#include <Wire.h> 
#include <LiquidCrystal_I2C.h>

// Define pins for LEDs
const int ledPin1 = 2;
const int ledPin2 = 4;
const int ledPin3 = 5;
const int ledPin4 = 18;

// Define pins for ultrasonic sensor
const int trigPin = 15; // Trigger pin
const int echoPin = 19; // Echo pin

// Define LCD properties
const int lcdColumns = 16;
const int lcdRows = 2;
LiquidCrystal_I2C lcd(0x27, lcdColumns, lcdRows);  // I2C address 0x27

void setup() {
  // Initialize serial communication
  Serial.begin(9600);

  // Initialize LED pins as outputs
  pinMode(ledPin1, OUTPUT);
  pinMode(ledPin2, OUTPUT);
  pinMode(ledPin3, OUTPUT);
  pinMode(ledPin4, OUTPUT);

  // Initialize ultrasonic sensor pins
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);

  // Initialize LCD
  lcd.init();
  lcd.backlight();
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Water Level:");
}

void loop() {
  // Trigger ultrasonic sensor
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  // Measure echo time
  long duration = pulseIn(echoPin, HIGH);

  // Calculate distance
  float distance = duration * 0.5 * 0.0343; // Distance in cm

  // Map distance to LED levels
  int level;
  if (distance < 50) {
    level = 0;
  } else if (distance < 100) {
    level = 1;
  } else if (distance < 200) {
    level = 2;
  } else if (distance < 300) {
    level = 3;
  } else {
    level = 4;
  }

  // Update LED indicators
  switch (level) {
    case 0:
      digitalWrite(ledPin1, HIGH);
      digitalWrite(ledPin2, HIGH);
      digitalWrite(ledPin3, HIGH);
      digitalWrite(ledPin4, HIGH);
      // Clear the LCD screen and display "TURN OFF PUMP"
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("TURN OFF PUMP");
      break;
    case 1:
      digitalWrite(ledPin1, LOW);
      digitalWrite(ledPin2, HIGH);
      digitalWrite(ledPin3, HIGH);
      digitalWrite(ledPin4, HIGH);
      break;
    case 2:
      digitalWrite(ledPin1, LOW);
      digitalWrite(ledPin2, LOW);
      digitalWrite(ledPin3, HIGH);
      digitalWrite(ledPin4, HIGH);
      break;
    case 3:
      digitalWrite(ledPin1, LOW);
      digitalWrite(ledPin2, LOW);
      digitalWrite(ledPin3, LOW);
      digitalWrite(ledPin4, HIGH);
      break;
    case 4:
      digitalWrite(ledPin1, LOW);
      digitalWrite(ledPin2, LOW);
      digitalWrite(ledPin3, LOW);
      digitalWrite(ledPin4, LOW);
      break;
  }

  // Update LCD display
  if (level != 0) {
    lcd.setCursor(0, 1);
    lcd.print("Level: ");
    lcd.print(level);
  }

  // Print distance and level to Serial Monitor
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.print(" cm, Level: ");
  Serial.println(level);

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