdown
+  Map<String, dynamic> processCheckIn(UserProgress progress) {
+    final now = DateTime.now();
+
+    // Base check-in points
+    int points = 5;
+    List<Map<String, dynamic>> breakdown = [
+      {
+        'label': '每日签到',
+        'value': 5,
+        'description': '每日首次签到获得基础积分',
+      },
+    ];
+
+    // Update check-in streak
+    if (_isConsecutiveDay(progress.lastCheckInDate, now)) {
+      progress.consecutiveCheckIns++;
+      
+      // Bonus for streak milestones
+      if (progress.consecutiveCheckIns % 7 == 0) {
+        int weeklyBonus = 30;
+        points += weeklyBonus;
+        breakdown.add({
+          'label': '连续签到奖励',
+          'value': weeklyBonus,
+          'description': '连续签到${progress.consecutiveCheckIns}天',
+        });
+      } else if (progress.consecutiveCheckIns % 30 == 0) {
+        int monthlyBonus = 100;
+        points += monthlyBonus;
+        breakdown.add({
+          'label': '连续签到奖励',
+          'value': monthlyBonus,
+          'description': '连续签到${progress.consecutiveCheckIns}天',
+        });
+      }
+    } else {
+      progress.consecutiveCheckIns = 1;
+    }
+
+    // Update last check-in date
+    progress.lastCheckInDate = now;
+
+    // Add to check-in history (store date only, not time)
+    final dateOnly = DateTime(now.year, now.month, now.day);
+    if (!progress.checkInHistory.any((date) =>
+        date.year == dateOnly.year &&
+        date.month == dateOnly.month &&
+        date.day == dateOnly.day)) {
+      progress.checkInHistory.add(dateOnly);
+    }
+
+    return {
+      'points': points,
+      'consecutiveDays': progress.consecutiveCheckIns,
+      'breakdown': breakdown,
+    };
+  }
+
+  /// Check if two dates are consecutive days
+  bool _isConsecutiveDay(DateTime? lastDate, DateTime currentDate) {
+    if (lastDate == null) return false;
+
+    final lastDateOnly = DateTime(lastDate.year, lastDate.month, lastDate.day);
+    final currentDateOnly =
+        DateTime(currentDate.year, currentDate.month, currentDate.day);
+
+    final diff = currentDateOnly.difference(lastDateOnly).inDays;
+    return diff == 1;
+  }
+
+  /// Calculate level based on total points
+  Map<String, dynamic> calculateLevel(int totalPoints) {
+    // Simple level calculation: each level requires 100 points
+    int level = (totalPoints / 100).floor() + 1;
+    int pointsForCurrentLevel = (level - 1) * 100;
+    int pointsForNextLevel = level * 100;
+    int pointsInCurrentLevel = totalPoints - pointsForCurrentLevel;
+    double progress = pointsInCurrentLevel / 100;
+
+    return {
+      'level': level,
+      'pointsForCurrentLevel': pointsForCurrentLevel,
+      'pointsForNextLevel': pointsForNextLevel,
+      'pointsInCurrentLevel': pointsInCurrentLevel,
+      'progress': progress,
+    };
+  }
+
+  /// Get points balance summary
+  Map<String, dynamic> getPointsSummary(UserProgress progress) {
+    final levelInfo = calculateLevel(progress.totalPoints);
+    
+    return {
+      'currentPoints': progress.currentPoints,
+      'totalPoints': progress.totalPoints,
+      'level': levelInfo['level'],
+      'levelProgress': levelInfo['progress'],
+      'consecutiveCheckIns': progress.consecutiveCheckIns,
+      'totalCheckIns': progress.checkInHistory.length,
+    };
+  }
+}