"""Watcher-level tests for scale-to-zero: the idle watcher's dormant sequence and
the arm-gate wiring, exercised against the real GatewayRunner methods bound onto
a lightweight stand-in (booting a full gateway is unnecessary for this logic and
would be slow/flaky).

These cover the parts gateway/test_scale_to_zero.py (pure helpers) can't: that
the watcher calls the relay adapter's go_dormant() exactly when idle+armed,
respects the cooldown, and skips when busy — the F7/D3 + D12 behaviour.
"""

from __future__ import annotations

import asyncio
import time

import pytest

from gateway.run import GatewayRunner


class _FakeRelayAdapter:
    def __init__(self):
        self.go_dormant_calls = 0

    async def go_dormant(self):
        self.go_dormant_calls += 1
        return True


def _runner_with(monkeypatch, *, idle, armed_adapter=True, can_self_suspend=True):
    """Build a GatewayRunner without booting it, stubbing just what the watcher
    touches. Real methods (_scale_to_zero_is_idle composition, the watcher body)
    run; only their dependencies are stubbed.

    `can_self_suspend` stands in for the platform: True is Fly (an in-machine
    suspend API exists, so quiescing is followed by a freeze), False is anywhere
    the platform suspends on its own timer. The watcher only quiesces in the
    first case, so this defaults True to keep the existing cases on that path.
    """
    r = GatewayRunner.__new__(GatewayRunner)
    r._running = True
    r._scale_to_zero_cooldown_until = 0.0
    r._scale_to_zero_no_suspend_logged = False
    r._last_inbound_at = time.time()
    r._running_agents = {}
    r._background_tasks = set()
    adapter = _FakeRelayAdapter() if armed_adapter else None

    monkeypatch.setattr(r, "_scale_to_zero_is_idle", lambda: idle, raising=False)
    monkeypatch.setattr(r, "_relay_adapter_for_dormancy", lambda: adapter, raising=False)
    monkeypatch.setattr(r, "_scale_to_zero_idle_timeout_seconds", lambda: 300.0, raising=False)
    monkeypatch.setattr(r, "_update_runtime_status", lambda *a, **k: None, raising=False)
    monkeypatch.setattr(
        "gateway.scale_to_zero.self_suspend_available",
        lambda *a, **k: can_self_suspend,
    )
    return r, adapter


@pytest.mark.asyncio
async def test_watcher_does_not_quiesce_when_the_platform_owns_the_suspend(
    monkeypatch,
):
    """Quiescing cannot help when the platform owns the freeze, and the reconnect
    that follows the socket close undoes the flip, so the destination ends up
    unflipped when the freeze lands.
    """
    r, adapter = _runner_with(monkeypatch, idle=True, can_self_suspend=False)
    suspends = []
    monkeypatch.setattr(
        r,
        "_scale_to_zero_self_suspend",
        lambda *a, **k: suspends.append(1),
        raising=False,
    )

    task = asyncio.create_task(r._scale_to_zero_watcher(interval=0.01))
    await asyncio.sleep(0.1)
    r._running = False
    await asyncio.wait_for(task, timeout=2)

    assert adapter.go_dormant_calls == 0, "must not flip/close on a platform-timed suspend"
    assert suspends == []
    # No cooldown either: nothing was driven, so the next tick is free to act
    # the moment the platform picture changes.
    assert r._scale_to_zero_cooldown_until == 0.0
    assert r._scale_to_zero_no_suspend_logged is True


@pytest.mark.asyncio
async def test_watcher_goes_dormant_when_idle(monkeypatch):
    r, adapter = _runner_with(monkeypatch, idle=True)
    # Run one iteration: stop after the first sleep so the loop exits cleanly.
    task = asyncio.create_task(r._scale_to_zero_watcher(interval=0.01))
    await asyncio.sleep(0.1)
    r._running = False
    await asyncio.wait_for(task, timeout=2)
    assert adapter.go_dormant_calls >= 1
    # After driving dormant, a re-arm cooldown is set (0.F).
    assert r._scale_to_zero_cooldown_until > time.time()


    # No exception, loop exits cleanly — nothing to assert beyond survival.


def test_bg_work_blocks_idle_via_background_tasks(monkeypatch):
    """_scale_to_zero_has_live_background_work() reports True when a tracked
    background task is still live (D3/F7) — the guard that keeps a gateway with
    an in-flight backgrounded subagent/terminal awake."""
    r = GatewayRunner.__new__(GatewayRunner)

    async def _never():
        await asyncio.sleep(0.2)

    loop = asyncio.new_event_loop()
    try:
        t = loop.create_task(_never())
        r._background_tasks = {t}
        # process_registry has nothing active in this fresh process.
        assert r._scale_to_zero_has_live_background_work() is True
        t.cancel()
    finally:
        loop.run_until_complete(asyncio.gather(t, return_exceptions=True))
        loop.close()


def test_real_inbound_after_dormancy_restores_running_status(monkeypatch):
    """Once a dormant gateway receives real inbound after wake, the runtime
    lifecycle must not remain stuck in the watcher-written `draining` state."""
    r = GatewayRunner.__new__(GatewayRunner)
    r._last_inbound_at = 0.0
    r._scale_to_zero_cooldown_until = time.time() + 60.0
    status_updates = []
    monkeypatch.setattr(
        r,
        "_update_runtime_status",
        lambda state=None, *a, **k: status_updates.append(state),
        raising=False,
    )

    r._scale_to_zero_note_real_inbound()

    assert r._last_inbound_at > 0.0
    assert status_updates == ["running"]


# ── _scale_to_zero_should_arm: the CALL SITE feeds config.platforms (the F25 bug) ──
#
# config.platforms is pre-seeded with a DISABLED placeholder PlatformConfig for every
# known platform, so list(config.platforms.keys()) is always the full ~20-entry catalog
# regardless of what the instance runs. The arm check must filter to ENABLED platforms
# (mirroring the connect loop) before asking messaging_is_relay_only_or_absent — passing
# the bare placeholder keys made it see disabled `discord`/`telegram`/… as live direct
# platforms and refuse to arm on a real relay-only instance. The pure-helper tests in
# test_scale_to_zero.py pass bare names so they never exercised this call site.


def _arm_runner(monkeypatch, platform_states, *, enabled=True, wake_url="https://wake.example"):
    """Build a GatewayRunner stand-in whose config.platforms mirrors a real load:
    `platform_states` is {Platform: enabled_bool}; everything runs the REAL
    _scale_to_zero_should_arm. Only the env flag + wake_url resolution are stubbed."""
    from types import SimpleNamespace

    from gateway.config import PlatformConfig

    r = GatewayRunner.__new__(GatewayRunner)
    platforms = {p: PlatformConfig(enabled=en) for p, en in platform_states.items()}
    r.config = SimpleNamespace(platforms=platforms)

    monkeypatch.setattr("gateway.scale_to_zero.scale_to_zero_enabled", lambda *a, **k: enabled)
    monkeypatch.setattr("gateway.relay.relay_wake_url", lambda: wake_url)
    return r


def test_arm_true_for_relay_only_with_disabled_placeholders(monkeypatch):
    """The F25 regression test: relay ENABLED, every other platform present but
    DISABLED (the real load_gateway_config() shape). Must arm — the disabled
    placeholders must NOT count as live direct-socket platforms."""
    from gateway.platforms.base import Platform

    r = _arm_runner(
        monkeypatch,
        {
            Platform.TELEGRAM: False,
            Platform.DISCORD: False,
            Platform.SLACK: False,
            Platform.MATRIX: False,
            Platform.RELAY: True,
        },
    )
    assert r._scale_to_zero_should_arm() is True


def test_no_arm_when_a_direct_platform_is_actually_enabled(monkeypatch):
    """A genuinely-enabled direct-socket platform (real Discord token) DOES disarm —
    the filter must not over-broaden to 'ignore everything but relay'."""
    from gateway.platforms.base import Platform

    r = _arm_runner(
        monkeypatch,
        {Platform.DISCORD: True, Platform.RELAY: True},
    )
    assert r._scale_to_zero_should_arm() is False



# ── the self-suspend step: fires only after a clean quiesce, in order ─────────
#
# The gateway owns the suspend (Fly Proxy autostop is inbound-only/job-blind and
# no longer held open by outbound sockets), so the watcher must (a) suspend only
# AFTER go_dormant succeeded — the relay flip precedes the freeze, closing the
# buffered-event black hole — and (b) never suspend when the quiesce failed or
# inbound landed mid-quiesce.


@pytest.mark.asyncio
async def test_watcher_self_suspends_after_dormant(monkeypatch):
    r, adapter = _runner_with(monkeypatch, idle=True)
    calls = []

    async def fake_suspend():
        calls.append(("suspend", adapter.go_dormant_calls))
        r._running = False  # stop the loop after the first full sequence

    monkeypatch.setattr(r, "_scale_to_zero_self_suspend", fake_suspend, raising=False)
    task = asyncio.create_task(r._scale_to_zero_watcher(interval=0.01))
    await asyncio.wait_for(task, timeout=2)
    # Suspend fired exactly once, and only AFTER go_dormant ran (flip-before-freeze).
    assert calls == [("suspend", 1)]


@pytest.mark.asyncio
async def test_watcher_skips_suspend_when_dormant_fails(monkeypatch):
    r, adapter = _runner_with(monkeypatch, idle=True)

    async def broken_dormant():
        raise RuntimeError("quiesce failed")

    adapter.go_dormant = broken_dormant
    suspend_calls = []

    async def fake_suspend():
        suspend_calls.append(1)

    monkeypatch.setattr(r, "_scale_to_zero_self_suspend", fake_suspend, raising=False)
    task = asyncio.create_task(r._scale_to_zero_watcher(interval=0.01))
    await asyncio.sleep(0.1)
    r._running = False
    await asyncio.wait_for(task, timeout=2)
    # A failed quiesce means an UNFLIPPED relay — suspending would black-hole
    # inbound events. Must stay awake.
    assert suspend_calls == []


@pytest.mark.asyncio
async def test_watcher_skips_suspend_when_inbound_lands_mid_quiesce(monkeypatch):
    r, adapter = _runner_with(monkeypatch, idle=True)
    # First idle check (loop gate) True, second (post-quiesce re-check) False.
    reads = iter([True, False, False, False, False, False])
    monkeypatch.setattr(
        r, "_scale_to_zero_is_idle", lambda: next(reads, False), raising=False
    )
    suspend_calls = []

    async def fake_suspend():
        suspend_calls.append(1)

    monkeypatch.setattr(r, "_scale_to_zero_self_suspend", fake_suspend, raising=False)
    task = asyncio.create_task(r._scale_to_zero_watcher(interval=0.01))
    await asyncio.sleep(0.15)
    r._running = False
    await asyncio.wait_for(task, timeout=2)
    assert adapter.go_dormant_calls == 1
    assert suspend_calls == []


@pytest.mark.asyncio
async def test_self_suspend_noop_off_fly(monkeypatch):
    """Off-Fly (no flaps socket/identity) the helper is a silent no-op —
    dormancy without platform suspend, never an error."""
    r = GatewayRunner.__new__(GatewayRunner)
    monkeypatch.setattr(
        "gateway.scale_to_zero.self_suspend_available", lambda *a, **k: False
    )
    called = []
    monkeypatch.setattr(
        "gateway.scale_to_zero.suspend_self",
        lambda *a, **k: called.append(1) or True,
    )
    await r._scale_to_zero_self_suspend()
    assert called == []


# ── non-messaging platforms must not disarm (the api_server-key regression) ──
#
# The Docker stage2 hook now generates API_SERVER_KEY for every container, and
# key presence force-enables the api_server platform (gateway/config.py). The
# arm gate counted every enabled platform, so `api_server` (a loopback
# listener, not a messaging socket) made messaging_is_relay_only_or_absent
# False on EVERY hosted instance — silently disarming scale-to-zero. The gate
# must only count messaging platforms (excluding LOCAL/API_SERVER/WEBHOOK,
# mirroring _connect_platforms' messaging_platforms exclusion set).


def test_arm_true_with_api_server_enabled(monkeypatch):
    from gateway.platforms.base import Platform

    r = _arm_runner(
        monkeypatch,
        {
            Platform.RELAY: True,
            Platform.API_SERVER: True,
            Platform.TELEGRAM: False,
        },
    )
    assert r._scale_to_zero_should_arm() is True


def test_arm_true_with_all_non_messaging_surfaces_enabled(monkeypatch):
    from gateway.platforms.base import Platform

    r = _arm_runner(
        monkeypatch,
        {
            Platform.RELAY: True,
            Platform.API_SERVER: True,
            Platform.WEBHOOK: True,
            Platform.LOCAL: True,
        },
    )
    assert r._scale_to_zero_should_arm() is True


def test_direct_platform_still_disarms_alongside_api_server(monkeypatch):
    """The messaging-only filter must not over-broaden: a genuinely enabled
    direct-socket platform still disarms even with api_server also enabled."""
    from gateway.platforms.base import Platform

    r = _arm_runner(
        monkeypatch,
        {
            Platform.RELAY: True,
            Platform.API_SERVER: True,
            Platform.DISCORD: True,
        },
    )
    assert r._scale_to_zero_should_arm() is False


# ── supervised watchers must NOT count as live background work (staging bug) ──
#
# _spawn_supervised parks every permanent watcher task (session-expiry, kanban,
# reconnect, the scale-to-zero watcher ITSELF, ...) in _background_tasks. The
# bg-work check counted them, so an armed gateway considered itself busy
# forever and never went dormant — verified live on staging 2026-08-12 (armed
# at 05:25, fully idle 25+ min, zero "going dormant" lines). Fly's coarse
# autostop masked this until the gateway took ownership of the suspend.
# These tests exercise the REAL _spawn_supervised path — the earlier tests
# stubbed _background_tasks and missed the call site (same trap as F25).


@pytest.mark.asyncio
async def test_supervised_watchers_do_not_block_idle():
    r = GatewayRunner.__new__(GatewayRunner)
    r._running = True
    r._background_tasks = set()

    async def _forever():
        await asyncio.sleep(3600)

    # Spawn like production does — through _spawn_supervised.
    for name in ("session_expiry", "kanban", "scale_to_zero_watcher"):
        r._spawn_supervised(lambda: _forever(), name)
    await asyncio.sleep(0)  # let tasks start
    try:
        assert r._scale_to_zero_has_live_background_work() is False
    finally:
        for t in r._background_tasks:
            t.cancel()
        await asyncio.gather(*r._background_tasks, return_exceptions=True)


@pytest.mark.asyncio
async def test_transient_background_task_still_blocks_idle():
    """A plain (untagged) task in _background_tasks — startup-resume events,
    ad-hoc work — must still count as live background work."""
    r = GatewayRunner.__new__(GatewayRunner)
    r._running = True

    async def _work():
        await asyncio.sleep(3600)

    t = asyncio.create_task(_work())
    r._background_tasks = {t}
    try:
        assert r._scale_to_zero_has_live_background_work() is True
    finally:
        t.cancel()
        await asyncio.gather(t, return_exceptions=True)


@pytest.mark.asyncio
async def test_done_supervised_watcher_is_ignored_either_way():
    r = GatewayRunner.__new__(GatewayRunner)
    r._running = True

    async def _quick():
        return None

    t = asyncio.create_task(_quick())
    await t
    r._background_tasks = {t}
    assert r._scale_to_zero_has_live_background_work() is False


# ── permanent tasks spawned OUTSIDE _spawn_supervised must also be tagged ──
#
# _loop_heartbeat_task and _heartbeat_poll_task are both infinite while-True
# loops added to _background_tasks via plain asyncio.create_task() + manual
# add(), NOT through _spawn_supervised — so they were untagged and defeated
# the fix above: _loop_heartbeat_task starts unconditionally on every
# gateway boot (start()), which would make the busy check return True
# forever regardless of the _spawn_supervised fix, on every armed instance.


@pytest.mark.asyncio
async def test_loop_heartbeat_task_does_not_block_idle():
    r = GatewayRunner.__new__(GatewayRunner)
    r._running = True
    r._background_tasks = set()
    r._loop_heartbeat_task = None
    r._gateway_started_at = time.time()

    r._start_loop_heartbeat_task()
    await asyncio.sleep(0)  # let the task start
    try:
        assert r._scale_to_zero_has_live_background_work() is False
    finally:
        r._loop_heartbeat_task.cancel()
        await asyncio.gather(r._loop_heartbeat_task, return_exceptions=True)


@pytest.mark.asyncio
async def test_heartbeat_poll_task_does_not_block_idle():
    r = GatewayRunner.__new__(GatewayRunner)
    r._running = True
    r._background_tasks = set()
    r._heartbeat_poll_task = None
    r._heartbeat_watch = {}
    r._running_agents = {}

    r._start_heartbeat_poller()
    await asyncio.sleep(0)  # let the task start
    try:
        assert r._scale_to_zero_has_live_background_work() is False
    finally:
        r._heartbeat_poll_task.cancel()
        await asyncio.gather(r._heartbeat_poll_task, return_exceptions=True)


# ── in-flight cron / API-server work must block suspend (the 10:45 near-miss) ──
#
# Cron jobs run on the scheduler's thread pool and API-server runs live on the
# adapter — both outside _running_agents (the #60432 blind spot). The idle
# predicate must consume _active_work_count() (agents + cron + api runs), or a
# suspend can freeze a cron job mid-run: observed on staging 2026-08-20, where
# is_idle held True throughout a live cron run and only tick timing saved it.


def _work_count_runner(monkeypatch, *, agents=0, cron_ids=(), api_runs=0):
    from types import SimpleNamespace

    r = GatewayRunner.__new__(GatewayRunner)
    r._running = True
    r._running_agents = {f"a{i}": object() for i in range(agents)}
    r._background_tasks = set()
    r._last_inbound_at = 0.0  # inbound-quiet for hours
    monkeypatch.setattr(
        r, "_scale_to_zero_idle_timeout_seconds", lambda: 300.0, raising=False
    )
    monkeypatch.setattr(
        "cron.scheduler.get_running_job_ids", lambda: set(cron_ids)
    )
    api_adapter = SimpleNamespace(active_agent_work_count=lambda: api_runs)
    from gateway.platforms.base import Platform

    r.adapters = {Platform.API_SERVER: api_adapter}
    return r


def test_running_cron_job_blocks_idle(monkeypatch):
    r = _work_count_runner(monkeypatch, cron_ids={"job1"})
    assert r._scale_to_zero_is_idle() is False


def test_active_api_run_blocks_idle(monkeypatch):
    r = _work_count_runner(monkeypatch, api_runs=1)
    assert r._scale_to_zero_is_idle() is False


def test_idle_true_when_all_work_sources_quiet(monkeypatch):
    r = _work_count_runner(monkeypatch)
    assert r._scale_to_zero_is_idle() is True


def test_unreadable_cron_source_fails_awake(monkeypatch):
    """A transient failure reading the cron work source must count as WORK
    (stay awake), not as idle — fail-open accounting would reopen the
    mid-job-freeze hole exactly when bookkeeping is broken."""
    r = _work_count_runner(monkeypatch)

    def _boom():
        raise RuntimeError("registry unavailable")

    monkeypatch.setattr("cron.scheduler.get_running_job_ids", _boom)
    assert r._scale_to_zero_is_idle() is False


def test_unreadable_api_source_fails_awake(monkeypatch):
    from types import SimpleNamespace

    def _boom():
        raise RuntimeError("adapter wedged")

    r = _work_count_runner(monkeypatch)
    from gateway.platforms.base import Platform

    r.adapters = {Platform.API_SERVER: SimpleNamespace(active_agent_work_count=_boom)}
    assert r._scale_to_zero_is_idle() is False


def test_missing_api_adapter_is_not_work(monkeypatch):
    """No api_server adapter at all (common: relay-only instance before the
    key existed) is a NORMAL state, not an unreadable source — must not hold
    the machine awake."""
    r = _work_count_runner(monkeypatch)
    r.adapters = {}
    assert r._scale_to_zero_is_idle() is True