import threading

class SessionManager:
    def __init__(self, sess):
        self.sess = sess
        self._lock = threading.Lock()
        self._running_count = 0  # wie viele Devices wollen gerade streamen?

    def start(self):
        with self._lock:
            if self._running_count == 0:
                # Erster „Kunde“ → Session-Stream starten
                self.sess.start(0)  # 0 = endlos
            self._running_count += 1
            return self._running_count

    def stop(self):
        with self._lock:
            if self._running_count > 0:
                self._running_count -= 1
                if self._running_count == 0:
                    # Letzter „Kunde“ ist weg → Session beenden
                    self.sess.end()
            return self._running_count

    def running_devices(self):
        with self._lock:
            return self._running_count