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

#define codeLength 4      // Password length is 4 digits
Servo myservo;           // Declare a Servo object
char Code[codeLength];   // Store the entered password
char PassW[codeLength + 1] = "1234"; // Correct password (size 5 for null-terminator)
byte keycount = 0;       // Track how many keys are pressed

// Keypad setup (4x4 matrix)
const uint8_t ROWS = 4;
const uint8_t COLS = 4;
char keys[ROWS][COLS] = {
  {'1','2','3','A'},
  {'4','5','6','B'},
  {'7','8','9','C'},
  {'*','0','#','D'}
};

// Pin connections for the keypad and LCD
uint8_t rowPins[ROWS] = {26, 22, 21, 20}; 
uint8_t colPins[COLS] = {19, 18, 17, 16}; 

// LCD setup (connected to pins 13, 11, 9, 8, 7, 6)
LiquidCrystal lcd(13, 11, 9, 8, 7, 6);
Keypad customKeypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

void setup() {
  lcd.begin(16, 2);          // Initialize LCD (16 columns, 2 rows)
  lcd.print("Enter Code:");  // Display message on LCD
  myservo.attach(28);       // Attach servo to pin 28
}

void loop() {
  char key = customKeypad.getKey();  // Read the pressed key from keypad
  
  if (key) {  // If a key is pressed
    Code[keycount] = key;  // Store the pressed key in Code[]
    lcd.setCursor(5, 1);   // Move cursor to position 5, 1 (second row)
    lcd.print(key);        // Display the pressed key on the screen
    keycount++;            // Increment key count
  }
  
  // Once the full password is entered (4 keys)
  if (keycount == codeLength) {
    delay(500);  // Small delay before checking the password
    
    // Check if the entered password matches the correct password
    if (strcmp(Code, PassW) == 0) {
      lcd.clear();              // Clear the LCD screen
      lcd.setCursor(0, 0);      // Move cursor to the first row
      lcd.print("Correct!");    // Display "Correct!" on the screen
      openAndCloseServo();      // Open and close the servo (unlock action)

    } else {
      lcd.clear();              // Clear the LCD screen
      lcd.setCursor(0, 0);      // Move cursor to the first row
      lcd.print("Wrong! Try Again");  // Display "Wrong! Try Again"
      delay(2000);              // Wait for 2 seconds before clearing
    }

    resetPassword();  // Reset the entered password for the next attempt
  }
}

// Function to move the servo (simulates unlocking action)
void openAndCloseServo() {
  for (int pos = 90; pos <= 180; pos++) {  // Move the servo from 90 to 180 degrees
    myservo.write(pos);    // Move the servo to the new position
    delay(15);             // Wait for the servo to reach the position
  }
  delay(1000);             // Wait for 1 second

  for (int pos = 180; pos >= 90; pos--) {  // Move the servo back from 180 to 90 degrees
    myservo.write(pos);    // Move the servo back to the 90-degree position
    delay(15);             // Wait for the servo to reach the position
  }
}

// Function to reset the entered password (clear Code[] and reset key count)
void resetPassword() {
  keycount = 0;  // Reset keycount to 0
  for (int i = 0; i < codeLength; i++) {
    Code[i] = 0;  // Clear the Code[] array
  }
}