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

#define REDLED 3
#define GREENLED 2

const int ROW_NUM = 4;
const int COLUMN_NUM = 4;

char keys[ROW_NUM][COLUMN_NUM]{
  {'1','2','3','A'},
  {'4','5','6','B'},
  {'7','8','9','C'},
  {'*','0','#','D'}
};

byte pin_rows[ROW_NUM] = {22, 24, 26, 28};
byte pin_column[COLUMN_NUM] = {23, 25, 27, 29};

LiquidCrystal_I2C lcd(0x27, 16, 2);
Servo motor;
Keypad keypad = Keypad(makeKeymap(keys), pin_rows, pin_column, ROW_NUM, COLUMN_NUM);

const String passcode = "1907";
String input_passcode;

int attempts = 0;

void setup() {
  lcd.init();
  lcd.backlight();
  lcd.setCursor(0, 0);

  motor.attach(4);
  motor.write(90);

  pinMode(REDLED, OUTPUT);
  pinMode(GREENLED, OUTPUT);

  input_passcode.reserve(33);

  lcd.println("***HYDRATECH***");
  lcd.setCursor(0, 1);
  lcd.println("***SECURITY****");
  delay(3000);
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.println("ENTER PASSCODE");
}

void loop() {

  motor.write(90);
  digitalWrite(REDLED, LOW);
  digitalWrite(GREENLED, LOW);

  char key = keypad.getKey();

  if (key) {
    if (input_passcode.length() == 0) {
      lcd.clear();
    }
    lcd.print(key);

    // To delete
    if (key == 'D') {
      input_passcode = "";
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.println("ENTER PASSCODE");
    }

    // To submit passcode
    else if (key == 'C') {
      
      if (passcode == input_passcode) {
        lcd.clear();
        lcd.println("ACCESS GRANTED");
        digitalWrite(GREENLED, HIGH);
        motor.write(0);
        delay(3000);
        lcd.clear();
        attempts = 0;
      } else {
        lcd.clear();
        lcd.println("ACCESS DENIED");
        digitalWrite(REDLED, HIGH);
        delay(3000);
        lcd.clear();
        attempts++;
      } if (attempts > 3){
        wait();
      }

      input_passcode = ""; 
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.println("ENTER PASSCODE");
    } 
    
    else {
      input_passcode += key;
    }
  }
}

void wait(){

  int wait_time = 11;

  for(int i = 0 ; i < 11 ; i++){
    wait_time--;
    lcd.clear();
    lcd.print("Please wait for ");
    lcd.setCursor(0,1);
    lcd.print(wait_time);
    lcd.setCursor(3,1);
    lcd.print("seconds");
    delay(1000);
  }
}