fix: Corrected RAIN and DAILYRAIN for PWS protocol.

The `RAININ` suppose to be accumulated rainfall in 60 minutes. So the
unit must be in `mm/h` or `in/h`.
In the opposite `DAILYRAIN` is rain in the day do far, represented in
accumulated `mm` or `in`.

custom_components/sws12500/const.py

@@ -83,6 +83,10 @@ CH8_BATTERY: Final = "ch8_battery"
 HEAT_INDEX: Final = "heat_index"
 CHILL_INDEX: Final = "chill_index"
 WBGT_TEMP: Final = "wbgt_temp"
+HCHO: Final = "hcho"
+VOC: Final = "voc"
+T9_BATTERY: Final = "t9_battery"  # T9 sensors are HCHO and VOC
+T9_CONN: Final = "t9_conn"
 
 
 # Health specific constants
@@ -380,6 +384,9 @@ REMAP_WSLINK_ITEMS: dict[str, str] = {
     "t234c6bat": CH7_BATTERY,
     "t234c7bat": CH8_BATTERY,
     "t1wbgt": WBGT_TEMP,
+    "t9hcho": HCHO,
+    "t9voclv": VOC,
+    "t9bat": T9_BATTERY,  # T9 battery is 0-5, where 5 is full
 }
 
 # NOTE: Add more sensors
@@ -481,6 +488,31 @@ BATTERY_LIST = [
     CH8_BATTERY,
 ]
 
+BATTERY_NON_BINARY: list[str] = [T9_BATTERY]
+
+CONNECTION_GATED_SENSORS: Final[dict[str, list[str]]] = {
+    "t9cn": [HCHO, VOC, T9_BATTERY],
+}
+
+
+class VOCLevel(StrEnum):
+    """WSLink VOC Level 1-5 (1-worst)."""
+
+    UNHEALTHY = "unhealthy"
+    POOR = "poor"
+    MODERATE = "moderate"
+    GOOD = "good"
+    EXCELLENT = "excellent"
+
+
+VOC_LEVEL_MAP: dict[int, VOCLevel] = {
+    1: VOCLevel.UNHEALTHY,
+    2: VOCLevel.POOR,
+    3: VOCLevel.MODERATE,
+    4: VOCLevel.GOOD,
+    5: VOCLevel.EXCELLENT,
+}
+
 
 class UnitOfDir(StrEnum):
     """Wind direrction azimut."""

custom_components/sws12500/sensors_weather.py

@@ -137,10 +137,10 @@ SENSOR_TYPES_WEATHER_API: tuple[WeatherSensorEntityDescription, ...] = (
     ),
     WeatherSensorEntityDescription(
         key=RAIN,
-        native_unit_of_measurement=UnitOfPrecipitationDepth.INCHES,
-        device_class=SensorDeviceClass.PRECIPITATION,
-        state_class=SensorStateClass.TOTAL,
-        suggested_unit_of_measurement=UnitOfPrecipitationDepth.MILLIMETERS,
+        native_unit_of_measurement=UnitOfVolumetricFlux.INCHES_PER_HOUR,
+        device_class=SensorDeviceClass.PRECIPITATION_INTENSITY,
+        state_class=SensorStateClass.MEASUREMENT,
+        suggested_unit_of_measurement=UnitOfVolumetricFlux.MILLIMETERS_PER_HOUR,
         suggested_display_precision=2,
         icon="mdi:weather-pouring",
         translation_key=RAIN,
@@ -148,10 +148,10 @@ SENSOR_TYPES_WEATHER_API: tuple[WeatherSensorEntityDescription, ...] = (
     ),
     WeatherSensorEntityDescription(
         key=DAILY_RAIN,
-        native_unit_of_measurement=UnitOfVolumetricFlux.INCHES_PER_DAY,
+        native_unit_of_measurement=UnitOfPrecipitationDepth.INCHES,
         state_class=SensorStateClass.MEASUREMENT,
-        device_class=SensorDeviceClass.PRECIPITATION_INTENSITY,
-        suggested_unit_of_measurement=UnitOfVolumetricFlux.MILLIMETERS_PER_DAY,
+        device_class=SensorDeviceClass.PRECIPITATION,
+        suggested_unit_of_measurement=UnitOfPrecipitationDepth.MILLIMETERS,
         suggested_display_precision=2,
         icon="mdi:weather-pouring",
         translation_key=DAILY_RAIN,

custom_components/sws12500/sensors_wslink.py

@@ -2,6 +2,7 @@
 
 from homeassistant.components.sensor import SensorDeviceClass, SensorStateClass
 from homeassistant.const import (
+    CONCENTRATION_PARTS_PER_BILLION,
     DEGREE,
     PERCENTAGE,
     UV_INDEX,
@@ -39,6 +40,7 @@ from .const import (
     CHILL_INDEX,
     DAILY_RAIN,
     DEW_POINT,
+    HCHO,
     HEAT_INDEX,
     HOURLY_RAIN,
     INDOOR_BATTERY,
@@ -50,7 +52,9 @@ from .const import (
     OUTSIDE_TEMP,
     RAIN,
     SOLAR_RADIATION,
+    T9_BATTERY,
     UV,
+    VOC,
     WBGT_TEMP,
     WEEKLY_RAIN,
     WIND_AZIMUT,
@@ -60,6 +64,7 @@ from .const import (
     YEARLY_RAIN,
     UnitOfBat,
     UnitOfDir,
+    VOCLevel,
 )
 from .sensors_common import WeatherSensorEntityDescription
 from .utils import battery_level, to_float, to_int, wind_dir_to_text
@@ -518,4 +523,30 @@ SENSOR_TYPES_WSLINK: tuple[WeatherSensorEntityDescription, ...] = (
         suggested_display_precision=2,
         value_fn=to_float,
     ),
+    WeatherSensorEntityDescription(
+        key=HCHO,
+        translation_key=HCHO,
+        device_class=SensorDeviceClass.VOLATILE_ORGANIC_COMPOUNDS_PARTS,
+        native_unit_of_measurement=CONCENTRATION_PARTS_PER_BILLION,
+        state_class=SensorStateClass.MEASUREMENT,
+        icon="mdi:molecule",
+        value_fn=lambda data: cast("int", data),
+    ),
+    WeatherSensorEntityDescription(
+        key=VOC,
+        translation_key=VOC,
+        device_class=SensorDeviceClass.ENUM,
+        options=list(VOCLevel),
+        icon="mdi:air-filter",
+        value_fn=lambda data: cast("str", voc_level_to_text(data)),
+    ),
+    WeatherSensorEntityDescription(
+        key=T9_BATTERY,
+        translation_key=T9_BATTERY,
+        device_class=SensorDeviceClass.BATTERY,
+        native_unit_of_measurement=PERCENTAGE,
+        state_class=SensorStateClass.MEASUREMENT,
+        suggested_display_precision=0,
+        value_fn=battery_5step_to_pct,
+    ),
 )

custom_components/sws12500/translations/cs.json

@@ -308,6 +308,22 @@
       "wbgt_temp": {
         "name": "WBGT index"
       },
+      "hcho": {
+        "name": "Formaldehyd (HCHO)"
+      },
+      "voc": {
+        "name": "Úroveň VOC",
+        "state": {
+          "unhealthy": "Nezdravá",
+          "poor": "Špatná",
+          "moderate": "Průměrná",
+          "good": "Dobrá",
+          "excellent": "Velmi dobrá"
+        }
+      },
+      "t9_battery": {
+        "name": "Baterie senzoru HCHO/VOC"
+      },
       "wind_azimut": {
         "name": "Azimut",
         "state": {

custom_components/sws12500/translations/en.json

@@ -315,6 +315,22 @@
       "wbgt_index": {
         "name": "WBGT index"
       },
+      "hcho": {
+        "name": "Formaldehyde (HCHO)"
+      },
+      "voc": {
+        "name": "VOC level",
+        "state": {
+          "unhealthy": "Unhealthy",
+          "poor": "Poor",
+          "moderate": "Moderate",
+          "good": "Good",
+          "excellent": "Excellent"
+        }
+      },
+      "t9_battery": {
+        "name": "HCHO/VOC sensor battery"
+      },
       "wind_azimut": {
         "name": "Bearing",
         "state": {

custom_components/sws12500/utils.py

@@ -24,15 +24,19 @@ from homeassistant.helpers.translation import async_get_translations
 
 from .const import (
     AZIMUT,
+    CONNECTION_GATED_SENSORS,
+    DATABASE_PATH,
     DEV_DBG,
     OUTSIDE_HUMIDITY,
     OUTSIDE_TEMP,
     REMAP_ITEMS,
     REMAP_WSLINK_ITEMS,
     SENSORS_TO_LOAD,
+    VOC_LEVEL_MAP,
     WIND_SPEED,
     UnitOfBat,
     UnitOfDir,
+    VOCLevel,
 )
 
 _LOGGER = logging.getLogger(__name__)
@@ -52,9 +56,7 @@ async def translations(
 
     language: str = hass.config.language
 
-    _translations = await async_get_translations(
-        hass, language, category, [translation_domain]
-    )
+    _translations = await async_get_translations(hass, language, category, [translation_domain])
     if localize_key in _translations:
         return _translations[localize_key]
     return None
@@ -74,15 +76,11 @@ async def translated_notification(
 
     localize_key = f"component.{translation_domain}.{category}.{translation_key}.{key}"
 
-    localize_title = (
-        f"component.{translation_domain}.{category}.{translation_key}.title"
-    )
+    localize_title = f"component.{translation_domain}.{category}.{translation_key}.title"
 
     language: str = cast("str", hass.config.language)
 
-    _translations = await async_get_translations(
-        hass, language, category, [translation_domain]
-    )
+    _translations = await async_get_translations(hass, language, category, [translation_domain])
     if localize_key in _translations:
         if not translation_placeholders:
             persistent_notification.async_create(
@@ -93,17 +91,10 @@ async def translated_notification(
             )
         else:
             message = _translations[localize_key].format(**translation_placeholders)
-            persistent_notification.async_create(
-                hass, message, _translations[localize_title], notification_id
-            )
+            persistent_notification.async_create(hass, message, _translations[localize_title], notification_id)
 
 
-async def update_options(
-    hass: HomeAssistant,
-    entry: ConfigEntry,
-    update_key: str,
-    update_value: str | list[str] | bool,
-) -> bool:
+async def update_options(hass: HomeAssistant, entry: ConfigEntry, update_key, update_value) -> bool:
     """Update config.options entry."""
     conf = {**entry.options}
     conf[update_key] = update_value
@@ -380,11 +371,7 @@ def chill_index(
 
     return (
         round(
-            (
-                (35.7 + (0.6215 * temp))
-                - (35.75 * (wind**0.16))
-                + (0.4275 * (temp * (wind**0.16)))
-            ),
+            ((35.7 + (0.6215 * temp)) - (35.75 * (wind**0.16)) + (0.4275 * (temp * (wind**0.16)))),
             2,
         )
         if temp < 50 and wind > 3

tests/test_t9_air_quality.py

@@ -0,0 +1,231 @@
+"""Tests for the T9 air-quality (HCHO / VOC) sensor support.
+
+Covers what was added for the WSLink ``t9hcho`` / ``t9voclv`` / ``t9bat`` /
+``t9cn`` parameters:
+
+- the new constants (``REMAP_WSLINK_ITEMS``, ``CONNECTION_GATED_SENSORS``,
+  ``BATTERY_NON_BINARY``, ``VOCLevel`` / ``VOC_LEVEL_MAP``)
+- the ``utils.voc_level_to_text`` and ``utils.battery_5step_to_pct`` helpers
+- the connection gating in ``utils.remap_wslink_items``
+- the new ``SENSOR_TYPES_WSLINK`` entity descriptions
+- the ``hcho`` / ``voc`` / ``t9_battery`` entries in the translation files
+"""
+
+from __future__ import annotations
+
+import json
+from pathlib import Path
+
+import pytest
+
+from custom_components.sws12500.const import (
+    BATTERY_LIST,
+    BATTERY_NON_BINARY,
+    CONNECTION_GATED_SENSORS,
+    HCHO,
+    OUTSIDE_TEMP,
+    REMAP_WSLINK_ITEMS,
+    T9_BATTERY,
+    VOC,
+    VOC_LEVEL_MAP,
+    VOCLevel,
+)
+from custom_components.sws12500.sensors_wslink import SENSOR_TYPES_WSLINK
+from custom_components.sws12500.utils import battery_5step_to_pct, remap_wslink_items, voc_level_to_text
+from homeassistant.components.sensor import SensorDeviceClass, SensorStateClass
+from homeassistant.const import CONCENTRATION_PARTS_PER_BILLION, PERCENTAGE
+
+# Realistic WSLink payload taken from an issue report: the station sends every
+# parameter, even for channels with no sensor connected (``*cn == "0"``).
+ISSUE_PAYLOAD = {
+    "rbar": "1013.3",
+    "intem": "25.0",
+    "inhum": "44",
+    "t1cn": "1",
+    "t1tem": "11.3",
+    "t1hum": "92",
+    "t234c1cn": "1",
+    "t234c2cn": "1",
+    "t234c3cn": "0",
+    "t8cn": "0",
+    "t9cn": "1",
+    "t9hcho": "57",
+    "t9voclv": "5",
+    "t9bat": "5",
+    "t10cn": "0",
+    "t11cn": "0",
+    "apiver": "1.00",
+}
+
+
+# --- constants -------------------------------------------------------------
+
+
+def test_t9_keys_are_remapped() -> None:
+    assert REMAP_WSLINK_ITEMS["t9hcho"] == HCHO
+    assert REMAP_WSLINK_ITEMS["t9voclv"] == VOC
+    assert REMAP_WSLINK_ITEMS["t9bat"] == T9_BATTERY
+    # t9cn is intentionally NOT remapped - it is only used as a gating flag.
+    assert "t9cn" not in REMAP_WSLINK_ITEMS
+
+
+def test_connection_gated_sensors_definition() -> None:
+    assert CONNECTION_GATED_SENSORS == {"t9cn": [HCHO, VOC, T9_BATTERY]}
+
+
+def test_t9_battery_is_non_binary_only() -> None:
+    assert BATTERY_NON_BINARY == [T9_BATTERY]
+    # the 0-5 / percentage battery must not be treated as a binary low/normal one
+    assert T9_BATTERY not in BATTERY_LIST
+
+
+def test_voc_level_map_is_complete_and_ordered() -> None:
+    # 1 == highest VOC reading (worst air) ... 5 == lowest VOC reading (best air)
+    assert set(VOC_LEVEL_MAP) == {1, 2, 3, 4, 5}
+    assert set(VOC_LEVEL_MAP.values()) == set(VOCLevel)
+    assert VOC_LEVEL_MAP[1] is VOCLevel.UNHEALTHY
+    assert VOC_LEVEL_MAP[5] is VOCLevel.EXCELENT
+    assert [member.value for member in VOCLevel] == [
+        "unhealthy",
+        "poor",
+        "moderate",
+        "good",
+        "excellent",
+    ]
+
+
+# --- voc_level_to_text -----------------------------------------------------
+
+
+@pytest.mark.parametrize("empty", [None, ""])
+def test_voc_level_to_text_handles_empty(empty) -> None:
+    assert voc_level_to_text(empty) is None
+
+
+@pytest.mark.parametrize(
+    ("raw", "expected"),
+    [
+        ("1", VOCLevel.UNHEALTHY),
+        ("2", VOCLevel.POOR),
+        ("3", VOCLevel.MODERATE),
+        ("4", VOCLevel.GOOD),
+        ("5", VOCLevel.EXCELENT),
+        (3, VOCLevel.MODERATE),
+    ],
+)
+def test_voc_level_to_text_maps_known_levels(raw, expected) -> None:
+    assert voc_level_to_text(raw) == expected
+
+
+@pytest.mark.parametrize("raw", ["0", "6", 0, 6])
+def test_voc_level_to_text_out_of_range_is_none(raw) -> None:
+    assert voc_level_to_text(raw) is None
+
+
+# --- battery_5step_to_pct --------------------------------------------------
+
+
+@pytest.mark.parametrize("empty", [None, ""])
+def test_battery_5step_to_pct_handles_empty(empty) -> None:
+    assert battery_5step_to_pct(empty) is None
+
+
+@pytest.mark.parametrize(
+    ("raw", "expected"),
+    [("0", 0), ("1", 20), ("2", 40), ("3", 60), ("4", 80), ("5", 100), (5, 100)],
+)
+def test_battery_5step_to_pct_scales_to_percentage(raw, expected) -> None:
+    assert battery_5step_to_pct(raw) == expected
+
+
+# --- remap_wslink_items connection gating ----------------------------------
+
+
+def test_remap_keeps_t9_group_when_connected() -> None:
+    out = remap_wslink_items({"t9cn": "1", "t9hcho": "57", "t9voclv": "5", "t9bat": "5", "t1tem": "11.3"})
+    assert out[HCHO] == "57"
+    assert out[VOC] == "5"
+    assert out[T9_BATTERY] == "5"
+    assert out[OUTSIDE_TEMP] == "11.3"
+
+
+@pytest.mark.parametrize("conn", [{"t9cn": "0"}, {}], ids=["disconnected", "absent"])
+def test_remap_drops_t9_group_when_disconnected_or_absent(conn) -> None:
+    out = remap_wslink_items({**conn, "t9hcho": "57", "t9voclv": "5", "t9bat": "5", "t1tem": "11.3"})
+    assert HCHO not in out
+    assert VOC not in out
+    assert T9_BATTERY not in out
+    # unrelated sensors are untouched by the gating
+    assert out[OUTSIDE_TEMP] == "11.3"
+
+
+def test_remap_issue_payload_exposes_t9_when_connected() -> None:
+    out = remap_wslink_items(ISSUE_PAYLOAD)
+    # t9cn == "1" -> the T9 sensors are exposed
+    assert out[HCHO] == "57"
+    assert out[VOC] == "5"
+    assert out[T9_BATTERY] == "5"
+    # connection flags never leak into the sensor data
+    assert "t9cn" not in out
+    assert "t9_conn" not in out
+
+
+# --- sensor entity descriptions -------------------------------------------
+
+
+@pytest.fixture
+def wslink_descriptions():
+    return {description.key: description for description in SENSOR_TYPES_WSLINK}
+
+
+def test_hcho_entity_description(wslink_descriptions) -> None:
+    description = wslink_descriptions[HCHO]
+    assert description.translation_key == HCHO
+    assert description.device_class is SensorDeviceClass.VOLATILE_ORGANIC_COMPOUNDS_PARTS
+    assert description.native_unit_of_measurement == CONCENTRATION_PARTS_PER_BILLION
+    assert description.state_class is SensorStateClass.MEASUREMENT
+    # value_fn is a pass-through (typing.cast is a no-op at runtime; HA coerces the str)
+    assert description.value_fn("57") == "57"
+
+
+def test_voc_entity_description(wslink_descriptions) -> None:
+    description = wslink_descriptions[VOC]
+    assert description.translation_key == VOC
+    assert description.device_class is SensorDeviceClass.ENUM
+    assert description.options == list(VOCLevel)
+    # ENUM sensors must not declare a state_class
+    assert description.state_class is None
+    assert description.value_fn("1") == VOCLevel.UNHEALTHY
+    assert description.value_fn("5") == "excellent"
+    assert description.value_fn(None) is None
+
+
+def test_t9_battery_entity_description(wslink_descriptions) -> None:
+    description = wslink_descriptions[T9_BATTERY]
+    assert description.translation_key == T9_BATTERY
+    assert description.device_class is SensorDeviceClass.BATTERY
+    assert description.native_unit_of_measurement == PERCENTAGE
+    assert description.state_class is SensorStateClass.MEASUREMENT
+    assert description.suggested_display_precision == 0
+    # no explicit icon -> HA renders the battery icon from the device class + %
+    assert description.icon is None
+    assert description.value_fn("5") == 100
+    assert description.value_fn("0") == 0
+    assert description.value_fn(None) is None
+
+
+# --- translation files -----------------------------------------------------
+
+_TRANSLATIONS_DIR = Path(__file__).resolve().parents[1] / "custom_components" / "sws12500" / "translations"
+
+
+@pytest.mark.parametrize("filename", ["en.json", "cs.json"])
+def test_translation_files_have_t9_entries(filename) -> None:
+    sensors = json.loads((_TRANSLATIONS_DIR / filename).read_text(encoding="utf-8"))["entity"]["sensor"]
+
+    assert sensors["hcho"]["name"]
+    assert sensors["t9_battery"]["name"]
+
+    voc = sensors["voc"]
+    assert voc["name"]
+    assert set(voc["state"]) == {member.value for member in VOCLevel}