#include <WiFi.h>
#include <ThingsBoard.h>
#include <Arduino_MQTT_Client.h>

#define BAUD_RATE 115200
#define NTC_TEMP_PIN A0
#define ADC_MAX 4095.0
#define CELSIUS_TO_KELVIN 273.15

// ThingsBoard
#define TB_SERVER "thingsboard.cloud"
#define TOKEN "hyBwTmT6AyCS1GmhFXvF"
constexpr uint16_t MAX_MESSAGE_SIZE = 256U;

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

WiFiClient espClient;
Arduino_MQTT_Client mqttClient(espClient);
ThingsBoard tb(mqttClient, MAX_MESSAGE_SIZE);

const float BETA = 3950;
const float MIN_VALUE = 298.15;

int getTemp(int analogValue) {
  float celsius = 1 / (log(1 / (ADC_MAX / analogValue - 1)) / BETA + 1.0 / MIN_VALUE) - CELSIUS_TO_KELVIN;
  return celsius;
}

void setup() {
  Serial.begin(BAUD_RATE);
  pinMode(NTC_TEMP_PIN, INPUT);
  
  // Connecting to a Wi-Fi network
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.println("Connecting to WiFi..");
  }
  Serial.println("Connected to the Wi-Fi network");
  // Connecting to ThingsBoard
  connectToThingsBoard();
}

void connectToThingsBoard() {
  if (!tb.connected()) {
    Serial.println("Connecting to ThingsBoard server");
    if (!tb.connect(TB_SERVER, TOKEN)) {
      Serial.println("Failed to connect to ThingsBoard");
    } else {
      Serial.println("Connected to ThingsBoard");
    }
  }
}

void sendDataToThingsBoard(float temp) {
  String jsonData = "{\"tempIn\":" + String(temp) + "}";
  tb.sendTelemetryJson(jsonData.c_str());
  Serial.println("Data sent to ThingsBoard");
}

void loop() {
  // Convert voltage to temp
  int NTC_Raw = analogRead(NTC_TEMP_PIN);
  int NTC_Temp = getTemp(NTC_Raw);
  Serial.print("Temperature: ");
  Serial.print(NTC_Temp);
  Serial.println();

  if (!tb.connected()) {
    connectToThingsBoard();
  }

  sendDataToThingsBoard(NTC_Temp);

  tb.loop();
  delay(1500);
}