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

#define I2C_ADDR    0x27
#define LCD_COLUMNS 20
#define LCD_LINES   4

#define buzzer 13
#define red_led 12
#define green_led 11
#define red_button 9
#define yellow_button 8
#define green_button 7

const uint8_t ROWS = 4;
const uint8_t COLS = 3;
char keys[ROWS][COLS] = {
  { '1', '2', '3' },
  { '4', '5', '6' },
  { '7', '8', '9' },
  { '*', '0', '#' }
};

uint8_t colPins[COLS] = { 4, 5, 6 }; 
uint8_t rowPins[ROWS] = { 0, 1, 2, 3 }; 
Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

LiquidCrystal_I2C lcd(I2C_ADDR, LCD_COLUMNS, LCD_LINES);
Servo myservo;

const int max_access_records = 10; 
char granted_access[max_access_records];
char denied_access[max_access_records];
int granted_count = 0;
int denied_count = 0;

bool is_pressed = false;

void setup() {
  lcd.init();
  lcd.backlight();

  pinMode(red_led, OUTPUT);
  pinMode(green_led, OUTPUT);

  pinMode(red_button, INPUT_PULLUP);
  pinMode(green_button, INPUT_PULLUP);
  pinMode(yellow_button, INPUT_PULLUP);

  pinMode(buzzer, OUTPUT);

  myservo.attach(10);
  myservo.write(0);
  Serial.begin(115200);
}

void loop() {
  
  if(digitalRead(red_button) == LOW && !is_pressed){
    red_key();
  }

  if (digitalRead(red_button) == HIGH) {
    is_pressed = false;
  }

  if(digitalRead(green_button) == LOW && !is_pressed){
    green_key();
  }

  if (digitalRead(green_button) == HIGH) {
    is_pressed = false;
  }

  if(digitalRead(yellow_button) == LOW && !is_pressed){
    admin_key();
  }
  
  if (digitalRead(yellow_button) == HIGH) {
    is_pressed = false;
  }

}

void red_key(){
  is_pressed = true;
  turn_led(red_led);
  access_denied();
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Failed access!");
  if(denied_count < max_access_records){
    denied_access[denied_count] = "*";
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.println("Failed attemp # ");
    lcd.setCursor(0, 1);
    lcd.println(denied_count);
    denied_count++;
  } else{
    Serial.println("You have reached the limit!");
  }
}

void green_key(){
  is_pressed = true;
  turn_led(green_led);
  access_granted();
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Successful access!");
  open_door(3000);
  if(granted_count < max_access_records){
    granted_access[granted_count] = "*";
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.println("Successful attemp # ");
    lcd.setCursor(0, 1);
    lcd.println(granted_count);
    granted_count++;
  } else{
    Serial.println("You have reached the limit!");
  }
}

void admin_key(){
  is_pressed = true;
  turn_led(green_led);
  turn_led(red_led);
  turn_led(green_led);
  access_admin();
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.println("Admin access");
  lcd.setCursor(0, 1);
  lcd.println("Enter a pin:");

  String enteredCode = getInputFromKeypad();

  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Code received:");
  lcd.setCursor(0, 1);
  lcd.print(enteredCode);
  Serial.print("Entered code: ");
  Serial.println(enteredCode);

  if (enteredCode == "3897") {
    lcd.clear();
    lcd.print("Successful access!");
    open_door(3000);
  } else {
    lcd.clear();
    lcd.print("Failed access!");
    access_denied();
  }
}

void access_granted(){
  tone(buzzer, 1000, 100);
  delay(200);
  noTone(buzzer);
}

void access_denied(){
  tone(buzzer, 500, 100);
  delay(200);
  noTone(buzzer);
}

void access_admin(){
  tone(buzzer, 100, 100);
  delay(200);
  noTone(buzzer);  
}

void turn_led(int pin){
  digitalWrite(pin, HIGH);
  delay(500);
  digitalWrite(pin, LOW);
}

void open_door(int time){
  myservo.write(90); 
  delay(time);  
  myservo.write(0);
}

String getInputFromKeypad() {
  String input = ""; 
  char key;

  while (true) {
    key = keypad.getKey(); 
    if (key != NO_KEY) {
      if (key == '*') {
        return input;
      } else if (key == '#') {
        input = "";
        lcd.clear();
        lcd.setCursor(0, 0);
        lcd.print("Input cleared!");
        Serial.println("Input cleared!");
      } else {
        if (input.length() < 5) { 
          input += key;
          lcd.setCursor(input.length() - 1, 1); 
          lcd.print(key);
          Serial.print(key);
        } else {
          lcd.setCursor(0, 0);
          lcd.print("Max length reached!");
          Serial.println("Max length reached!");
        }
      }
    }
  }
}