#define NUM_PARKING_SPOTS 4

// Pins for ultrasonic sensors
const int sensorPins[NUM_PARKING_SPOTS] = {2, 3, 4, 5}; // Example pins, adjust as needed

// Array to store parking spot statuses (0 for vacant, 1 for occupied)
int parkingStatus[NUM_PARKING_SPOTS] = {0};

void setup() {
  Serial.begin(9600);

  // Initialize sensor pins as inputs
  for (int i = 0; i < NUM_PARKING_SPOTS; i++) {
    pinMode(sensorPins[i], INPUT);
  }
}

void loop() {
  // Check each parking spot
  for (int i = 0; i < NUM_PARKING_SPOTS; i++) {
    int distance = readDistance(sensorPins[i]);

    // Check if parking spot is occupied
    if (distance < 20) { // Adjust threshold as needed
      if (parkingStatus[i] == 0) {
        parkingStatus[i] = 1;
      }
    } else {
      if (parkingStatus[i] == 1) {
        parkingStatus[i] = 0;
      }
    }
  }

  // Print parking status to Serial Monitor
  printParkingStatus();
  
  delay(1000); // Adjust delay as needed
}

// Function to read distance from ultrasonic sensor
int readDistance(int pin) {
  long duration;
  int distance;

  digitalWrite(pin, LOW);
  delayMicroseconds(2);
  digitalWrite(pin, HIGH);
  delayMicroseconds(10);
  digitalWrite(pin, LOW);
  duration = pulseIn(pin, HIGH);
  distance = duration * 0.034 / 2; // Speed of sound = 0.034 cm/microsecond
  return distance;
}

// Function to print parking status to Serial Monitor
void printParkingStatus() {
  Serial.println("Parking Status:");
  for (int i = 0; i < NUM_PARKING_SPOTS; i++) {
    Serial.print("Spot ");
    Serial.print(i + 1);
    Serial.print(": ");
    if (parkingStatus[i] == 0) {
      Serial.println("Vacant");
    } else {
      Serial.println("Occupied");
    }
  }
}