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

// Set up the LCD with I2C address 0x27 and a 16x2 display
LiquidCrystal_I2C lcd(0x27, 16, 2);

// Pin Definitions
const int tankFullPin = 7;  // Pin for tank full sensor
const int tankEmptyPin = 6; // Pin for tank empty sensor
const int pumpPin = 13;     // Pin for pump control
const int buttonPin = 2;    // Pin for manual button (optional for pump control)

void setup() {
  lcd.begin(16, 2);   // Initialize the LCD
  lcd.backlight();    // Turn on the LCD backlight

  // Set the sensor pins as input
  pinMode(tankFullPin, INPUT);
  pinMode(tankEmptyPin, INPUT);
  pinMode(pumpPin, OUTPUT);

  // Set up the button pin as input
  pinMode(buttonPin, INPUT_PULLUP); // Using internal pull-up resistor

  // Start serial communication for manual input via Serial Monitor
  Serial.begin(9600);

  // Display initial message on the LCD
  lcd.print("  Hello");
  delay(100);  // Short delay to show the initial message
}

void loop() {
  // Read the tank sensor states
  int tankFull = digitalRead(tankFullPin);
  int tankEmpty = digitalRead(tankEmptyPin);

  // Check if Serial input is available (manual control via Serial Monitor)
  if (Serial.available() > 0) {
    char input = Serial.read();
    if (input == 'f') { // 'f' for tank full
      lcd.clear();
      lcd.print("  Tank is full");
      digitalWrite(pumpPin, LOW);  // Turn off the pump
    } else if (input == 'e') { // 'e' for tank empty
      lcd.clear();
      lcd.print("  Water Running");
      digitalWrite(pumpPin, HIGH); // Turn on the pump
    } else {
      lcd.clear();
      lcd.print("  Invalid Input");
    }
    delay(500); // Wait for a moment to avoid multiple inputs
    return; // Return to the loop to prevent further serial handling
  }

  // If both sensors indicate the tank is full (both HIGH)
  if (tankFull == HIGH && tankEmpty == HIGH) {
    lcd.clear();
    lcd.print("  Tank is full");
    digitalWrite(pumpPin, LOW);  // Turn off the pump
    delay(2000);  // Wait for 2 seconds

    // Wait until the tankFull sensor becomes LOW
    while (tankFull == HIGH) {
      lcd.clear();
      lcd.print("  Tank gg Full");
      delay(100); // Short delay
      tankFull = digitalRead(tankFullPin); // Re-read tankFull
    }

    return; // Exit the loop and start over
  }

  // If both sensors indicate that the tank is empty (both LOW)
  else if (tankFull == LOW && tankEmpty == LOW) {
    lcd.clear();
    lcd.print("  Water Running");
    delay(100);  // Short delay
    digitalWrite(pumpPin, HIGH); // Turn on the pump
  }

  // If one sensor is HIGH and the other is LOW, do nothing
  else {
    return;
  }

  // Additional: Manual control with a button (optional)
  int buttonState = digitalRead(buttonPin); // Read the button state
  if (buttonState == LOW) {  // Button pressed
    lcd.clear();
    lcd.print("  Manual ON");
    digitalWrite(pumpPin, HIGH); // Turn on the pump manually
    delay(1000); // Pump stays on for 1 second (for testing)
  } else {  // Button not pressed
    lcd.clear();
    lcd.print("  Pump OFF");
    digitalWrite(pumpPin, LOW); // Turn off the pump manually
  }
}