HomeAssistantVS/custom_components/powercalc/sensors/group/custom.py

from __future__ import annotations

from abc import abstractmethod
from collections.abc import Callable
from datetime import datetime, timedelta
from decimal import Decimal
import logging
import time
from typing import Any

from homeassistant.components.sensor import (
    DOMAIN as SENSOR_DOMAIN,
    RestoreSensor,
    SensorDeviceClass,
    SensorEntity,
    SensorStateClass,
)
from homeassistant.config_entries import ConfigEntry
from homeassistant.const import (
    ATTR_ENTITY_ID,
    ATTR_UNIT_OF_MEASUREMENT,
    CONF_DOMAIN,
    CONF_ENTITY_ID,
    CONF_NAME,
    CONF_UNIQUE_ID,
    EVENT_HOMEASSISTANT_STOP,
    STATE_UNAVAILABLE,
    STATE_UNKNOWN,
    UnitOfEnergy,
    UnitOfPower,
)
from homeassistant.core import (
    CALLBACK_TYPE,
    Event,
    HomeAssistant,
    State,
    callback,
)
from homeassistant.exceptions import HomeAssistantError
from homeassistant.helpers import entity_registry as er, start
from homeassistant.helpers.entity import Entity
from homeassistant.helpers.event import (
    EventStateChangedData,
    async_call_later,
    async_track_state_change_event,
    async_track_time_interval,
)
from homeassistant.helpers.json import JSONEncoder
from homeassistant.helpers.singleton import singleton
from homeassistant.helpers.storage import Store

from custom_components.powercalc.analytics.analytics import collect_analytics
from custom_components.powercalc.const import (
    ATTR_ENTITIES,
    ATTR_IS_GROUP,
    ATTR_MEMBERS,
    ATTR_STATE,
    CONF_ALL,
    CONF_AREA,
    CONF_CREATE_ENERGY_SENSOR,
    CONF_CREATE_GROUP,
    CONF_DISABLE_EXTENDED_ATTRIBUTES,
    CONF_ENERGY_SENSOR_PRECISION,
    CONF_ENERGY_SENSOR_UNIT_PREFIX,
    CONF_EXCLUDE_ENTITIES,
    CONF_FLOOR,
    CONF_FORCE_CALCULATE_GROUP_ENERGY,
    CONF_GROUP_ENERGY_ENTITIES,
    CONF_GROUP_ENERGY_START_AT_ZERO,
    CONF_GROUP_ENERGY_UPDATE_INTERVAL,
    CONF_GROUP_MEMBER_DEVICES,
    CONF_GROUP_MEMBER_SENSORS,
    CONF_GROUP_POWER_ENTITIES,
    CONF_GROUP_POWER_UPDATE_INTERVAL,
    CONF_GROUP_TYPE,
    CONF_HIDE_MEMBERS,
    CONF_IGNORE_UNAVAILABLE_STATE,
    CONF_INCLUDE_NON_POWERCALC_SENSORS,
    CONF_POWER_SENSOR_PRECISION,
    CONF_SENSOR_TYPE,
    CONF_SUB_GROUPS,
    CONF_UTILITY_METER_NET_CONSUMPTION,
    DATA_DOMAIN_ENTITIES,
    DATA_GROUP_SIZES,
    DEFAULT_ENERGY_SENSOR_PRECISION,
    DEFAULT_GROUP_ENERGY_UPDATE_INTERVAL,
    DEFAULT_GROUP_POWER_UPDATE_INTERVAL,
    DEFAULT_POWER_SENSOR_PRECISION,
    DOMAIN,
    ENTRY_DATA_ENERGY_ENTITY,
    ENTRY_DATA_POWER_ENTITY,
    SERVICE_RESET_ENERGY,
    UNAVAILABLE_STATES,
    GroupType,
    SensorType,
    UnitPrefix,
)
from custom_components.powercalc.group_include.filter import (
    AreaFilter,
    CompositeFilter,
    DeviceFilter,
    EntityFilter,
    FilterOperator,
    FloorFilter,
)
from custom_components.powercalc.group_include.include import find_entities
from custom_components.powercalc.helpers import async_cache
from custom_components.powercalc.sensors.abstract import (
    BaseEntity,
    generate_energy_sensor_entity_id,
    generate_energy_sensor_name,
    generate_power_sensor_entity_id,
    generate_power_sensor_name,
)
from custom_components.powercalc.sensors.energy import EnergySensor, VirtualEnergySensor
from custom_components.powercalc.sensors.energy_related import create_energy_related_sensors
from custom_components.powercalc.sensors.power import PowerSensor
from custom_components.powercalc.unit import (
    ENERGY_UNIT_PREFIX_MAPPING,
    convert_to_decimal,
    parse_decimal,
)

ENTITY_ID_FORMAT = SENSOR_DOMAIN + ".{}"

_LOGGER = logging.getLogger(__name__)
STORAGE_KEY = "powercalc_group"
STORAGE_VERSION = 2
# How long between periodically saving the current states to disk
STATE_DUMP_INTERVAL = timedelta(minutes=10)


def create_group_sensors_yaml(
    hass: HomeAssistant,
    sensor_config: dict[str, Any],
    entities: list[Entity],
    filters: list[Callable] | None = None,
) -> list[Entity]:
    """Create grouped power and energy sensors."""
    power_sensor_ids = filter_entity_list_by_class(entities, SensorDeviceClass.POWER, filters)

    create_energy_sensor: bool = sensor_config.get(CONF_CREATE_ENERGY_SENSOR, True)
    energy_sensor_ids: set[str] = set()
    if create_energy_sensor:
        energy_sensor_ids = filter_entity_list_by_class(
            entities,
            SensorDeviceClass.ENERGY,
            filters,
        )

    group_name = str(sensor_config.get(CONF_CREATE_GROUP))
    return create_group_sensors_custom(hass, group_name, sensor_config, power_sensor_ids, energy_sensor_ids)


async def create_group_sensors_gui(
    hass: HomeAssistant,
    entry: ConfigEntry,
    sensor_config: dict,
) -> list[Entity]:
    """Create group sensors based on a config_entry."""
    group_name = str(entry.data.get(CONF_NAME))

    unique_id = sensor_config.get(CONF_UNIQUE_ID)
    if not unique_id:
        sensor_config[CONF_UNIQUE_ID] = entry.entry_id  # pragma: nocover

    power_sensor_ids = await resolve_entity_ids_recursively(hass, entry, SensorDeviceClass.POWER)

    energy_sensor_ids = await resolve_entity_ids_recursively(hass, entry, SensorDeviceClass.ENERGY)

    return create_group_sensors_custom(hass, group_name, sensor_config, power_sensor_ids, energy_sensor_ids)


def create_group_sensors_custom(
    hass: HomeAssistant,
    group_name: str,
    sensor_config: dict[str, Any],
    power_sensor_ids: set[str],
    energy_sensor_ids: set[str],
    force_create: bool = False,
) -> list[Entity]:
    """Create grouped power and energy sensors."""

    group_sensors: list[Entity] = []
    if CONF_NAME not in sensor_config:
        sensor_config[CONF_NAME] = group_name

    group_type: GroupType = GroupType(sensor_config.get(CONF_GROUP_TYPE, GroupType.CUSTOM))

    power_sensor = None
    if power_sensor_ids or force_create:
        power_sensor = create_grouped_power_sensor(
            hass,
            group_name,
            group_type,
            sensor_config,
            power_sensor_ids,
        )
        group_sensors.append(power_sensor)

    create_energy_sensor: bool = sensor_config.get(CONF_CREATE_ENERGY_SENSOR, True)
    if create_energy_sensor:
        energy_sensor = create_grouped_energy_sensor(
            hass,
            group_name,
            group_type,
            sensor_config,
            energy_sensor_ids,
            power_sensor,
        )

        group_sensors.append(energy_sensor)

        sensor_config[CONF_UTILITY_METER_NET_CONSUMPTION] = True
        group_sensors.extend(create_energy_related_sensors(hass, sensor_config, energy_sensor))

    collect_analytics(hass, None).add(DATA_GROUP_SIZES, len(power_sensor_ids) + len(energy_sensor_ids))

    return group_sensors


def filter_entity_list_by_class(
    all_entities: list,
    device_class: SensorDeviceClass,
    default_filters: list[Callable] | None = None,
) -> set[str]:
    """Filter entity list to only include entities of the given class."""
    class_name = PowerSensor if device_class == SensorDeviceClass.POWER else EnergySensor
    filter_list = default_filters.copy() if default_filters else []
    filter_list.append(lambda elm: not isinstance(elm, GroupedSensor))
    filter_list.append(lambda elm: isinstance(elm, class_name))
    return {
        x.entity_id
        for x in filter(
            lambda x: all(f(x) for f in filter_list),
            all_entities,
        )
    }


@async_cache
async def build_entity_include_filter(
    hass: HomeAssistant,
    entry: ConfigEntry,
) -> EntityFilter:
    """Build and cache the entity filter based on the entry data."""
    filters: list[EntityFilter] = []
    if CONF_AREA in entry.data:
        filters.append(AreaFilter(hass, entry.data[CONF_AREA]))
    if CONF_FLOOR in entry.data:
        filters.append(FloorFilter(hass, entry.data[CONF_FLOOR]))
    if CONF_GROUP_MEMBER_DEVICES in entry.data:
        filters.append(DeviceFilter(set(entry.data[CONF_GROUP_MEMBER_DEVICES])))
    return CompositeFilter(filters, FilterOperator.OR)


async def resolve_entity_ids_recursively(
    hass: HomeAssistant,
    entry: ConfigEntry,
    device_class: SensorDeviceClass,
    resolved_ids: set[str] | None = None,
) -> set[str]:
    """Get all the entity IDs for the current group and all the subgroups."""
    if resolved_ids is None:
        resolved_ids = set()

    _add_member_entry_ids(hass, entry, device_class, resolved_ids)
    _add_specified_sensors(entry, device_class, resolved_ids)
    await _add_include_based_sensors(hass, entry, device_class, resolved_ids)
    await _add_subgroup_entities(hass, entry, device_class, resolved_ids)

    return resolved_ids


def _add_member_entry_ids(
    hass: HomeAssistant,
    entry: ConfigEntry,
    device_class: SensorDeviceClass,
    resolved_ids: set[str],
) -> None:
    """Add power/energy sensors from the group member entries."""
    member_entry_ids = entry.data.get(CONF_GROUP_MEMBER_SENSORS) or []
    for member_entry_id in member_entry_ids:
        member_entry = hass.config_entries.async_get_entry(member_entry_id)
        if member_entry is None:
            continue

        key = _resolve_key_based_on_device_class(member_entry, device_class)
        if key and key in member_entry.data:
            resolved_ids.add(str(member_entry.data.get(key)))


def _resolve_key_based_on_device_class(member_entry: ConfigEntry, device_class: SensorDeviceClass) -> str | None:
    """Resolve the correct key for power/energy sensor based on device class."""
    if member_entry.data.get(CONF_SENSOR_TYPE) == SensorType.REAL_POWER:
        return CONF_ENTITY_ID if device_class == SensorDeviceClass.POWER else ENTRY_DATA_ENERGY_ENTITY
    return ENTRY_DATA_POWER_ENTITY if device_class == SensorDeviceClass.POWER else ENTRY_DATA_ENERGY_ENTITY


def _add_specified_sensors(entry: ConfigEntry, device_class: SensorDeviceClass, resolved_ids: set[str]) -> None:
    """Add additional power/energy sensors specified by the user."""
    conf_key = CONF_GROUP_POWER_ENTITIES if device_class == SensorDeviceClass.POWER else CONF_GROUP_ENERGY_ENTITIES
    resolved_ids.update(entry.data.get(conf_key) or [])


async def _add_include_based_sensors(
    hass: HomeAssistant,
    entry: ConfigEntry,
    device_class: SensorDeviceClass,
    resolved_ids: set[str],
) -> None:
    """Add entities from the defined areas, devices and floors."""
    if all(k not in entry.data for k in (CONF_AREA, CONF_FLOOR, CONF_GROUP_MEMBER_DEVICES)):
        return

    result = await find_entities(
        hass,
        await build_entity_include_filter(hass, entry),
        bool(entry.data.get(CONF_INCLUDE_NON_POWERCALC_SENSORS)),
    )
    resolved_ids.update(filter_entity_list_by_class(result.resolved, device_class))


async def _add_subgroup_entities(
    hass: HomeAssistant,
    entry: ConfigEntry,
    device_class: SensorDeviceClass,
    resolved_ids: set[str],
) -> None:
    """Recursively add entities from subgroups."""
    subgroups = entry.data.get(CONF_SUB_GROUPS)
    if not subgroups:
        return

    for subgroup_entry_id in subgroups:
        subgroup_entry = hass.config_entries.async_get_entry(subgroup_entry_id)
        if subgroup_entry is None:
            _LOGGER.error("Subgroup config entry not found: %s", subgroup_entry_id)
            continue

        await resolve_entity_ids_recursively(hass, subgroup_entry, device_class, resolved_ids)


@callback
def create_grouped_power_sensor(
    hass: HomeAssistant,
    group_name: str,
    group_type: GroupType,
    sensor_config: dict,
    power_sensor_ids: set[str],
) -> GroupedPowerSensor:
    name = generate_power_sensor_name(sensor_config, group_name)
    unique_id = sensor_config.get(CONF_UNIQUE_ID)
    if not unique_id:
        unique_id = generate_unique_id(sensor_config)
    entity_id = generate_power_sensor_entity_id(
        hass,
        sensor_config,
        name=group_name,
        unique_id=unique_id,
    )

    _LOGGER.debug("Creating grouped power sensor: %s (entity_id=%s, unique_id=%s)", name, entity_id, unique_id)

    return GroupedPowerSensor(
        hass=hass,
        name=name,
        entities=power_sensor_ids,
        unique_id=unique_id,
        sensor_config=sensor_config,
        group_type=group_type,
        entity_id=entity_id,
    )


@callback
def create_grouped_energy_sensor(
    hass: HomeAssistant,
    group_name: str,
    group_type: GroupType,
    sensor_config: dict,
    energy_sensor_ids: set[str],
    power_sensor: GroupedPowerSensor | None,
) -> EnergySensor:
    name = generate_energy_sensor_name(sensor_config, group_name)
    unique_id = sensor_config.get(CONF_UNIQUE_ID)
    energy_unique_id = None
    if unique_id:
        energy_unique_id = f"{unique_id}_energy"
    entity_id = generate_energy_sensor_entity_id(
        hass,
        sensor_config,
        name=group_name,
        unique_id=energy_unique_id,
    )

    _LOGGER.debug("Creating grouped energy sensor: %s (entity_id=%s)", name, entity_id)

    should_create_riemann = bool(sensor_config.get(CONF_FORCE_CALCULATE_GROUP_ENERGY, False))
    if not should_create_riemann and not energy_sensor_ids:
        should_create_riemann = True
    if group_type == GroupType.DOMAIN and sensor_config.get(CONF_DOMAIN) == "all":
        should_create_riemann = False
    if power_sensor and should_create_riemann:
        return VirtualEnergySensor(
            hass=hass,
            source_entity=power_sensor.entity_id,
            entity_id=entity_id,
            name=name,
            unique_id=energy_unique_id,
            sensor_config=sensor_config,
            unit_prefix=sensor_config.get(CONF_ENERGY_SENSOR_UNIT_PREFIX, UnitPrefix.NONE),
        )

    return GroupedEnergySensor(
        hass=hass,
        name=name,
        entities=energy_sensor_ids,
        unique_id=energy_unique_id,
        sensor_config=sensor_config,
        group_type=group_type,
        entity_id=entity_id,
    )


def generate_unique_id(sensor_config: dict[str, Any]) -> str:
    return str(sensor_config[CONF_NAME])


class GroupedSensor(BaseEntity, SensorEntity):
    """Base class for grouped sensors."""

    _attr_should_poll = False
    _unrecorded_attributes = frozenset({ATTR_ENTITIES, ATTR_IS_GROUP})
    _is_energy_sensor = False
    _attr_force_update = True

    def __init__(
        self,
        hass: HomeAssistant,
        name: str,
        entities: set[str],
        entity_id: str,
        sensor_config: dict[str, Any],
        group_type: GroupType,
        unique_id: str | None = None,
    ) -> None:
        self.entity_id = entity_id

        self._attr_name = name
        # Remove own entity from entities, when it happens to be there. To prevent recursion
        entities.discard(entity_id)
        self._entities = entities
        self._sensor_config = sensor_config
        if self._is_energy_sensor:
            self._rounding_digits = int(
                sensor_config.get(CONF_ENERGY_SENSOR_PRECISION, DEFAULT_ENERGY_SENSOR_PRECISION),
            )
            self._update_interval: int = int(
                sensor_config.get(CONF_GROUP_ENERGY_UPDATE_INTERVAL, DEFAULT_GROUP_ENERGY_UPDATE_INTERVAL),
            )
        else:
            self._rounding_digits = int(sensor_config.get(CONF_POWER_SENSOR_PRECISION, DEFAULT_POWER_SENSOR_PRECISION))
            self._update_interval = int(
                sensor_config.get(CONF_GROUP_POWER_UPDATE_INTERVAL, DEFAULT_GROUP_POWER_UPDATE_INTERVAL),
            )
        self._attr_suggested_display_precision = self._rounding_digits
        if unique_id:
            self._attr_unique_id = unique_id
        self._native_value_exact = Decimal(0)
        self._member_states: dict[str, Decimal] = {}
        self._ignore_unavailable_state = bool(self._sensor_config.get(CONF_IGNORE_UNAVAILABLE_STATE))
        self._group_type = group_type
        self._start_time: float = time.time()
        self._last_update_time: float = 0
        self._update_interval_exceeded_callback: CALLBACK_TYPE | None = None

    async def async_added_to_hass(self) -> None:
        """Register state listeners."""
        await super().async_added_to_hass()

        if self._update_interval > 0:
            self.async_on_remove(self._cancel_update_interval_exceeded_callback)

        self.async_on_remove(start.async_at_start(self.hass, self.on_start))

        if CONF_HIDE_MEMBERS in self._sensor_config:
            self._async_hide_members(bool(self._sensor_config.get(CONF_HIDE_MEMBERS)))

        if not self._sensor_config.get(CONF_DISABLE_EXTENDED_ATTRIBUTES, False):
            self._attr_extra_state_attributes = {
                ATTR_ENTITIES: self._entities,
                ATTR_IS_GROUP: True,
            }

    async def async_will_remove_from_hass(self) -> None:
        """
        This will trigger when entity is about to be removed from HA
        Unhide the entities, when they where hidden before.
        """
        if self._sensor_config.get(CONF_HIDE_MEMBERS) is True:
            self._async_hide_members(False)

    @callback
    def _async_hide_members(self, hide: bool) -> None:
        """Hide/unhide group members."""
        registry = er.async_get(self.hass)
        for entity_id in self._entities:
            registry_entry = registry.async_get(entity_id)
            if not registry_entry:
                continue

            # We don't want to touch devices which are forced hidden by the user
            if registry_entry.hidden_by == er.RegistryEntryHider.USER:
                continue

            hidden_by = er.RegistryEntryHider.INTEGRATION if hide else None
            registry.async_update_entity(entity_id, hidden_by=hidden_by)

    @callback
    def on_state_change(self, event: Event[EventStateChangedData]) -> None:
        """Triggered when one of the group entities changes state."""
        new_state = event.data.get("new_state")
        if not new_state:  # pragma: no cover
            return
        _LOGGER.debug("Group sensor %s. State change for %s: %s", self.entity_id, new_state.entity_id, new_state)
        calculated_new_state = self.calculate_new_state(new_state)
        self.set_new_state(calculated_new_state)

    async def init_domain_group(self) -> None:
        if self._group_type != GroupType.DOMAIN:
            return
        domain = self._sensor_config.get(CONF_DOMAIN)
        if domain == CONF_ALL:
            entity_registry = er.async_get(self.hass)
            entities = {
                entity.entity_id
                for entity in entity_registry.entities.values()
                if entity.device_class == self.device_class
            }
        else:
            entities = self.hass.data[DOMAIN].get(DATA_DOMAIN_ENTITIES).get(domain, [])
            entities = filter_entity_list_by_class(
                entities,
                SensorDeviceClass.ENERGY if self._is_energy_sensor else SensorDeviceClass.POWER,
            )
        excluded_entities = self._sensor_config.get(CONF_EXCLUDE_ENTITIES) or []
        self._entities = {entity for entity in entities if entity not in excluded_entities}

    async def on_start(self, _: HomeAssistant) -> None:
        """Initialize group sensor when HA is starting."""
        await self.init_domain_group()

        if not self._entities:
            _LOGGER.warning("No entities for group sensor %s, setting to unavailable", self.entity_id)
            self._attr_available = False
            self.async_write_ha_state()
            return

        self.async_on_remove(
            async_track_state_change_event(
                self.hass,
                self._entities,
                self.on_state_change,
            ),
        )

        await self.initial_update()

    async def initial_update(self) -> None:
        """Initial update for the group sensor state."""
        all_states = [self.hass.states.get(entity_id) for entity_id in self._entities]
        states: list[State] = list(filter(None, all_states))
        available_states = [state for state in states if state and state.state not in UNAVAILABLE_STATES]
        if not available_states and not self._ignore_unavailable_state:
            new_state: Decimal | str = STATE_UNAVAILABLE
        else:
            new_state = self.calculate_initial_state(available_states, states)
        self.set_new_state(new_state)

    @callback
    def set_new_state(self, state: Decimal | str) -> None:
        """Set the new state and update the entity."""
        if state == STATE_UNAVAILABLE or not isinstance(state, Decimal):
            self._attr_available = self._ignore_unavailable_state
            self.async_write_ha_state()
            return

        self._attr_available = True
        self._set_native_value(state, write_state=False)

        # Throttled future update pending, return early
        if self._update_interval_exceeded_callback:
            return

        current_time = time.time()
        if self._should_throttle(current_time):

            @callback
            def _update_interval_callback(now: datetime) -> None:
                self._update_interval_exceeded_callback = None
                self._last_update_time = time.time()
                self.async_write_ha_state()

            self._update_interval_exceeded_callback = async_call_later(
                self.hass,
                self._update_interval,
                _update_interval_callback,
            )
            return

        self._cancel_update_interval_exceeded_callback()
        self._last_update_time = current_time
        self.async_write_ha_state()

    def _should_throttle(self, current_time: float) -> bool:
        if self._update_interval == 0:
            return False

        # Don't throttle initial updates within first 5 seconds after startup
        if current_time - self._start_time < 5:
            return False

        if self._last_update_time == 0:
            return False  # pragma: no cover

        # Apply a minimum throttle of 100ms to prevent flooding during rapid changes
        if current_time - self._last_update_time < 0.1:
            return True

        return current_time - self._last_update_time < self._update_interval

    def _cancel_update_interval_exceeded_callback(self) -> None:
        if self._update_interval_exceeded_callback:  # pragma: no cover
            self._update_interval_exceeded_callback()
            self._update_interval_exceeded_callback = None

    def _get_state_value_in_native_unit(self, state: State) -> Decimal:
        """Convert value of member entity state to match the unit of measurement of the group sensor."""
        unit = state.attributes.get(ATTR_UNIT_OF_MEASUREMENT)
        if unit and self._attr_native_unit_of_measurement != unit:
            value = convert_to_decimal(state.state, unit, self._attr_native_unit_of_measurement)
        else:
            value = parse_decimal(state.state)
        if value is None:
            _LOGGER.warning(
                "Error converting state value %s to Decimal for %s",
                state.state,
                state.entity_id,
            )
            return Decimal(0)
        return value

    def _set_native_value(self, value: Decimal, write_state: bool = True) -> None:
        self._native_value_exact = value
        self._attr_native_value = round(value, self._rounding_digits)
        if write_state:
            self.async_write_ha_state()

    @property
    def entities(self) -> set[str]:
        return self._entities

    def get_group_entities(self) -> dict[str, set[str]]:
        return {ATTR_ENTITIES: self._entities}

    def debug_group(self) -> dict[str, Any]:
        members: dict[str, dict[str, str | None]] = {}
        for entity_id in sorted(self._entities):
            members[entity_id] = self._get_member_debug_info(entity_id)

        return {
            ATTR_STATE: str(self.state),
            ATTR_UNIT_OF_MEASUREMENT: self.native_unit_of_measurement,
            ATTR_MEMBERS: members,
        }

    def _get_member_debug_info(self, entity_id: str) -> dict[str, str | None]:
        state = self.hass.states.get(entity_id)
        if state is None:
            return {
                ATTR_STATE: None,
                ATTR_UNIT_OF_MEASUREMENT: None,
            }

        if state.state in UNAVAILABLE_STATES:
            return {
                ATTR_STATE: str(state.state),
                ATTR_UNIT_OF_MEASUREMENT: state.attributes.get(ATTR_UNIT_OF_MEASUREMENT),
            }

        converted_value = round(self._get_state_value_in_native_unit(state), self._rounding_digits)
        return {
            ATTR_STATE: str(converted_value),
            ATTR_UNIT_OF_MEASUREMENT: self.native_unit_of_measurement,
        }

    @abstractmethod
    def calculate_initial_state(
        self,
        member_available_states: list[State],
        member_states: list[State],
    ) -> Decimal | str:
        """Implementation for the initial state calculation"""

    @abstractmethod
    def calculate_new_state(
        self,
        state: State,
    ) -> Decimal | str:
        """Implementation for the state calculation whenever a member entity changes state"""


class GroupedPowerSensor(GroupedSensor, PowerSensor):
    """Grouped power sensor. Sums all values of underlying individual power sensors."""

    _attr_device_class = SensorDeviceClass.POWER
    _attr_state_class = SensorStateClass.MEASUREMENT
    _attr_native_unit_of_measurement = UnitOfPower.WATT
    _is_energy_sensor = False

    def calculate_initial_state(
        self,
        member_available_states: list[State],
        member_states: list[State],
    ) -> Decimal | str:
        self._member_states = {
            state.entity_id: self._get_state_value_in_native_unit(state) for state in member_available_states
        }
        return self.get_summed_state()

    def calculate_new_state(self, state: State) -> Decimal | str:
        if state.state in UNAVAILABLE_STATES:
            if state.entity_id in self._member_states:
                del self._member_states[state.entity_id]
        else:
            self._member_states[state.entity_id] = self._get_state_value_in_native_unit(state)
        return self.get_summed_state()

    def get_summed_state(self) -> Decimal | str:
        if not self._member_states:
            return Decimal(0) if self._ignore_unavailable_state else STATE_UNAVAILABLE

        return Decimal(sum(self._member_states.values()))


class GroupedEnergySensor(GroupedSensor, RestoreSensor, EnergySensor):
    """Grouped energy sensor. Sums all values of underlying individual energy sensors."""

    _attr_device_class = SensorDeviceClass.ENERGY
    _attr_state_class = SensorStateClass.TOTAL
    _is_energy_sensor = True

    def __init__(
        self,
        hass: HomeAssistant,
        name: str,
        entities: set[str],
        entity_id: str,
        sensor_config: dict[str, Any],
        group_type: GroupType,
        unique_id: str | None = None,
    ) -> None:
        super().__init__(
            hass,
            name,
            entities,
            entity_id,
            sensor_config,
            group_type,
            unique_id,
        )

        self._attr_native_unit_of_measurement = ENERGY_UNIT_PREFIX_MAPPING.get(
            sensor_config.get(CONF_ENERGY_SENSOR_UNIT_PREFIX, UnitPrefix.NONE),
            UnitOfEnergy.WATT_HOUR,
        )
        self._prev_state_store: PreviousStateStore = PreviousStateStore(hass)

    async def async_added_to_hass(self) -> None:
        """Register state listeners."""

        self._prev_state_store = await PreviousStateStore.async_get_instance(self.hass)
        # Clean up any entities that are no longer part of the group
        self._prev_state_store.cleanup_entity_states(self.entity_id, self._entities)

        await self.restore_last_state()

        await super().async_added_to_hass()

    async def async_reset(self) -> None:
        """Reset the group sensor and underlying member sensor when supported."""
        _LOGGER.debug("%s: Reset grouped energy sensor", self.entity_id)
        self._set_native_value(Decimal(0))

        for entity_id in self._entities:
            _LOGGER.debug("Resetting %s", entity_id)
            await self.hass.services.async_call(
                DOMAIN,
                SERVICE_RESET_ENERGY,
                {ATTR_ENTITY_ID: entity_id},
                blocking=True,
            )
            if self._prev_state_store:
                self._prev_state_store.set_entity_state(
                    self.entity_id,
                    entity_id,
                    State(entity_id, "0.00"),
                )

    async def async_calibrate(self, value: str) -> None:
        _LOGGER.debug("%s: Calibrate group energy sensor to: %s", self.entity_id, value)
        self._set_native_value(Decimal(value))

    def calculate_initial_state(
        self,
        member_available_states: list[State],
        member_states: list[State],
    ) -> Decimal:
        """Calculate the new group energy sensor state.

        For each member, calculate the delta between the previous known state and the current.
        """
        group_sum = self._native_value_exact
        _LOGGER.debug("%s: Recalculate, current value: %s", self.entity_id, group_sum)
        for state in member_available_states:
            group_sum += self.calculate_delta(state)

        _LOGGER.debug(
            "%s: New value: %s",
            self.entity_id,
            round(group_sum, self._rounding_digits),
        )
        return group_sum

    def calculate_new_state(self, state: State) -> Decimal | str:
        group_sum = self._native_value_exact
        if state.state in UNAVAILABLE_STATES:
            if group_sum == 0:
                return STATE_UNAVAILABLE
            _LOGGER.debug(
                "skipping state for %s, sensor unavailable or unknown",
                state.entity_id,
            )
            return group_sum

        _LOGGER.debug("%s: Recalculate, current value: %s", self.entity_id, group_sum)

        group_sum += self.calculate_delta(state)
        _LOGGER.debug(
            "%s: New value: %s",
            self.entity_id,
            round(group_sum, self._rounding_digits),
        )
        return group_sum

    def calculate_delta(self, state: State) -> Decimal:
        """Calculate the delta between the current and previous state."""
        prev_state = self._prev_state_store.get_entity_state(
            self.entity_id,
            state.entity_id,
        )

        cur_value = self._get_state_value_in_native_unit(state)
        prev_value = self._get_state_value_in_native_unit(prev_state) if prev_state is not None else Decimal(0)

        # Always store current state as the new "previous" state
        self._prev_state_store.set_entity_state(
            self.entity_id,
            state.entity_id,
            state,
        )

        start_at_zero = self._sensor_config.get(CONF_GROUP_ENERGY_START_AT_ZERO, True)
        delta = Decimal(0) if prev_state is None and start_at_zero else cur_value - prev_value

        if _LOGGER.isEnabledFor(logging.DEBUG):  # pragma: no cover
            _LOGGER.debug(
                "delta for entity %s: %s, prev=%s, cur=%s",
                state.entity_id,
                round(delta, self._rounding_digits),
                round(prev_value, self._rounding_digits),
                round(cur_value, self._rounding_digits),
            )

        if delta < 0:
            _LOGGER.warning(
                "skipping state for %s, probably erroneous value or sensor was reset",
                state.entity_id,
            )
            return Decimal(0)

        return delta

    async def restore_last_state(self) -> None:
        """Restore the last known state of the group sensor."""
        last_state = await self.async_get_last_state()
        if last_state and last_state.state in [None, STATE_UNKNOWN, STATE_UNAVAILABLE]:
            return

        last_sensor_state = await self.async_get_last_sensor_data()
        if last_sensor_state and last_sensor_state.native_value:
            restored = parse_decimal(last_sensor_state.native_value)
        elif last_state:
            restored = parse_decimal(last_state.state)
        else:
            restored = None

        if restored is None:
            _LOGGER.warning("%s: Could not restore last state", self.entity_id)
            return

        self._set_native_value(restored)
        _LOGGER.debug(
            "%s: Restoring state: %s",
            self.entity_id,
            self._attr_native_value,
        )


class PreviousStateStore:
    @staticmethod
    @singleton("powercalc_group_storage")
    async def async_get_instance(hass: HomeAssistant) -> PreviousStateStore:
        """Get the singleton instance of this data helper."""
        instance = PreviousStateStore(hass)
        instance.states = {}

        try:
            _LOGGER.debug("Load previous energy sensor states from store")
            stored_states = await instance.store.async_load() or {}
            for group, entities in stored_states.items():
                instance.states[group] = {
                    entity_id: State.from_dict(json_state) for (entity_id, json_state) in entities.items()
                }
        except HomeAssistantError as exc:  # pragma: no cover
            _LOGGER.error("Error loading previous energy sensor states", exc_info=exc)

        instance.async_setup_dump()

        return instance

    def __init__(self, hass: HomeAssistant) -> None:
        self.store: Store = PreviousStateStoreStore(
            hass,
            STORAGE_VERSION,
            STORAGE_KEY,
            encoder=JSONEncoder,
        )
        self.states: dict[str, dict[str, State | None]] = {}
        self.hass = hass

    def get_entity_state(self, group: str, entity_id: str) -> State | None:
        group_states = self.states.get(group)
        if group_states is None:
            return None
        return group_states.get(entity_id)

    def set_entity_state(self, group: str, entity_id: str, state: State) -> None:
        """Set the state for an energy sensor."""
        self.states.setdefault(group, {})[entity_id] = state

    def cleanup_entity_states(self, group: str, current_entities: set[str]) -> None:
        """Remove entity states that are no longer part of the group."""
        group_states = self.states.get(group)
        if group_states is None:
            return

        # Find entities that are in the store but not in the current set
        entities_to_remove = set(group_states.keys()) - current_entities

        # Remove those entities from the store
        for entity_id in entities_to_remove:
            _LOGGER.debug("Removing entity %s from group %s in PreviousStateStore", entity_id, group)
            group_states.pop(entity_id, None)

    async def persist_states(self) -> None:
        """Save the current states to storage."""
        try:
            await self.store.async_save(self.states)
        except HomeAssistantError as exc:  # pragma: no cover
            _LOGGER.error("Error saving current states", exc_info=exc)

    @callback
    def async_setup_dump(self) -> None:
        """Set up the listeners for persistence."""

        async def _async_dump_states(*_: object) -> None:
            await self.persist_states()

        # Dump states periodically
        cancel_interval = async_track_time_interval(
            self.hass,
            _async_dump_states,
            STATE_DUMP_INTERVAL,
            cancel_on_shutdown=True,
        )

        async def _async_dump_states_at_stop(*_: object) -> None:
            cancel_interval()
            await self.persist_states()

        # Dump states when stopping hass
        self.hass.bus.async_listen_once(
            EVENT_HOMEASSISTANT_STOP,
            _async_dump_states_at_stop,
        )


class PreviousStateStoreStore(Store):
    """Store area registry data."""

    async def _async_migrate_func(  # type: ignore
        self,
        old_major_version: int,
        old_minor_version: int,
        old_data: dict[str, list[dict[str, Any]]],
    ) -> dict[str, Any]:
        """Migrate to the new version."""
        if old_major_version == 1:
            return {}
        return old_data  # pragma: no cover