Merge branch 'dev' into dev

Author: bastiaanv

plugins/eversense/src/main/kotlin/com/nightscout/eversense/models/EversenseState.kt

@@ -21,6 +21,7 @@ class EversenseState {
 
     var recentGlucoseDatetime: Long = 0
     var recentGlucoseValue: Int = 0
+    var lastGlucoseRaw: Int = 0
 
     var settings = EversenseTransmitterSettings()
 }

plugins/eversense/src/main/kotlin/com/nightscout/eversense/packets/Eversense365Communicator.kt

@@ -15,6 +15,7 @@ import com.nightscout.eversense.packets.e365.GetGlucoseDataPacket
 import com.nightscout.eversense.packets.e365.GetPatientSettingsPacket
 import com.nightscout.eversense.packets.e365.GetSensorInformationPacket
 import com.nightscout.eversense.packets.e365.SetCurrentDateTimePacket
+import com.nightscout.eversense.util.EselSmoothing
 import com.nightscout.eversense.util.EversenseLogger
 import com.nightscout.eversense.util.StorageKeys
 import kotlinx.serialization.json.Json
@@ -43,11 +44,17 @@ class Eversense365Communicator {
                 return
             }
 
+            var currentGlucose = glucoseData.glucoseInMgDl
+            if (state.useSmoothing && state.recentGlucoseValue > 0 && state.lastGlucoseRaw > 0) {
+                currentGlucose = EselSmoothing.smooth(currentGlucose, state.recentGlucoseValue, state.lastGlucoseRaw)
+            }
+
             val result = mutableListOf<EversenseCGMResult>()
             state.recentGlucoseDatetime = glucoseData.datetime
-            state.recentGlucoseValue = glucoseData.glucoseInMgDl
+            state.recentGlucoseValue = currentGlucose
+            state.lastGlucoseRaw = glucoseData.glucoseInMgDl
             result += EversenseCGMResult(
-                glucoseInMgDl = glucoseData.glucoseInMgDl,
+                glucoseInMgDl = currentGlucose,
                 datetime = glucoseData.datetime,
                 trend = glucoseData.trend
             )

plugins/eversense/src/main/kotlin/com/nightscout/eversense/packets/EversenseE3Communicator.kt

@@ -52,6 +52,7 @@ import com.nightscout.eversense.packets.e3.SetSettingRateFallingThresholdPacket
 import com.nightscout.eversense.packets.e3.SetSettingRateRisingEnabledPacket
 import com.nightscout.eversense.packets.e3.SetSettingRateRisingThresholdPacket
 import com.nightscout.eversense.packets.e3.SetSettingVibratePacket
+import com.nightscout.eversense.util.EselSmoothing
 import com.nightscout.eversense.util.EversenseLogger
 import com.nightscout.eversense.util.StorageKeys
 import kotlinx.serialization.json.Json
@@ -75,24 +76,30 @@ class EversenseE3Communicator {
 
             try {
                 EversenseLogger.debug(TAG, "Reading current glucose...")
-                val currentGlucose = gatt.writePacket<GetCurrentGlucosePacket.Response>(GetCurrentGlucosePacket())
-                if (currentGlucose.datetime <= state.recentGlucoseDatetime) {
-                    EversenseLogger.warning(TAG, "Glucose data is still recent after reading - currentReading: ${currentGlucose.datetime}, lastReading: ${state.recentGlucoseDatetime}")
+                val glucoseData = gatt.writePacket<GetCurrentGlucosePacket.Response>(GetCurrentGlucosePacket())
+                if (glucoseData.datetime <= state.recentGlucoseDatetime) {
+                    EversenseLogger.warning(TAG, "Glucose data is still recent after reading - currentReading: ${glucoseData.datetime}, lastReading: ${state.recentGlucoseDatetime}")
                     return
                 }
 
-                if (currentGlucose.glucoseInMgDl > 1000) {
-                    EversenseLogger.error(TAG, "recentGlucose exceeds range - received: ${currentGlucose.glucoseInMgDl}")
+                if (glucoseData.glucoseInMgDl > 1000) {
+                    EversenseLogger.error(TAG, "recentGlucose exceeds range - received: ${glucoseData.glucoseInMgDl}")
                     return
                 }
 
+                var currentGlucose = glucoseData.glucoseInMgDl
+                if (state.useSmoothing && state.recentGlucoseValue > 0 && state.lastGlucoseRaw > 0) {
+                    currentGlucose = EselSmoothing.smooth(currentGlucose, state.recentGlucoseValue, state.lastGlucoseRaw)
+                }
+
                 val result = mutableListOf<EversenseCGMResult>()
-                state.recentGlucoseDatetime = currentGlucose.datetime
-                state.recentGlucoseValue = currentGlucose.glucoseInMgDl
+                state.recentGlucoseDatetime = glucoseData.datetime
+                state.recentGlucoseValue = currentGlucose
+                state.lastGlucoseRaw = glucoseData.glucoseInMgDl
                 result += EversenseCGMResult(
-                    glucoseInMgDl = currentGlucose.glucoseInMgDl,
-                    datetime = currentGlucose.datetime,
-                    trend = currentGlucose.trend
+                    glucoseInMgDl = currentGlucose,
+                    datetime = glucoseData.datetime,
+                    trend = glucoseData.trend
                 )
 
                 // TODO: read history for backfill

plugins/eversense/src/main/kotlin/com/nightscout/eversense/util/EselSmoothing.kt

@@ -0,0 +1,33 @@
+package com.nightscout.eversense.util
+
+import kotlin.math.min
+import kotlin.math.round
+
+class EselSmoothing {
+    companion object {
+        private const val factor: Double = 0.3
+        private const val correction: Double = 0.5
+        private const val descent_factor: Double = 0.0
+
+        fun smooth(currentRaw: Int, lastSmooth: Int, lastRaw: Int): Int {
+            val value = currentRaw.toDouble()
+
+            // exponential smoothing, see https://en.wikipedia.org/wiki/Exponential_smoothing
+            // y'[t]=y'[t-1] + (a*(y-y'[t-1])) = a*y+(1-a)*y'[t-1]
+            // factor is a, value is y, lastSmooth y'[t-1], smooth y'
+            // factor between 0 and 1, default 0.3
+            // factor = 0: always last smooth (constant)
+            // factor = 1: no smoothing
+            var smooth: Double = lastSmooth + (factor * (value - lastSmooth))
+
+            // correction: average of delta between raw and smooth value, added to smooth with correction factor
+            // correction between 0 and 1, default 0.5
+            // correction = 0: no correction, full smoothing
+            // correction > 0: less smoothing
+            smooth += (correction * ((lastRaw - lastSmooth) + (value - smooth)) / 2.0)
+            smooth -= descent_factor * (smooth - min(value, smooth))
+
+            return round(smooth).toInt()
+        }
+    }
+}