"""Быстрые тесты каркаса приложения: lifespan, /healthcheck, префикс API (без БД и NATS).

Аутентификация и supervisor NATS — tests/test_nats_core.py (подключение переехало в src/core/nats.py, рулинг R-3).
"""

import asyncio
import importlib
from http import HTTPStatus
from types import SimpleNamespace
from typing import Any

import httpx
import pytest

from src.api.router import router
from src.core.nats import NatsConnection

# src/__init__.py реэкспортирует объект app под именем модуля, поэтому модуль берём через importlib
app_module = importlib.import_module("src.app")


@pytest.fixture
async def client():
    # Без lifespan: app.state.nats не установлен — healthcheck обязан это пережить
    transport = httpx.ASGITransport(app=app_module.app)
    async with httpx.AsyncClient(transport=transport, base_url="http://test") as c:
        yield c


async def test_healthcheck_nats_off_when_disabled(client: httpx.AsyncClient, monkeypatch: pytest.MonkeyPatch):
    monkeypatch.setattr(app_module.settings, "NATS_ENABLED", False)

    response = await client.get("/healthcheck")

    assert response.status_code == HTTPStatus.OK
    body = response.json()
    assert body["nats"] == "off"
    assert {"uptime", "version"} <= set(body)


async def test_healthcheck_nats_down_when_enabled_without_connection(
    client: httpx.AsyncClient, monkeypatch: pytest.MonkeyPatch
):
    monkeypatch.setattr(app_module.settings, "NATS_ENABLED", True)

    response = await client.get("/healthcheck")

    assert response.status_code == HTTPStatus.OK
    assert response.json()["nats"] == "down"


@pytest.mark.parametrize(("connected", "expected"), [(True, "ok"), (False, "down")])
async def test_healthcheck_nats_follows_connection_state(
    client: httpx.AsyncClient, monkeypatch: pytest.MonkeyPatch, connected: bool, expected: str
):
    monkeypatch.setattr(app_module.settings, "NATS_ENABLED", True)
    monkeypatch.setattr(app_module.app.state, "nats", SimpleNamespace(is_connected=connected), raising=False)

    response = await client.get("/healthcheck")

    assert response.status_code == HTTPStatus.OK
    assert response.json()["nats"] == expected


def test_router_prefix():
    assert router.prefix == "/api/v1"


class _FakeNats:
    def __init__(self) -> None:
        self.started = False
        self.stopped = False
        self.is_connected = False

    async def start(self) -> None:
        self.started = True

    async def stop(self) -> None:
        self.stopped = True


class _FakeS3Client:
    def __init__(self) -> None:
        self.session_closed = False

    async def close_session(self) -> None:
        self.session_closed = True


@pytest.fixture
def _no_smb(monkeypatch: pytest.MonkeyPatch) -> None:
    monkeypatch.setattr(app_module.smbclient, "register_session", lambda *args, **kwargs: None)
    monkeypatch.setattr(app_module.smbclient, "reset_connection_cache", lambda: None)


@pytest.mark.usefixtures("_no_smb")
async def test_lifespan_starts_when_s3_and_nats_unavailable(monkeypatch: pytest.MonkeyPatch):
    async def unavailable() -> None:
        return None

    monkeypatch.setattr(app_module, "_connect_s3", unavailable)
    monkeypatch.setattr(app_module, "_create_nats", lambda: None)
    reached_yield = False

    async with app_module.lifespan(app_module.app):
        reached_yield = True
        assert app_module.app.state.storage is None
        assert app_module.app.state.nats is None

    assert reached_yield


@pytest.mark.usefixtures("_no_smb")
async def test_lifespan_starts_and_stops_nats_and_closes_s3(monkeypatch: pytest.MonkeyPatch):
    fake_nats = _FakeNats()
    s3_client = _FakeS3Client()
    storage = SimpleNamespace(client=s3_client)

    async def connect_s3() -> SimpleNamespace:
        return storage

    monkeypatch.setattr(app_module, "_connect_s3", connect_s3)
    monkeypatch.setattr(app_module, "_create_nats", lambda: fake_nats)

    async with app_module.lifespan(app_module.app):
        assert app_module.app.state.storage is storage
        assert app_module.app.state.nats is fake_nats
        assert fake_nats.started
        assert not fake_nats.stopped
        assert not s3_client.session_closed

    assert fake_nats.stopped
    assert s3_client.session_closed


class _NeverConnectingClient:
    """Клиент nats-py, который никогда не подключается: connect висит (как nats-py без сервера)."""

    is_connected = False
    is_closed = False

    async def connect(self, servers: str, **options: Any) -> None:
        await asyncio.Event().wait()

    async def close(self) -> None:
        self.is_closed = True


@pytest.mark.usefixtures("_no_smb")
async def test_lifespan_does_not_wait_for_nats_and_healthcheck_is_down(monkeypatch: pytest.MonkeyPatch):
    """Регрессия: недоступный NATS не задерживает старт; до первого подключения healthcheck показывает down."""

    async def unavailable() -> None:
        return None

    nats = NatsConnection(app_module.settings.OPENBAO.NATS, client_factory=_NeverConnectingClient)
    monkeypatch.setattr(app_module, "_connect_s3", unavailable)
    monkeypatch.setattr(app_module, "_create_nats", lambda: nats)
    monkeypatch.setattr(app_module.settings, "NATS_ENABLED", True)

    async with app_module.lifespan(app_module.app):
        transport = httpx.ASGITransport(app=app_module.app)
        async with httpx.AsyncClient(transport=transport, base_url="http://test") as c:
            response = await c.get("/healthcheck")
        assert response.json()["nats"] == "down"

    assert not nats.is_connected


def test_create_nats_disabled_returns_none(monkeypatch: pytest.MonkeyPatch):
    monkeypatch.setattr(app_module.settings, "NATS_ENABLED", False)
    assert app_module._create_nats() is None


def test_create_nats_enabled_returns_connection_for_results(monkeypatch: pytest.MonkeyPatch):
    monkeypatch.setattr(app_module.settings, "NATS_ENABLED", True)
    nats = app_module._create_nats()
    assert isinstance(nats, NatsConnection)
    assert (nats.result_subject, nats.queue) == ("recognition.result", "arm-core")
    assert not nats.is_connected  # создание не подключает: подключение — в start()