"""
Tests for tui/events.py — subscribe/unsubscribe broadcast, signal_channel_changed.
"""

import queue
import pytest
from tui import events as bus


@pytest.fixture(autouse=True)
def reset_bus():
    """Reset all bus state between tests."""
    bus._queue = None
    bus.tui_active = False
    bus._subscribers.clear()
    bus._bot_loop = None
    bus._bot_ch_ev = None
    yield
    bus._queue = None
    bus.tui_active = False
    bus._subscribers.clear()
    bus._bot_loop = None
    bus._bot_ch_ev = None


class TestInitBus:
    def test_init_creates_queue(self):
        q = bus.init_bus()
        assert q is not None
        assert bus.tui_active is True

    def test_get_bus_returns_same_queue(self):
        q = bus.init_bus()
        assert bus.get_bus() is q


class TestPost:
    def test_post_before_init_is_silent(self):
        bus.post("event")  # should not raise

    def test_post_reaches_tui_queue(self):
        q = bus.init_bus()
        bus.post("hello")
        assert q.get_nowait() == "hello"

    def test_post_reaches_subscriber(self):
        bus.init_bus()
        sub = bus.subscribe()
        bus.post("world")
        assert sub.get_nowait() == "world"

    def test_post_reaches_multiple_subscribers(self):
        bus.init_bus()
        s1 = bus.subscribe()
        s2 = bus.subscribe()
        bus.post(42)
        assert s1.get_nowait() == 42
        assert s2.get_nowait() == 42


class TestSubscribeUnsubscribe:
    def test_subscribe_returns_queue(self):
        q = bus.subscribe()
        assert isinstance(q, queue.Queue)
        assert q in bus._subscribers

    def test_unsubscribe_removes_queue(self):
        q = bus.subscribe()
        bus.unsubscribe(q)
        assert q not in bus._subscribers

    def test_unsubscribe_twice_is_safe(self):
        q = bus.subscribe()
        bus.unsubscribe(q)
        bus.unsubscribe(q)  # should not raise

    def test_unsubscribed_does_not_receive(self):
        bus.init_bus()
        sub = bus.subscribe()
        bus.unsubscribe(sub)
        bus.post("gone")
        with pytest.raises(queue.Empty):
            sub.get_nowait()


class TestSignalChannelChanged:
    def test_signal_without_context_is_safe(self):
        bus.signal_channel_changed()  # should not raise

    def test_set_bot_context_stores_refs(self):
        import asyncio

        async def _inner():
            loop = asyncio.get_event_loop()
            ev = asyncio.Event()
            bus.set_bot_context(loop, ev)
            assert bus._bot_loop is loop
            assert bus._bot_ch_ev is ev

        asyncio.run(_inner())

    def test_signal_sets_event(self):
        import asyncio

        async def _inner():
            loop = asyncio.get_event_loop()
            ev = asyncio.Event()
            bus.set_bot_context(loop, ev)
            assert not ev.is_set()
            bus.signal_channel_changed()
            # give the call_soon_threadsafe a chance to fire
            await asyncio.sleep(0)
            assert ev.is_set()

        asyncio.run(_inner())