Improve Stopwatch behavior (#18930)

- Don't send empty stopwatch over and over again, only send once.
- Stop interval to update stopwatch's timer when there is no more stopwatch.

models/issue_stopwatch.go

@@ -66,6 +66,38 @@ func getStopwatch(ctx context.Context, userID, issueID int64) (sw *Stopwatch, ex
 	return
 }
 
+// UserIDCount is a simple coalition of UserID and Count
+type UserStopwatch struct {
+	UserID      int64
+	StopWatches []*Stopwatch
+}
+
+// GetUIDsAndNotificationCounts between the two provided times
+func GetUIDsAndStopwatch() ([]*UserStopwatch, error) {
+	sws := []*Stopwatch{}
+	if err := db.GetEngine(db.DefaultContext).Find(&sws); err != nil {
+		return nil, err
+	}
+	if len(sws) == 0 {
+		return []*UserStopwatch{}, nil
+	}
+
+	lastUserID := int64(-1)
+	res := []*UserStopwatch{}
+	for _, sw := range sws {
+		if lastUserID == sw.UserID {
+			lastUserStopwatch := res[len(res)-1]
+			lastUserStopwatch.StopWatches = append(lastUserStopwatch.StopWatches, sw)
+		} else {
+			res = append(res, &UserStopwatch{
+				UserID:      sw.UserID,
+				StopWatches: []*Stopwatch{sw},
+			})
+		}
+	}
+	return res, nil
+}
+
 // GetUserStopwatches return list of all stopwatches of a user
 func GetUserStopwatches(userID int64, listOptions db.ListOptions) ([]*Stopwatch, error) {
 	sws := make([]*Stopwatch, 0, 8)