#include <WiFi.h>
#include <PubSubClient.h>

const char* ssid = "Wokwi-GUEST";
const char* password = "";
const char* mqtt_server = "test.mosquitto.org";

WiFiClient espClient;
PubSubClient client(espClient);

const int ledPins[] = {16, 4, 5};  // GPIO pins for the LEDs

void setup_wifi() {
  delay(10);
  Serial.println();
  Serial.print("Connecting to ");
  Serial.println(ssid);

  WiFi.mode(WIFI_STA); // Set WiFi mode to station
  WiFi.begin(ssid, password); // Connect to WiFi

  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }

  Serial.println("");
  Serial.println("WiFi connected");
  Serial.println("IP address: ");
  Serial.println(WiFi.localIP());
}

void callback(char* topic, byte* message, unsigned int length) {
  String messageTemp;
  for (int i = 0; i < length; i++) {
    messageTemp += (char)message[i];
  }

  Serial.print("Message arrived in topic: ");
  Serial.println(topic);
  Serial.print("Message:");
  for (int i = 0; i < length; i++) {
    Serial.print((char)message[i]);
  }
  Serial.println();
  Serial.println("-----------------------");

  if (String(topic) == "dtstelco20/esp32/led1") {
    Serial.print("Handling esp32/led1 with message: ");
    Serial.println(messageTemp);
         Serial.println("OK");
      if(messageTemp=="on"){
        //Serial.println("Led ON");
        digitalWrite(16,HIGH);
        Serial.print("Set GPIO 16 to state: HIGH");
        Serial.print('\n');
      }  
      else{
        digitalWrite(16,LOW);
        Serial.print("Set GPIO 16 to state: LOW");
        Serial.print('\n');
      }

  } else if (String(topic) == "dtstelco20/esp32/led2") {
    Serial.print("Handling esp32/led2 with message: ");
    Serial.println(messageTemp);
        Serial.println("OK");
      if(messageTemp=="on"){
        //Serial.println("Led ON");
        digitalWrite(4,HIGH);
        Serial.print("Set GPIO 4 to state: HIGH");
        Serial.print('\n');
      }  
      else{
        digitalWrite(4,LOW);
        Serial.print("Set GPIO 4 to state: LOW");
        Serial.print('\n');
      }

  } else if (String(topic) == "dtstelco20/esp32/led3") {
    Serial.print("Handling esp32/led3 with message: ");
    Serial.println(messageTemp);
             Serial.println("OK");
      if(messageTemp=="on"){
        //Serial.println("Led ON");
        digitalWrite(5,HIGH);
        Serial.print("Set GPIO 5 to state: HIGH");
        Serial.print('\n');
      }  
      else{
        digitalWrite(5,LOW);
        Serial.print("Set GPIO 5 to state: LOW");
        Serial.print('\n');
      }

  }
  
  // Publish acknowledgment message
  client.publish("dtstelco20/esp32/feedback", "Hi, I'm ESP32 ^^");
}

void reconnect() {
  while (!client.connected()) {
    Serial.print("Attempting MQTT connection...");
    String clientId = "ESP32Client-";
    clientId += String(random(0xffff), HEX);
    if (client.connect(clientId.c_str())) {
      Serial.println("connected");
      client.subscribe("dtstelco20/esp32/led1");
      client.subscribe("dtstelco20/esp32/led2");
      client.subscribe("dtstelco20/esp32/led3");
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      delay(5000);
    }
  }
}

void setup() {
  for (int i = 0; i < 3; i++) {
    pinMode(ledPins[i], OUTPUT);
  }
  Serial.begin(115200);
  setup_wifi();
  client.setServer(mqtt_server, 1883);
  client.setCallback(callback);
}

void loop() {
  if (!client.connected()) {
    reconnect();
  }
  client.loop();
}