#include <DHT.h>

#define TRIG_PIN  16  // Pin connected to the Trig of the HC-SR04
#define ECHO_PIN  4  // Pin connected to the Echo of the HC-SR04
#define DHT_PIN   18  // Pin connected to the DHT22
#define LED1_PIN  27  // Pin connected to LED 1
#define YELLOW_LED_PIN  26  // Pin connected to Yellow LED
#define BLUE_LED_PIN  25  // Pin connected to Blue LED
#define DHTTYPE DHT22

DHT dht(DHT_PIN, DHTTYPE);  // Initialize DHT sensor

void setup() {
  Serial.begin(115200);
  
  pinMode(LED1_PIN, OUTPUT);
  pinMode(YELLOW_LED_PIN, OUTPUT);
  pinMode(BLUE_LED_PIN, OUTPUT);
  
  dht.begin();
}

void loop() {
  // Measure distance
  long duration, distance;
  digitalWrite(TRIG_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);
  duration = pulseIn(ECHO_PIN, HIGH);
  distance = duration * 0.034 / 2; // Convert to cm
  
  // Measure temperature
  float temperature = dht.readTemperature(); // Read temperature in Celsius
  
  // Control LED1 based on distance
  if (distance <= 100) {
    digitalWrite(LED1_PIN, HIGH);
    delay(500);  // On for half a second
    digitalWrite(LED1_PIN, LOW);
    delay(500);  // Off for half a second
  } else {
    digitalWrite(LED1_PIN, HIGH); // On when distance > 100 cm
  }

  // Control Yellow LED based on temperature
  if (temperature > 50) {
    digitalWrite(YELLOW_LED_PIN, HIGH); // On when temperature > 50°C
  } else {
    digitalWrite(YELLOW_LED_PIN, LOW); // Off otherwise
  }

  // Control Blue LED based on temperature
  if (temperature < 0) {
    digitalWrite(BLUE_LED_PIN, HIGH); // On when temperature < 0°C
  } else {
    digitalWrite(BLUE_LED_PIN, LOW); // Off otherwise
  }
  
  // Print values to Serial Monitor for debugging
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.print(" cm, Temperature: ");
  Serial.print(temperature);
  Serial.println(" °C");
  
  delay(1000); // Wait a second before next measurement
}