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

const char* ssid = "Wokwi-GUEST";
const char* password = "";
const char* mqttServer = "broker.emqx.io";
int port = 1883;
char clientId[50];
unsigned long lastMsg = 0;
#define MSG_BUFFER_SIZE	(50)
char msg[MSG_BUFFER_SIZE];
int value = 0;

WiFiClient espClient;
PubSubClient client(espClient);

const int ledPin = 2;

#define ADC_VREF_mV    5000.0 // in millivolt
#define ADC_RESOLUTION 4096.0
#define PIN_LM35       34

// Function to calculate x based on the algorithm
float calculateX() {
  // Replace with your NIM, Tanggal Lahir, Bulan Lahir, and 2 Digit Tahun Lahir
  int nimLastTwoDigits = 8;
  int tanggalLahir = 9;
  int bulanLahir = 9;
  int tahunLahirLastTwoDigits = 4;

  float x = (nimLastTwoDigits + tanggalLahir + bulanLahir + tahunLahirLastTwoDigits) * 0.015;
  return x;
}

void setup() {
  Serial.begin(9600);
  randomSeed(analogRead(0));

  delay(10);
  Serial.println();
  Serial.print("Connecting to ");
  Serial.println(ssid);

  wifiConnect();

  Serial.println("");
  Serial.println("WiFi connected");
  Serial.println("IP address: ");
  Serial.println(WiFi.localIP());

  client.setServer(mqttServer, port);
  client.setCallback(callback);
  pinMode(ledPin, OUTPUT);
}

void wifiConnect() {
  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
}

void mqttReconnect() {
  while (!client.connected()) {
    Serial.print("Attempting MQTT connection...");
    long r = random(1000);
    sprintf(clientId, "clientId-%ld", r);
    if (client.connect(clientId)) {
      Serial.print(clientId);
      Serial.println(" connected");
      client.subscribe("inTopic2A");
    } else {
      Serial.print("failed, rc=");
      Serial.print(client.state());
      Serial.println(" try again in 5 seconds");
      delay(5000);
    }
  }
}

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

  for (int i = 0; i < length; i++) {
    Serial.print((char)message[i]);
    stMessage += (char)message[i];
  }
  Serial.println();

  if (String(topic) == "inTopic2A") {
    Serial.print("Changing output to ");
    if (stMessage == "1") {
      Serial.println("on");
      digitalWrite(ledPin, HIGH);
    } else if (stMessage == "0") {
      Serial.println("off");
      digitalWrite(ledPin, LOW);
    }
  }
}

void loop() {
  // get the ADC value from the temperature sensor
  int adcVal = analogRead(PIN_LM35);
  // convert the ADC value to voltage in millivolt
  float milliVolt = adcVal * (ADC_VREF_mV / ADC_RESOLUTION);
  // convert the voltage to the temperature in Celsius
  float tempC = milliVolt / 10;

  float x = calculateX();

  // print the temperature in the Serial Monitor:
  // Serial.print("Temperature: ");
  // Serial.print(tempC);   // print the temperature in Celsius
  // Serial.println("°C");

  if (!client.connected()) {
    mqttReconnect();
  }
  client.loop();
  unsigned long now = millis();
  if (now - lastMsg > 2000) {
    lastMsg = now;
    //++value;
    // print the temperature in the Serial Monitor:
    Serial.print("Temperature: ");
    Serial.print(tempC);   // print the temperature in Celsius
    Serial.println("°C");

    // Check temperature range and publish corresponding message
    if (tempC < 27 * x) {
      snprintf(msg, MSG_BUFFER_SIZE, "Dingin");
    } else if (tempC >= 27 * x && tempC <= 30 * x) {
      snprintf(msg, MSG_BUFFER_SIZE, "Hangat");
    } else {
      snprintf(msg, MSG_BUFFER_SIZE, "Panas");
    }

    Serial.print("Publish message: ");
    Serial.println(msg);
    client.publish("outTopic2A", msg);
  }
}