Fix Growatt incorrect energy dashboard values for grid import (#82163)

* Fix Growatt incorrect energy dashboard values for grid import (#80905)

* Growatt - addressing review comments (#80905)

* Growatt - addressing more review comments (#80905)

homeassistant/components/growatt_server/sensor.py

@@ -159,7 +159,7 @@ class GrowattInverter(SensorEntity):
     @property
     def native_value(self):
         """Return the state of the sensor."""
-        result = self.probe.get_data(self.entity_description.api_key)
+        result = self.probe.get_data(self.entity_description)
         if self.entity_description.precision is not None:
             result = round(result, self.entity_description.precision)
         return result
@@ -168,7 +168,7 @@ class GrowattInverter(SensorEntity):
     def native_unit_of_measurement(self) -> str | None:
         """Return the unit of measurement of the sensor, if any."""
         if self.entity_description.currency:
-            return self.probe.get_data("currency")
+            return self.probe.get_currency()
         return super().native_unit_of_measurement
 
     def update(self) -> None:
@@ -187,6 +187,7 @@ class GrowattData:
         self.device_id = device_id
         self.plant_id = None
         self.data = {}
+        self.previous_values = {}
         self.username = username
         self.password = password
 
@@ -254,9 +255,61 @@ class GrowattData:
                     **mix_detail,
                     **dashboard_values_for_mix,
                 }
+            _LOGGER.debug(
+                "Finished updating data for %s (%s)",
+                self.device_id,
+                self.growatt_type,
+            )
         except json.decoder.JSONDecodeError:
             _LOGGER.error("Unable to fetch data from Growatt server")
 
-    def get_data(self, variable):
+    def get_currency(self):
+        """Get the currency."""
+        return self.data.get("currency")
+
+    def get_data(self, entity_description):
         """Get the data."""
-        return self.data.get(variable)
+        _LOGGER.debug(
+            "Data request for: %s",
+            entity_description.name,
+        )
+        variable = entity_description.api_key
+        api_value = self.data.get(variable)
+        previous_value = self.previous_values.get(variable)
+        return_value = api_value
+
+        # If we have a 'drop threshold' specified, then check it and correct if needed
+        if (
+            entity_description.previous_value_drop_threshold is not None
+            and previous_value is not None
+            and api_value is not None
+        ):
+            _LOGGER.debug(
+                "%s - Drop threshold specified (%s), checking for drop... API Value: %s, Previous Value: %s",
+                entity_description.name,
+                entity_description.previous_value_drop_threshold,
+                api_value,
+                previous_value,
+            )
+            diff = float(api_value) - float(previous_value)
+
+            # Check if the value has dropped (negative value i.e. < 0) and it has only dropped by a
+            # small amount, if so, use the previous value.
+            # Note - The energy dashboard takes care of drops within 10% of the current value,
+            # however if the value is low e.g. 0.2 and drops by 0.1 it classes as a reset.
+            if -(entity_description.previous_value_drop_threshold) <= diff < 0:
+                _LOGGER.debug(
+                    "Diff is negative, but only by a small amount therefore not a nightly reset, "
+                    "using previous value (%s) instead of api value (%s)",
+                    previous_value,
+                    api_value,
+                )
+                return_value = previous_value
+            else:
+                _LOGGER.debug(
+                    "%s - No drop detected, using API value", entity_description.name
+                )
+
+        self.previous_values[variable] = return_value
+
+        return return_value

homeassistant/components/growatt_server/sensor_types/mix.py

@@ -240,5 +240,6 @@ MIX_SENSOR_TYPES: tuple[GrowattSensorEntityDescription, ...] = (
         native_unit_of_measurement=ENERGY_KILO_WATT_HOUR,
         device_class=SensorDeviceClass.ENERGY,
         state_class=SensorStateClass.TOTAL_INCREASING,
+        previous_value_drop_threshold=0.2,
     ),
 )

homeassistant/components/growatt_server/sensor_types/sensor_entity_description.py

@@ -19,3 +19,4 @@ class GrowattSensorEntityDescription(SensorEntityDescription, GrowattRequiredKey
 
     precision: int | None = None
     currency: bool = False
+    previous_value_drop_threshold: float | None = None