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

// -------------------- CONFIG --------------------
#define DHT_PIN 15           
#define DHT_TYPE DHTesp::DHT22

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

const char* mqtt_server = "broker.hivemq.com";
const int mqtt_port = 1883;             // ✅ Correct port
const char* mqtt_topic = "tempdata";      // topic

// -------------------- GLOBALS --------------------
DHTesp dht;
WiFiClient espClient;
PubSubClient client(espClient);

// -------------------- FUNCTION DECLARATIONS --------------------
void connectWiFi();
void connectMQTT();
void publishSensorData();

// -------------------- SETUP --------------------
void setup() {
  Serial.begin(115200);
  dht.setup(DHT_PIN, DHT_TYPE);
  delay(2000);

  connectWiFi();
  client.setServer(mqtt_server, mqtt_port);
}

// -------------------- LOOP --------------------
void loop() {
  if (!client.connected()) {
    connectMQTT();
  }
  client.loop();

  publishSensorData();
  delay(2000);
}

// -------------------- CONNECT TO WIFI --------------------
void connectWiFi() {
  Serial.println("Connecting to WiFi...");
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("\nWiFi Connected!");
  Serial.print("IP Address: ");
  Serial.println(WiFi.localIP());
}

// -------------------- CONNECT TO MQTT --------------------
void connectMQTT() {
  while (!client.connected()) {

    String clientId = "ESP32_DHT22_" + WiFi.macAddress();
    clientId.replace(":", "");

    Serial.print("Connecting to MQTT with Client ID: ");
    Serial.println(clientId);

    if (client.connect(clientId.c_str())) {
      Serial.println("MQTT connected!");
    } else {
      Serial.print("MQTT connection failed, rc=");
      Serial.println(client.state());
      delay(2000);
    }
  }
}

// -------------------- READ SENSOR AND PUBLISH --------------------
void publishSensorData() {
  TempAndHumidity data = dht.getTempAndHumidity();
  
  if (!isnan(data.temperature) && !isnan(data.humidity)) {

    String payload = String("{\"temperature\":") + data.temperature +
                     ",\"humidity\":" + data.humidity + "}";

    client.publish(mqtt_topic, payload.c_str(), true);
    Serial.println("Published to lights: " + payload);

  } else {
    Serial.println("Failed to read from DHT22 sensor!");
  }
}