//len
#include <LiquidCrystal_I2C.h>
#include <Keypad.h>

LiquidCrystal_I2C lcd(0x27, 20, 4);
int urutan = 1;
const int PINLED = 12;
const byte ROWS = 4;
const byte COLS = 4;
char Keys[ROWS][COLS] = {
  { '1', '2', '3', 'A' },
  { '4', '5', '6', 'B' },
  { '7', '8', '9', 'C' },
  { '*', '0', '#', 'D' }
};
byte rowPins[ROWS] = { 9, 8, 7, 6 };
byte colPins[COLS] = { 5, 4, 3, 2 };
Keypad customKEY = Keypad(makeKeymap(Keys), rowPins,
                          colPins, ROWS, COLS);
String INPUT_PW = "";
String PW[3] = { "1122", "2233", "3311" };

int trigPin = 11;
int echoPin = 10;

void setup() {
  lcd.init();
  lcd.backlight();
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(PINLED, OUTPUT);
}
void loop() {
  lcd.setCursor(0, 0);
  lcd.print("PASSWORD  ");
  lcd.print(urutan);
  lcd.print(": ");

  char KEY = customKEY.getKey();

  if (KEY >= '0' && KEY <= '9') {
    INPUT_PW += KEY;
    lcd.setCursor(0, 1);
    lcd.print(INPUT_PW);
  }

  if (KEY == '#') {
    if (INPUT_PW == PW[urutan - 1]) {
      lcd.setCursor(0, 2);
      lcd.print("PASSWORD BENAR");
      delay(1000);
      lcd.clear();
      INPUT_PW = "";
      urutan++;
      if (urutan == 4) {
        lcd.setCursor(0, 0);
        lcd.print("SENSOR WATERLEVEL");
        lcd.setCursor(0, 1);
        lcd.print("SIAP MEMONITORING");
        delay(1000);
        lcd.clear();
        while (true) {
          float distance = calculateDistance();
          lcd.setCursor(0, 0);
          lcd.print("JARAK: ");
          lcd.print(distance);
          lcd.setCursor(10, 0);
          lcd.print("   cm");
          delay(200);
          KEY = customKEY.getKey();
          if (KEY == '*') {
            lcd.clear();
            urutan = 1;
            break;
          }
        }
      }
    } else {
      lcd.setCursor(0, 2);
      lcd.print("PASSWORD SALAH");
      digitalWrite(PINLED, HIGH);
      delay(1000);
      digitalWrite(PINLED, LOW);
      INPUT_PW = "";
      lcd.clear();
    }
  }

  if (KEY == '*') {
    INPUT_PW = "";
    lcd.clear();
    urutan = 1;
  }
}

int calculateDistance() {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  float duration = pulseIn(echoPin, HIGH);
  float distance = duration / 2 * 0.034;
  return distance;
}