const int trigPin = 6;
const int echoPin = 7;

const int ledPins[] = {11, 12, 13, 14, 15, 16, 17, 18, 19, 20};
const int numLeds = sizeof(ledPins) / sizeof(ledPins[0]);

const int pumpPin = 4;
const int buttonPin = 3;

unsigned long previousMillis = 0;
const long pumpInterval = 30000; // 30 seconds
bool activatePump = false;

void setup() {
  Serial.begin(9600);
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);

  for (int i = 0; i < numLeds; i++) {
    pinMode(ledPins[i], OUTPUT);
  }

  pinMode(pumpPin, OUTPUT);
  pinMode(buttonPin, INPUT_PULLUP);
}

void loop() {
  unsigned long currentMillis = millis();

  // Check if the button is pushed
  if (digitalRead(buttonPin) == LOW) {
    activatePump = true;
    delay(50); // Debounce delay
  }

  // Ultrasonic sensor measurement
  long duration, distance;
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  duration = pulseIn(echoPin, HIGH);
  distance = duration / 58.2; // Convert to centimeters

  // Display water level on LED bar graph
  int ledsToLight = map(distance, 120, 2, 0, numLeds);
  for (int i = 0; i < numLeds; i++) {
    digitalWrite(ledPins[i], i < ledsToLight ? HIGH : LOW);
  }

  // Check pump conditions
  if (activatePump && (currentMillis - previousMillis >= pumpInterval || distance < 80)) {
    previousMillis = currentMillis;
    digitalWrite(pumpPin, HIGH); // Activate the pump
    activatePump = true;
  } else {
    digitalWrite(pumpPin, LOW); // Deactivate the pump
  }
}