#include "DHT.h";
const int dht_pin = 9;
const int relay_fan_pin = 10;

DHT dht(dht_pin,DHT22);
bool isFanWorking = false;
const int TEMP_THRESHOLD = 20;
void setup() {
  Serial.begin(9600);
  dht.begin();
  pinMode(relay_fan_pin, OUTPUT);
}

void loop() {
  float temp_CS = dht.readTemperature();
  Serial.println(temp_CS);
  if(temp_CS > TEMP_THRESHOLD && isFanWorking == false){
    Serial.println("Fan is turned on!");
    digitalWrite(relay_fan_pin, HIGH);
    isFanWorking=true;
  }
  else if(temp_CS < TEMP_THRESHOLD && isFanWorking == true){
    Serial.println("Fan is turned Off!");
    digitalWrite(relay_fan_pin,LOW);
    isFanWorking = false;
  }
  delay(3000);
}

// #include <DHT.h>
// const int relay_fan_pin = 10;
// DHT dht(9,DHT22);

// bool isFanWorking = false;
// const int threshold = 20;
// unsigned long previous_millis = 0; 
// void setup(){
//   Serial.begin(9600);
//   dht.begin();
//   pinMode(relay_fan_pin,OUTPUT);
// }

// void loop(){
//   float temp = dht.readTemperature();
//   unsigned long current_millis = millis();

//   if(temp >= threshold && isFanWorking == false){
//     digitalWrite(relay_fan_pin,HIGH);
//     Serial.println("Fan Started Working!");
//     isFanWorking = true;
//     previous_millis = current_millis;
//   }
//   else if(temp < threshold && isFanWorking == true && current_millis - previous_millis > 5000){
//     digitalWrite(relay_fan_pin,LOW);
//     Serial.println("fan Stopped Working!");
//     isFanWorking = false;
//   }
// }