from datetime import date, datetime, time

import pytest

from custom_components.room_cal_ha.models import GuestStateDiff, OverrideData, ReservationData, is_window_active, reservation_diff


# ---------------------------------------------------------------------------
# ReservationData — serialization
# ---------------------------------------------------------------------------

def test_to_dict_serializes_dates_and_times():
  res = ReservationData(
    guest_name="Alice",
    check_in_date=date(2026, 7, 1),
    check_in_time=time(14, 0),
    check_out_date=date(2026, 7, 5),
    check_out_time=time(12, 0),
    wifi_key="abc",
    door_code="1234",
  )
  d = res.to_dict()
  assert d["guest_name"] == "Alice"
  assert d["check_in_date"] == "2026-07-01"
  assert d["check_in_time"] == "14:00:00"
  assert d["check_out_date"] == "2026-07-05"
  assert d["check_out_time"] == "12:00:00"
  assert d["wifi_key"] == "abc"
  assert d["door_code"] == "1234"


def test_to_dict_none_fields_stay_none():
  res = ReservationData(guest_name=None, check_in_date=None, wifi_key=None)
  d = res.to_dict()
  assert d["guest_name"] is None
  assert d["check_in_date"] is None
  assert d["wifi_key"] is None


def test_from_dict_deserializes_iso_strings():
  d = {
    "guest_name": "Bob",
    "check_in_date": "2026-08-01",
    "check_in_time": "15:00:00",
    "check_out_date": "2026-08-04",
    "check_out_time": "11:00:00",
    "wifi_ssid": "Net",
    "wifi_key": "xyz",
    "door_code": "9876",
  }
  res = ReservationData.from_dict(d)
  assert res.guest_name == "Bob"
  assert res.check_in_date == date(2026, 8, 1)
  assert res.check_in_time == time(15, 0)
  assert res.check_out_date == date(2026, 8, 4)
  assert res.check_out_time == time(11, 0)
  assert res.wifi_key == "xyz"
  assert res.door_code == "9876"


def test_from_dict_none_fields():
  d = {
    "guest_name": None,
    "check_in_date": None,
    "check_in_time": None,
    "check_out_date": None,
    "check_out_time": None,
    "wifi_ssid": None,
    "wifi_key": None,
    "door_code": None,
  }
  res = ReservationData.from_dict(d)
  assert res.guest_name is None
  assert res.check_in_date is None
  assert res.check_in_time is None


def test_round_trip():
  original = ReservationData(
    guest_name="Carol",
    check_in_date=date(2026, 9, 10),
    check_in_time=time(14, 30),
    check_out_date=date(2026, 9, 14),
    check_out_time=time(11, 0),
    wifi_ssid="HomeNet",
    wifi_key="pw",
    door_code="0000",
  )
  assert ReservationData.from_dict(original.to_dict()) == original


# ---------------------------------------------------------------------------
# ReservationData — apply_partial
# ---------------------------------------------------------------------------

SAMPLE = ReservationData(
  guest_name="Alice",
  check_in_date=date(2026, 7, 1),
  check_in_time=time(14, 0),
  check_out_date=date(2026, 7, 5),
  check_out_time=time(12, 0),
  wifi_ssid="4114",
  wifi_key="stone",
  door_code="0472",
)


def test_apply_partial_overlays_specified_fields():
  updated = SAMPLE.apply_partial({"wifi_ssid": "GuestNet", "door_code": "9999"})
  assert updated.wifi_ssid == "GuestNet"
  assert updated.door_code == "9999"


def test_apply_partial_leaves_other_fields_unchanged():
  updated = SAMPLE.apply_partial({"door_code": "1111"})
  assert updated.guest_name == "Alice"
  assert updated.check_in_date == date(2026, 7, 1)
  assert updated.wifi_key == "stone"


def test_apply_partial_can_clear_a_field_with_none():
  updated = SAMPLE.apply_partial({"guest_name": None})
  assert updated.guest_name is None


def test_apply_partial_ignores_unknown_keys():
  updated = SAMPLE.apply_partial({"nonexistent_field": "x"})
  assert updated == SAMPLE


def test_apply_partial_empty_dict_returns_equivalent():
  updated = SAMPLE.apply_partial({})
  assert updated == SAMPLE


# ---------------------------------------------------------------------------
# ReservationData — defaults
# ---------------------------------------------------------------------------

def test_default_values():
  res = ReservationData()
  assert res.guest_name is None
  assert res.check_in_date is None
  assert res.check_in_time is None
  assert res.check_out_date is None
  assert res.check_out_time is None
  assert res.wifi_ssid is None
  assert res.wifi_key is None
  assert res.door_code is None


# ---------------------------------------------------------------------------
# OverrideData
# ---------------------------------------------------------------------------

_RES_A = ReservationData(guest_name="Alice")
_RES_B = ReservationData(guest_name="Bob")


def test_override_data_requires_current():
  o = OverrideData(current=_RES_A)
  assert o.current.guest_name == "Alice"


def test_override_data_next_defaults_to_none():
  o = OverrideData(current=_RES_A)
  assert o.next is None


def test_override_data_with_next():
  o = OverrideData(current=_RES_A, next=_RES_B)
  assert o.current.guest_name == "Alice"
  assert o.next.guest_name == "Bob"


# ---------------------------------------------------------------------------
# reservation_diff
# ---------------------------------------------------------------------------

def _res(checkin_h: int, checkout_h: int, *, wifi_key="key", wifi_ssid="ssid", door_code=None) -> ReservationData:
  """Build a reservation on 2026-07-01 with given check-in/out hours."""
  return ReservationData(
    guest_name="Guest",
    check_in_date=date(2026, 7, 1),
    check_in_time=time(checkin_h, 0),
    check_out_date=date(2026, 7, 1),
    check_out_time=time(checkout_h, 0),
    wifi_ssid=wifi_ssid,
    wifi_key=wifi_key,
    door_code=door_code,
  )


_DURING = datetime(2026, 7, 1, 15, 0)   # 15:00 — inside a 14:00–12:00 window
_BEFORE = datetime(2026, 7, 1, 12, 0)   # 12:00 — before 14:00 check-in
_AFTER  = datetime(2026, 7, 1, 22, 0)   # 22:00 — after typical check-out


def test_diff_both_inactive_returns_no_changes():
  diff = reservation_diff(None, None, _DURING)
  assert not diff.has_changes


def test_diff_old_none_new_active_returns_checkin():
  res = _res(14, 20)
  diff = reservation_diff(None, res, _DURING)
  assert diff.checkin_needed
  assert not diff.checkout_needed
  assert diff.departing is None


def test_diff_old_active_new_none_returns_checkout():
  res = _res(14, 20)
  diff = reservation_diff(res, None, _DURING)
  assert diff.checkout_needed
  assert not diff.checkin_needed
  assert diff.departing is res


def test_diff_both_elapsed_returns_no_changes():
  # Window already passed for both — time-based handler owns this transition, not diff.
  old = _res(14, 20)
  diff = reservation_diff(old, old, _AFTER)
  assert not diff.has_changes


def test_diff_backend_clears_active_reservation_returns_checkout():
  # Backend returns None while we're still inside the window → checkout needed.
  old = _res(14, 20)
  now = datetime(2026, 7, 1, 16, 0)
  diff = reservation_diff(old, None, now)
  assert diff.checkout_needed
  assert not diff.checkin_needed
  assert diff.departing is old


def test_diff_same_window_no_changes_returns_empty():
  res = _res(14, 20)
  diff = reservation_diff(res, res, _DURING)
  assert not diff.has_changes


def test_diff_same_window_wifi_key_changed():
  old = _res(14, 20, wifi_key="old-key")
  new = _res(14, 20, wifi_key="new-key")
  diff = reservation_diff(old, new, _DURING)
  assert diff.wifi_key_changed
  assert not diff.door_code_changed
  assert not diff.checkin_needed
  assert not diff.checkout_needed


def test_diff_same_window_door_code_changed():
  old = _res(14, 20, door_code="1234")
  new = _res(14, 20, door_code="5678")
  diff = reservation_diff(old, new, _DURING)
  assert diff.door_code_changed
  assert not diff.wifi_key_changed
  assert not diff.checkin_needed
  assert not diff.checkout_needed


def test_diff_same_window_no_change():
  old = _res(14, 20, wifi_key="key", door_code="1234")
  new = _res(14, 20, wifi_key="key", door_code="1234")
  diff = reservation_diff(old, new, _DURING)
  assert not diff.has_changes


def test_diff_different_window_both_active_returns_checkout_and_checkin():
  old = ReservationData(
    check_in_date=date(2026, 7, 1), check_in_time=time(14, 0),
    check_out_date=date(2026, 7, 2), check_out_time=time(12, 0),
    wifi_ssid="s", wifi_key="k",
  )
  new = ReservationData(
    check_in_date=date(2026, 7, 1), check_in_time=time(10, 0),
    check_out_date=date(2026, 7, 2), check_out_time=time(12, 0),
    wifi_ssid="s", wifi_key="k",
  )
  now = datetime(2026, 7, 1, 15, 0)  # after both check-ins
  diff = reservation_diff(old, new, now)
  assert diff.checkout_needed
  assert diff.checkin_needed
  assert diff.departing is old


def test_diff_inactive_old_becomes_active_new_returns_checkin():
  res = _res(14, 20)
  diff = reservation_diff(res, res, _BEFORE)   # same record, but we're before check-in
  # old is inactive (before window), new is inactive too → no changes
  assert not diff.has_changes


def test_diff_no_checkin_time_treated_as_inactive():
  res = ReservationData(check_in_date=date(2026, 7, 1))  # no time fields
  diff = reservation_diff(None, res, _DURING)
  assert not diff.has_changes


def test_guest_state_diff_has_changes_false_when_empty():
  assert not GuestStateDiff().has_changes


def test_guest_state_diff_has_changes_true_for_checkin():
  assert GuestStateDiff(checkin_needed=True).has_changes


# ---------------------------------------------------------------------------
# is_window_active — boundary conditions
#
# These directly guard the fix for the midnight-boundary bug where date-only
# comparisons would make a 14:00 check-in appear "active" at 00:00 that day.
# ---------------------------------------------------------------------------

def _stay(checkin_date, checkin_time, checkout_date=None, checkout_time=None) -> ReservationData:
  return ReservationData(
    check_in_date=checkin_date,
    check_in_time=checkin_time,
    check_out_date=checkout_date,
    check_out_time=checkout_time,
  )


_CHECKIN_DAY = date(2026, 7, 1)
_CHECKOUT_DAY = date(2026, 7, 5)
_CHECKIN_TIME = time(14, 0)
_CHECKOUT_TIME = time(11, 0)
_STAY = _stay(_CHECKIN_DAY, _CHECKIN_TIME, _CHECKOUT_DAY, _CHECKOUT_TIME)


def test_is_window_active_false_at_midnight_before_checkin():
  # 00:00 on check-in day — hours before the actual check-in time. This is the
  # exact scenario that triggered the midnight-boundary bug.
  midnight = datetime(_CHECKIN_DAY.year, _CHECKIN_DAY.month, _CHECKIN_DAY.day, 0, 0)
  assert is_window_active(_STAY, midnight) is False


def test_is_window_active_false_just_before_checkin():
  one_minute_before = datetime(_CHECKIN_DAY.year, _CHECKIN_DAY.month, _CHECKIN_DAY.day, 13, 59)
  assert is_window_active(_STAY, one_minute_before) is False


def test_is_window_active_true_at_checkin_time():
  at_checkin = datetime.combine(_CHECKIN_DAY, _CHECKIN_TIME)
  assert is_window_active(_STAY, at_checkin) is True


def test_is_window_active_true_during_stay():
  mid_stay = datetime(2026, 7, 3, 10, 0)
  assert is_window_active(_STAY, mid_stay) is True


def test_is_window_active_false_at_checkout_time():
  # Checkout boundary is exclusive: exactly at checkout_time → no longer active.
  at_checkout = datetime.combine(_CHECKOUT_DAY, _CHECKOUT_TIME)
  assert is_window_active(_STAY, at_checkout) is False


def test_is_window_active_true_just_before_checkout():
  one_minute_before = datetime(_CHECKOUT_DAY.year, _CHECKOUT_DAY.month, _CHECKOUT_DAY.day, 10, 59)
  assert is_window_active(_STAY, one_minute_before) is True


def test_is_window_active_false_when_no_checkin_time():
  # Date present but no time — treated as inactive (guards against date-only comparisons).
  date_only = ReservationData(check_in_date=_CHECKIN_DAY)
  assert is_window_active(date_only, datetime(_CHECKIN_DAY.year, _CHECKIN_DAY.month, _CHECKIN_DAY.day, 15, 0)) is False


def test_is_window_active_false_when_reservation_is_none():
  assert is_window_active(None, datetime(2026, 7, 1, 15, 0)) is False