import multiprocessing
import random
import signal
import pickle
import pytest

from sanic.testing import HOST, PORT
from sanic.response import text


@pytest.mark.skipif(
    not hasattr(signal, 'SIGALRM'),
    reason='SIGALRM is not implemented for this platform, we have to come '
    'up with another timeout strategy to test these'
)
def test_multiprocessing(app):
    """Tests that the number of children we produce is correct"""
    # Selects a number at random so we can spot check
    num_workers = random.choice(range(2, multiprocessing.cpu_count() * 2 + 1))
    process_list = set()

    def stop_on_alarm(*args):
        for process in multiprocessing.active_children():
            process_list.add(process.pid)
            process.terminate()

    signal.signal(signal.SIGALRM, stop_on_alarm)
    signal.alarm(3)
    app.run(HOST, PORT, workers=num_workers)

    assert len(process_list) == num_workers


def test_multiprocessing_with_blueprint(app):
    from sanic import Blueprint
    # Selects a number at random so we can spot check
    num_workers = random.choice(range(2, multiprocessing.cpu_count() * 2 + 1))
    process_list = set()

    def stop_on_alarm(*args):
        for process in multiprocessing.active_children():
            process_list.add(process.pid)
            process.terminate()

    signal.signal(signal.SIGALRM, stop_on_alarm)
    signal.alarm(3)

    bp = Blueprint('test_text')
    app.blueprint(bp)
    app.run(HOST, PORT, workers=num_workers)

    assert len(process_list) == num_workers


# this function must be outside a test function so that it can be
# able to be pickled (local functions cannot be pickled).
def handler(request):
    return text('Hello')

# Muliprocessing on Windows requires app to be able to be pickled
@pytest.mark.parametrize('protocol', [3, 4])
def test_pickle_app(app, protocol):
    app.route('/')(handler)
    p_app = pickle.dumps(app, protocol=protocol)
    up_p_app = pickle.loads(p_app)
    assert up_p_app
    request, response = app.test_client.get('/')
    assert response.text == 'Hello'


@pytest.mark.parametrize('protocol', [3, 4])
def test_pickle_app_with_bp(app, protocol):
    from sanic import Blueprint
    bp = Blueprint('test_text')
    bp.route('/')(handler)
    app.blueprint(bp)
    p_app = pickle.dumps(app, protocol=protocol)
    up_p_app = pickle.loads(p_app)
    assert up_p_app
    request, response = app.test_client.get('/')
    assert app.is_request_stream is False
    assert response.text == 'Hello'