import persontracking.lidar_tracker_pb2 as lidar_tracker_pb2
from persontracking.lidar_tracker_pb2_grpc import PersonTrackingServicer
from persontracking.lidar_cache import LidarCache
from multiprocessing import Process


class LidarServicer(PersonTrackingServicer):
    lidar_thread = None

    def __init__(self):
        self.cache = LidarCache(measurements=100)

    def set_tracking_group(self, request, context):
        pass

    def stop_tracking(self, request, context):
        self.cache.stop_scanning()
        self.lidar_thread.join()
        self.lidar_thread = None

    def start_tracking(self, request, context):
        '''
        Starts the lidar cache. 
        '''
        if self.lidar_thread is None:
            self.lidar_thread = Process(target=self.cache.do_scanning)