One Time password based circuit breaker

Projects General Guidance
3 
#include <Password.h>
#include <Keypad.h> 
#include<LiquidCrystal.h>
const int rs = 12, en = 11, d4 = 5, d5 = 4, d6 = 3, d7 = 2;
LiquidCrystal lcd(rs, en, d4, d5, d6, d7);
#include <GSMSim.h>


#define BAUD 9600

long randNumber;
GSMSim gsm;

Password password = Password( randNumber);
int relay_pin = 10;

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

byte rowPins[ROWS] = { 9,8,7,6 };
byte colPins[COLS] = { A0,A1,A2,A3 };


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

void setup(){
  pinMode(relay_pin, OUTPUT);

 lcd.begin(16,2);

 lcd.print(" Design project");

 lcd.setCursor(0,1);

 lcd.print(" circuit breaker");

 delay(2000);

 lcd.clear();

Serial.begin(9600);


 randomSeed(analogRead(0));
 
randNumber = random(1000,9999);

 Serial.println(randNumber);

 
 delay(1000);
 lcd.setCursor(0,1);
 Serial.begin(9600);

 Serial.println("GSMSim Library - SMS Example");
 Serial.println("");
 delay(1000);

 gsm.start(); // baud default 9600
 //gsm.start(BAUD);

 Serial.println("Changing to text mode.");
 gsm.smsTextMode(true);

 char* number = "+9********";
 char* message = randNumber;

 Serial.println("Sending Message --->");
 Serial.println(gsm.smsSend(number, message)); 
 delay(2000);

 
 keypad.addEventListener(keypadEvent); 



 Serial.begin(9600);
 keypad.addEventListener(keypadEvent); 
}

void loop(){
 keypad.getKey();
}

//take care of some special events
void keypadEvent(KeypadEvent eKey){
 switch (keypad.getState()){
   case PRESSED:
lcd. print("Pressed: ");
lcd.println(eKey);
switch (eKey){
 case '*': checkPassword(); break;
 case '#': password.reset(); break;
 default: password.append(eKey);
    }
 }
}

void checkPassword(){
 if (password.evaluate()){
  lcd.println("Success");
  
 }else{
  lcd.println("Wrong");
   
 }
}