#include <Keypad.h>

// Define the rows and columns
const byte ROWS = 4;
const byte COLS = 4;

// Keypad button layout
char keys[ROWS][COLS] = {
  {'1', '2', '3', 'A'},
  {'4', '5', '6', 'B'},
  {'7', '8', '9', 'C'},
  {'*', '0', '#', 'D'}
};

// Pin connections to the keypad
byte rowPins[ROWS] = {2, 3, 4, 5};  // Connect to the row pins
byte colPins[COLS] = {6, 7, 8, 9};  // Connect to the column pins

// Create the Keypad object
Keypad keypad = Keypad(makeKeymap(keys), rowPins, colPins, ROWS, COLS);

// Define the sequences
char correctSequence[4] = {'1', '2', '3', '4'};
char currentSequence[4] = {'4', '3', '2', '1'};
char enteredSequence[4];  // Store entered keys
int position = 0;         // Tracks the current position in the sequence

const int beeperPin = 10;

void setup() {
  pinMode(beeperPin, OUTPUT);
  Serial.begin(9600);
  Serial.println("Enter the correct sequence:");
}

void loop() {
  char key = keypad.getKey();  // Get a key press

  if (key) {  // If a key is pressed
    Serial.print("Key pressed : ");
    Serial.println(key);

    // Store the key in the entered sequence
    enteredSequence[position] = key;
    position++;

    // Check if the sequence is complete
    if (position == 4) {
      // Compare entered sequence with both possible correct sequences
      bool matchesCorrect = true;
      bool matchesCurrent = true;

      for (int i = 0; i < 4; i++) {
        if (enteredSequence[i] != correctSequence[i]) {
          matchesCorrect = false;
        }
        if (enteredSequence[i] != currentSequence[i]) {
          for (int j = 0; j < 4; j++){
            currentSequence[j] = enteredSequence[j];
          }
          matchesCurrent = false;

        }
      }

      if (matchesCorrect || matchesCurrent) {
        Serial.println("the passcode was Correct ");
        tone(beeperPin, 2000, 200); 
      } else {
        Serial.println("the passcode was Wrong ");
        for (int z =0; z < 4; z++){
          Serial.print(currentSequence[z]);
          Serial.print(" ");
        }
        Serial.println("is now the passcode as well ");
        tone(beeperPin, 300, 200); 
      }

      // Reset for the next attempt
      position = 0;
    }
  }
}