#include <Keypad.h>
#include <Servo.h>
#include <LiquidCrystal.h>
#include <EEPROM.h>

// Define keypad parameters
const byte ROWS = 4; // Four rows
const byte COLS = 4; // Four columns
char keys[ROWS][COLS] = {
  {'1','2','3','A'},
  {'4','5','6','B'},
  {'7','8','9','C'},
  {'*','0','#','D'}
};

// Verify that these pin numbers match your hardware connections
byte rowPins[ROWS] = {A0, A1, A2, A3}; // Row pin numbers
byte colPins[COLS] = {8, 7, 6, 5};     // Column pin numbers

Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

// Define servo motor parameters
Servo servo;
const int servoPin = 9; 

// Define LCD parameters
LiquidCrystal lcd(12, 11, 4, 3, 2, 13);

// Define buzzer parameters
const int buzzerPin = 10; // Change to pin 10

#define NOTE_E5 659
#define NOTE_D5 587
#define NOTE_FS4 370
#define NOTE_GS4 415
#define NOTE_CS5 554
#define NOTE_B4 494
#define NOTE_D4 294
#define NOTE_E4 330
#define NOTE_A4 440
#define NOTE_CS4 277

// Change this to make the song slower or faster
int tempo = 280;

// Notes of the melody followed by the duration
int melody[] = {
  NOTE_E5, 8, NOTE_D5, 8, NOTE_FS4, 4, NOTE_GS4, 4, 
  NOTE_CS5, 8, NOTE_B4, 8, NOTE_D4, 4, NOTE_E4, 4, 
  NOTE_B4, 8, NOTE_A4, 8, NOTE_CS4, 4, NOTE_E4, 4,
  NOTE_A4, 2, 
};

int notes = sizeof(melody) / sizeof(melody[0]) / 2;
int wholenote = (60000 * 4) / tempo;

// Define correct passcode and variables
String enteredPasscode = "";
String correctPasscode = "";

// EEPROM address to store the passcode
const int passcodeAddress = 0;

// Function to read the passcode from EEPROM
String readPasscodeFromEEPROM() {
  String passcode = "";
  char c;
  for (int i = 0; i < 4; i++) {
    c = EEPROM.read(passcodeAddress + i);
    if (c == 0 || c == 255) break;
    passcode += c;
  }
  return passcode;
}

// Function to save the passcode to EEPROM
void savePasscodeToEEPROM(String passcode) {
  for (int i = 0; i < 4; i++) {
    EEPROM.write(passcodeAddress + i, passcode[i]);
  }
}

// Define the DoorControl struct
struct DoorControl {
  Servo* servo;
  LiquidCrystal* lcd;
  String* correctPasscode;
  String* enteredPasscode;
  int* melody;
  int* notes;
  int buzzerPin;
  int wholenote;
};

// Function prototypes
void processKey(DoorControl* dc, char key);
void unlockDoor(DoorControl* dc);
void playMelody(DoorControl* dc);

void setup() {
  Serial.begin(9600);
  servo.attach(servoPin);
  lcd.begin(16, 2);
  lcd.print("Enter Passcode:");
  pinMode(buzzerPin, OUTPUT);

  correctPasscode = readPasscodeFromEEPROM();
  if (correctPasscode == "") {
    correctPasscode = "1234"; // Default passcode if not set
  }
}

void loop() {
  DoorControl doorControl = { &servo, &lcd, &correctPasscode, &enteredPasscode, melody, &notes, buzzerPin, wholenote };
  char key = keypad.getKey();
  if (key) {
    processKey(&doorControl, key);
  }
}

void processKey(DoorControl* dc, char key) {
  if (key == 'C') {
    *(dc->enteredPasscode) = ""; // Clear the entered passcode
    dc->lcd->setCursor(0, 1);
    dc->lcd->print("                "); // Clear previous input
  } else if (key == '#') {
    if (*(dc->enteredPasscode) == *(dc->correctPasscode)) {
      unlockDoor(dc);
    } else {
      dc->lcd->clear();
      dc->lcd->print("Incorrect Passcode!");
      delay(2000);
      dc->lcd->clear();
      dc->lcd->print("Enter Passcode:");
    }
    *(dc->enteredPasscode) = ""; // Reset the entered passcode
  } else if (key == 'A') {
    // Enter new passcode
    dc->lcd->clear();
    dc->lcd->print("New Passcode:");
    delay(1000);
    String newPasscode = "";
    while (newPasscode.length() < 4) {
      char newKey = keypad.getKey();
      if (newKey) {
        newPasscode += newKey;
        dc->lcd->setCursor(0, 1);
        dc->lcd->print(newPasscode);
      }
    }
    *(dc->correctPasscode) = newPasscode;
    savePasscodeToEEPROM(newPasscode);
    dc->lcd->clear();
    dc->lcd->print("Passcode Saved");
    delay(2000);
    dc->lcd->clear();
    dc->lcd->print("Enter Passcode:");
  } else {
    *(dc->enteredPasscode) += key;
    dc->lcd->setCursor(0, 1);
    dc->lcd->print("                "); // Clear previous input
    dc->lcd->setCursor(0, 1);
    dc->lcd->print(*(dc->enteredPasscode));
  }
}

void unlockDoor(DoorControl* dc) {
  dc->lcd->clear();
  dc->lcd->print("Door Unlocked");
  dc->servo->write(0);
  playMelody(dc);
  delay(3000);
  dc->servo->write(90);
  delay(1000);
  dc->lcd->clear();
  dc->lcd->print("Enter Passcode:");
}

void playMelody(DoorControl* dc) {
  for (int thisNote = 0; thisNote < *(dc->notes) * 2; thisNote += 2) {
    int divider = dc->melody[thisNote + 1];
    int noteDuration = 0;

    if (divider > 0) {
      noteDuration = (dc->wholenote) / divider;
    } else if (divider < 0) {
      noteDuration = (dc->wholenote) / abs(divider);
      noteDuration *= 1.5;
    }

    tone(dc->buzzerPin, dc->melody[thisNote], noteDuration * 0.9);
    delay(noteDuration);
    noTone(dc->buzzerPin);
  }
}