fix(analytics): use activity end time for achievement earnedAt #24

Signed-off-by: Marcus Fihlon <marcus@fihlon.swiss>

src/main/java/net/javahippie/fitpub/repository/ActivityRepository.java

@@ -31,6 +31,14 @@ public interface ActivityRepository extends JpaRepository<Activity, UUID> {
      */
     List<Activity> findByUserIdOrderByStartedAtDesc(UUID userId);
 
+    /**
+     * Find all activities for a specific user in chronological order.
+     *
+     * @param userId the user ID
+     * @return list of activities
+     */
+    List<Activity> findByUserIdOrderByStartedAtAsc(UUID userId);
+
     /**
      * Find all activities for a user within a date range.
      *

src/main/java/net/javahippie/fitpub/service/AchievementService.java

@@ -43,11 +43,13 @@ public class AchievementService {
     public List<Achievement> checkAndAwardAchievements(Activity activity) {
         List<Achievement> newAchievements = new ArrayList<>();
 
-        if (activity.getUserId() == null) {
+        if (activity.getUserId() == null || activity.getStartedAt() == null || activity.getEndedAt() == null) {
             return newAchievements;
         }
 
         UUID userId = activity.getUserId();
+        List<Activity> activityHistory = activityRepository.findByUserIdOrderByStartedAtAsc(userId);
+        ActivityProgress progress = ActivityProgress.fromHistory(activityHistory, activity);
 
         // Load all of the user's existing achievement types in a single query so the
         // sub-checks below can do an in-memory `contains()` instead of an EXISTS query
@@ -58,28 +60,28 @@ public class AchievementService {
         }
 
         // Check first activity achievements
-        newAchievements.addAll(checkFirstActivityAchievements(userId, activity, existing));
+        newAchievements.addAll(checkFirstActivityAchievements(userId, activity, progress, existing));
 
         // Check distance milestones
-        newAchievements.addAll(checkDistanceMilestones(userId, existing));
+        newAchievements.addAll(checkDistanceMilestones(userId, activity, progress, existing));
 
         // Check activity count milestones
-        newAchievements.addAll(checkActivityCountMilestones(userId, existing));
+        newAchievements.addAll(checkActivityCountMilestones(userId, activity, progress, existing));
 
         // Check streak achievements
-        newAchievements.addAll(checkStreakAchievements(userId, existing));
+        newAchievements.addAll(checkStreakAchievements(userId, activity, progress, existing));
 
         // Check time-based achievements
-        newAchievements.addAll(checkTimeBasedAchievements(userId, activity, existing));
+        newAchievements.addAll(checkTimeBasedAchievements(userId, activity, progress, existing));
 
         // Check elevation achievements
-        newAchievements.addAll(checkElevationAchievements(userId, activity, existing));
+        newAchievements.addAll(checkElevationAchievements(userId, activity, progress, existing));
 
         // Check variety achievements
-        newAchievements.addAll(checkVarietyAchievements(userId, existing));
+        newAchievements.addAll(checkVarietyAchievements(userId, activity, progress, existing));
 
         // Check speed achievements
-        newAchievements.addAll(checkSpeedAchievements(userId, activity, existing));
+        newAchievements.addAll(checkSpeedAchievements(userId, activity, progress, existing));
 
         return newAchievements;
     }
@@ -88,12 +90,14 @@ public class AchievementService {
      * Check first activity achievements.
      */
     private List<Achievement> checkFirstActivityAchievements(UUID userId, Activity activity,
+                                                             ActivityProgress progress,
                                                              Set<Achievement.AchievementType> existing) {
         List<Achievement> achievements = new ArrayList<>();
 
         // First activity overall
-        long totalActivities = activityRepository.countByUserId(userId);
+        if (progress.previousActivityCount() == 0 &&
-        if (totalActivities == 1 && !existing.contains(Achievement.AchievementType.FIRST_ACTIVITY)) {
+            progress.currentActivityCount() == 1 &&
+            !existing.contains(Achievement.AchievementType.FIRST_ACTIVITY)) {
             achievements.add(awardAchievement(
                     userId,
                     Achievement.AchievementType.FIRST_ACTIVITY,
@@ -102,15 +106,17 @@ public class AchievementService {
                     "🎉",
                     "#ff00ff",
                     activity.getId(),
+                    activity.getEndedAt(),
                     null
             ));
         }
 
         // First activity by type
         String activityType = activity.getActivityType().name();
-        long typeCount = activityRepository.countByUserIdAndActivityType(userId, activity.getActivityType());
+        long previousTypeCount = progress.previousActivityTypeCount(activity.getActivityType());
+        long currentTypeCount = progress.currentActivityTypeCount(activity.getActivityType());
 
-        if (typeCount == 1) {
+        if (previousTypeCount == 0 && currentTypeCount == 1) {
             Achievement.AchievementType achievementType = switch (activityType) {
                 case "RUN" -> Achievement.AchievementType.FIRST_RUN;
                 case "RIDE" -> Achievement.AchievementType.FIRST_RIDE;
@@ -127,6 +133,7 @@ public class AchievementService {
                         getActivityEmoji(activityType),
                         "#00ffff",
                         activity.getId(),
+                        activity.getEndedAt(),
                         null
                 ));
             }
@@ -138,16 +145,13 @@ public class AchievementService {
     /**
      * Check distance milestone achievements.
      */
-    private List<Achievement> checkDistanceMilestones(UUID userId, Set<Achievement.AchievementType> existing) {
+    private List<Achievement> checkDistanceMilestones(UUID userId, Activity activity,
+                                                      ActivityProgress progress,
+                                                      Set<Achievement.AchievementType> existing) {
         List<Achievement> achievements = new ArrayList<>();
 
-        // Calculate total distance
+        double previousKm = progress.previousDistanceMeters().doubleValue() / 1000.0;
-        BigDecimal totalDistance = activityRepository.sumDistanceByUserId(userId);
+        double currentKm = progress.currentDistanceMeters().doubleValue() / 1000.0;
-        if (totalDistance == null) {
-            return achievements;
-        }
-
-        double totalKm = totalDistance.doubleValue() / 1000.0;
 
         // Check milestones
         Map<Double, Achievement.AchievementType> milestones = Map.of(
@@ -159,7 +163,9 @@ public class AchievementService {
         );
 
         for (Map.Entry<Double, Achievement.AchievementType> entry : milestones.entrySet()) {
-            if (totalKm >= entry.getKey() && !existing.contains(entry.getValue())) {
+            if (previousKm < entry.getKey() &&
+                currentKm >= entry.getKey() &&
+                !existing.contains(entry.getValue())) {
                 achievements.add(awardAchievement(
                         userId,
                         entry.getValue(),
@@ -167,7 +173,8 @@ public class AchievementService {
                         String.format("Reached %.0f kilometers total distance!", entry.getKey()),
                         "🏃",
                         "#ffff00",
-                        null,
+                        activity.getId(),
+                        activity.getEndedAt(),
                         Map.of("distance_km", entry.getKey())
                 ));
             }
@@ -179,11 +186,11 @@ public class AchievementService {
     /**
      * Check activity count milestone achievements.
      */
-    private List<Achievement> checkActivityCountMilestones(UUID userId, Set<Achievement.AchievementType> existing) {
+    private List<Achievement> checkActivityCountMilestones(UUID userId, Activity activity,
+                                                           ActivityProgress progress,
+                                                           Set<Achievement.AchievementType> existing) {
         List<Achievement> achievements = new ArrayList<>();
 
-        long activityCount = activityRepository.countByUserId(userId);
-
         Map<Long, Achievement.AchievementType> milestones = Map.of(
                 10L, Achievement.AchievementType.ACTIVITIES_10,
                 50L, Achievement.AchievementType.ACTIVITIES_50,
@@ -193,7 +200,9 @@ public class AchievementService {
         );
 
         for (Map.Entry<Long, Achievement.AchievementType> entry : milestones.entrySet()) {
-            if (activityCount >= entry.getKey() && !existing.contains(entry.getValue())) {
+            if (progress.previousActivityCount() < entry.getKey() &&
+                progress.currentActivityCount() >= entry.getKey() &&
+                !existing.contains(entry.getValue())) {
                 achievements.add(awardAchievement(
                         userId,
                         entry.getValue(),
@@ -201,7 +210,8 @@ public class AchievementService {
                         String.format("Completed %d activities!", entry.getKey()),
                         "💪",
                         "#ff6600",
-                        null,
+                        activity.getId(),
+                        activity.getEndedAt(),
                         Map.of("activity_count", entry.getKey())
                 ));
             }
@@ -213,10 +223,13 @@ public class AchievementService {
     /**
      * Check streak achievements (consecutive days).
      */
-    private List<Achievement> checkStreakAchievements(UUID userId, Set<Achievement.AchievementType> existing) {
+    private List<Achievement> checkStreakAchievements(UUID userId, Activity activity,
+                                                      ActivityProgress progress,
+                                                      Set<Achievement.AchievementType> existing) {
         List<Achievement> achievements = new ArrayList<>();
 
-        int currentStreak = calculateCurrentStreak(userId);
+        int previousStreak = calculateStreak(progress.previousActivityDates(), activity.getEndedAt().toLocalDate());
+        int currentStreak = calculateStreak(progress.currentActivityDates(), activity.getEndedAt().toLocalDate());
 
         Map<Integer, Achievement.AchievementType> streakMilestones = Map.of(
                 7, Achievement.AchievementType.STREAK_7_DAYS,
@@ -226,7 +239,9 @@ public class AchievementService {
         );
 
         for (Map.Entry<Integer, Achievement.AchievementType> entry : streakMilestones.entrySet()) {
-            if (currentStreak >= entry.getKey() && !existing.contains(entry.getValue())) {
+            if (previousStreak < entry.getKey() &&
+                currentStreak >= entry.getKey() &&
+                !existing.contains(entry.getValue())) {
                 achievements.add(awardAchievement(
                         userId,
                         entry.getValue(),
@@ -234,7 +249,8 @@ public class AchievementService {
                         String.format("Worked out %d days in a row!", entry.getKey()),
                         "🔥",
                         "#ff1493",
-                        null,
+                        activity.getId(),
+                        activity.getEndedAt(),
                         Map.of("streak_days", entry.getKey())
                 ));
             }
@@ -247,6 +263,7 @@ public class AchievementService {
      * Check time-based achievements (early bird, night owl, weekend warrior).
      */
     private List<Achievement> checkTimeBasedAchievements(UUID userId, Activity activity,
+                                                         ActivityProgress progress,
                                                          Set<Achievement.AchievementType> existing) {
         List<Achievement> achievements = new ArrayList<>();
 
@@ -254,8 +271,9 @@ public class AchievementService {
 
         // Early bird (before 6am)
         if (startTime.isBefore(LocalTime.of(6, 0)) && !existing.contains(Achievement.AchievementType.EARLY_BIRD)) {
-            long earlyActivities = activityRepository.countByUserIdAndStartTimeBefore(userId, LocalTime.of(6, 0));
+            long previousEarlyActivities = progress.previousActivitiesStartingBefore(LocalTime.of(6, 0));
-            if (earlyActivities >= 5) {
+            long currentEarlyActivities = progress.currentActivitiesStartingBefore(LocalTime.of(6, 0));
+            if (previousEarlyActivities < 5 && currentEarlyActivities >= 5) {
                 achievements.add(awardAchievement(
                         userId,
                         Achievement.AchievementType.EARLY_BIRD,
@@ -264,15 +282,17 @@ public class AchievementService {
                         "🌅",
                         "#ccff00",
                         activity.getId(),
-                        Map.of("early_activities", earlyActivities)
+                        activity.getEndedAt(),
+                        Map.of("early_activities", currentEarlyActivities)
                 ));
             }
         }
 
         // Night owl (after 10pm)
         if (startTime.isAfter(LocalTime.of(22, 0)) && !existing.contains(Achievement.AchievementType.NIGHT_OWL)) {
-            long lateActivities = activityRepository.countByUserIdAndStartTimeAfter(userId, LocalTime.of(22, 0));
+            long previousLateActivities = progress.previousActivitiesStartingAfter(LocalTime.of(22, 0));
-            if (lateActivities >= 5) {
+            long currentLateActivities = progress.currentActivitiesStartingAfter(LocalTime.of(22, 0));
+            if (previousLateActivities < 5 && currentLateActivities >= 5) {
                 achievements.add(awardAchievement(
                         userId,
                         Achievement.AchievementType.NIGHT_OWL,
@@ -281,7 +301,8 @@ public class AchievementService {
                         "🦉",
                         "#9370db",
                         activity.getId(),
-                        Map.of("late_activities", lateActivities)
+                        activity.getEndedAt(),
+                        Map.of("late_activities", currentLateActivities)
                 ));
             }
         }
@@ -293,12 +314,14 @@ public class AchievementService {
      * Check elevation achievements.
      */
     private List<Achievement> checkElevationAchievements(UUID userId, Activity activity,
+                                                         ActivityProgress progress,
                                                          Set<Achievement.AchievementType> existing) {
         List<Achievement> achievements = new ArrayList<>();
 
         // Single activity elevation
         if (activity.getElevationGain() != null &&
             activity.getElevationGain().compareTo(BigDecimal.valueOf(1000)) >= 0 &&
+            !progress.previousHasElevationGainAtLeast(BigDecimal.valueOf(1000)) &&
             !existing.contains(Achievement.AchievementType.MOUNTAINEER_1000M)) {
 
             achievements.add(awardAchievement(
@@ -309,16 +332,18 @@ public class AchievementService {
                     "⛰️",
                     "#8b4513",
                     activity.getId(),
+                    activity.getEndedAt(),
                     Map.of("elevation_gain", activity.getElevationGain())
             ));
         }
 
         // Total elevation milestones
-        BigDecimal totalElevation = activityRepository.sumElevationGainByUserId(userId);
+        double previousElevation = progress.previousElevationMeters().doubleValue();
-        if (totalElevation != null) {
+        double currentElevation = progress.currentElevationMeters().doubleValue();
-            double totalM = totalElevation.doubleValue();
 
-            if (totalM >= 5000 && !existing.contains(Achievement.AchievementType.MOUNTAINEER_5000M)) {
+        if (previousElevation < 5000 &&
+            currentElevation >= 5000 &&
+            !existing.contains(Achievement.AchievementType.MOUNTAINEER_5000M)) {
             achievements.add(awardAchievement(
                     userId,
                     Achievement.AchievementType.MOUNTAINEER_5000M,
@@ -326,12 +351,15 @@ public class AchievementService {
                     "Climbed 5000m total elevation!",
                     "🏔️",
                     "#4169e1",
-                        null,
+                    activity.getId(),
-                        Map.of("total_elevation", totalM)
+                    activity.getEndedAt(),
+                    Map.of("total_elevation", currentElevation)
             ));
         }
 
-            if (totalM >= 10000 && !existing.contains(Achievement.AchievementType.MOUNTAINEER_10000M)) {
+        if (previousElevation < 10000 &&
+            currentElevation >= 10000 &&
+            !existing.contains(Achievement.AchievementType.MOUNTAINEER_10000M)) {
             achievements.add(awardAchievement(
                     userId,
                     Achievement.AchievementType.MOUNTAINEER_10000M,
@@ -339,11 +367,11 @@ public class AchievementService {
                     "Climbed 10000m total elevation!",
                     "🗻",
                     "#1e90ff",
-                        null,
+                    activity.getId(),
-                        Map.of("total_elevation", totalM)
+                    activity.getEndedAt(),
+                    Map.of("total_elevation", currentElevation)
             ));
         }
-        }
 
         return achievements;
     }
@@ -351,12 +379,17 @@ public class AchievementService {
     /**
      * Check variety achievements.
      */
-    private List<Achievement> checkVarietyAchievements(UUID userId, Set<Achievement.AchievementType> existing) {
+    private List<Achievement> checkVarietyAchievements(UUID userId, Activity activity,
+                                                       ActivityProgress progress,
+                                                       Set<Achievement.AchievementType> existing) {
         List<Achievement> achievements = new ArrayList<>();
 
-        long distinctActivityTypes = activityRepository.countDistinctActivityTypesByUserId(userId);
+        long previousDistinctActivityTypes = progress.previousDistinctActivityTypes();
+        long currentDistinctActivityTypes = progress.currentDistinctActivityTypes();
 
-        if (distinctActivityTypes >= 3 && !existing.contains(Achievement.AchievementType.VARIETY_SEEKER)) {
+        if (previousDistinctActivityTypes < 3 &&
+            currentDistinctActivityTypes >= 3 &&
+            !existing.contains(Achievement.AchievementType.VARIETY_SEEKER)) {
             achievements.add(awardAchievement(
                     userId,
                     Achievement.AchievementType.VARIETY_SEEKER,
@@ -364,8 +397,9 @@ public class AchievementService {
                     "Tried 3+ different activity types!",
                     "🌈",
                     "#ff69b4",
-                    null,
+                    activity.getId(),
-                    Map.of("activity_types", distinctActivityTypes)
+                    activity.getEndedAt(),
+                    Map.of("activity_types", currentDistinctActivityTypes)
             ));
         }
 
@@ -376,6 +410,7 @@ public class AchievementService {
      * Check speed achievements.
      */
     private List<Achievement> checkSpeedAchievements(UUID userId, Activity activity,
+                                                     ActivityProgress progress,
                                                      Set<Achievement.AchievementType> existing) {
         List<Achievement> achievements = new ArrayList<>();
 
@@ -383,7 +418,9 @@ public class AchievementService {
             // maxSpeed is already in km/h from FitParser
             double maxSpeedKmh = activity.getMetrics().getMaxSpeed().doubleValue();
 
-            if (maxSpeedKmh >= 40 && !existing.contains(Achievement.AchievementType.SPEED_DEMON)) {
+            if (maxSpeedKmh >= 40 &&
+                !progress.previousHasMaxSpeedAtLeast(BigDecimal.valueOf(40)) &&
+                !existing.contains(Achievement.AchievementType.SPEED_DEMON)) {
                 achievements.add(awardAchievement(
                         userId,
                         Achievement.AchievementType.SPEED_DEMON,
@@ -392,6 +429,7 @@ public class AchievementService {
                         "⚡",
                         "#ffd700",
                         activity.getId(),
+                        activity.getEndedAt(),
                         Map.of("max_speed_kmh", maxSpeedKmh)
                 ));
             }
@@ -400,70 +438,13 @@ public class AchievementService {
         return achievements;
     }
 
-    /**
-     * Calculate current activity streak (consecutive days).
-     *
-     * <p>Loads all activity timestamps for the user in the last 366 days in a single
-     * query, deduplicates them to a {@code Set<LocalDate>} in Java, and walks the
-     * resulting set in memory. Previously this method issued one {@code SELECT EXISTS}
-     * query per day (up to 365 round-trips per activity upload), which was the single
-     * biggest performance hot spot in the achievement evaluation path.
-     *
-     * <p>Java-side date deduplication is intentional: Hibernate 6 + Spring Data 3 do
-     * not reliably convert SQL date scalar projections to {@code List<LocalDate>}.
-     * The result set is small (a few hundred timestamps at most) so the cost of
-     * Java-side distinct is negligible.
-     *
-     * <p>The streak / rest-day logic is preserved bug-for-bug from the previous
-     * implementation: a missing day after a streak has started is silently skipped
-     * (the original loop did the same). Fixing the rest-day semantics is out of
-     * scope for this performance change.
-     */
-    private int calculateCurrentStreak(UUID userId) {
-        LocalDate today = LocalDate.now();
-        // 366 to safely cover the lookback window even if today's activity is in the
-        // future relative to the cutoff (timezone edge cases).
-        LocalDateTime since = today.minusDays(366).atStartOfDay();
-        Set<LocalDate> activityDates = new HashSet<>();
-        for (LocalDateTime ts : activityRepository.findActivityStartTimestampsSince(userId, since)) {
-            activityDates.add(ts.toLocalDate());
-        }
-
-        if (activityDates.isEmpty()) {
-            return 0;
-        }
-
-        LocalDate checkDate = today;
-        int streak = 0;
-
-        // Walk backwards from today using the in-memory set instead of per-day queries.
-        for (int i = 0; i < 365; i++) {
-            boolean hasActivity = activityDates.contains(checkDate);
-
-            if (hasActivity) {
-                streak++;
-                checkDate = checkDate.minusDays(1);
-            } else {
-                // Allow one rest day if we already have a streak (preserving original
-                // behaviour, including the latent "infinite consecutive rest days
-                // allowed once a streak has started" quirk in the original loop).
-                if (streak > 0 && i > 0) {
-                    checkDate = checkDate.minusDays(1);
-                    continue;
-                }
-                break;
-            }
-        }
-
-        return streak;
-    }
-
     /**
      * Award an achievement to a user.
      */
     private Achievement awardAchievement(UUID userId, Achievement.AchievementType achievementType,
                                         String name, String description, String icon, String color,
-                                        UUID activityId, Map<String, Object> metadata) {
+                                        UUID activityId, LocalDateTime earnedAt,
+                                        Map<String, Object> metadata) {
         Achievement achievement = Achievement.builder()
                 .userId(userId)
                 .achievementType(achievementType)
@@ -471,7 +452,7 @@ public class AchievementService {
                 .description(description)
                 .badgeIcon(icon)
                 .badgeColor(color)
-                .earnedAt(LocalDateTime.now())
+                .earnedAt(earnedAt != null ? earnedAt : LocalDateTime.now())
                 .activityId(activityId)
                 .metadata(metadata)
                 .build();
@@ -510,4 +491,170 @@ public class AchievementService {
     public long getAchievementCount(UUID userId) {
         return achievementRepository.countByUserId(userId);
     }
+
+    private int calculateStreak(Set<LocalDate> activityDates, LocalDate anchorDate) {
+        if (activityDates.isEmpty() || !activityDates.contains(anchorDate)) {
+            return 0;
+        }
+
+        LocalDate checkDate = anchorDate;
+        int streak = 0;
+
+        for (int i = 0; i < 365; i++) {
+            boolean hasActivity = activityDates.contains(checkDate);
+
+            if (hasActivity) {
+                streak++;
+                checkDate = checkDate.minusDays(1);
+            } else {
+                if (streak > 0 && i > 0) {
+                    checkDate = checkDate.minusDays(1);
+                    continue;
+                }
+                break;
+            }
+        }
+
+        return streak;
+    }
+
+    private record ActivityProgress(
+            List<Activity> previousActivities,
+            List<Activity> currentActivities
+    ) {
+        private static ActivityProgress fromHistory(List<Activity> activityHistory, Activity currentActivity) {
+            int currentIndex = -1;
+            for (int i = 0; i < activityHistory.size(); i++) {
+                if (Objects.equals(activityHistory.get(i).getId(), currentActivity.getId())) {
+                    currentIndex = i;
+                    break;
+                }
+            }
+
+            if (currentIndex < 0) {
+                throw new IllegalStateException("Current activity missing from chronological history: " + currentActivity.getId());
+            }
+
+            return new ActivityProgress(
+                    List.copyOf(activityHistory.subList(0, currentIndex)),
+                    List.copyOf(activityHistory.subList(0, currentIndex + 1))
+            );
+        }
+
+        long previousActivityCount() {
+            return previousActivities.size();
+        }
+
+        long currentActivityCount() {
+            return currentActivities.size();
+        }
+
+        long previousActivityTypeCount(Activity.ActivityType type) {
+            return previousActivities.stream().filter(activity -> activity.getActivityType() == type).count();
+        }
+
+        long currentActivityTypeCount(Activity.ActivityType type) {
+            return currentActivities.stream().filter(activity -> activity.getActivityType() == type).count();
+        }
+
+        BigDecimal previousDistanceMeters() {
+            return sumDistance(previousActivities);
+        }
+
+        BigDecimal currentDistanceMeters() {
+            return sumDistance(currentActivities);
+        }
+
+        BigDecimal previousElevationMeters() {
+            return sumElevation(previousActivities);
+        }
+
+        BigDecimal currentElevationMeters() {
+            return sumElevation(currentActivities);
+        }
+
+        boolean previousHasElevationGainAtLeast(BigDecimal threshold) {
+            return previousActivities.stream()
+                    .map(Activity::getElevationGain)
+                    .filter(Objects::nonNull)
+                    .anyMatch(elevation -> elevation.compareTo(threshold) >= 0);
+        }
+
+        long previousDistinctActivityTypes() {
+            return previousActivities.stream().map(Activity::getActivityType).distinct().count();
+        }
+
+        long currentDistinctActivityTypes() {
+            return currentActivities.stream().map(Activity::getActivityType).distinct().count();
+        }
+
+        long previousActivitiesStartingBefore(LocalTime time) {
+            return previousActivities.stream()
+                    .filter(activity -> activity.getStartedAt() != null)
+                    .filter(activity -> activity.getStartedAt().toLocalTime().isBefore(time))
+                    .count();
+        }
+
+        long currentActivitiesStartingBefore(LocalTime time) {
+            return currentActivities.stream()
+                    .filter(activity -> activity.getStartedAt() != null)
+                    .filter(activity -> activity.getStartedAt().toLocalTime().isBefore(time))
+                    .count();
+        }
+
+        long previousActivitiesStartingAfter(LocalTime time) {
+            return previousActivities.stream()
+                    .filter(activity -> activity.getStartedAt() != null)
+                    .filter(activity -> activity.getStartedAt().toLocalTime().isAfter(time))
+                    .count();
+        }
+
+        long currentActivitiesStartingAfter(LocalTime time) {
+            return currentActivities.stream()
+                    .filter(activity -> activity.getStartedAt() != null)
+                    .filter(activity -> activity.getStartedAt().toLocalTime().isAfter(time))
+                    .count();
+        }
+
+        Set<LocalDate> previousActivityDates() {
+            return collectDates(previousActivities);
+        }
+
+        Set<LocalDate> currentActivityDates() {
+            return collectDates(currentActivities);
+        }
+
+        boolean previousHasMaxSpeedAtLeast(BigDecimal thresholdKmh) {
+            return previousActivities.stream()
+                    .map(Activity::getMetrics)
+                    .filter(Objects::nonNull)
+                    .map(metrics -> metrics.getMaxSpeed())
+                    .filter(Objects::nonNull)
+                    .anyMatch(speed -> speed.compareTo(thresholdKmh) >= 0);
+        }
+
+        private static BigDecimal sumDistance(List<Activity> activities) {
+            return activities.stream()
+                    .map(Activity::getTotalDistance)
+                    .filter(Objects::nonNull)
+                    .reduce(BigDecimal.ZERO, BigDecimal::add);
+        }
+
+        private static BigDecimal sumElevation(List<Activity> activities) {
+            return activities.stream()
+                    .map(Activity::getElevationGain)
+                    .filter(Objects::nonNull)
+                    .reduce(BigDecimal.ZERO, BigDecimal::add);
+        }
+
+        private static Set<LocalDate> collectDates(List<Activity> activities) {
+            Set<LocalDate> dates = new HashSet<>();
+            for (Activity activity : activities) {
+                if (activity.getStartedAt() != null) {
+                    dates.add(activity.getStartedAt().toLocalDate());
+                }
+            }
+            return dates;
+        }
+    }
 }

src/test/java/net/javahippie/fitpub/service/AchievementServiceTest.java

@@ -14,14 +14,14 @@ import net.javahippie.fitpub.repository.AchievementRepository;
 import net.javahippie.fitpub.repository.ActivityRepository;
 
 import java.math.BigDecimal;
+import java.time.LocalDate;
 import java.time.LocalDateTime;
-import java.time.LocalTime;
+import java.util.ArrayList;
 import java.util.List;
 import java.util.UUID;
 
 import static org.junit.jupiter.api.Assertions.*;
 import static org.mockito.ArgumentMatchers.any;
-import static org.mockito.ArgumentMatchers.eq;
 import static org.mockito.Mockito.*;
 
 /**
@@ -54,14 +54,7 @@ class AchievementServiceTest {
     void testCheckAndAwardAchievements_FirstActivity() {
         // Given
         Activity activity = createActivity(Activity.ActivityType.RUN, 5000L, BigDecimal.ZERO);
-
+        stubHistory(activity);
-        when(activityRepository.countByUserId(userId)).thenReturn(1L);
-        when(activityRepository.countByUserIdAndActivityType(userId, Activity.ActivityType.RUN)).thenReturn(1L);
-        when(activityRepository.sumDistanceByUserId(userId)).thenReturn(BigDecimal.valueOf(5000));
-        when(activityRepository.countDistinctActivityTypesByUserId(userId)).thenReturn(1L);
-        // Streak source: today has one activity (1-day streak — not enough to trigger any streak achievement)
-        lenient().when(activityRepository.findActivityStartTimestampsSince(any(), any()))
-            .thenReturn(List.of(java.time.LocalDateTime.now()));
         when(achievementRepository.save(any(Achievement.class))).thenAnswer(invocation -> invocation.getArgument(0));
 
         // When
@@ -82,12 +75,11 @@ class AchievementServiceTest {
     @DisplayName("Should award first run achievement")
     void testCheckAndAwardAchievements_FirstRun() {
         // Given
+        Activity firstRide = createActivity(Activity.ActivityType.RIDE, 10000L, BigDecimal.ZERO);
+        firstRide.setStartedAt(testTime.minusDays(1));
         Activity activity = createActivity(Activity.ActivityType.RUN, 5000L, BigDecimal.ZERO);
 
-        when(activityRepository.countByUserId(userId)).thenReturn(10L); // Not first overall
+        stubHistory(firstRide, activity);
-        when(activityRepository.countByUserIdAndActivityType(userId, Activity.ActivityType.RUN)).thenReturn(1L);
-        when(activityRepository.sumDistanceByUserId(userId)).thenReturn(BigDecimal.valueOf(50000));
-        when(activityRepository.countDistinctActivityTypesByUserId(userId)).thenReturn(2L);
         when(achievementRepository.save(any(Achievement.class))).thenAnswer(invocation -> invocation.getArgument(0));
 
         // When
@@ -102,13 +94,12 @@ class AchievementServiceTest {
     @Test
     @DisplayName("Should award distance milestone achievements")
     void testCheckAndAwardAchievements_DistanceMilestone() {
-        // Given - User has completed 10+ km total
+        // Given - Current activity crosses 10 km total
+        Activity previous = createActivity(Activity.ActivityType.RUN, 7000L, BigDecimal.ZERO);
+        previous.setStartedAt(testTime.minusDays(1));
         Activity activity = createActivity(Activity.ActivityType.RUN, 5000L, BigDecimal.ZERO);
 
-        when(activityRepository.countByUserId(userId)).thenReturn(5L);
+        stubHistory(previous, activity);
-        when(activityRepository.countByUserIdAndActivityType(any(), any())).thenReturn(3L);
-        when(activityRepository.sumDistanceByUserId(userId)).thenReturn(BigDecimal.valueOf(12000)); // 12 km
-        when(activityRepository.countDistinctActivityTypesByUserId(userId)).thenReturn(1L);
         when(achievementRepository.save(any(Achievement.class))).thenAnswer(invocation -> invocation.getArgument(0));
 
         // When
@@ -126,13 +117,17 @@ class AchievementServiceTest {
     @Test
     @DisplayName("Should award activity count milestone")
     void testCheckAndAwardAchievements_ActivityCount() {
-        // Given - User has 10 activities
+        // Given - Current activity is the 10th activity
+        List<Activity> history = new ArrayList<>();
+        for (int i = 0; i < 9; i++) {
+            Activity previous = createActivity(Activity.ActivityType.RUN, 5000L, BigDecimal.ZERO);
+            previous.setStartedAt(testTime.minusDays(10 - i));
+            history.add(previous);
+        }
         Activity activity = createActivity(Activity.ActivityType.RUN, 5000L, BigDecimal.ZERO);
+        history.add(activity);
 
-        when(activityRepository.countByUserId(userId)).thenReturn(10L);
+        stubHistory(history);
-        when(activityRepository.countByUserIdAndActivityType(any(), any())).thenReturn(5L);
-        when(activityRepository.sumDistanceByUserId(userId)).thenReturn(BigDecimal.valueOf(50000));
-        when(activityRepository.countDistinctActivityTypesByUserId(userId)).thenReturn(1L);
         when(achievementRepository.save(any(Achievement.class))).thenAnswer(invocation -> invocation.getArgument(0));
 
         // When
@@ -147,15 +142,18 @@ class AchievementServiceTest {
     @Test
     @DisplayName("Should award early bird achievement")
     void testCheckAndAwardAchievements_EarlyBird() {
-        // Given - Activity before 6am, and user has 5+ early activities
+        // Given - Activity before 6am is the 5th early activity
+        List<Activity> history = new ArrayList<>();
+        for (int i = 0; i < 4; i++) {
+            Activity previous = createActivity(Activity.ActivityType.RUN, 5000L, BigDecimal.ZERO);
+            previous.setStartedAt(LocalDateTime.of(2025, 11, 20 + i, 5, 30));
+            history.add(previous);
+        }
         Activity activity = createActivity(Activity.ActivityType.RUN, 5000L, BigDecimal.ZERO);
         activity.setStartedAt(LocalDateTime.of(2025, 12, 1, 5, 30)); // 5:30 AM
 
-        when(activityRepository.countByUserId(userId)).thenReturn(10L);
+        history.add(activity);
-        when(activityRepository.countByUserIdAndActivityType(any(), any())).thenReturn(5L);
+        stubHistory(history);
-        when(activityRepository.sumDistanceByUserId(userId)).thenReturn(BigDecimal.valueOf(50000));
-        when(activityRepository.countDistinctActivityTypesByUserId(userId)).thenReturn(1L);
-        when(activityRepository.countByUserIdAndStartTimeBefore(eq(userId), eq(LocalTime.of(6, 0)))).thenReturn(5L);
         when(achievementRepository.save(any(Achievement.class))).thenAnswer(invocation -> invocation.getArgument(0));
 
         // When
@@ -170,15 +168,18 @@ class AchievementServiceTest {
     @Test
     @DisplayName("Should award night owl achievement")
     void testCheckAndAwardAchievements_NightOwl() {
-        // Given - Activity after 10pm, and user has 5+ late activities
+        // Given - Activity after 10pm is the 5th late activity
+        List<Activity> history = new ArrayList<>();
+        for (int i = 0; i < 4; i++) {
+            Activity previous = createActivity(Activity.ActivityType.RUN, 5000L, BigDecimal.ZERO);
+            previous.setStartedAt(LocalDateTime.of(2025, 11, 20 + i, 23, 0));
+            history.add(previous);
+        }
         Activity activity = createActivity(Activity.ActivityType.RUN, 5000L, BigDecimal.ZERO);
         activity.setStartedAt(LocalDateTime.of(2025, 12, 1, 23, 0)); // 11:00 PM
 
-        when(activityRepository.countByUserId(userId)).thenReturn(10L);
+        history.add(activity);
-        when(activityRepository.countByUserIdAndActivityType(any(), any())).thenReturn(5L);
+        stubHistory(history);
-        when(activityRepository.sumDistanceByUserId(userId)).thenReturn(BigDecimal.valueOf(50000));
-        when(activityRepository.countDistinctActivityTypesByUserId(userId)).thenReturn(1L);
-        when(activityRepository.countByUserIdAndStartTimeAfter(eq(userId), eq(LocalTime.of(22, 0)))).thenReturn(5L);
         when(achievementRepository.save(any(Achievement.class))).thenAnswer(invocation -> invocation.getArgument(0));
 
         // When
@@ -196,11 +197,7 @@ class AchievementServiceTest {
         // Given - Activity with 1000m+ elevation gain
         Activity activity = createActivity(Activity.ActivityType.HIKE, 10000L, BigDecimal.valueOf(1200));
 
-        when(activityRepository.countByUserId(userId)).thenReturn(5L);
+        stubHistory(activity);
-        when(activityRepository.countByUserIdAndActivityType(any(), any())).thenReturn(3L);
-        when(activityRepository.sumDistanceByUserId(userId)).thenReturn(BigDecimal.valueOf(50000));
-        when(activityRepository.sumElevationGainByUserId(userId)).thenReturn(BigDecimal.valueOf(1200));
-        when(activityRepository.countDistinctActivityTypesByUserId(userId)).thenReturn(1L);
         when(achievementRepository.save(any(Achievement.class))).thenAnswer(invocation -> invocation.getArgument(0));
 
         // When
@@ -215,14 +212,12 @@ class AchievementServiceTest {
     @Test
     @DisplayName("Should award total elevation milestones")
     void testCheckAndAwardAchievements_TotalElevation() {
-        // Given - User has 5000m+ total elevation
+        // Given - Current activity crosses 5000m total elevation
+        Activity previous = createActivity(Activity.ActivityType.HIKE, 10000L, BigDecimal.valueOf(4500));
+        previous.setStartedAt(testTime.minusDays(1));
         Activity activity = createActivity(Activity.ActivityType.HIKE, 10000L, BigDecimal.valueOf(500));
 
-        when(activityRepository.countByUserId(userId)).thenReturn(20L);
+        stubHistory(previous, activity);
-        when(activityRepository.countByUserIdAndActivityType(any(), any())).thenReturn(10L);
-        when(activityRepository.sumDistanceByUserId(userId)).thenReturn(BigDecimal.valueOf(200000));
-        when(activityRepository.sumElevationGainByUserId(userId)).thenReturn(BigDecimal.valueOf(6000)); // 6000m total
-        when(activityRepository.countDistinctActivityTypesByUserId(userId)).thenReturn(2L);
         when(achievementRepository.save(any(Achievement.class))).thenAnswer(invocation -> invocation.getArgument(0));
 
         // When
@@ -240,13 +235,14 @@ class AchievementServiceTest {
     @Test
     @DisplayName("Should award variety seeker achievement")
     void testCheckAndAwardAchievements_VarietySeeker() {
-        // Given - User has tried 3+ different activity types
+        // Given - Current activity introduces the 3rd distinct activity type
+        Activity run = createActivity(Activity.ActivityType.RUN, 5000L, BigDecimal.ZERO);
+        run.setStartedAt(testTime.minusDays(2));
+        Activity ride = createActivity(Activity.ActivityType.RIDE, 20000L, BigDecimal.ZERO);
+        ride.setStartedAt(testTime.minusDays(1));
         Activity activity = createActivity(Activity.ActivityType.SWIM, 2000L, BigDecimal.ZERO);
 
-        when(activityRepository.countByUserId(userId)).thenReturn(15L);
+        stubHistory(run, ride, activity);
-        when(activityRepository.countByUserIdAndActivityType(any(), any())).thenReturn(5L);
-        when(activityRepository.sumDistanceByUserId(userId)).thenReturn(BigDecimal.valueOf(30000));
-        when(activityRepository.countDistinctActivityTypesByUserId(userId)).thenReturn(3L);
         when(achievementRepository.save(any(Achievement.class))).thenAnswer(invocation -> invocation.getArgument(0));
 
         // When
@@ -267,10 +263,7 @@ class AchievementServiceTest {
         metrics.setMaxSpeed(BigDecimal.valueOf(45.0)); // 45 km/h (realistic for cycling)
         activity.setMetrics(metrics);
 
-        when(activityRepository.countByUserId(userId)).thenReturn(10L);
+        stubHistory(activity);
-        when(activityRepository.countByUserIdAndActivityType(any(), any())).thenReturn(5L);
-        when(activityRepository.sumDistanceByUserId(userId)).thenReturn(BigDecimal.valueOf(200000));
-        when(activityRepository.countDistinctActivityTypesByUserId(userId)).thenReturn(1L);
         when(achievementRepository.save(any(Achievement.class))).thenAnswer(invocation -> invocation.getArgument(0));
 
         // When
@@ -285,19 +278,18 @@ class AchievementServiceTest {
     @Test
     @DisplayName("Should award 7-day streak achievement")
     void testCheckAndAwardAchievements_7DayStreak() {
-        // Given - User has 7+ consecutive days of activities
+        // Given - Current activity completes a 7-day streak
+        List<Activity> history = new ArrayList<>();
+        LocalDate anchorDate = testTime.toLocalDate();
+        for (int i = 6; i >= 1; i--) {
+            Activity previous = createActivity(Activity.ActivityType.RUN, 5000L, BigDecimal.ZERO);
+            previous.setStartedAt(anchorDate.minusDays(i).atTime(10, 0));
+            history.add(previous);
+        }
         Activity activity = createActivity(Activity.ActivityType.RUN, 5000L, BigDecimal.ZERO);
+        history.add(activity);
 
-        when(activityRepository.countByUserId(userId)).thenReturn(20L);
+        stubHistory(history);
-        when(activityRepository.countByUserIdAndActivityType(any(), any())).thenReturn(10L);
-        when(activityRepository.sumDistanceByUserId(userId)).thenReturn(BigDecimal.valueOf(100000));
-        when(activityRepository.countDistinctActivityTypesByUserId(userId)).thenReturn(1L);
-        // Streak source: 8 consecutive days of activity ending today, as raw timestamps
-        java.time.LocalDateTime now = java.time.LocalDateTime.now();
-        when(activityRepository.findActivityStartTimestampsSince(any(), any())).thenReturn(List.of(
-            now, now.minusDays(1), now.minusDays(2), now.minusDays(3),
-            now.minusDays(4), now.minusDays(5), now.minusDays(6), now.minusDays(7)
-        ));
         when(achievementRepository.save(any(Achievement.class))).thenAnswer(invocation -> invocation.getArgument(0));
 
         // When
@@ -314,8 +306,7 @@ class AchievementServiceTest {
     void testCheckAndAwardAchievements_AlreadyEarned() {
         // Given - User already has every achievement
         Activity activity = createActivity(Activity.ActivityType.RUN, 5000L, BigDecimal.ZERO);
-
+        stubHistory(activity);
-        when(activityRepository.countByUserId(userId)).thenReturn(10L);
         // Simulate "user already has all achievements" by returning one of every type from the
         // preload query that checkAndAwardAchievements uses to populate the in-memory set.
         List<Achievement> allEarned = new java.util.ArrayList<>();
@@ -359,11 +350,7 @@ class AchievementServiceTest {
         metrics.setMaxSpeed(BigDecimal.valueOf(16.0)); // 57.6 km/h (unrealistic for run, but for testing)
         activity.setMetrics(metrics);
 
-        when(activityRepository.countByUserId(userId)).thenReturn(1L); // First activity
+        stubHistory(activity);
-        when(activityRepository.countByUserIdAndActivityType(userId, Activity.ActivityType.RUN)).thenReturn(1L);
-        when(activityRepository.sumDistanceByUserId(userId)).thenReturn(BigDecimal.valueOf(5000));
-        when(activityRepository.sumElevationGainByUserId(userId)).thenReturn(BigDecimal.valueOf(1100));
-        when(activityRepository.countDistinctActivityTypesByUserId(userId)).thenReturn(1L);
         when(achievementRepository.save(any(Achievement.class))).thenAnswer(invocation -> invocation.getArgument(0));
 
         // When
@@ -380,6 +367,30 @@ class AchievementServiceTest {
         ));
     }
 
+    @Test
+    @DisplayName("Should use activity end time as earnedAt for historical milestone")
+    void testCheckAndAwardAchievements_UsesActivityEndTimeForEarnedAt() {
+        Activity previous = createActivity(Activity.ActivityType.RUN, 9000L, BigDecimal.ZERO);
+        previous.setStartedAt(LocalDateTime.of(2025, 11, 30, 10, 0));
+        previous.setEndedAt(LocalDateTime.of(2025, 11, 30, 11, 0));
+        Activity activity = createActivity(Activity.ActivityType.RUN, 2000L, BigDecimal.ZERO);
+        activity.setStartedAt(LocalDateTime.of(2025, 12, 1, 7, 15));
+        activity.setEndedAt(LocalDateTime.of(2025, 12, 1, 8, 5));
+
+        stubHistory(previous, activity);
+        when(achievementRepository.save(any(Achievement.class))).thenAnswer(invocation -> invocation.getArgument(0));
+
+        List<Achievement> achievements = achievementService.checkAndAwardAchievements(activity);
+
+        Achievement distanceAchievement = achievements.stream()
+                .filter(a -> a.getAchievementType() == Achievement.AchievementType.DISTANCE_10K)
+                .findFirst()
+                .orElseThrow();
+
+        assertEquals(activity.getEndedAt(), distanceAchievement.getEarnedAt());
+        assertEquals(activity.getId(), distanceAchievement.getActivityId());
+    }
+
     @Test
     @DisplayName("Should get user achievements")
     void testGetUserAchievements() {
@@ -421,6 +432,7 @@ class AchievementServiceTest {
                 .userId(userId)
                 .activityType(activityType)
                 .startedAt(testTime)
+                .endedAt(testTime.plusHours(1))
                 .totalDistance(BigDecimal.valueOf(distanceMeters))
                 .totalDurationSeconds(3600L)
                 .elevationGain(elevationGain)
@@ -439,4 +451,12 @@ class AchievementServiceTest {
                 .earnedAt(testTime)
                 .build();
     }
+
+    private void stubHistory(Activity... activities) {
+        stubHistory(List.of(activities));
+    }
+
+    private void stubHistory(List<Activity> activities) {
+        when(activityRepository.findByUserIdOrderByStartedAtAsc(userId)).thenReturn(activities);
+    }
 }