const int trigPins[] = {13,11,9,7};  // Trig pins for ultrasonic sensors
const int echoPins[] = {12,10,8,6};  // Echo pins for ultrasonic sensors
const int ledPins[] = {2,3,4,5};  // LED pins
const int proximityThreshold = 100;  // Distance in centimeters
const int detectionTime = 5000;  // Time in milliseconds (5 seconds)


bool sensors[] = {false, false, false, false};
void setup() {
  Serial.begin(9600);
  
  for (int i = 0; i < 4; i++) {
    pinMode(trigPins[i], OUTPUT);
    pinMode(echoPins[i], INPUT);
    pinMode(ledPins[i], OUTPUT);
  }
}

void loop() {
  int detectionCount = 0;
  unsigned long startTime = 0;
          digitalWrite(ledPins[2], HIGH); // Turn on LED

  while (detectionCount < 4) {
    for (int i = 0; i < 4; i++) {
      // Trigger the ultrasonic sensor
      digitalWrite(trigPins[i], LOW);
      delayMicroseconds(2);
      digitalWrite(trigPins[i], HIGH);
      delayMicroseconds(10);
      digitalWrite(trigPins[i], LOW);

      // Read the echo duration in microseconds
      long duration = pulseIn(echoPins[i], HIGH);

      // Convert the duration to centimeters
      int distance = duration * 0.034 / 2;

      // Serial.print("Sensor ");
      // Serial.print(i + 1);
      // Serial.print(" Distance: ");
      // Serial.println(distance);

      if (distance < proximityThreshold) {
        sensors[i] = true;
      }
      else
      {
        sensors[i] = false;
      }
    }
    if (millis() - startTime >= detectionTime && sensors[0] == true && sensors[1] == true && sensors[2] == true && sensors[3] == true ){
      // All sensors detected an object closer than 10cm for 5 seconds
      // HERE YOU CAN TURN ON LEDS BASED ON WHICH SENSOR IS true or false
        digitalWrite(ledPins[0], HIGH); // Turn on LED 1
        digitalWrite(ledPins[1], HIGH); // Turn on LED 2
        digitalWrite(ledPins[2], HIGH); // Turn on LED 3
        digitalWrite(ledPins[3], HIGH); // Turn on LED 4
        delay(1000); 
        digitalWrite(ledPins[0], LOW);
        digitalWrite(ledPins[1], LOW); 
        digitalWrite(ledPins[2], LOW); 
        digitalWrite(ledPins[3], LOW);
      }

    else if (millis() - startTime >= detectionTime && ((sensors[0] == true && sensors[1] == true && sensors[2] == true) || (sensors[0] == true && sensors[1] == true && sensors[3] == true) || (sensors[0] == true && sensors[2] == true && sensors[3] == true) || (sensors[1] == true && sensors[2] == true && sensors[3] == true))){
      // All sensors detected an object closer than 10cm for 5 seconds
      // HERE YOU CAN TURN ON LEDS BASED ON WHICH SENSOR IS true or false
        digitalWrite(ledPins[0], HIGH); // Turn on LED 1
        digitalWrite(ledPins[1], HIGH); // Turn on LED 2
        digitalWrite(ledPins[2], HIGH); // Turn on LED 3
        delay(1000); 
        digitalWrite(ledPins[0], LOW);
        digitalWrite(ledPins[1], LOW); 
        digitalWrite(ledPins[2], LOW); 
      }

    else if (millis() - startTime >= detectionTime && ((sensors[0] == true && sensors[1] == true )|| (sensors[0] == true && sensors[2] == true)||(sensors[0] == true && sensors[3] == true) || (sensors[1] == true && sensors[2] == true) || (sensors[1] == true && sensors[3] == true) || (sensors[2] == true && sensors[3] == true))){
      // All sensors detected an object closer than 10cm for 5 seconds
      // HERE YOU CAN TURN ON LEDS BASED ON WHICH SENSOR IS true or false
        digitalWrite(ledPins[0], HIGH); // Turn on LED 1
        digitalWrite(ledPins[1], HIGH); // Turn on LED 2
        delay(1000); 
        digitalWrite(ledPins[0], LOW);
        digitalWrite(ledPins[1], LOW); 
      }

    else if (millis() - startTime >= detectionTime && ((sensors[0] == true) || (sensors[1] == true) || (sensors[2] == true) || (sensors[3] == true))){
      // All sensors detected an object closer than 10cm for 5 seconds
      // HERE YOU CAN TURN ON LEDS BASED ON WHICH SENSOR IS true or false
        digitalWrite(ledPins[0], HIGH); // Turn on LED 1
        delay(1000); 
        digitalWrite(ledPins[0], LOW); // Turn on LED 1
      }
   
   
    
    else {
      // Reset LEDs
      for (int i = 2; i < 6; i++) {
                // Serial.print("no");

        digitalWrite(ledPins[i], LOW); // Turn off LED
      }
    }
  }

  delay(1000); // Adjust the delay as needed
}