Fixed bluetooth state changes for peripheral

Added code to detect bluetooth state changes for peripheral. Now initializePeripheral callback works as intended.
Upon bluetooth state change, gattServer has to be reinit or disposed depending on state.

Author: mattkhaw

src/android/BluetoothLePlugin.java

@@ -440,12 +440,7 @@ private void initializePeripheralAction(JSONArray args, CallbackContext callback
 
     initPeripheralCallback = callbackContext;
 
-    //Re-opening Gatt server seems to cause some issues
-    if (gattServer == null) {
-      Activity activity = cordova.getActivity();
-      BluetoothManager bluetoothManager = (BluetoothManager) activity.getSystemService(Context.BLUETOOTH_SERVICE);
-      gattServer = bluetoothManager.openGattServer(activity.getApplicationContext(), bluetoothGattServerCallback);
-    }
+    initGattServer();
 
     JSONObject returnObj = new JSONObject();
     addProperty(returnObj, keyStatus, statusEnabled);
@@ -2790,19 +2785,30 @@ public void onReceive(Context context, Intent intent) {
             }
             scanCallbackContext = null;
 
+            gattServer = null;
+
             pluginResult = new PluginResult(PluginResult.Status.OK, returnObj);
             pluginResult.setKeepCallback(true);
             initCallbackContext.sendPluginResult(pluginResult);
 
+            if (initPeripheralCallback != null) initPeripheralCallback.sendPluginResult(pluginResult);
+
+            break;
+          case BluetoothAdapter.STATE_TURNING_OFF:
+            gattServer.close();
             break;
           case BluetoothAdapter.STATE_ON:
 
             addProperty(returnObj, keyStatus, statusEnabled);
 
+            initGattServer();
+
             pluginResult = new PluginResult(PluginResult.Status.OK, returnObj);
             pluginResult.setKeepCallback(true);
             initCallbackContext.sendPluginResult(pluginResult);
 
+            if (initPeripheralCallback != null) initPeripheralCallback.sendPluginResult(pluginResult);
+
             break;
         }
       }
@@ -4536,4 +4542,13 @@ public void onServiceAdded(int status, BluetoothGattService service) {
       }
     }
   };
+
+  private void initGattServer() {
+    //Re-opening Gatt server seems to cause some issues
+    if (gattServer == null) {
+      Activity activity = cordova.getActivity();
+      BluetoothManager bluetoothManager = (BluetoothManager) activity.getSystemService(Context.BLUETOOTH_SERVICE);
+      gattServer = bluetoothManager.openGattServer(activity.getApplicationContext(), bluetoothGattServerCallback);
+    }
+  }
 }