/**
  --------------------------------------------------------------------------------------------------------------------
  Example sketch/program showing how to read data from more than one PICC to serial.
  --------------------------------------------------------------------------------------------------------------------
  This is a MFRC522 library example; for further details and other examples see: https://github.com/miguelbalboa/rfid

  Example sketch/program showing how to read data from more than one PICC (that is: a RFID Tag or Card) using a
  MFRC522 based RFID Reader on the Arduino SPI interface.

  Warning: This may not work! Multiple devices at one SPI are difficult and cause many trouble!! Engineering skill
           and knowledge are required!

  @license Released into the public domain.

  Typical pin layout used:
  -----------------------------------------------------------------------------------------
              MFRC522      Arduino       Arduino   Arduino    Arduino          Arduino
              Reader/PCD   Uno/101       Mega      Nano v3    Leonardo/Micro   Pro Micro
  Signal      Pin          Pin           Pin       Pin        Pin              Pin
  -----------------------------------------------------------------------------------------
  RST/Reset   RST          9             5         D9         RESET/ICSP-5     RST
  SPI SS 1    SDA(SS)      ** custom, take a unused pin, only HIGH/LOW required *
  SPI SS 2    SDA(SS)      ** custom, take a unused pin, only HIGH/LOW required *
  SPI MOSI    MOSI         11 / ICSP-4   51        D11        ICSP-4           16
  SPI MISO    MISO         12 / ICSP-1   50        D12        ICSP-1           14
  SPI SCK     SCK          13 / ICSP-3   52        D13        ICSP-3           15
*/

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

#define RST_1_PIN       8

#define SS_1_PIN        5
#define SS_2_PIN        6
#define SS_3_PIN        7


#define NR_OF_READERS   3

byte ssPins[] = {SS_1_PIN, SS_2_PIN, SS_3_PIN};

MFRC522 mfrc522[NR_OF_READERS];   // Create MFRC522 instance.


const int buttonPin = 2;     // the number of the pushbutton pin
const int ledPin =  3;      // the number of the LED pin

// variables will change:
int buttonState = 0;         // variable for reading the pushbutton status


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

  for (uint8_t reader = 0; reader < NR_OF_READERS; reader++) {
    mfrc522[reader].PCD_Init(ssPins[reader], RST_1_PIN); // Init each MFRC522 card

    Serial.print(F("Reader "));
    Serial.print(reader);
    Serial.print(F(":"));
    mfrc522[reader].PCD_DumpVersionToSerial();
  }

    // initialize the LED pin as an output:
  pinMode(ledPin, OUTPUT);
  // initialize the pushbutton pin as an input:
  pinMode(buttonPin, INPUT);
}

void loop() {

  // delay(50);

  for (uint8_t reader = 0; reader < NR_OF_READERS; reader++) {
    // Look for new cards

    if (mfrc522[reader].PICC_IsNewCardPresent() && mfrc522[reader].PICC_ReadCardSerial()) {
      Serial.print(F("Reader "));
      Serial.print(reader);
      // Show some details of the PICC (that is: the tag/card)
      Serial.print(F(":"));
      dump_byte_array(mfrc522[reader].uid.uidByte, mfrc522[reader].uid.size);
      Serial.println();
      //Serial.print(F("PICC type: "));
      //MFRC522::PICC_Type piccType = mfrc522[reader].PICC_GetType(mfrc522[reader].uid.sak);
      //Serial.println(mfrc522[reader].PICC_GetTypeName(piccType));

      // Halt PICC
      //mfrc522[reader].PICC_HaltA();
      // Stop encryption on PCD
      mfrc522[reader].PCD_StopCrypto1();
}
    else
    {
      Serial.print(F("Reader "));
      Serial.print(reader);
      Serial.print(F(":"));
      Serial.print(F("X"));
      Serial.println();
    }

   // read the state of the pushbutton value:
  buttonState = digitalRead(buttonPin);

  // check if the pushbutton is pressed. If it is, the buttonState is HIGH:
  if (buttonState == HIGH) {
    // turn LED on:
    digitalWrite(ledPin, HIGH);
  } else {
    // turn LED off:
    digitalWrite(ledPin, LOW);
  }

    } //if (mfrc522[reader].PICC_IsNewC
  } //for(uint8_t reader


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