text: # Copyright (c) Microsoft Corporation.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  # http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  
  import asyncio
  from pathlib import Path
  from typing import Any, Dict, List, Set, Union
  
  from playwright._impl._api_types import Error
  from playwright._impl._connection import ChannelOwner
  from playwright._impl._helper import async_readfile
  
  
  class Selectors:
      def __init__(self, loop: asyncio.AbstractEventLoop) -> None:
          self._loop = loop
          self._channels: Set[SelectorsOwner] = set()
          self._registrations: List[Dict] = []
  
      async def register(
          self,
          name: str,
          script: str = None,
          path: Union[str, Path] = None,
          contentScript: bool = None,
      ) -> None:
          if not script and not path:
              raise Error("Either source or path should be specified")
          if path:
              script = (await async_readfile(path)).decode()
          params: Dict[str, Any] = dict(name=name, source=script)
          if contentScript:
              params["contentScript"] = True
          for channel in self._channels:
              await channel._channel.send("register", params)
          self._registrations.append(params)
  
      def _add_channel(self, channel: "SelectorsOwner") -> None:
          self._channels.add(channel)
          for params in self._registrations:
              # This should not fail except for connection closure, but just in case we catch.
              channel._channel.send_no_reply("register", params)
  
      def _remove_channel(self, channel: "SelectorsOwner") -> None:
          if channel in self._channels:
              self._channels.remove(channel)
  
  
  class SelectorsOwner(ChannelOwner):
      def __init__(
          self, parent: ChannelOwner, type: str, guid: str, initializer: Dict
      ) -> None:
          super().__init__(parent, type, guid, initializer)
  