Lightswitch.ino

#include <ESP8266WiFi.h>
#include <Ticker.h>
#include <AsyncMqttClient.h>


#define WIFI_SSID "AndroidAP"
#define WIFI_PASSWORD "rnq20cck"

#define MQTT_HOST IPAddress(192, 168, 43, 224)
#define MQTT_PORT 1883

AsyncMqttClient mqttClient;
Ticker mqttReconnectTimer;

WiFiEventHandler wifiConnectHandler;
WiFiEventHandler wifiDisconnectHandler;
Ticker wifiReconnectTimer;

int button_pin = D0;
int LED_pin = D1;

void connectToWifi() {
  Serial.println("Connecting to Wi-Fi...");
  WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
}

void connectToMqtt() {
  Serial.println("Connecting to MQTT...");
  mqttClient.connect();
  mqttClient.setWill("system/status", 1, true, "ende");
}

void onWifiConnect(const WiFiEventStationModeGotIP& event) {
  Serial.println("Connected to Wi-Fi.");
  connectToMqtt();
}

void onWifiDisconnect(const WiFiEventStationModeDisconnected& event) {
  Serial.println("Disconnected from Wi-Fi.");
  mqttReconnectTimer.detach(); // ensure we don't reconnect to MQTT while reconnecting to Wi-Fi
  wifiReconnectTimer.once(2, connectToWifi);
}

void onMqttConnect(bool sessionPresent) {
  Serial.println("Connected to MQTT.");
  Serial.print("Session present: ");
  Serial.println(sessionPresent);
}

void onMqttDisconnect(AsyncMqttClientDisconnectReason reason) {
  Serial.println("Disconnected from MQTT.");

  if (WiFi.isConnected()) {
    mqttReconnectTimer.once(2, connectToMqtt);
  }
}

void setup() {
  Serial.begin(115200);
  Serial.println();

  wifiConnectHandler = WiFi.onStationModeGotIP(onWifiConnect);
  wifiDisconnectHandler = WiFi.onStationModeDisconnected(onWifiDisconnect);

  mqttClient.onConnect(onMqttConnect);
  mqttClient.onDisconnect(onMqttDisconnect);
  mqttClient.setServer(MQTT_HOST, MQTT_PORT);

  connectToWifi();

  pinMode(LED_pin, OUTPUT);
  pinMode(button_pin, INPUT);
}

void sendLightswitchStatus() {
  int switchStatus = digitalRead(button_pin); 
  digitalWrite(LED_pin, switchStatus); 
  
  uint16_t packetIdPub2 = mqttClient.publish("light_status", 1, true, String(switchStatus).c_str());
  Serial.println(packetIdPub2);
}

void loop() {  
  delay(1000);
  sendLightswitchStatus();
}