feat: add mqtt feature

Signed-off-by: Sayan Paul <[email protected]>

lib/mqtt/mqtt.dart

@@ -0,0 +1,118 @@
+import 'dart:convert';
+import 'dart:ffi';
+import 'package:flutter/foundation.dart';
+import 'package:flutter/material.dart';
+import 'package:mqtt_client/mqtt_client.dart';
+import 'package:mqtt_client/mqtt_server_client.dart';
+
+class MqttHandler with ChangeNotifier {
+  final ValueNotifier<String> data = ValueNotifier<String>("");
+  late MqttServerClient client;
+
+  Future<Object> connect() async {
+    client = MqttServerClient.withPort(
+        'broker.hivemq.com', 'smartpump239834893453920938', 1883);
+    client.logging(on: true);
+    client.onConnected = onConnected;
+    client.onDisconnected = onDisconnected;
+    client.onUnsubscribed = onUnsubscribed;
+    client.onSubscribed = onSubscribed;
+    client.onSubscribeFail = onSubscribeFail;
+    client.pongCallback = pong;
+    client.keepAlivePeriod = 60;
+    client.logging(on: true);
+
+    /// Set the correct MQTT protocol for mosquito
+    client.setProtocolV311();
+
+    final connMessage = MqttConnectMessage()
+        .withWillTopic('willtopic')
+        .withWillMessage('Will message')
+        .startClean()
+        .withWillQos(MqttQos.atLeastOnce);
+
+    print('MQTT_LOGS::Mosquitto client connecting....');
+
+    client.connectionMessage = connMessage;
+    try {
+      await client.connect();
+    } catch (e) {
+      print('Exception: $e');
+      client.disconnect();
+    }
+
+    if (client.connectionStatus!.state == MqttConnectionState.connected) {
+      print('MQTT_LOGS::Mosquitto client connected');
+    } else {
+      print(
+          'MQTT_LOGS::ERROR Mosquitto client connection failed - disconnecting, status is ${client.connectionStatus}');
+      client.disconnect();
+      return -1;
+    }
+
+    //wil be used to determine water tank status
+    print('MQTT_LOGS::Subscribing to the pump/current topic');
+    const topic = 'pump/current';
+    client.subscribe(topic, MqttQos.atMostOnce);
+
+    client.updates!.listen((List<MqttReceivedMessage<MqttMessage?>>? c) {
+      final recMess = c![0].payload as MqttPublishMessage;
+      final pt =
+          MqttPublishPayload.bytesToStringAsString(recMess.payload.message);
+
+      data.value = pt;
+      notifyListeners();
+      print(
+          'MQTT_LOGS:: New data arrived: topic is <${c[0].topic}>, payload is $pt');
+      print('');
+    });
+
+    return client;
+  }
+
+  void onConnected() {
+    print('MQTT_LOGS:: Connected');
+  }
+
+  void onDisconnected() {
+    print('MQTT_LOGS:: Disconnected');
+  }
+
+  void onSubscribed(String topic) {
+    print('MQTT_LOGS:: Subscribed topic: $topic');
+  }
+
+  void onSubscribeFail(String topic) {
+    print('MQTT_LOGS:: Failed to subscribe $topic');
+  }
+
+  void onUnsubscribed(String? topic) {
+    print('MQTT_LOGS:: Unsubscribed topic: $topic');
+  }
+
+  void pong() {
+    print('MQTT_LOGS:: Ping response client callback invoked');
+  }
+
+  void pumpTrigger(bool state) {
+    const pubTopic = 'trigger/pump';
+    final builder = MqttClientPayloadBuilder();
+    builder.addBool(val: state);
+    if (client.connectionStatus?.state == MqttConnectionState.connected) {
+      client.publishMessage(pubTopic, MqttQos.atMostOnce, builder.payload!);
+    }
+  }
+
+  void updateConfig(String nextRun, UnsignedInt duration, bool auto) {
+    const pubTopic = 'update/config';
+    final builder = MqttClientPayloadBuilder();
+    builder.addString(jsonEncode({
+      "next_run": nextRun,
+      "interval": duration,
+      "auto": auto,
+    }));
+    if (client.connectionStatus?.state == MqttConnectionState.connected) {
+      client.publishMessage(pubTopic, MqttQos.atMostOnce, builder.payload!);
+    }
+  }
+}

pubspec.lock

@@ -137,6 +137,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "2.1.0"
+  event_bus:
+    dependency: transitive
+    description:
+      name: event_bus
+      sha256: "44baa799834f4c803921873e7446a2add0f3efa45e101a054b1f0ab9b95f8edc"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.0.0"
   fake_async:
     dependency: transitive
     description:
@@ -432,6 +440,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.0.4"
+  mqtt_client:
+    dependency: "direct main"
+    description:
+      name: mqtt_client
+      sha256: "873c124f6485c17b5ca085047880068f3c5acc9db54317995d752a3253f95a72"
+      url: "https://pub.dev"
+    source: hosted
+    version: "10.0.0"
   nested:
     dependency: transitive
     description:

pubspec.yaml

@@ -23,6 +23,7 @@ dependencies:
   sliding_up_panel: ^2.0.0+1
   syncfusion_flutter_charts: ^23.1.44
   table_calendar: ^3.0.4
+  mqtt_client: ^10.0.0
 
 dev_dependencies:
   flutter_lints: ^3.0.1