announce peer ID in servicedata to prevent duplicate connections (#613)

app/src/main/java/com/bitchat/android/mesh/BluetoothConnectionManager.kt

@@ -70,7 +70,7 @@ class BluetoothConnectionManager(
     }
     
     private val serverManager = BluetoothGattServerManager(
-        context, connectionScope, connectionTracker, permissionManager, powerManager, componentDelegate
+        context, connectionScope, connectionTracker, permissionManager, powerManager, componentDelegate, myPeerID
     )
     private val clientManager = BluetoothGattClientManager(
         context, connectionScope, connectionTracker, permissionManager, powerManager, componentDelegate

app/src/main/java/com/bitchat/android/mesh/BluetoothConnectionTracker.kt

@@ -51,7 +51,8 @@ class BluetoothConnectionTracker(
         val characteristic: BluetoothGattCharacteristic? = null,
         val rssi: Int = Int.MIN_VALUE,
         val isClient: Boolean = false,
-        val connectedAt: Long = System.currentTimeMillis()
+        val connectedAt: Long = System.currentTimeMillis(),
+        val peerID: String? = null
     )
     
     /**
@@ -170,6 +171,14 @@ class BluetoothConnectionTracker(
     fun isDeviceConnected(deviceAddress: String): Boolean {
         return connectedDevices.containsKey(deviceAddress)
     }
+
+    /**
+     * Check if a peer is already connected (by PeerID)
+     */
+    fun isPeerConnected(peerID: String): Boolean {
+        // Only consider actual connected devices that have identified themselves
+        return connectedDevices.values.any { it.peerID == peerID }
+    }
     
     /**
      * Check if connection attempt is allowed

app/src/main/java/com/bitchat/android/mesh/BluetoothGattClientManager.kt

@@ -320,6 +320,22 @@ class BluetoothGattClientManager(
             return
         }
 
+        // Try to extract peerID from Service Data (if available) for stable identity
+        val serviceData = scanRecord?.getServiceData(ParcelUuid(AppConstants.Mesh.Gatt.SERVICE_UUID))
+        val peerID = if (serviceData != null && serviceData.size >= 8) {
+            serviceData.joinToString("") { "%02x".format(it) }
+        } else {
+            null
+        }
+
+        if (peerID != null) {
+            // Log.v(TAG, "Found peerID $peerID in scan record for $deviceAddress")
+            if (connectionTracker.isPeerConnected(peerID)) {
+                 Log.d(TAG, "Deduplication: Peer $peerID is already connected (ignoring $deviceAddress)")
+                 return
+            }
+        }
+
         // Log.d(TAG, "Received scan result from $deviceAddress - already connected: ${connectionTracker.isDeviceConnected(deviceAddress)}")
         
         // Store RSSI from scan results for later use (especially for server connections)
@@ -332,7 +348,7 @@ class BluetoothGattClientManager(
                     deviceName = device.name,
                     deviceAddress = deviceAddress,
                     rssi = rssi,
-                    peerID = null // peerID unknown at scan time
+                    peerID = peerID // Use the discovered peerID if available
                 )
             )
         } catch (_: Exception) { }
@@ -342,13 +358,12 @@ class BluetoothGattClientManager(
             Log.d(TAG, "Skipping device $deviceAddress due to weak signal: $rssi < ${powerManager.getRSSIThreshold()}")
             // Even if we skip connecting, still publish scan result to debug UI
             try {
-                val pid: String? = null // We don't know peerID until packet exchange
                 DebugSettingsManager.getInstance().addScanResult(
                     DebugScanResult(
                         deviceName = device.name,
                         deviceAddress = deviceAddress,
                         rssi = rssi,
-                        peerID = pid
+                        peerID = peerID
                     )
                 )
             } catch (_: Exception) { }
@@ -373,7 +388,7 @@ class BluetoothGattClientManager(
         
         // Add pending connection and start connection
         if (connectionTracker.addPendingConnection(deviceAddress)) {
-            connectToDevice(device, rssi)
+            connectToDevice(device, rssi, peerID)
         }
     }
     
@@ -381,11 +396,11 @@ class BluetoothGattClientManager(
      * Connect to a device as GATT client
      */
     @Suppress("DEPRECATION")
-    private fun connectToDevice(device: BluetoothDevice, rssi: Int) {
+    private fun connectToDevice(device: BluetoothDevice, rssi: Int, peerID: String? = null) {
         if (!permissionManager.hasBluetoothPermissions()) return
 
         val deviceAddress = device.address
-        Log.i(TAG, "Connecting to bitchat device: $deviceAddress")
+        Log.i(TAG, "Connecting to bitchat device: $deviceAddress (peerID: $peerID)")
         
         val gattCallback = object : BluetoothGattCallback() {
             override fun onConnectionStateChange(gatt: BluetoothGatt, status: Int, newState: Int) {
@@ -435,7 +450,8 @@ class BluetoothGattClientManager(
                         device = gatt.device,
                         gatt = gatt,
                         rssi = rssi,
-                        isClient = true
+                        isClient = true,
+                        peerID = peerID // Store the peerID discovered during scan
                     )
                     connectionTracker.addDeviceConnection(deviceAddress, deviceConn)
                     

app/src/main/java/com/bitchat/android/mesh/BluetoothGattServerManager.kt

@@ -24,7 +24,8 @@ class BluetoothGattServerManager(
     private val connectionTracker: BluetoothConnectionTracker,
     private val permissionManager: BluetoothPermissionManager,
     private val powerManager: PowerManager,
-    private val delegate: BluetoothConnectionManagerDelegate?
+    private val delegate: BluetoothConnectionManagerDelegate?,
+    private val myPeerID: String
 ) {
     
     companion object {
@@ -372,13 +373,27 @@ class BluetoothGattServerManager(
             .setIncludeTxPowerLevel(false)
             .setIncludeDeviceName(false)
             .build()
+            
+        // Add stable identity (first 8 bytes of peerID) to Scan Response
+        // This allows scanners to deduplicate devices even if MAC address rotates
+        val peerIDBytes = try {
+            myPeerID.chunked(2).map { it.toInt(16).toByte() }.toByteArray().take(8).toByteArray()
+        } catch (e: Exception) {
+            ByteArray(0)
+        }
+        
+        val scanResponse = AdvertiseData.Builder()
+            .addServiceData(ParcelUuid(AppConstants.Mesh.Gatt.SERVICE_UUID), peerIDBytes)
+            .setIncludeTxPowerLevel(false)
+            .setIncludeDeviceName(false)
+            .build()
         
         advertiseCallback = object : AdvertiseCallback() {
             override fun onStartSuccess(settingsInEffect: AdvertiseSettings) {
                 val mode = try {
                     powerManager.getPowerInfo().split("Current Mode: ")[1].split("\n")[0]
                 } catch (_: Exception) { "unknown" }
-                Log.i(TAG, "Advertising started (power mode: $mode)")
+                Log.i(TAG, "Advertising started (power mode: $mode) with stable ID: ${peerIDBytes.joinToString("") { "%02x".format(it) }}")
             }
             
             override fun onStartFailure(errorCode: Int) {
@@ -387,7 +402,7 @@ class BluetoothGattServerManager(
         }
         
         try {
-            bleAdvertiser.startAdvertising(settings, data, advertiseCallback)
+            bleAdvertiser.startAdvertising(settings, data, scanResponse, advertiseCallback)
         } catch (se: SecurityException) {
             Log.e(TAG, "SecurityException starting advertising (missing permission?): ${se.message}")
         } catch (e: Exception) {