Add Nightscout integration (#38615)

* Implement NightScout sensor integration

* Add tests for NightScout integration

* Fix Nightscout captalization

* Change quality scale for Nightscout

* Trigger actions

* Add missing tests

* Fix stale comments

* Fix Nightscout manufacturer

* Add entry type service

* Change host to URL on nightscout config flow

* Add ConfigEntryNotReady exception to nighscout init

* Remote platform_schema from nightscout sensor

* Update homeassistant/components/nightscout/config_flow.py

Co-authored-by: Chris Talkington <chris@talkingtontech.com>

Co-authored-by: Chris Talkington <chris@talkingtontech.com>

homeassistant/components/nightscout/sensor.py

@@ -0,0 +1,126 @@
+"""Support for Nightscout sensors."""
+from asyncio import TimeoutError as AsyncIOTimeoutError
+from datetime import timedelta
+import hashlib
+import logging
+from typing import Callable, List
+
+from aiohttp import ClientError
+from py_nightscout import Api as NightscoutAPI
+
+from homeassistant.config_entries import ConfigEntry
+from homeassistant.core import HomeAssistant
+from homeassistant.helpers.entity import Entity
+
+from .const import ATTR_DATE, ATTR_DELTA, ATTR_DEVICE, ATTR_DIRECTION, ATTR_SVG, DOMAIN
+
+SCAN_INTERVAL = timedelta(minutes=1)
+
+_LOGGER = logging.getLogger(__name__)
+
+DEFAULT_NAME = "Blood Glucose"
+
+
+async def async_setup_entry(
+    hass: HomeAssistant,
+    entry: ConfigEntry,
+    async_add_entities: Callable[[List[Entity], bool], None],
+) -> None:
+    """Set up the Glucose Sensor."""
+    api = hass.data[DOMAIN][entry.entry_id]
+    async_add_entities([NightscoutSensor(api, "Blood Sugar")], True)
+
+
+class NightscoutSensor(Entity):
+    """Implementation of a Nightscout sensor."""
+
+    def __init__(self, api: NightscoutAPI, name):
+        """Initialize the Nightscout sensor."""
+        self.api = api
+        self._unique_id = hashlib.sha256(api.server_url.encode("utf-8")).hexdigest()
+        self._name = name
+        self._state = None
+        self._attributes = None
+        self._unit_of_measurement = "mg/dL"
+        self._icon = "mdi:cloud-question"
+        self._available = False
+
+    @property
+    def unique_id(self):
+        """Return the unique ID of the sensor."""
+        return self._unique_id
+
+    @property
+    def name(self):
+        """Return the name of the sensor."""
+        return self._name
+
+    @property
+    def unit_of_measurement(self):
+        """Return the unit the value is expressed in."""
+        return self._unit_of_measurement
+
+    @property
+    def available(self):
+        """Return if the sensor data are available."""
+        return self._available
+
+    @property
+    def state(self):
+        """Return the state of the device."""
+        return self._state
+
+    @property
+    def icon(self):
+        """Return the icon to use in the frontend, if any."""
+        return self._icon
+
+    @property
+    def should_poll(self):
+        """Return the polling state."""
+        return True
+
+    async def async_update(self):
+        """Fetch the latest data from Nightscout REST API and update the state."""
+        try:
+            values = await self.api.get_sgvs()
+        except (ClientError, AsyncIOTimeoutError, OSError) as error:
+            _LOGGER.error("Error fetching data. Failed with %s", error)
+            self._available = False
+            return
+
+        self._available = True
+        self._attributes = {}
+        self._state = None
+        if values:
+            value = values[0]
+            self._attributes = {
+                ATTR_DEVICE: value.device,
+                ATTR_DATE: value.date,
+                ATTR_SVG: value.sgv,
+                ATTR_DELTA: value.delta,
+                ATTR_DIRECTION: value.direction,
+            }
+            self._state = value.sgv
+            self._icon = self._parse_icon()
+        else:
+            self._available = False
+            _LOGGER.warning("Empty reply found when expecting JSON data")
+
+    def _parse_icon(self) -> str:
+        """Update the icon based on the direction attribute."""
+        switcher = {
+            "Flat": "mdi:arrow-right",
+            "SingleDown": "mdi:arrow-down",
+            "FortyFiveDown": "mdi:arrow-bottom-right",
+            "DoubleDown": "mdi:chevron-triple-down",
+            "SingleUp": "mdi:arrow-up",
+            "FortyFiveUp": "mdi:arrow-top-right",
+            "DoubleUp": "mdi:chevron-triple-up",
+        }
+        return switcher.get(self._attributes[ATTR_DIRECTION], "mdi:cloud-question")
+
+    @property
+    def device_state_attributes(self):
+        """Return the state attributes."""
+        return self._attributes