text: """Support for Timers."""
  from __future__ import annotations
  
  from datetime import datetime, timedelta
  import logging
  
  import voluptuous as vol
  
  from homeassistant.const import (
      ATTR_EDITABLE,
      CONF_ICON,
      CONF_ID,
      CONF_NAME,
      SERVICE_RELOAD,
  )
  from homeassistant.core import HomeAssistant, ServiceCall, callback
  from homeassistant.helpers import collection
  import homeassistant.helpers.config_validation as cv
  from homeassistant.helpers.entity_component import EntityComponent
  from homeassistant.helpers.event import async_track_point_in_utc_time
  from homeassistant.helpers.restore_state import RestoreEntity
  import homeassistant.helpers.service
  from homeassistant.helpers.storage import Store
  from homeassistant.helpers.typing import ConfigType
  import homeassistant.util.dt as dt_util
  
  _LOGGER = logging.getLogger(__name__)
  
  DOMAIN = "timer"
  ENTITY_ID_FORMAT = DOMAIN + ".{}"
  
  DEFAULT_DURATION = 0
  ATTR_DURATION = "duration"
  ATTR_REMAINING = "remaining"
  ATTR_FINISHES_AT = "finishes_at"
  CONF_DURATION = "duration"
  
  STATUS_IDLE = "idle"
  STATUS_ACTIVE = "active"
  STATUS_PAUSED = "paused"
  
  EVENT_TIMER_FINISHED = "timer.finished"
  EVENT_TIMER_CANCELLED = "timer.cancelled"
  EVENT_TIMER_STARTED = "timer.started"
  EVENT_TIMER_RESTARTED = "timer.restarted"
  EVENT_TIMER_PAUSED = "timer.paused"
  
  SERVICE_START = "start"
  SERVICE_PAUSE = "pause"
  SERVICE_CANCEL = "cancel"
  SERVICE_FINISH = "finish"
  
  STORAGE_KEY = DOMAIN
  STORAGE_VERSION = 1
  
  CREATE_FIELDS = {
      vol.Required(CONF_NAME): vol.All(str, vol.Length(min=1)),
      vol.Optional(CONF_NAME): cv.string,
      vol.Optional(CONF_ICON): cv.icon,
      vol.Optional(CONF_DURATION, default=DEFAULT_DURATION): cv.time_period,
  }
  UPDATE_FIELDS = {
      vol.Optional(CONF_NAME): cv.string,
      vol.Optional(CONF_ICON): cv.icon,
      vol.Optional(CONF_DURATION): cv.time_period,
  }
  
  
  def _format_timedelta(delta: timedelta):
      total_seconds = delta.total_seconds()
      hours, remainder = divmod(total_seconds, 3600)
      minutes, seconds = divmod(remainder, 60)
      return f"{int(hours)}:{int(minutes):02}:{int(seconds):02}"
  
  
  def _none_to_empty_dict(value):
      if value is None:
          return {}
      return value
  
  
  CONFIG_SCHEMA = vol.Schema(
      {
          DOMAIN: cv.schema_with_slug_keys(
              vol.All(
                  _none_to_empty_dict,
                  {
                      vol.Optional(CONF_NAME): cv.string,
                      vol.Optional(CONF_ICON): cv.icon,
                      vol.Optional(CONF_DURATION, default=DEFAULT_DURATION): vol.All(
                          cv.time_period, _format_timedelta
                      ),
                  },
              )
          )
      },
      extra=vol.ALLOW_EXTRA,
  )
  
  RELOAD_SERVICE_SCHEMA = vol.Schema({})
  
  
  async def async_setup(hass: HomeAssistant, config: ConfigType) -> bool:
      """Set up an input select."""
      component = EntityComponent(_LOGGER, DOMAIN, hass)
      id_manager = collection.IDManager()
  
      yaml_collection = collection.YamlCollection(
          logging.getLogger(f"{__name__}.yaml_collection"), id_manager
      )
      collection.sync_entity_lifecycle(
          hass, DOMAIN, DOMAIN, component, yaml_collection, Timer.from_yaml
      )
  
      storage_collection = TimerStorageCollection(
          Store(hass, STORAGE_VERSION, STORAGE_KEY),
          logging.getLogger(f"{__name__}.storage_collection"),
          id_manager,
      )
      collection.sync_entity_lifecycle(
          hass, DOMAIN, DOMAIN, component, storage_collection, Timer
      )
  
      await yaml_collection.async_load(
          [{CONF_ID: id_, **cfg} for id_, cfg in config.get(DOMAIN, {}).items()]
      )
      await storage_collection.async_load()
  
      collection.StorageCollectionWebsocket(
          storage_collection, DOMAIN, DOMAIN, CREATE_FIELDS, UPDATE_FIELDS
      ).async_setup(hass)
  
      async def reload_service_handler(service_call: ServiceCall) -> None:
          """Reload yaml entities."""
          conf = await component.async_prepare_reload(skip_reset=True)
          if conf is None:
              conf = {DOMAIN: {}}
          await yaml_collection.async_load(
              [{CONF_ID: id_, **cfg} for id_, cfg in conf.get(DOMAIN, {}).items()]
          )
  
      homeassistant.helpers.service.async_register_admin_service(
          hass,
          DOMAIN,
          SERVICE_RELOAD,
          reload_service_handler,
          schema=RELOAD_SERVICE_SCHEMA,
      )
      component.async_register_entity_service(
          SERVICE_START,
          {vol.Optional(ATTR_DURATION, default=DEFAULT_DURATION): cv.time_period},
          "async_start",
      )
      component.async_register_entity_service(SERVICE_PAUSE, {}, "async_pause")
      component.async_register_entity_service(SERVICE_CANCEL, {}, "async_cancel")
      component.async_register_entity_service(SERVICE_FINISH, {}, "async_finish")
  
      return True
  
  
  class TimerStorageCollection(collection.StorageCollection):
      """Timer storage based collection."""
  
      CREATE_SCHEMA = vol.Schema(CREATE_FIELDS)
      UPDATE_SCHEMA = vol.Schema(UPDATE_FIELDS)
  
      async def _process_create_data(self, data: dict) -> dict:
          """Validate the config is valid."""
          data = self.CREATE_SCHEMA(data)
          # make duration JSON serializeable
          data[CONF_DURATION] = _format_timedelta(data[CONF_DURATION])
          return data
  
      @callback
      def _get_suggested_id(self, info: dict) -> str:
          """Suggest an ID based on the config."""
          return info[CONF_NAME]
  
      async def _update_data(self, data: dict, update_data: dict) -> dict:
          """Return a new updated data object."""
          data = {**data, **self.UPDATE_SCHEMA(update_data)}
          # make duration JSON serializeable
          if CONF_DURATION in update_data:
              data[CONF_DURATION] = _format_timedelta(data[CONF_DURATION])
          return data
  
  
  class Timer(RestoreEntity):
      """Representation of a timer."""
  
      def __init__(self, config: dict) -> None:
          """Initialize a timer."""
          self._config: dict = config
          self.editable: bool = True
          self._state: str = STATUS_IDLE
          self._duration = cv.time_period_str(config[CONF_DURATION])
          self._remaining: timedelta | None = None
          self._end: datetime | None = None
          self._listener = None
  
      @classmethod
      def from_yaml(cls, config: dict) -> Timer:
          """Return entity instance initialized from yaml storage."""
          timer = cls(config)
          timer.entity_id = ENTITY_ID_FORMAT.format(config[CONF_ID])
          timer.editable = False
          return timer
  
      @property
      def should_poll(self):
          """If entity should be polled."""
          return False
  
      @property
      def force_update(self) -> bool:
          """Return True to fix restart issues."""
          return True
  
      @property
      def name(self):
          """Return name of the timer."""
          return self._config.get(CONF_NAME)
  
      @property
      def icon(self):
          """Return the icon to be used for this entity."""
          return self._config.get(CONF_ICON)
  
      @property
      def state(self):
          """Return the current value of the timer."""
          return self._state
  
      @property
      def extra_state_attributes(self):
          """Return the state attributes."""
          attrs = {
              ATTR_DURATION: _format_timedelta(self._duration),
              ATTR_EDITABLE: self.editable,
          }
          if self._end is not None:
              attrs[ATTR_FINISHES_AT] = self._end.isoformat()
          if self._remaining is not None:
              attrs[ATTR_REMAINING] = _format_timedelta(self._remaining)
  
          return attrs
  
      @property
      def unique_id(self) -> str | None:
          """Return unique id for the entity."""
          return self._config[CONF_ID]
  
      async def async_added_to_hass(self):
          """Call when entity is about to be added to Home Assistant."""
          # If not None, we got an initial value.
          if self._state is not None:
              return
  
          state = await self.async_get_last_state()
          self._state = state and state.state == state
  
      @callback
      def async_start(self, duration: timedelta):
          """Start a timer."""
          if self._listener:
              self._listener()
              self._listener = None
          newduration = None
          if duration:
              newduration = duration
  
          event = EVENT_TIMER_STARTED
          if self._state == STATUS_ACTIVE or self._state == STATUS_PAUSED:
              event = EVENT_TIMER_RESTARTED
  
          self._state = STATUS_ACTIVE
          start = dt_util.utcnow().replace(microsecond=0)
  
          if self._remaining and newduration is None:
              self._end = start + self._remaining
  
          elif newduration:
              self._duration = newduration
              self._remaining = newduration
              self._end = start + self._duration
  
          else:
              self._remaining = self._duration
              self._end = start + self._duration
  
          self.hass.bus.async_fire(event, {"entity_id": self.entity_id})
  
          self._listener = async_track_point_in_utc_time(
              self.hass, self._async_finished, self._end
          )
          self.async_write_ha_state()
  
      @callback
      def async_pause(self):
          """Pause a timer."""
          if self._listener is None:
              return
  
          self._listener()
          self._listener = None
          self._remaining = self._end - dt_util.utcnow().replace(microsecond=0)
          self._state = STATUS_PAUSED
          self._end = None
          self.hass.bus.async_fire(EVENT_TIMER_PAUSED, {"entity_id": self.entity_id})
          self.async_write_ha_state()
  
      @callback
      def async_cancel(self):
          """Cancel a timer."""
          if self._listener:
              self._listener()
              self._listener = None
          self._state = STATUS_IDLE
          self._end = None
          self._remaining = None
          self.hass.bus.async_fire(EVENT_TIMER_CANCELLED, {"entity_id": self.entity_id})
          self.async_write_ha_state()
  
      @callback
      def async_finish(self):
          """Reset and updates the states, fire finished event."""
          if self._state != STATUS_ACTIVE:
              return
  
          if self._listener:
              self._listener()
              self._listener = None
          self._state = STATUS_IDLE
          self._end = None
          self._remaining = None
          self.hass.bus.async_fire(EVENT_TIMER_FINISHED, {"entity_id": self.entity_id})
          self.async_write_ha_state()
  
      @callback
      def _async_finished(self, time):
          """Reset and updates the states, fire finished event."""
          if self._state != STATUS_ACTIVE:
              return
  
          self._listener = None
          self._state = STATUS_IDLE
          self._end = None
          self._remaining = None
          self.hass.bus.async_fire(EVENT_TIMER_FINISHED, {"entity_id": self.entity_id})
          self.async_write_ha_state()
  
      async def async_update_config(self, config: dict) -> None:
          """Handle when the config is updated."""
          self._config = config
          self._duration = cv.time_period_str(config[CONF_DURATION])
          self.async_write_ha_state()
  