#include <Arduino.h>

const int numRows = 4; 
const int numCols = 4; 
const int debounceTime = 20; 

const char keymap[numRows][numCols] = {
 { '1', '2', '3' ,'A'},
 { '4', '5', '6','B' },
 { '7', '8', '9' ,'C'},
 { '*', '0', '#','D' }
};


const int rowPins[numRows] = {13, 12, 11, 10}; 
const int colPins[numCols] = {9, 8, 7,6}; 

const int greenLedPin = 4; 
const int redLedPin = 5;  

String correctPassword = "AB1234CD";  
String inputPassword = "";        

void setup() {
  Serial.begin(9600);
  
  
  for (int row = 0; row < numRows; row++) {
    pinMode(rowPins[row], INPUT_PULLUP); 
  }
  for (int column = 0; column < numCols; column++) {
    pinMode(colPins[column], OUTPUT); 
    digitalWrite(colPins[column], HIGH);
     
  }

  pinMode(greenLedPin, OUTPUT);
  pinMode(redLedPin, OUTPUT);

  
  digitalWrite(greenLedPin, LOW); 
  digitalWrite(redLedPin, LOW);
}

void loop() {
  
  char key = getKey();
 
  if (key == '#') {
   
    if (inputPassword == correctPassword) {

      digitalWrite(greenLedPin, HIGH);
      delay(2000);                 
      digitalWrite(greenLedPin, LOW);
    } else {
      digitalWrite(redLedPin, HIGH);
      delay(2000);
      digitalWrite(redLedPin, LOW);
    }
    
    inputPassword = "";
    
  } else if (key != 0) {
    Serial.print(key);
    // اذا اردنا ان لا تظهر كلمه المرور
    // Serial.print(key);اثناء الكتابه نحذف الكلمه اعلاه
    inputPassword += key; 
    
  }

}

char getKey() {

  char key = 0;

  for (int column = 0; column < numCols; column++) {
    digitalWrite(colPins[column], LOW); 
    for (int row = 0; row < numRows; row++) {
      if (digitalRead(rowPins[row]) == LOW) { 
        delay(debounceTime); 
        while (digitalRead(rowPins[row]) == LOW); 
        key = keymap[row][column]; 
      }
    }
    digitalWrite(colPins[column], HIGH); 

  }
  return key; 
  
}