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

#define DHTPIN  14
#define DHTTYPE DHT22

#define WIFI_SSID "Wokwi-GUEST"
#define WIFI_PASSWORD ""
#define WIFI_CHANNEL 6

#define MSG_BUFFER_SIZE  (50)

const char *MQTT_SERVER = "test.mosquitto.org"; 
const uint16_t MQTT_PORT = 1883;
const char *MQTT_CLIENT_NAME = "AIUIOT_Test"; 
// Add your name in the middle to create a unique folder
const char *MQTT_TOPIC_1 = "arif/humidity";
const char *MQTT_TOPIC_2 = "arif/temperature";

float temperature = 0;
float humidity = 0;
unsigned long lastMsg = 0;

DHT dht(DHTPIN, DHTTYPE);
WiFiClient espClient; 
PubSubClient mqttClient(espClient); 

void ConnectWiFi() 
{
  WiFi.begin(WIFI_SSID, WIFI_PASSWORD, WIFI_CHANNEL);
  Serial.print("Connecting to WiFi ");
  Serial.print(WIFI_SSID);
  while (WiFi.status() != WL_CONNECTED)
  {
    delay(500);
    Serial.print(".");
  }
  Serial.println("WiFi Connected!");
  Serial.print("IP address: ");
  Serial.println(WiFi.localIP());
}

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

  if ((char)payload[0] == '1') {
    digitalWrite(2, LOW);
  } else {
    digitalWrite(2, HIGH);
  }
}

void InitMqtt() 
{
  mqttClient.setServer(MQTT_SERVER, MQTT_PORT);
  mqttClient.setCallback(Callback);
}

void ConnectMqtt() 
{
  while (!mqttClient.connected())
  {
    Serial.print("Attempting MQTT connection...");
    String clientId = "ESP32Client-";
    clientId += MQTT_CLIENT_NAME;
    if (mqttClient.connect((clientId).c_str()))
    {
      Serial.println("Client connected!");
      mqttClient.publish("aiuiot/mqtt", "aiuiot");
      mqttClient.subscribe("aiuiot/mqtt");
    }
    else
    {
      Serial.print("Failed MQTT connection, rc=");
      Serial.print(mqttClient.state());
      Serial.println("try again in 5 seconds");
      delay(5000);
    }
  }
}

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

void setup(void)
{
  pinMode(2, OUTPUT);
  Serial.println(F("MQTT with DH22 Test!"));
  Serial.begin(115200);
  ConnectWiFi();
  InitMqtt();
  dht.begin();
}

void loop()
{
  HandleMqtt();

  unsigned long now = millis();
  if (now - lastMsg > 2000) {
    lastMsg = now;

    float humidity = dht.readHumidity();
    float temperature = dht.readTemperature();

    if (isnan(humidity) || isnan(temperature)) {
      Serial.println(F("Failed to read from DHT sensor!"));
      return;
    }

    Serial.println();
    Serial.print("Humidity: ");
    Serial.print(humidity);
    mqttClient.publish(MQTT_TOPIC_1, String(humidity).c_str());
    Serial.print(" -> Published humidity: ");
    Serial.print(String(humidity).c_str());
    Serial.println();
    Serial.print("Temperature: ");
    Serial.print(temperature);
    Serial.print(" °C ");
    mqttClient.publish(MQTT_TOPIC_2, String(temperature).c_str());
    Serial.print(" -> Published temperature: ");
    Serial.print(String(temperature).c_str());
    Serial.print(" °C ");
    Serial.println();
    delay(3000);
  }
}