"""Unit tests for StaleSensor.

Uses object.__new__ to bypass HA entity setup — valid because is_on only
reads entry.options, coordinator.data timestamps, and dt_util.utcnow().
"""
from datetime import datetime, timedelta, timezone
from unittest.mock import MagicMock, patch

import pytest

from custom_components.room_cal_ha.binary_sensor import StaleSensor
from custom_components.room_cal_ha.coordinator import CoordinatorData
from custom_components.room_cal_ha.const import (
  CONF_REFRESH_INTERVAL,
  CONF_SYNC_MODE,
  DEFAULT_REFRESH_INTERVAL,
  SYNC_MODE_CALDAV,
  SYNC_MODE_MANUAL,
)
from custom_components.room_cal_ha.models import ReservationData


_NOW = datetime(2026, 6, 22, 12, 0, 0, tzinfo=timezone.utc)


def _sensor(sync_mode=SYNC_MODE_CALDAV, interval=DEFAULT_REFRESH_INTERVAL, current_ts=None, next_ts=None):
  s = object.__new__(StaleSensor)
  s._entry = MagicMock()
  s._entry.options = {CONF_SYNC_MODE: sync_mode, CONF_REFRESH_INTERVAL: interval}
  coord = MagicMock()
  coord.data = CoordinatorData(
    current=ReservationData(),
    next=ReservationData(),
    current_last_refresh=current_ts,
    next_last_refresh=next_ts,
  )
  s.coordinator = coord
  return s


# ---------------------------------------------------------------------------
# Manual mode — always None
# ---------------------------------------------------------------------------

def test_stale_sensor_manual_mode_returns_none():
  s = _sensor(sync_mode=SYNC_MODE_MANUAL)
  with patch("custom_components.room_cal_ha.binary_sensor.dt_util.utcnow", return_value=_NOW):
    assert s.is_on is None


# ---------------------------------------------------------------------------
# CalDAV mode — fresh timestamps
# ---------------------------------------------------------------------------

def test_stale_sensor_fresh_timestamps_returns_false():
  recent = _NOW - timedelta(minutes=5)
  s = _sensor(current_ts=recent, next_ts=recent, interval=15)
  with patch("custom_components.room_cal_ha.binary_sensor.dt_util.utcnow", return_value=_NOW):
    assert s.is_on is False


# ---------------------------------------------------------------------------
# CalDAV mode — stale / missing timestamps
# ---------------------------------------------------------------------------

def test_stale_sensor_none_current_ts_returns_true():
  recent = _NOW - timedelta(minutes=5)
  s = _sensor(current_ts=None, next_ts=recent, interval=15)
  with patch("custom_components.room_cal_ha.binary_sensor.dt_util.utcnow", return_value=_NOW):
    assert s.is_on is True


def test_stale_sensor_none_next_ts_returns_true():
  recent = _NOW - timedelta(minutes=5)
  s = _sensor(current_ts=recent, next_ts=None, interval=15)
  with patch("custom_components.room_cal_ha.binary_sensor.dt_util.utcnow", return_value=_NOW):
    assert s.is_on is True


def test_stale_sensor_both_ts_none_returns_true():
  s = _sensor(current_ts=None, next_ts=None, interval=15)
  with patch("custom_components.room_cal_ha.binary_sensor.dt_util.utcnow", return_value=_NOW):
    assert s.is_on is True


def test_stale_sensor_expired_current_ts_returns_true():
  # interval=15 → threshold=30 min; set current 31 min ago
  stale = _NOW - timedelta(minutes=31)
  fresh = _NOW - timedelta(minutes=5)
  s = _sensor(current_ts=stale, next_ts=fresh, interval=15)
  with patch("custom_components.room_cal_ha.binary_sensor.dt_util.utcnow", return_value=_NOW):
    assert s.is_on is True


def test_stale_sensor_exactly_at_threshold_is_not_stale():
  # Exactly 2x interval is NOT stale (uses strict >)
  threshold = _NOW - timedelta(minutes=30)
  s = _sensor(current_ts=threshold, next_ts=threshold, interval=15)
  with patch("custom_components.room_cal_ha.binary_sensor.dt_util.utcnow", return_value=_NOW):
    assert s.is_on is False


def test_stale_sensor_custom_interval():
  # interval=5 → threshold=10 min; set both 9 min ago → fresh
  recent = _NOW - timedelta(minutes=9)
  s = _sensor(current_ts=recent, next_ts=recent, interval=5)
  with patch("custom_components.room_cal_ha.binary_sensor.dt_util.utcnow", return_value=_NOW):
    assert s.is_on is False