# Copyright (c) 2017 The University of Manchester
#
# 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
#
#     https://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.
from __future__ import annotations
# pylint: disable=no-name-in-module
from typing import ContextManager, Iterable, TYPE_CHECKING
from typing_extensions import Literal
if TYPE_CHECKING:
    from .data_speed_up_packet_gatherer_machine_vertex import (
        DataSpeedUpPacketGatherMachineVertex)


class StreamingContextManager(ContextManager[None]):
    """
    The implementation of the context manager object for streaming
    configuration control.
    """
    __slots__ = ("_gatherers", )

    def __init__(
            self, gatherers: Iterable[DataSpeedUpPacketGatherMachineVertex]):
        """
        :param iterable(DataSpeedUpPacketGatherMachineVertex) gatherers:
        """
        self._gatherers = list(gatherers)

    def __enter__(self) -> None:
        for gatherer in self._gatherers:
            gatherer.load_system_routing_tables()
        for gatherer in self._gatherers:
            gatherer.set_cores_for_data_streaming()

    def __exit__(self, _type, _value, _tb) -> Literal[False]:
        for gatherer in self._gatherers:
            gatherer.unset_cores_for_data_streaming()
        for gatherer in self._gatherers:
            gatherer.load_application_routing_tables()
        return False
