supported body measurements for Yunmai scale

android_app/app/src/main/java/com/health/openscale/core/bluetooth/BluetoothYunmaiSE_Mini.java

@@ -23,6 +23,7 @@ import android.content.SharedPreferences;
 import android.preference.PreferenceManager;
 
 import com.health.openscale.core.OpenScale;
+import com.health.openscale.core.bluetooth.lib.YunmaiLib;
 import com.health.openscale.core.datatypes.ScaleMeasurement;
 import com.health.openscale.core.datatypes.ScaleUser;
 import com.health.openscale.core.utils.Converters;
@@ -31,6 +32,8 @@ import java.util.Date;
 import java.util.Random;
 import java.util.UUID;
 
+import timber.log.Timber;
+
 public class BluetoothYunmaiSE_Mini extends BluetoothCommunication {
     private final UUID WEIGHT_MEASUREMENT_SERVICE = UUID.fromString("0000ffe0-0000-1000-8000-00805f9b34fb");
     private final UUID WEIGHT_MEASUREMENT_CHARACTERISTIC = UUID.fromString("0000ffe4-0000-1000-8000-00805f9b34fb");
@@ -119,7 +122,7 @@ public class BluetoothYunmaiSE_Mini extends BluetoothCommunication {
     }
 
     private void parseBytes(byte[] weightBytes) {
-        final ScaleUser selectedUser = OpenScale.getInstance().getSelectedScaleUser();
+        final ScaleUser scaleUser = OpenScale.getInstance().getSelectedScaleUser();
 
         ScaleMeasurement scaleBtData = new ScaleMeasurement();
 
@@ -130,8 +133,26 @@ public class BluetoothYunmaiSE_Mini extends BluetoothCommunication {
         scaleBtData.setWeight(weight);
 
         if (isMini) {
-            float fat = Converters.fromUnsignedInt16Be(weightBytes, 17) / 100.0f;
-            scaleBtData.setFat(fat);
+            int sex;
+
+            if (scaleUser.getGender() == Converters.Gender.MALE) {
+                sex = 1;
+            } else {
+                sex = 0;
+            }
+
+            YunmaiLib yunmaiLib = new YunmaiLib(sex, scaleUser.getBodyHeight());
+            float bodyFat = Converters.fromUnsignedInt16Be(weightBytes, 17) / 100.0f;
+            int resistance = Converters.fromUnsignedInt16Be(weightBytes, 15);
+            scaleBtData.setFat(bodyFat);
+            scaleBtData.setMuscle(yunmaiLib.getMuscle(bodyFat));
+            scaleBtData.setWater(yunmaiLib.getWater(bodyFat));
+            scaleBtData.setBone(yunmaiLib.getBoneMass(scaleBtData.getMuscle(), weight));
+
+            Timber.d("received bytes [%s]", byteInHex(weightBytes));
+            Timber.d("received decrypted bytes [weight: %.2f, fat: %.2f, resistance: %d]", weight, bodyFat, resistance);
+            Timber.d("user [%s]", scaleUser);
+            Timber.d("scale measurement [%s]", scaleBtData);
         }
 
         addScaleData(scaleBtData);

android_app/app/src/main/java/com/health/openscale/core/bluetooth/lib/YunmaiLib.java

@@ -0,0 +1,60 @@
+/* Copyright (C) 2018  olie.xdev <olie.xdev@googlemail.com>
+ *
+ *    This program is free software: you can redistribute it and/or modify
+ *    it under the terms of the GNU General Public License as published by
+ *    the Free Software Foundation, either version 3 of the License, or
+ *    (at your option) any later version.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU General Public License for more details.
+ *
+ *    You should have received a copy of the GNU General Public License
+ *    along with this program.  If not, see <http://www.gnu.org/licenses/>
+ */
+
+package com.health.openscale.core.bluetooth.lib;
+
+public class YunmaiLib {
+    private int sex; // male = 1; female = 0
+    private float height;
+
+    public YunmaiLib(int sex, float height) {
+        this.sex = sex;
+        this.height = height;
+    }
+
+    public float getWater(float bodyFat) {
+        return ((100.0f - bodyFat) * 0.726f * 100.0f + 0.5f) / 100.0f;
+    }
+
+    public float getMuscle(float bodyFat) {
+        float muscle;
+        muscle = (100.0f - bodyFat) * 0.67f;
+
+        if (sex == 1) {
+            muscle = (100.0f - bodyFat) * 0.7f;
+        }
+
+        muscle = ((muscle * 100.0f) + 0.5f) / 100.0f;
+
+        return muscle;
+    }
+
+    public float getBoneMass(float muscle, float weight) {
+        float boneMass;
+
+        float h = height - 170.0f;
+
+        if (sex == 1) {
+            boneMass = ((weight * (muscle  / 100.0f) * 4.0f) / 7.0f * 0.22f * 0.6f) + (h / 100.0f);
+        } else {
+            boneMass = ((weight * (muscle  / 100.0f) * 4.0f) / 7.0f * 0.34f * 0.45f) + (h / 100.0f);
+        }
+
+        boneMass = ((boneMass * 10.0f) + 0.5f) / 10.0f;
+
+        return boneMass;
+    }
+}