#define PIN_TRIG 3
#define PIN_ECHO 2
#define LED_MERAH 13   // Red LED for full trash
#define LED_HIJAU 12   // Green LED for not full

void setup() {
  Serial.begin(115200);  // Set baud rate for serial communication
  pinMode(PIN_TRIG, OUTPUT);
  pinMode(PIN_ECHO, INPUT);
  pinMode(LED_MERAH, OUTPUT);
  pinMode(LED_HIJAU, OUTPUT);
}

float getDistance() {
  // Trigger the ultrasonic sensor
  digitalWrite(PIN_TRIG, LOW);
  delayMicroseconds(2);
  digitalWrite(PIN_TRIG, HIGH);
  delayMicroseconds(10);
  digitalWrite(PIN_TRIG, LOW);

  // Measure the echo time
  int echoDuration = pulseIn(PIN_ECHO, HIGH);
  
  // Calculate distance in cm
  return echoDuration * 0.034 / 2;
}

void loop() {
  float distance = getDistance();
  Serial.println(distance);  // To debug and see the measured distance

  // Condition to check if trash is 53 cm or less (turn red LED on)
  if (distance <= 53) {  // Trash level is at or below 53 cm
    digitalWrite(LED_MERAH, HIGH);   // Turn on red LED (trash is full)
    digitalWrite(LED_HIJAU, LOW);    // Turn off green LED
  } 
  else if (distance > 53 && distance <= 400) {  // Trash level is above 53 cm
    digitalWrite(LED_MERAH, LOW);    // Turn off red LED
    digitalWrite(LED_HIJAU, HIGH);   // Turn on green LED (trash is not full)
  } else {
    // If the distance is beyond sensor range, turn off both LEDs as an error indication
    digitalWrite(LED_MERAH, LOW);
    digitalWrite(LED_HIJAU, LOW);
  }

  delay(500);  // Short delay for sensor reading
}