import pytest

from notifier import Notifier
from player_mock import Player

@pytest.fixture
def mockPlayer():
    return Player()

@pytest.fixture
def uut(mockPlayer):
    return Notifier(mockPlayer)

def checkEvent(uut, event):
    callbacks = 2
    calledFlags = [False] * 2

    def createCallback(i):
        def cb():
            nonlocal calledFlags
            calledFlags[i] = True
        return cb

    for i in range(0, callbacks):
        uut.registerCallback(event, createCallback(i))

    assert not any(calledFlags)
    uut.notify(event)
    assert all(calledFlags)

def test_allEvents(uut):
    checkEvent(uut, Notifier.PLAYING_STATE_EVENT)
    checkEvent(uut, Notifier.PLAYBACK_VOLUME_EVENT)
    checkEvent(uut, Notifier.PLAYBACK_RATE_EVENT)

def test_eventWithoutRegisteredCallbacks(uut):
    uut.notify(Notifier.PLAYING_STATE_EVENT)
    # expect no crash

def test_eventsWithMockPlayer(uut, mockPlayer):
    def testEvent(eventCode, simulateEvent):
        called = False
        def callback():
            nonlocal called
            called = True

        uut.registerCallback(eventCode, callback)

        assert not called
        simulateEvent()
        assert called

    testEvent(Notifier.PLAYING_STATE_EVENT, mockPlayer.simulatePlayingStateChanged)
    testEvent(Notifier.PLAYBACK_VOLUME_EVENT, mockPlayer.simulatePlaybackVolumeChanged)

def test_singleEventNotification(uut):
    playingStateCalled = False
    def playingStateCallback():
        nonlocal playingStateCalled
        playingStateCalled = True

    volumeCalled = False
    def volumeCallback():
        nonlocal volumeCalled
        volumeCalled = True

    uut.registerCallback(Notifier.PLAYING_STATE_EVENT, playingStateCallback)
    uut.registerCallback(Notifier.PLAYBACK_VOLUME_EVENT, volumeCallback)

    assert not playingStateCalled
    assert not volumeCalled

    uut.notify(Notifier.PLAYING_STATE_EVENT)
    assert playingStateCalled
    assert not volumeCalled

    playingStateCalled = False

    uut.notify(Notifier.PLAYBACK_VOLUME_EVENT)
    assert not playingStateCalled
    assert volumeCalled

    volumeCalled = False

    uut.notify(Notifier.PLAYBACK_RATE_EVENT)
    assert not playingStateCalled
    assert not volumeCalled