#include <Arduino.h>
#include <WiFi.h>
#include <Wire.h>
#include <PubSubClient.h>
#include <Adafruit_Sensor.h>
#include <DHT.h>

#define DHTPIN 16
#define DHTTYPE DHT22
DHT dht(DHTPIN, DHT22);
WiFiClient wifiClient;
PubSubClient mqttClient(wifiClient);

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

// Use public MQTT broker for testing
const char* mqttServer = "broker.hivemq.com";
int mqttPort = 1883;  // Typically, non-SSL/TLS port

int period = 600;
unsigned long time_now = 0;

void setupMQTT() {
  mqttClient.setServer(mqttServer, mqttPort);
  mqttClient.setCallback(callback);
}

void reconnect() {
  Serial.println("Connecting to MQTT Broker...");
  while (!mqttClient.connected()) {
    Serial.print("Reconnecting to MQTT Broker...");
    String clientId = "ESP32Client-";
    clientId += String(random(0xffff), HEX);

    if (mqttClient.connect(clientId.c_str())) {
      Serial.println("Connected.");
      // subscribe to topic
      mqttClient.subscribe("esp32/msg");
    } else {
      Serial.print("Failed to connect. State: ");
      Serial.println(mqttClient.state());
      delay(2000);
    }
  }
}

void setup() {
  Serial.begin(115200);
  pinMode(16, OUTPUT);
  dht.begin();

  WiFi.begin(ssid, pass);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.println("Connected to Wi-Fi");

  setupMQTT();
}

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

  if (millis() >= time_now + period) {
    time_now += period;
    float temperature = dht.readTemperature();
    char tempString[8];
    dtostrf(temperature, 1, 2, tempString);
    Serial.print("Temperature: ");
    Serial.println(tempString);
    mqttClient.publish("esp32/temperature", tempString);

    float humidity = dht.readHumidity();
    char humString[8];
    dtostrf(humidity, 1, 2, humString);
    Serial.print("Humidity: ");
    Serial.println(humString);
    mqttClient.publish("esp32/humidity", humString);

    // Publish a combined message to esp32/sub
    String combinedData = "Temperature: " + String(temperature) + ", Humidity: " + String(humidity);
    mqttClient.publish("esp32/sub", combinedData.c_str());
  }
}

void callback(char* topic, byte* message, unsigned int length) {
  Serial.print("Message arrived ");
  Serial.print(topic);
  Serial.print(": ");
  String data = "";
  for (int i = 0; i < length; i++) {
    Serial.print((char)message[i]);
    data += (char)message[i];
  }
  Serial.println();
}