#include <DHT.h>

#define DHT_PIN 4
#define DHT_TYPE DHT11

#define LED_PIN 5
#define BUZZER_PIN 18

DHT dht(DHT_PIN, DHT_TYPE);

void setup() {
  Serial.begin(115200);

  dht.begin();

  pinMode(LED_PIN, OUTPUT);
  pinMode(BUZZER_PIN, OUTPUT);

  digitalWrite(LED_PIN, LOW);
  digitalWrite(BUZZER_PIN, LOW);

  Serial.println("DHT11 Temperature Monitoring System");
}

void loop() {

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

  if (isnan(temperature) || isnan(humidity)) {
    Serial.println("Failed to read DHT11!");
    delay(2000);
    return;
  }

  Serial.print("Temperature: ");
  Serial.print(temperature);
  Serial.print(" °C | Humidity: ");
  Serial.print(humidity);
  Serial.println(" %");

  // Temperature alert
  if (temperature >= 30.0) {
    digitalWrite(LED_PIN, HIGH);
    digitalWrite(BUZZER_PIN, HIGH);

    Serial.println("⚠ HIGH TEMPERATURE!");
  } 
  else {
    digitalWrite(LED_PIN, LOW);
    digitalWrite(BUZZER_PIN, LOW);

    Serial.println("Temperature Normal");
  }

  delay(2000);
}