Add manual disconnect

This allows going back to the connection page and to choose a different
server. Furthermore it might be useful to force a new connection attempt
while auto-reconnect might be in a delay state.

1 files changed, 12 insertions, 1 deletions

diff --git a/lib/data.dart b/lib/data.dart
index 89d8760..415e61e 100644
--- a/lib/data.dart
+++ b/lib/data.dart
@@ -21,11 +21,14 @@ class AppState with ChangeNotifier {
     MachineState.init: <MachineEvent, MachineState> {
       MachineEvent.connect: MachineState.disconnected,
     },
+    MachineState.disconnected: <MachineEvent, MachineState> {
+      MachineEvent.disconnect: MachineState.init,
+    },
   };
   MachineState state = MachineState.init;
 
   Map<String, bool> contacts = <String, bool>{};
-  late final MqttServerClient _client;
+  late MqttServerClient _client;
   bool _brokerConnected = false;
   bool get brokerConnected => _brokerConnected;
   bool _serverConnected = false;
@@ -54,6 +57,10 @@ class AppState with ChangeNotifier {
       _initMqtt();
     }
 
+    if (nextState == MachineState.init) {
+      _deinitMqtt();
+    }
+
     state = nextState;
     notifyListeners();
   }
@@ -91,6 +98,10 @@ class AppState with ChangeNotifier {
     _client.updates?.listen(_onMessage);
   }
 
+  void _deinitMqtt() {
+    _client.disconnect();
+  }
+
   void _onConnected() {
     _client.subscribe('$topicPrefix/contact/+/state', MqttQos.exactlyOnce);
     _client.subscribe('$topicPrefix/server/health', MqttQos.exactlyOnce);