"""Rain Bird irrigation calendar."""

from __future__ import annotations

from datetime import datetime
import logging

from homeassistant.components.calendar import CalendarEntity, CalendarEvent
from homeassistant.config_entries import ConfigEntry
from homeassistant.core import HomeAssistant
from homeassistant.exceptions import HomeAssistantError
from homeassistant.helpers.device_registry import DeviceInfo
from homeassistant.helpers.entity_platform import AddEntitiesCallback
from homeassistant.helpers.update_coordinator import CoordinatorEntity
from homeassistant.util import dt as dt_util

from .const import DOMAIN
from .coordinator import RainbirdScheduleUpdateCoordinator

_LOGGER = logging.getLogger(__name__)


async def async_setup_entry(
    hass: HomeAssistant,
    config_entry: ConfigEntry,
    async_add_entities: AddEntitiesCallback,
) -> None:
    """Set up entry for a Rain Bird irrigation calendar."""
    data = hass.data[DOMAIN][config_entry.entry_id]
    if not data.model_info.model_info.max_programs:
        return

    async_add_entities(
        [
            RainBirdCalendarEntity(
                data.schedule_coordinator,
                data.coordinator.unique_id,
                data.coordinator.device_info,
                data.coordinator.device_name,
            )
        ]
    )


class RainBirdCalendarEntity(
    CoordinatorEntity[RainbirdScheduleUpdateCoordinator], CalendarEntity
):
    """A calendar event entity."""

    _attr_has_entity_name = True
    _attr_name: str | None = None
    _attr_translation_key = "calendar"

    def __init__(
        self,
        coordinator: RainbirdScheduleUpdateCoordinator,
        unique_id: str | None,
        device_info: DeviceInfo | None,
        device_name: str,
    ) -> None:
        """Create the Calendar event device."""
        super().__init__(coordinator)
        self._event: CalendarEvent | None = None
        if unique_id is not None:
            self._attr_unique_id = unique_id
            self._attr_device_info = device_info
        else:
            self._attr_name = device_name

    @property
    def event(self) -> CalendarEvent | None:
        """Return the next upcoming event."""
        schedule = self.coordinator.data
        if not schedule:
            return None
        cursor = schedule.timeline_tz(dt_util.DEFAULT_TIME_ZONE).active_after(
            dt_util.now()
        )
        program_event = next(cursor, None)
        if not program_event:
            return None
        return CalendarEvent(
            summary=program_event.program_id.name,
            start=dt_util.as_local(program_event.start),
            end=dt_util.as_local(program_event.end),
            rrule=program_event.rrule_str,
        )

    async def async_get_events(
        self, hass: HomeAssistant, start_date: datetime, end_date: datetime
    ) -> list[CalendarEvent]:
        """Get all events in a specific time frame."""
        schedule = self.coordinator.data
        if not schedule:
            raise HomeAssistantError(
                "Unable to get events: No data from controller yet"
            )
        cursor = schedule.timeline_tz(start_date.tzinfo).overlapping(
            start_date,
            end_date,
        )
        return [
            CalendarEvent(
                summary=program_event.program_id.name,
                start=dt_util.as_local(program_event.start),
                end=dt_util.as_local(program_event.end),
                rrule=program_event.rrule_str,
            )
            for program_event in cursor
        ]

    async def async_added_to_hass(self) -> None:
        """When entity is added to hass."""
        await super().async_added_to_hass()

        # We do not ask for an update with async_add_entities()
        # because it will update disabled entities. This is started as a
        # task to let it sync in the background without blocking startup
        self.coordinator.config_entry.async_create_background_task(
            self.hass,
            self.coordinator.async_request_refresh(),
            "rainbird.calendar-refresh",
        )