Refactored code and added support for kasa smart plugs

mqtt/mqtt.go

@@ -0,0 +1,109 @@
+package mqtt
+
+import (
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+
+	"github.com/eclipse/paho.mqtt.golang"
+)
+
+type MQTT struct {
+	Presence chan bool
+	client   mqtt.Client
+}
+
+// This is the default message handler, it just prints out the topic and message
+var defaultHandler mqtt.MessageHandler = func(client mqtt.Client, msg mqtt.Message) {
+	fmt.Printf("TOPIC: %s\n", msg.Topic())
+	fmt.Printf("MSG: %s\n", msg.Payload())
+}
+
+// Handler got automation/presence/+
+func presenceHandler(presence chan bool) func(mqtt.Client, mqtt.Message) {
+	devices := make(map[string]bool)
+	var current *bool
+
+	return func(client mqtt.Client, msg mqtt.Message) {
+		name := strings.Split(msg.Topic(), "/")[2]
+		if len(msg.Payload()) == 0 {
+			// @TODO What happens if we delete a device that does not exist
+			delete(devices, name)
+		} else {
+			value, err := strconv.Atoi(string(msg.Payload()))
+			if err != nil {
+				panic(err)
+			}
+
+			devices[name] = value == 1
+		}
+
+		present := false
+		fmt.Println(devices)
+		for _, value := range devices {
+			if value {
+				present = true
+				break
+			}
+		}
+
+		if current == nil || *current != present {
+			current = &present
+			presence <- present
+		}
+
+	}
+}
+
+func Connect() MQTT {
+	host, ok := os.LookupEnv("MQTT_HOST")
+	if !ok {
+		host = "localhost"
+	}
+	port, ok := os.LookupEnv("MQTT_PORT")
+	if !ok {
+		port = "1883"
+	}
+	user, ok := os.LookupEnv("MQTT_USER")
+	if !ok {
+		user = "test"
+	}
+	pass, ok := os.LookupEnv("MQTT_PASS")
+	if !ok {
+		pass = "test"
+	}
+	clientID, ok := os.LookupEnv("MQTT_CLIENT_ID")
+	if !ok {
+		clientID = "automation"
+	}
+
+	opts := mqtt.NewClientOptions().AddBroker(fmt.Sprintf("%s:%s", host, port))
+	opts.SetClientID(clientID)
+	opts.SetDefaultPublishHandler(defaultHandler)
+	opts.SetUsername(user)
+	opts.SetPassword(pass)
+
+	client := mqtt.NewClient(opts)
+	if token := client.Connect(); token.Wait() && token.Error() != nil {
+		panic(token.Error())
+	}
+
+	m := MQTT{client: client, Presence: make(chan bool)}
+
+	if token := client.Subscribe("automation/presence/+", 0, presenceHandler(m.Presence)); token.Wait() && token.Error() != nil {
+		fmt.Println(token.Error())
+		os.Exit(1)
+	}
+
+	return m
+}
+
+func (m *MQTT) Disconnect() {
+	if token := m.client.Unsubscribe("automation/presence/+"); token.Wait() && token.Error() != nil {
+		fmt.Println(token.Error())
+		os.Exit(1)
+	}
+
+	m.client.Disconnect(250)
+}