/**************************************************************************/
/*!
    This example will attempt to connect to an ISO14443A
    card or tag and retrieve some basic information about it
    that can be used to determine what type of card it is.

    Note that you need the baud rate to be 115200 because we need to print
    out the data and read from the card at the same time!

    To enable debug message, define DEBUG in PN532/PN532_debug.h

*/
/**************************************************************************/

#include <SPI.h>
#include <PN532_SPI.h>
#include "PN532.h"

const int TE_PIN = PD2;
const int BUZZER_PIN = PD3;

// Var to store the last read uid in so we dont spam MQTT
int lastCardUid[] = { 0, 0, 0, 0, 0, 0, 0 };
unsigned long lastRead = 0;
unsigned long lastReadSuccess = 0;

// Track durations
unsigned long buzzerAt = 0;
int buzzerDuration = 500;

PN532_SPI pn532spi(SPI, SS);
PN532 nfc(pn532spi);

void buzzerSet(int duration = 600) {
  digitalWrite(BUZZER_PIN, HIGH);
  buzzerAt = millis();
  buzzerDuration = duration;
}

void buzzerTimeout() {
  if ((millis() - buzzerAt) > buzzerDuration) {
    digitalWrite(BUZZER_PIN, LOW);
  }
}

void setup(void) {
  Serial.begin(9600);
  Serial.println("Hello!");

  nfc.begin();

  uint32_t versiondata = nfc.getFirmwareVersion();
  if (! versiondata) {
    Serial.print("Didn't find PN53x board");
    while (1); // halt
  }

  // Got ok data, print it out!
  Serial.print("Found chip PN5"); Serial.println((versiondata>>24) & 0xFF, HEX);
  Serial.print("Firmware ver. "); Serial.print((versiondata>>16) & 0xFF, DEC);
  Serial.print('.'); Serial.println((versiondata>>8) & 0xFF, DEC);

  // Set the max number of retry attempts to read from a card
  // This prevents us from waiting forever for a card, which is
  // the default behaviour of the PN532.
  nfc.setPassiveActivationRetries(0xFF);

  // configure board to read RFID tags
  nfc.SAMConfig();

  Serial.println("Waiting for an ISO14443A card");
}

void getUidChars(uint8_t uid[], uint8_t uidLength, char* result, const unsigned result_length) {
  char part[] = {};
  for (int i = 0; i < uidLength; i++) {
    sprintf(part, "%02x", uid[i]);
    strcat(result, part);
  }
}

void readRFID() {
  uint8_t success;
  uint8_t uid[] = { 0, 0, 0, 0, 0, 0, 0 };  // Buffer to store the returned UID
  uint8_t uidLength;                        // Length of the UID (4 or 7 bytes depending on ISO14443A card type)

  // Wait for an ISO14443A type cards (Mifare, etc.).  When one is found
  // 'uid' will be populated with the UID, and uidLength will indicate
  // if the uid is 4 bytes (Mifare Classic) or 7 bytes (Mifare Ultralight)
  success = nfc.readPassiveTargetID(PN532_MIFARE_ISO14443A, uid, &uidLength);

  if (success) {
    /*
    Is it the same card that was read then we skip over the rest so we dont
     to verify it below
    */
    int isSame = memcmp(lastCardUid, uid, uidLength);

    if (isSame == 0) {
      Serial.println("Same card detected, skipping");
      return;
    };

    memcpy(lastCardUid, uid, uidLength);

    lastReadSuccess = millis();

    // Display some basic information about the card
    Serial.println("Found an ISO14443A card");
    Serial.print("  UID Length: ");
    Serial.print(uidLength, DEC);
    Serial.println(" bytes");
    Serial.print("  UID Value: ");
    nfc.PrintHex(uid, uidLength);

    if (uidLength == 4) {
      // We probably have a Mifare Classic card ...

      char id[100] = {};
      int idLen = 0;
      getUidChars(uid, uidLength, id, idLen);

      //String credId = String(id);
    }

    Serial.println("");
    return;

    // In case of there wasn't a successfull attempt then we null the lastCardUid
    if ((millis() - lastReadSuccess) > 2000) {
      lastCardUid[0] = 0;
    }
  }
}

void loop() {
  readRFID();
  buzzerTimeout();
}