This commit expands the OneByoneHandler to support Eufy C1 (T9146) and Eufy P1 (T9147) scales. It also implements battery level monitoring by subscribing to the battery service and notifying the user when the battery level is low, see #1278

Author: oliexdev

android_app/app/src/main/java/com/health/openscale/core/bluetooth/scales/OneByoneHandler.kt

@@ -49,6 +49,8 @@ class OneByoneHandler : ScaleDeviceHandler() {
     private val SVC_FFF0  = uuid16(0xFFF0)
     private val CHR_FFF4  = uuid16(0xFFF4) // NOTIFY: mixed weight/body payloads (CF ...)
     private val CHR_FFF1  = uuid16(0xFFF1) // WRITE: command pipe (FD/ F1/ F2 ...)
+    private val SVC_180F = uuid16(0x180F) //battery service
+    private val CHR_2A19 = uuid16(0x2A19) //battery characteristic
 
     // --- Small runtime state ---------------------------------------------------
 
@@ -64,8 +66,13 @@ class OneByoneHandler : ScaleDeviceHandler() {
 
     override fun supportFor(device: ScannedDeviceInfo): DeviceSupport? {
         val name = device.name.lowercase()
-        val supports = name.equals("Health Scale".lowercase())
-        if (!supports) return null
+
+        val model = when {
+            "t9146" in name -> "Eufy C1"
+            "t9147" in name -> "Eufy P1"
+            "Health Scale".lowercase() in name -> "1byone (classic)"
+            else -> return null
+        }
 
         val caps = buildSet {
             add(DeviceCapability.BODY_COMPOSITION)
@@ -76,7 +83,7 @@ class OneByoneHandler : ScaleDeviceHandler() {
         }
 
         return DeviceSupport(
-            displayName = "1byone (classic)",
+            displayName = model,
             capabilities = caps,
             implemented  = caps,
             linkMode = LinkMode.CONNECT_GATT
@@ -97,15 +104,28 @@ class OneByoneHandler : ScaleDeviceHandler() {
         waitAckClock = true
         writeTo(SVC_FFF0, CHR_FFF1, clock)
 
+        // 1) Battery: subscribe + read once
+        setNotifyOn(SVC_180F, CHR_2A19)
+        readFrom(SVC_180F, CHR_2A19)
+
         // NOTE: After we receive the ACK, we will request history (F2 00) in onNotification().
     }
 
     override fun onNotification(characteristic: UUID, data: ByteArray, user: ScaleUser) {
-        if (characteristic != CHR_FFF4) {
+        if (characteristic != CHR_FFF4 && characteristic != CHR_2A19) {
             logD("Unexpected notify from $characteristic ${data.toHexPreview(24)}")
             return
         }
 
+        if (characteristic == CHR_2A19) {
+            val level = (data.first().toInt() and 0xFF)
+            logD("Reported battery level: $level%")
+            if (level <= 10) {
+                userWarn(R.string.bluetooth_scale_warning_low_battery, level)
+            }
+            return
+        }
+
         // Two-byte ACKs appear during setup:
         if (data.size == 2) {
             when {