app/backend/tests/flow/test_device_node.py

"""A device node: never run by the engine, degraded while its device is away."""

import asyncio
from pathlib import Path

import pytest

from fluksio.flow.alerts import Alert, AlertManager, AlertsConfig, Channel, Rule
from fluksio.flow.controller import HEALTH_FLOOR, FlowController
from fluksio.flow.devices import presence
from fluksio.flow.events import EventBus
from fluksio.flow.messages import DType, MessageSpec
from fluksio.flow.schemas import FlowDef, FlowInput, NodeDef
from fluksio.flow.store import FlowStore


def _controller(tmp_path: Path) -> FlowController:
    store = FlowStore(tmp_path / "flows")
    store.write_flow(
        FlowDef(
            name="hall",
            inputs=[
                FlowInput(spec=MessageSpec(name="level", dtype=DType.INT), initial=50)
            ],
            nodes=[
                NodeDef(
                    id="panel",
                    type="device",
                    params={"device": "wall"},
                    provides=[
                        MessageSpec(name="bell", port="gpio.4", dtype=DType.BOOL)
                    ],
                    requires=[
                        MessageSpec(
                            name="level",
                            port="backlight",
                            dtype=DType.INT,
                            trigger=False,
                        )
                    ],
                ),
                NodeDef(
                    id="ring",
                    type="change",
                    requires=[MessageSpec(name="bell", dtype=DType.BOOL)],
                    provides=[MessageSpec(name="rung", dtype=DType.BOOL)],
                ),
            ],
        )
    )
    return FlowController(store)


def test_the_engine_never_runs_a_device_node(tmp_path: Path) -> None:
    controller = _controller(tmp_path)
    asyncio.run(controller.reload())
    assert controller.issues == []
    node = controller.get_node("hall.panel")
    assert node is not None and node.passive
    ran: list[object] = []
    node.f = lambda **kwargs: ran.append(kwargs)  # type: ignore[method-assign]

    # The message its out port follows changes, and a manual run of the flow.
    controller.publish_message("hall.level", 80)
    controller.run_flow("hall")
    assert ran == []

    # What the device publishes on its in port runs what reads it.
    controller.publish_message("hall.bell", True)
    assert controller.values("hall")["hall.rung"]["value"] is True
    asyncio.run(controller._teardown())


def test_a_device_node_is_degraded_while_its_device_is_away(tmp_path: Path) -> None:
    controller = _controller(tmp_path)

    async def scenario() -> list[tuple[str, str | None]]:
        await controller.reload()
        entry = controller.loaded["hall.panel"]
        seen = [(entry.health, entry.health_detail)]
        presence.opened("wall")
        seen.append((entry.health, entry.health_detail))
        presence.closed("wall")
        seen.append((entry.health, entry.health_detail))
        await controller._teardown()
        # Stopped, it no longer follows the device.
        presence.opened("wall")
        seen.append((entry.health, entry.health_detail))
        presence.closed("wall")
        return seen

    # Degraded, not down: a switched-off panel is a warning, never a fault.
    assert asyncio.run(scenario()) == [
        ("degraded", "Offline"),
        ("ok", None),
        ("degraded", "Offline"),
        ("degraded", "Offline"),
    ]
    presence.forget("wall")


def test_an_offline_device_is_a_warning_not_a_fault(tmp_path: Path) -> None:
    controller = _controller(tmp_path)

    async def scenario() -> list:
        await controller.reload()
        # Past the floor that holds back a device rebooting.
        controller.loaded["hall.panel"].health_since -= 3600
        found = (
            controller.unhealthy_nodes(),
            [e.id for e in controller.unhealthy_nodes(health="degraded")],
            [(i.code, i.advisory) for i in controller.flow_issues("hall")],
        )
        await controller._teardown()
        return list(found)

    assert asyncio.run(scenario()) == [
        [],
        ["hall.panel"],
        [("node_degraded", True)],
    ]


def test_a_device_away_after_a_restart_alerts_nobody(tmp_path: Path) -> None:
    """No push, and degraded on screen only once the floor has passed.

    A restart starts every device node without its device, which comes back
    within seconds, and a rule on every node's health is what sends phones a
    push.
    """
    controller = _controller(tmp_path)
    events: list[dict] = []
    original = controller._publish
    controller._publish = lambda event: (events.append(event), original(event))  # type: ignore[method-assign]
    sent: list[Alert] = []
    alerts = AlertManager(
        EventBus(),
        AlertsConfig(
            channels=[Channel(name="phone", kind="ntfy", config={"topic": "t"})],
            rules=[Rule(events=["node_health"], channels=["phone"])],
        ),
    )

    async def capture(channel: Channel, alert: Alert) -> None:
        sent.append(alert)

    alerts.send = capture  # type: ignore[method-assign]

    async def scenario() -> list[list[str]]:
        await controller.reload()  # the restart: the device is not back yet
        surfaced = [[e.id for e in controller.unhealthy_nodes(health="degraded")]]
        presence.opened("wall")
        presence.closed("wall")  # and it drops again
        surfaced.append([e.id for e in controller.unhealthy_nodes(health="degraded")])
        controller.loaded["hall.panel"].health_since -= HEALTH_FLOOR
        surfaced.append([e.id for e in controller.unhealthy_nodes(health="degraded")])
        for event in events:
            await alerts.handle(event)
        await controller._teardown()
        return surfaced

    assert asyncio.run(scenario()) == [[], [], ["hall.panel"]]
    assert [e["health"] for e in events if e["type"] == "node_health"] == [
        "degraded",
        "ok",
        "degraded",
    ]
    assert sent == []
    presence.forget("wall")


def test_a_device_gone_for_the_grace_reads_false(
    tmp_path: Path, monkeypatch: pytest.MonkeyPatch
) -> None:
    """A flag such as `person` stops saying someone is there once the device
    has been away for the grace, and a device back in time keeps it."""
    from fluksio.flow.nodes import device as device_node

    monkeypatch.setattr(device_node, "OFFLINE_GRACE_S", 0.1)
    controller = _controller(tmp_path)

    def bell() -> object:
        return controller.values("hall")["hall.bell"]["value"]

    async def scenario() -> list[object]:
        await controller.reload()
        presence.opened("wall")
        controller.publish_message("hall.bell", True)
        seen = [bell()]
        # Back within the grace: nothing changes.
        presence.closed("wall")
        presence.opened("wall")
        await asyncio.sleep(0.25)
        seen.append(bell())
        # Away for good.
        presence.closed("wall")
        await asyncio.sleep(0.05)
        seen.append(bell())
        await asyncio.sleep(0.25)
        seen.append(bell())
        # What reads it hears so too.
        seen.append(controller.values("hall")["hall.rung"]["value"])
        await controller._teardown()
        presence.forget("wall")
        return seen

    assert asyncio.run(scenario()) == [True, True, True, False, False]