BLE: decode cadence from cycling powermeter.

Part of #1352.

src/androidTest/java/de/dennisguse/opentracks/sensors/BluetoothUtilsTest.java

@@ -11,6 +11,7 @@ import de.dennisguse.opentracks.data.models.Cadence;
 import de.dennisguse.opentracks.data.models.Distance;
 import de.dennisguse.opentracks.data.models.Speed;
 import de.dennisguse.opentracks.sensors.sensorData.SensorDataCycling;
+import de.dennisguse.opentracks.sensors.sensorData.SensorDataCyclingPower;
 import de.dennisguse.opentracks.sensors.sensorData.SensorDataRunning;
 
 public class BluetoothUtilsTest {
@@ -86,10 +87,25 @@ public class BluetoothUtilsTest {
         characteristic.setValue(new byte[]{0, 0, 40, 0});
 
         // when
-        int power_w = BluetoothUtils.parseCyclingPower(characteristic);
+        SensorDataCyclingPower.Data powerCadence = BluetoothUtils.parseCyclingPower(characteristic);
 
         // then
-        assertEquals(40, power_w);
+        assertEquals(40, powerCadence.getPower().getW(), 0.01);
+    }
+
+    @Test
+    public void parseCyclingPower_power_with_cadence() {
+        BluetoothGattCharacteristic characteristic = new BluetoothGattCharacteristic(BluetoothUtils.CYCLING_POWER.getServiceUUID(), 0, 0);
+        characteristic.setValue(new byte[]{0x2C, 0x00, 0x00, 0x00, (byte) 0x9F, 0x00, 0x0C, 0x00, (byte) 0xE5, 0x42});
+
+        // when
+        SensorDataCyclingPower.Data powerCadence = BluetoothUtils.parseCyclingPower(characteristic);
+
+        // then
+        assertEquals(0, powerCadence.getPower().getW(), 0.01);
+
+        assertEquals(12, powerCadence.getCadence().getCrankRevolutionsCount());
+        assertEquals(17125, powerCadence.getCadence().getCrankRevolutionsTime());
     }
 
     @Test

src/main/java/de/dennisguse/opentracks/sensors/BluetoothConnectionManager.java

@@ -254,9 +254,9 @@ public abstract class BluetoothConnectionManager<DataType> {
 
         @Override
         protected SensorDataCyclingPower parsePayload(String sensorName, String address, BluetoothGattCharacteristic characteristic) {
-            Integer cyclingPower = BluetoothUtils.parseCyclingPower(characteristic);
+            SensorDataCyclingPower.Data cyclingPower = BluetoothUtils.parseCyclingPower(characteristic);
 
-            return cyclingPower != null ? new SensorDataCyclingPower(address, sensorName, Power.of(cyclingPower)) : null;
+            return cyclingPower != null ? new SensorDataCyclingPower(address, sensorName, cyclingPower.getPower()) : null;
         }
     }
 

src/main/java/de/dennisguse/opentracks/sensors/BluetoothUtils.java

@@ -30,8 +30,10 @@ import java.util.UUID;
 
 import de.dennisguse.opentracks.data.models.Cadence;
 import de.dennisguse.opentracks.data.models.Distance;
+import de.dennisguse.opentracks.data.models.Power;
 import de.dennisguse.opentracks.data.models.Speed;
 import de.dennisguse.opentracks.sensors.sensorData.SensorDataCycling;
+import de.dennisguse.opentracks.sensors.sensorData.SensorDataCyclingPower;
 import de.dennisguse.opentracks.sensors.sensorData.SensorDataRunning;
 
 /**
@@ -109,14 +111,45 @@ public class BluetoothUtils {
         return null;
     }
 
-    public static Integer parseCyclingPower(BluetoothGattCharacteristic characteristic) {
+    public static SensorDataCyclingPower.Data parseCyclingPower(BluetoothGattCharacteristic characteristic) {
         // DOCUMENTATION https://www.bluetooth.com/wp-content/uploads/Sitecore-Media-Library/Gatt/Xml/Characteristics/org.bluetooth.characteristic.cycling_power_measurement.xml
         int valueLength = characteristic.getValue().length;
-        if (valueLength < 4) {
+        if (valueLength == 0) {
             return null;
         }
 
-        return characteristic.getIntValue(BluetoothGattCharacteristic.FORMAT_SINT16, 2);
+        int index = 0;
+        int flags1 = characteristic.getIntValue(BluetoothGattCharacteristic.FORMAT_UINT8, index++);
+        int flags2 = characteristic.getIntValue(BluetoothGattCharacteristic.FORMAT_UINT8, index++);
+        boolean hasPedalPowerBalance = (flags1 & 0x01) > 0;
+        boolean hasAccumulatedTorque = (flags1 & 0x04) > 0;
+        boolean hasWheel = (flags1 & 16) > 0;
+        boolean hasCrank = (flags1 & 32) > 0;
+
+        Integer instantaneousPower = characteristic.getIntValue(BluetoothGattCharacteristic.FORMAT_SINT16, index);
+        index += 2;
+
+        if (hasPedalPowerBalance) {
+            index += 1;
+        }
+        if (hasAccumulatedTorque) {
+            index += 2;
+        }
+        if (hasWheel) {
+            index += 2 + 2;
+        }
+
+        SensorDataCycling.CyclingCadence cadence = null;
+        if (hasCrank && valueLength - index >= 4) {
+            long crankCount = characteristic.getIntValue(BluetoothGattCharacteristic.FORMAT_UINT16, index);
+            index += 2;
+
+            int crankTime = characteristic.getIntValue(BluetoothGattCharacteristic.FORMAT_UINT16, index); // 1/1024s
+
+            cadence = new SensorDataCycling.CyclingCadence("", "", crankCount, crankTime);
+        }
+
+        return new SensorDataCyclingPower.Data(Power.of(instantaneousPower), cadence);
     }
 
     public static SensorDataCycling.CadenceAndSpeed parseCyclingCrankAndWheel(String address, String sensorName, @NonNull BluetoothGattCharacteristic characteristic) {

src/main/java/de/dennisguse/opentracks/sensors/sensorData/SensorDataCycling.java

@@ -40,13 +40,6 @@ public final class SensorDataCycling {
             this.crankRevolutionsTime = crankRevolutionsTime;
         }
 
-        /**
-         * Workaround for Wahoo CADENCE: provides speed instead of cadence
-         */
-        public CyclingCadence(@NonNull DistanceSpeed speed) {
-            this(speed.getSensorAddress(), speed.getSensorName(), speed.wheelRevolutionsCount, speed.wheelRevolutionsTime);
-        }
-
         public boolean hasData() {
             return crankRevolutionsCount != null && crankRevolutionsTime != null;
         }

src/main/java/de/dennisguse/opentracks/sensors/sensorData/SensorDataCyclingPower.java

@@ -1,6 +1,7 @@
 package de.dennisguse.opentracks.sensors.sensorData;
 
 import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
 
 import de.dennisguse.opentracks.data.models.Power;
 
@@ -17,13 +18,40 @@ public class SensorDataCyclingPower extends SensorData<Power> {
 
     @NonNull
     @Override
-    public String toString() {
+    protected Power getNoneValue() {
-        return super.toString() + " power=" + value;
+        return Power.of(0f);
     }
 
     @NonNull
     @Override
-    protected Power getNoneValue() {
+    public String toString() {
-        return Power.of(0f);
+        return super.toString() + " data=" + value;
+    }
+
+    public static class Data {
+        private final Power power;
+        private final SensorDataCycling.CyclingCadence cadence;
+
+        public Data(Power power, @Nullable SensorDataCycling.CyclingCadence cadence) {
+            this.power = power;
+            this.cadence = cadence;
+        }
+
+        public Power getPower() {
+            return power;
+        }
+
+        public SensorDataCycling.CyclingCadence getCadence() {
+            return cadence;
+        }
+
+        @NonNull
+        @Override
+        public String toString() {
+            return "Data{" +
+                    "power=" + power +
+                    ", cadence=" + cadence +
+                    '}';
+        }
     }
 }