from __future__ import annotations

import json
from pathlib import Path
from threading import Event

from k1link.service_watchdog import (
    ConsecutiveHealthGate,
    MissionCoreSelfWatchdog,
    MissionCoreWatchdogJournal,
    MissionCoreWatchdogPolicy,
    watchdog_enabled,
)


def test_consecutive_health_gate_resets_after_recovery() -> None:
    gate = ConsecutiveHealthGate(3)

    assert gate.observe(False) is False
    assert gate.observe(False) is False
    assert gate.observe(True) is False
    assert gate.consecutive_failures == 0
    assert gate.observe(False) is False
    assert gate.observe(False) is False
    assert gate.observe(False) is True


def test_self_watchdog_escalates_a_persistently_unhealthy_process(tmp_path: Path) -> None:
    requested = Event()
    forced = Event()
    journal_path = tmp_path / "watchdog.jsonl"
    watchdog = MissionCoreSelfWatchdog(
        tmp_path,
        policy=MissionCoreWatchdogPolicy(
            startup_grace_seconds=0.01,
            probe_interval_seconds=0.01,
            probe_timeout_seconds=0.01,
            consecutive_failure_limit=2,
            graceful_shutdown_seconds=0.02,
        ),
        probe=lambda: False,
        request_shutdown=requested.set,
        force_shutdown=forced.set,
        journal=MissionCoreWatchdogJournal(journal_path),
    )

    watchdog.start()

    assert requested.wait(0.5)
    assert forced.wait(0.5)
    watchdog.stop()
    events = [json.loads(line)["event"] for line in journal_path.read_text().splitlines()]
    assert events == [
        "watchdog-started",
        "health-state-changed",
        "restart-requested",
        "restart-escalated",
        "watchdog-stopped",
    ]


def test_self_watchdog_leaves_a_healthy_process_running(tmp_path: Path) -> None:
    probed = Event()
    requested = Event()
    forced = Event()
    journal_path = tmp_path / "watchdog.jsonl"

    def healthy_probe() -> bool:
        probed.set()
        return True

    watchdog = MissionCoreSelfWatchdog(
        tmp_path,
        policy=MissionCoreWatchdogPolicy(
            startup_grace_seconds=0.01,
            probe_interval_seconds=0.01,
            probe_timeout_seconds=0.01,
            consecutive_failure_limit=2,
            graceful_shutdown_seconds=0.02,
        ),
        probe=healthy_probe,
        request_shutdown=requested.set,
        force_shutdown=forced.set,
        journal=MissionCoreWatchdogJournal(journal_path),
    )

    watchdog.start()

    assert probed.wait(0.5)
    watchdog.stop()
    assert requested.is_set() is False
    assert forced.is_set() is False
    events = [json.loads(line)["event"] for line in journal_path.read_text().splitlines()]
    assert events == [
        "watchdog-started",
        "health-state-changed",
        "watchdog-stopped",
    ]


def test_watchdog_journal_rotates_before_exceeding_bound(tmp_path: Path) -> None:
    path = tmp_path / "watchdog.jsonl"
    journal = MissionCoreWatchdogJournal(path, max_bytes=300)

    journal.append("first", payload="x" * 180)
    journal.append("second", payload="y" * 180)

    assert path.is_file()
    assert path.with_name("watchdog.jsonl.1").is_file()
    assert json.loads(path.read_text())["event"] == "second"


def test_watchdog_requires_exact_enable_marker() -> None:
    assert watchdog_enabled({"MISSIONCORE_SERVICE_WATCHDOG": "1"}) is True
    assert watchdog_enabled({"MISSIONCORE_SERVICE_WATCHDOG": "true"}) is False
    assert watchdog_enabled({}) is False