"""
Test for io_services_test_stubs.py

"""

try:
    import asyncio
except ImportError:
    asyncio = None

import sys
import threading
import unittest

import tornado.ioloop
import twisted.internet.reactor

from pika.adapters import select_connection

from tests.stubs.io_services_test_stubs import IOServicesTestStubs


# Suppress invalid-name, since our test names are descriptive and quite long
# pylint: disable=C0103

# Suppress missing-docstring to allow test method names to be printed by our the
# test runner
# pylint: disable=C0111


# Tornado does some magic that substitutes the class dynamically
_TORNADO_IO_LOOP = tornado.ioloop.IOLoop()
_TORNADO_IOLOOP_CLASS = _TORNADO_IO_LOOP.__class__
_TORNADO_IO_LOOP.close()
del _TORNADO_IO_LOOP

_SUPPORTED_LOOP_CLASSES = {
    select_connection.IOLoop,
    _TORNADO_IOLOOP_CLASS,
}

if asyncio is not None:
    if sys.platform == 'win32':
        asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())
    _SUPPORTED_LOOP_CLASSES.add(asyncio.get_event_loop().__class__)


class TestStartCalledFromOtherThreadAndWithVaryingNativeLoops(
        unittest.TestCase,
        IOServicesTestStubs):

    _native_loop_classes = None

    @classmethod
    def setUpClass(cls):
        cls._native_loop_classes = set()

    # AssertionError: Expected these 3 native I/O loop classes from IOServicesTestStubs:
    # {<class 'asyncio.windows_events.ProactorEventLoop'>, <class 'tornado.platform.asyncio.AsyncIOLoop'>, <class 'pika.adapters.select_connection.IOLoop'>}
    # but got these 3:
    # {<class 'asyncio.windows_events._WindowsSelectorEventLoop'>, <class 'tornado.platform.asyncio.AsyncIOLoop'>, <class 'pika.adapters.select_connection.IOLoop'>} 
    @classmethod
    def tearDownClass(cls):
        # Now check against what was made available to us by
        # IOServicesTestStubs
        if cls._native_loop_classes != _SUPPORTED_LOOP_CLASSES:
            raise AssertionError(
                'Expected these {} native I/O loop classes from '
                'IOServicesTestStubs: {!r}, but got these {}: {!r}'.format(
                    len(_SUPPORTED_LOOP_CLASSES),
                    _SUPPORTED_LOOP_CLASSES,
                    len(cls._native_loop_classes),
                    cls._native_loop_classes))

    def setUp(self):
        self._runner_thread_id = threading.current_thread().ident

    def start(self):
        nbio = self.create_nbio()
        native_loop = nbio.get_native_ioloop()
        self.assertIsNotNone(self._native_loop)
        self.assertIs(native_loop, self._native_loop)

        self._native_loop_classes.add(native_loop.__class__)

        # Check that we're called from a different thread than the one that
        # set up this test.
        self.assertNotEqual(threading.current_thread().ident,
                            self._runner_thread_id)

        # And make sure the loop actually works using this rudimentary test
        nbio.add_callback_threadsafe(nbio.stop)
        nbio.run()