"""Unit tests for the per-query watchdog verdict logic.

The grace window is the whole point: a search that has just finished is briefly
'unknown' on the librarian while its result is still in flight, and we must NOT
flag that as lost. Only a uuid that stays unknown-but-pending past the grace
window is a genuinely lost result.
"""
from librarian_watchdog import FLAG, WAIT, pending_verdict

GRACE = 45


def test_known_resets_clock_and_waits():
    action, unknown_since = pending_verdict(
        known=True, unknown_since=100.0, now=200.0, grace_seconds=GRACE
    )
    assert action == WAIT
    assert unknown_since is None  # clock reset while it's still known


def test_first_unknown_starts_grace_but_does_not_flag():
    action, unknown_since = pending_verdict(
        known=False, unknown_since=None, now=1000.0, grace_seconds=GRACE
    )
    assert action == WAIT
    assert unknown_since == 1000.0  # clock started now


def test_unknown_within_grace_keeps_waiting():
    action, unknown_since = pending_verdict(
        known=False, unknown_since=1000.0, now=1000.0 + GRACE - 1, grace_seconds=GRACE
    )
    assert action == WAIT
    assert unknown_since == 1000.0  # unchanged, still counting


def test_unknown_past_grace_flags_lost():
    action, unknown_since = pending_verdict(
        known=False, unknown_since=1000.0, now=1000.0 + GRACE, grace_seconds=GRACE
    )
    assert action == FLAG
    assert unknown_since == 1000.0


def test_recovered_to_known_after_being_unknown_resets():
    # It reappeared (e.g. requeued / status flapped): do not flag, reset.
    action, unknown_since = pending_verdict(
        known=True, unknown_since=1000.0, now=1000.0 + GRACE + 10, grace_seconds=GRACE
    )
    assert action == WAIT
    assert unknown_since is None