#include "SPI.h"
#include "MFRC522.h"

#define RST_PIN         9          // Configurable, see typical pin layout above
#define SS_PIN          10         // Configurable, see typical pin layout above

#define RFID_NR 2

MFRC522 mfrc522(SS_PIN, RST_PIN);  // Create MFRC522 instance

void setup() {
  Serial.begin(9600);   // Initialize serial communications with the PC
  while (!Serial);    // Do nothing if no serial port is opened (added for Arduinos based on ATMEGA32U4)
  SPI.begin();      // Init SPI bus
  mfrc522.PCD_Init();   // Init MFRC522
  delay(4);       // Optional delay. Some board do need more time after init to be ready, see Readme
  mfrc522.PCD_DumpVersionToSerial();  // Show details of PCD - MFRC522 Card Reader details
  Serial.println(F("Scan PICC to see UID, SAK, type, and data blocks..."));
}

byte nuidPICC[RFID_NR][4];

int rfid_nr = 0;

/**
 * Helper routine to dump a byte array as hex values to Serial. 
 */
void printHex(byte *buffer, byte bufferSize) {
  for (byte i = 0; i < bufferSize; i++) {
    Serial.print(buffer[i] < 0x10 ? " 0" : " ");
    Serial.print(buffer[i], HEX);
  }
}

bool compareBytes(byte current[4] , byte last[4])
{
   for (byte i = 0; i < 4; i++) {
     if( current[i] != last[i])
      return false;
    }
    return true;
}

void addNewCard(MFRC522 mfrc522)
{
    for (byte i = 0; i < 4; i++) {
      nuidPICC[rfid_nr][i] = mfrc522.uid.uidByte[i];
    }

    Serial.println(F("The NUID tag is:"));
    Serial.print(F("In hex: "));
    printHex(nuidPICC[rfid_nr], mfrc522.uid.size);


    if(rfid_nr > 0 )
    {
      if (!compareBytes( nuidPICC[rfid_nr], nuidPICC[0]))
        rfid_nr++;
    }else
    {
      rfid_nr++;
    }
}
  
void loop() {
  // Reset the loop if no new card present on the sensor/reader. This saves the entire process when idle.
  if ( ! mfrc522.PICC_IsNewCardPresent()) {
    return;
  }

  // Select one of the cards
  if ( ! mfrc522.PICC_ReadCardSerial()) {
    return;
  }
  if(rfid_nr < RFID_NR)
  {
    addNewCard(mfrc522);
  }else{
    byte currentCard[4];
    for (byte i = 0; i < 4; i++) {
      currentCard[i] = mfrc522.uid.uidByte[i];
    }
    if (compareBytes(currentCard, nuidPICC[0]) || compareBytes(currentCard, nuidPICC[1]))
    {
      Serial.println("Komnata tajemnic stoi otworem!!!");
    }
    else
    {
      Serial.println("Komnata tajemnic jest dalej zamknieta!!!");
    }
  }
}
 
  

/*
 * Po przylozeniu klucza do czytnika program wyswietla na monitorze portuszeregowego informacje o kluczu PICC.
 * Podaje UID, SAK, typ i blok danych
 */

// https://github.com/miguelbalboa/rfid/blob/master/examples/DumpInfo/DumpInfo.ino