#include <SPI.h>
#include <MFRC522.h>

String card[2] = {
  "A0 EA 57 32" // ---> Valid
  ,
  "A9 C0 15 BA" // ---> Valid
};
const int microwavePin = 4;
const int buzzerPin = 8;
const int ledPin = 7;

String a = "";
MFRC522 mfrc522(10, 9);

int count = 0;
bool seats[2] = {0};
int out = 0;

void setup() {
  Serial.begin(115200);   // Initiate a serial communication
  pinMode(6, OUTPUT);
  digitalWrite(6, 1);
  pinMode(buzzerPin, OUTPUT);
  pinMode(microwavePin, INPUT);
  pinMode(ledPin, OUTPUT);
  SPI.begin();      // Initiate  SPI bus
  mfrc522.PCD_Init();   // Initiate MFRC522
  Serial.print("starting");
}

void loop() {
  // Look for new cards
  if ( ! mfrc522.PICC_IsNewCardPresent())
  {
    return;
  }
  // Select one of the cards
  if ( ! mfrc522.PICC_ReadCardSerial())
  {
    return;
  }
  String content = "";
  byte letter;
  for (byte i = 0; i < mfrc522.uid.size; i++)
  {
    // To show cards UUID, un-comment the next line
    content.concat(String(mfrc522.uid.uidByte[i] < 0x10 ? " 0" : " "));
    content.concat(String(mfrc522.uid.uidByte[i], HEX));
  }
  content.toUpperCase();

  Serial.println(content.substring(1));
  for (int j = 0; j < 2; j++) {
    if (content.substring(1) == card[j]) //change UID of the card that you want to give access
    {

      buzz();
      delay(1000);
      while (1) {
        int microwave = digitalRead(microwavePin);
        if (microwave == 1) {
          digitalWrite(ledPin, HIGH);
          Serial.println(microwave);
          //buzz();
        }
        else {

          digitalWrite(ledPin, LOW);
          digitalWrite(6, 0);
          Serial.println(microwave);
          break;
        }
      }
    }
  }
}// end of loop


void buzz() {
  digitalWrite(buzzerPin, 1);
  delay(100);
  digitalWrite(buzzerPin, 0);
  delay(50);
}