#include <EEPROM.h>
#include <LiquidCrystal.h>
#include <Wire.h> // Include the Wire library for I2C communication
#include <Adafruit_SSD1306.h> // Include the Adafruit SSD1306 library for OLED display
#include <DHT.h> // Include the DHT library for DHT22 sensor
#include <NewPing.h> // Include the NewPing library for ultrasonic sensor

#define OLED_RESET 4
Adafruit_SSD1306 display(OLED_RESET); // Define OLED display object

#define DHTPIN 8
#define DHTTYPE DHT22
DHT dht(DHTPIN, DHTTYPE); // Define DHT sensor object

#define TRIGGER_PIN 9
#define ECHO_PIN 10
#define MAX_DISTANCE 200
NewPing sonar(TRIGGER_PIN, ECHO_PIN, MAX_DISTANCE); // Define ultrasonic sensor object

long duration, inches;
int set_val, percentage;
bool state, pump;

void setup() {
  Serial.begin(9600);
  
  // Initialize the OLED display
  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;);
  }

  // Set up the text size and color
  display.setTextColor(WHITE);
  display.setTextSize(1);
  display.setCursor(0,0);
  
  // Initialize the DHT sensor
  dht.begin();
  
  // Initialize the water level monitoring system
  pinMode(TRIGGER_PIN, OUTPUT);
  pinMode(ECHO_PIN, INPUT);
  pinMode(12, OUTPUT);
  
  lcd.begin(16, 2);
  lcd.print("WATER LEVEL:");
  lcd.setCursor(0, 1); 
  lcd.print("PUMP:OFF MANUAL");
  
  set_val = EEPROM.read(0);
  if(set_val > 150) set_val = 150;
}

void loop() {
  // Read temperature and humidity from DHT sensor
  float temperature = dht.readTemperature();
  float humidity = dht.readHumidity();
  
  // Display temperature and humidity on OLED display
  display.clearDisplay();
  display.setCursor(0,0);
  display.print("Temp: ");
  display.println(temperature);
  display.print("Humidity: ");
  display.println(humidity);
  display.display();
  
  // Read water level from ultrasonic sensor
  digitalWrite(TRIGGER_PIN, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIGGER_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIGGER_PIN, LOW);
  duration = pulseIn(ECHO_PIN, HIGH);
  inches = microsecondsToInches(duration);
  
  // Calculate percentage of water level
  percentage = (set_val - inches) * 100 / set_val;
  
  // Display water level percentage on LCD
  lcd.setCursor(12, 0);
  if(percentage < 0) percentage = 0;
  lcd.print(percentage);
  lcd.print("%   ");
  
  // Check for leaks or abnormal water flow
  if(inches == 0 || inches >= MAX_DISTANCE) {
    // Leak or abnormal flow detected, activate alarm and shut off pump
    digitalWrite(12, LOW); // Turn off pump
    tone(13, 1000); // Activate buzzer
  } else {
    // Normal water level, deactivate alarm and pump as necessary
    noTone(13); // Turn off buzzer
    if(percentage < 30 && digitalRead(11)) {
      pump = true;
    } else {
      pump = false;
    }
    digitalWrite(12, pump ? HIGH : LOW); // Control the pump
  }
  
  // Save new set_val if manual switch pressed
  if(digitalRead(10) == LOW && !state) {
    state = true;
    set_val = inches;
    EEPROM.write(0, set_val);
  } else if(digitalRead(10) == HIGH) {
    state = false;
  }
  
  // Enter low-power mode
  set_sleep_mode(SLEEP_MODE_PWR_DOWN);
  sleep_enable();
  sleep_mode();
}

long microsecondsToInches(long microseconds) {
  return microseconds / 74 / 2;
}