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

#define RED_PIN 27
#define GREEN_PIN 26
#define BLUE_BUZZER_PIN 25

const char* ssid = "Wokwi-GUEST";
const char* password = "";
WiFiClient wifiClient;

const char* mqttServer = "broker.hivemq.com";
const int mqttPort = 1883;
const char* mqttUser = "";
const char* mqttPassword = "";
const char* topic_led1 = "ITKPS/Lab/T6621604823/led1";
const char* topic_led2 = "ITKPS/Lab/T6621604823/led2";
const char* topic_buzzer = "ITKPS/Lab/T6621604823/buzzer";
PubSubClient mqttClient(wifiClient);

void setup_wifi() {
  Serial.println();
  Serial.print("Connecting to ");
  Serial.println(ssid);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println();
  Serial.print("WiFi connected on ");
  Serial.print("IP address: ");
  Serial.print(WiFi.localIP());
  Serial.print(" MAC address: ");
  Serial.println(WiFi.macAddress());
}

void reconnectMQTT() {
  char mqttinfo[80];
  char clientId[100] = "\0";
  snprintf (mqttinfo, 75, "Attempting MQTT connection at %s:%d ( %s / %s)...", mqttServer, mqttPort, mqttUser, mqttPassword);
  while (!mqttClient.connected()) {
  Serial.println(mqttinfo);
    sprintf(clientId, "ESP32Client-%04X", random(0xffff));
    if (mqttClient.connect(clientId)) {
      Serial.println("...MQTT Broker connected...");
      mqttClient.subscribe(topic_led1);
      mqttClient.subscribe(topic_led2);
      mqttClient.subscribe(topic_buzzer);
    } else {
      Serial.print("failed, rc=");
      Serial.print(mqttClient.state());
      Serial.println(" try again in 5 seconds");
      delay(5000);
    }
  }
}

void mqttCallback(char* topic, byte* payload, unsigned int length) {
  char payloadMsg[128];
  Serial.print("Message arrived in topic: ");
  Serial.print(topic);
  Serial.print(" Message:");
  for (int i = 0; i < length; i++) {
    Serial.print((char)payload[i]);
    payloadMsg[i] = (char) payload[i];
  }
  payloadMsg[length] = '\0';
  Serial.println();
  Serial.println("-----------------------");
  String message = String(payloadMsg);
  

    if (String(topic) == topic_led1) {
    if (message == "1") {
      digitalWrite(RED_PIN, LOW);
    } else {
      digitalWrite(RED_PIN, HIGH);
    }
  }
  else if (String(topic) == topic_led2) {
    if (message == "1") {
      digitalWrite(GREEN_PIN, LOW);
    } else {
      digitalWrite(GREEN_PIN, HIGH);
    }
  }
  else if (String(topic) == topic_buzzer) {
    if (message == "1") {
      digitalWrite(BLUE_BUZZER_PIN, LOW);
    } else {
      digitalWrite(BLUE_BUZZER_PIN, HIGH);
    }
  }
}

void setup() {
  Serial.begin(115200);
  pinMode(RED_PIN, OUTPUT);
  pinMode(GREEN_PIN, OUTPUT);
  pinMode(BLUE_BUZZER_PIN, OUTPUT);

  digitalWrite(RED_PIN, LOW);
  digitalWrite(GREEN_PIN, LOW);
  digitalWrite(BLUE_BUZZER_PIN, LOW);
  setup_wifi();
  mqttClient.setServer(mqttServer, mqttPort);
  mqttClient.setCallback(mqttCallback); 
}
void loop() {
  if (!mqttClient.connected()) {
    reconnectMQTT();
  }
  mqttClient.loop();

  delay(50);
}