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

// Replace with your network credentials
const char* ssid = "Wokwi-GUEST";
const char* password = "";

// HiveMQ public broker settings
const char* mqtt_server = "broker.hivemq.com";
const int mqtt_port = 1883;
const char* mqtt_topic = "testdht"; // Topic for DHT sensor readings
const char* mqtt_led_topic = "testled"; // Topic for controlling LED

// DHT Sensor
#define DHTPIN 4 // Define the GPIO pin connected to the DHT11 data pin
#define DHTTYPE DHT22
DHT dht(DHTPIN, DHTTYPE);

// LED Pin
const int LEDPIN = 2; // Define the GPIO pin connected to the LED

// WiFi and MQTT clients
WiFiClient wifiClient;
PubSubClient client(wifiClient);

void setup_wifi() {
  delay(10);
  Serial.begin(115200);
  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.println("WiFi connected");
  Serial.println("IP address: ");
  Serial.println(WiFi.localIP());
}

void callback(char* topic, byte* message, unsigned int length) {
  Serial.print("Message arrived in topic: ");
  Serial.println(topic);

  // Convert message to String
  String msg = "";
  for (int i = 0; i < length; i++) {
    msg += (char)message[i];
  }

  // Check if message is "on" or "off" to control LED
  if (String(topic) == mqtt_led_topic) {
    if (msg == "on") {
      digitalWrite(LEDPIN, HIGH); // Turn on LED
      Serial.println("LED turned on");
    } else if (msg == "off") {
      digitalWrite(LEDPIN, LOW); // Turn off LED
      Serial.println("LED turned off");
    }
  }
}

void reconnect() {
  while (!client.connected()) {
    Serial.print("Attempting MQTT connection...");
    if (client.connect("ESP32Client")) {
      Serial.println("connected");
      client.subscribe(mqtt_led_topic); // Subscribe to LED control topic
      client.publish(mqtt_topic, "ESP32 connected");
    } else {
      setup_wifi();
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      delay(5000);
    }
  }
}

void setup() {
  pinMode(LEDPIN, OUTPUT); // Initialize LED pin
  digitalWrite(LEDPIN, LOW); // Ensure LED is initially off

  dht.begin();
  setup_wifi();
  client.setServer(mqtt_server, mqtt_port);
  client.setCallback(callback);
}

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

  // Your code to read sensor data and construct the payload
  float temperature = 25.0;
  float humidity = 50.0;
  String payload = "T: " + String(temperature) + " °C, H: " + String(humidity) + " %";
  Serial.println(payload);

  // Publish the message to the MQTT broker
  client.publish(mqtt_topic, payload.c_str());
 // Adjust as needed
}