"""Test asyncio support"""
# Copyright (c) PyZMQ Developers
# Distributed under the terms of the Modified BSD License.

import json
from multiprocessing import Process
import os
import sys

import pytest
from pytest import mark

import zmq
from zmq.utils.strtypes import u

try:
    import asyncio
    import zmq.asyncio as zaio
    from zmq.auth.asyncio import AsyncioAuthenticator
except ImportError:
    if sys.version_info >= (3,4):
        raise
    asyncio = None

from concurrent.futures import CancelledError
from zmq.tests import BaseZMQTestCase, SkipTest
from zmq.tests.test_auth import TestThreadAuthentication


class ProcessForTeardownTest(Process):
    def __init__(self, event_loop_policy_class):
        Process.__init__(self)
        self.event_loop_policy_class = event_loop_policy_class

    def run(self):
        """Leave context, socket and event loop upon implicit disposal"""
        asyncio.set_event_loop_policy(self.event_loop_policy_class())

        actx = zaio.Context.instance()
        socket = actx.socket(zmq.PAIR)
        socket.bind_to_random_port('tcp://127.0.0.1')

        @asyncio.coroutine
        def never_ending_task(socket):
            yield from socket.recv()  # never ever receive anything

        loop = asyncio.get_event_loop()
        coro = asyncio.wait_for(never_ending_task(socket), timeout=1)
        try:
            loop.run_until_complete(coro)
        except asyncio.TimeoutError:
            pass  # expected timeout
        else:
            assert False, "never_ending_task was completed unexpectedly"


class TestAsyncIOSocket(BaseZMQTestCase):
    if asyncio is not None:
        Context = zaio.Context

    def setUp(self):
        if asyncio is None:
            raise SkipTest()
        self.loop = asyncio.new_event_loop()
        asyncio.set_event_loop(self.loop)
        super(TestAsyncIOSocket, self).setUp()

    def tearDown(self):
        self.loop.close()
        super().tearDown()

    def test_socket_class(self):
        s = self.context.socket(zmq.PUSH)
        assert isinstance(s, zaio.Socket)
        s.close()

    def test_instance_subclass_first(self):
        actx = zmq.asyncio.Context.instance()
        ctx = zmq.Context.instance()
        ctx.term()
        actx.term()
        assert type(ctx) is zmq.Context
        assert type(actx) is zmq.asyncio.Context

    def test_instance_subclass_second(self):
        ctx = zmq.Context.instance()
        actx = zmq.asyncio.Context.instance()
        ctx.term()
        actx.term()
        assert type(ctx) is zmq.Context
        assert type(actx) is zmq.asyncio.Context

    def test_recv_multipart(self):
        @asyncio.coroutine
        def test():
            a, b = self.create_bound_pair(zmq.PUSH, zmq.PULL)
            f = b.recv_multipart()
            assert not f.done()
            yield from a.send(b'hi')
            recvd = yield from f
            self.assertEqual(recvd, [b'hi'])
        self.loop.run_until_complete(test())

    def test_recv(self):
        @asyncio.coroutine
        def test():
            a, b = self.create_bound_pair(zmq.PUSH, zmq.PULL)
            f1 = b.recv()
            f2 = b.recv()
            assert not f1.done()
            assert not f2.done()
            yield from  a.send_multipart([b'hi', b'there'])
            recvd = yield from f2
            assert f1.done()
            self.assertEqual(f1.result(), b'hi')
            self.assertEqual(recvd, b'there')
        self.loop.run_until_complete(test())

    @mark.skipif(not hasattr(zmq, 'RCVTIMEO'), reason="requires RCVTIMEO")
    def test_recv_timeout(self):
        @asyncio.coroutine
        def test():
            a, b = self.create_bound_pair(zmq.PUSH, zmq.PULL)
            b.rcvtimeo = 100
            f1 = b.recv()
            b.rcvtimeo = 1000
            f2 = b.recv_multipart()
            with self.assertRaises(zmq.Again):
                yield from f1
            yield from a.send_multipart([b'hi', b'there'])
            recvd = yield from f2
            assert f2.done()
            self.assertEqual(recvd, [b'hi', b'there'])
        self.loop.run_until_complete(test())

    @mark.skipif(not hasattr(zmq, 'SNDTIMEO'), reason="requires SNDTIMEO")
    def test_send_timeout(self):
        @asyncio.coroutine
        def test():
            s = self.socket(zmq.PUSH)
            s.sndtimeo = 100
            with self.assertRaises(zmq.Again):
                yield from s.send(b'not going anywhere')
        self.loop.run_until_complete(test())

    def test_recv_string(self):
        @asyncio.coroutine
        def test():
            a, b = self.create_bound_pair(zmq.PUSH, zmq.PULL)
            f = b.recv_string()
            assert not f.done()
            msg = u('πøøπ')
            yield from a.send_string(msg)
            recvd = yield from f
            assert f.done()
            self.assertEqual(f.result(), msg)
            self.assertEqual(recvd, msg)
        self.loop.run_until_complete(test())

    def test_recv_json(self):
        @asyncio.coroutine
        def test():
            a, b = self.create_bound_pair(zmq.PUSH, zmq.PULL)
            f = b.recv_json()
            assert not f.done()
            obj = dict(a=5)
            yield from a.send_json(obj)
            recvd = yield from f
            assert f.done()
            self.assertEqual(f.result(), obj)
            self.assertEqual(recvd, obj)
        self.loop.run_until_complete(test())

    def test_recv_json_cancelled(self):
        @asyncio.coroutine
        def test():
            a, b = self.create_bound_pair(zmq.PUSH, zmq.PULL)
            f = b.recv_json()
            assert not f.done()
            f.cancel()
            # cycle eventloop to allow cancel events to fire
            yield from asyncio.sleep(0)
            obj = dict(a=5)
            yield from a.send_json(obj)
            # CancelledError change in 3.8 https://bugs.python.org/issue32528
            if sys.version_info < (3, 8):
                with pytest.raises(CancelledError):
                    recvd = yield from f
            else:
                with pytest.raises(asyncio.exceptions.CancelledError):
                    recvd = yield from f
            assert f.done()
            # give it a chance to incorrectly consume the event
            events = yield from b.poll(timeout=5)
            assert events
            yield from asyncio.sleep(0)
            # make sure cancelled recv didn't eat up event
            f = b.recv_json()
            recvd = yield from asyncio.wait_for(f, timeout=5)
            assert recvd == obj
        self.loop.run_until_complete(test())

    def test_recv_pyobj(self):
        @asyncio.coroutine
        def test():
            a, b = self.create_bound_pair(zmq.PUSH, zmq.PULL)
            f = b.recv_pyobj()
            assert not f.done()
            obj = dict(a=5)
            yield from a.send_pyobj(obj)
            recvd = yield from f
            assert f.done()
            self.assertEqual(f.result(), obj)
            self.assertEqual(recvd, obj)
        self.loop.run_until_complete(test())


    def test_custom_serialize(self):
        def serialize(msg):
            frames = []
            frames.extend(msg.get('identities', []))
            content = json.dumps(msg['content']).encode('utf8')
            frames.append(content)
            return frames

        def deserialize(frames):
            identities = frames[:-1]
            content = json.loads(frames[-1].decode('utf8'))
            return {
                'identities': identities,
                'content': content,
            }

        @asyncio.coroutine
        def test():
            a, b = self.create_bound_pair(zmq.DEALER, zmq.ROUTER)

            msg = {
                'content': {
                    'a': 5,
                    'b': 'bee',
                }
            }
            yield from a.send_serialized(msg, serialize)
            recvd = yield from b.recv_serialized(deserialize)
            assert recvd['content'] == msg['content']
            assert recvd['identities']
            # bounce back, tests identities
            yield from b.send_serialized(recvd, serialize)
            r2 = yield from a.recv_serialized(deserialize)
            assert r2['content'] == msg['content']
            assert not r2['identities']
        self.loop.run_until_complete(test())

    def test_custom_serialize_error(self):
        @asyncio.coroutine
        def test():
            a, b = self.create_bound_pair(zmq.DEALER, zmq.ROUTER)

            msg = {
                'content': {
                    'a': 5,
                    'b': 'bee',
                }
            }
            with pytest.raises(TypeError):
                yield from a.send_serialized(json, json.dumps)

            yield from a.send(b'not json')
            with pytest.raises(TypeError):
                recvd = yield from b.recv_serialized(json.loads)
        self.loop.run_until_complete(test())

    def test_recv_dontwait(self):
        @asyncio.coroutine
        def test():
            push, pull = self.create_bound_pair(zmq.PUSH, zmq.PULL)
            f = pull.recv(zmq.DONTWAIT)
            with self.assertRaises(zmq.Again):
                yield from f
            yield from push.send(b'ping')
            yield from pull.poll() # ensure message will be waiting
            f = pull.recv(zmq.DONTWAIT)
            assert f.done()
            msg = yield from f
            self.assertEqual(msg, b'ping')
        self.loop.run_until_complete(test())

    def test_recv_cancel(self):
        @asyncio.coroutine
        def test():
            a, b = self.create_bound_pair(zmq.PUSH, zmq.PULL)
            f1 = b.recv()
            f2 = b.recv_multipart()
            assert f1.cancel()
            assert f1.done()
            assert not f2.done()
            yield from a.send_multipart([b'hi', b'there'])
            recvd = yield from f2
            assert f1.cancelled()
            assert f2.done()
            self.assertEqual(recvd, [b'hi', b'there'])
        self.loop.run_until_complete(test())

    def test_poll(self):
        @asyncio.coroutine
        def test():
            a, b = self.create_bound_pair(zmq.PUSH, zmq.PULL)
            f = b.poll(timeout=0)
            yield from asyncio.sleep(0)
            self.assertEqual(f.result(), 0)

            f = b.poll(timeout=1)
            assert not f.done()
            evt = yield from f

            self.assertEqual(evt, 0)

            f = b.poll(timeout=1000)
            assert not f.done()
            yield from a.send_multipart([b'hi', b'there'])
            evt = yield from f
            self.assertEqual(evt, zmq.POLLIN)
            recvd = yield from b.recv_multipart()
            self.assertEqual(recvd, [b'hi', b'there'])
        self.loop.run_until_complete(test())

    def test_poll_base_socket(self):
        @asyncio.coroutine
        def test():
            ctx = zmq.Context()
            url = 'inproc://test'
            a = ctx.socket(zmq.PUSH)
            b = ctx.socket(zmq.PULL)
            self.sockets.extend([a, b])
            a.bind(url)
            b.connect(url)

            poller = zaio.Poller()
            poller.register(b, zmq.POLLIN)

            f = poller.poll(timeout=1000)
            assert not f.done()
            a.send_multipart([b'hi', b'there'])
            evt = yield from f
            self.assertEqual(evt, [(b, zmq.POLLIN)])
            recvd = b.recv_multipart()
            self.assertEqual(recvd, [b'hi', b'there'])
        self.loop.run_until_complete(test())

    def test_poll_on_closed_socket(self):
        @asyncio.coroutine
        def test():
            a, b = self.create_bound_pair(zmq.PUSH, zmq.PULL)

            f = b.poll(timeout=1)
            b.close()

            # The test might stall if we try to yield from f directly so instead just make a few
            # passes through the event loop to schedule and execute all callbacks
            for _ in range(5):
                yield from asyncio.sleep(0)
                if f.cancelled():
                    break
            assert f.cancelled()

        self.loop.run_until_complete(test())

    @pytest.mark.skipif(
        sys.platform.startswith('win'),
        reason='Windows does not support polling on files')
    def test_poll_raw(self):
        @asyncio.coroutine
        def test():
            p = zaio.Poller()
            # make a pipe
            r, w = os.pipe()
            r = os.fdopen(r, 'rb')
            w = os.fdopen(w, 'wb')

            # POLLOUT
            p.register(r, zmq.POLLIN)
            p.register(w, zmq.POLLOUT)
            evts = yield from p.poll(timeout=1)
            evts = dict(evts)
            assert r.fileno() not in evts
            assert w.fileno() in evts
            assert evts[w.fileno()] == zmq.POLLOUT

            # POLLIN
            p.unregister(w)
            w.write(b'x')
            w.flush()
            evts = yield from p.poll(timeout=1000)
            evts = dict(evts)
            assert r.fileno() in evts
            assert evts[r.fileno()] == zmq.POLLIN
            assert r.read(1) == b'x'
            r.close()
            w.close()

        loop = asyncio.get_event_loop()
        loop.run_until_complete(test())

    def test_shadow(self):
        @asyncio.coroutine
        def test():
            ctx = zmq.Context()
            s = ctx.socket(zmq.PULL)
            async_s = zaio.Socket(s)
            assert isinstance(async_s, self.socket_class)

    def test_process_teardown(self):
        event_loop_policy_class = type(asyncio.get_event_loop_policy())
        proc = ProcessForTeardownTest(event_loop_policy_class)
        proc.start()
        try:
            proc.join(10)  # starting new Python process may cost a lot
            self.assertEqual(proc.exitcode, 0,
                             "Python process died with code %d" % proc.exitcode
                             if proc.exitcode else "process teardown hangs")
        finally:
            proc.terminate()


class TestAsyncioAuthentication(TestThreadAuthentication):
    """Test authentication running in a asyncio task"""

    if asyncio is not None:
        Context = zaio.Context

    def shortDescription(self):
        """Rewrite doc strings from TestThreadAuthentication from
        'threaded' to 'asyncio'.
        """
        doc = self._testMethodDoc
        if doc:
            doc = doc.split("\n")[0].strip()
            if doc.startswith('threaded auth'):
                doc = doc.replace('threaded auth', 'asyncio auth')
        return doc

    def setUp(self):
        if asyncio is None:
            raise SkipTest()
        self.loop = zaio.ZMQEventLoop()
        asyncio.set_event_loop(self.loop)
        super().setUp()

    def tearDown(self):
        super().tearDown()
        self.loop.close()

    def make_auth(self):
        return AsyncioAuthenticator(self.context)

    def can_connect(self, server, client):
        """Check if client can connect to server using tcp transport"""
        @asyncio.coroutine
        def go():
            result = False
            iface = 'tcp://127.0.0.1'
            port = server.bind_to_random_port(iface)
            client.connect("%s:%i" % (iface, port))
            msg = [b"Hello World"]
            yield from server.send_multipart(msg)
            if (yield from client.poll(1000)):
                rcvd_msg = yield from client.recv_multipart()
                self.assertEqual(rcvd_msg, msg)
                result = True
            return result
        return self.loop.run_until_complete(go())

    def _select_recv(self, multipart, socket, **kwargs):
        recv = socket.recv_multipart if multipart else socket.recv
        @asyncio.coroutine
        def coro():
            if not (yield from socket.poll(5000)):
                raise TimeoutError("Should have received a message")
            return (yield from recv(**kwargs))
        return self.loop.run_until_complete(coro())