Pickpockets Beware!

/* Name: Sophie Wang, Sara Li, Annie Zou, Aaiza Khalid
Project: Pickpocketing Detector 
Date: Feb 17th, 2019

Purpose: To warn users and protect their bags from potential pickpocketing threats 

Outline:
   1. user clips the device onto the zipper of their bag
   2. user puts on the key reader/ ring on their finger 
   3. device continuously checks for potential pickpocketing threats 
   4. if person going into bag does not have ring on - the device will          alert the owner

Testing:
       - tested the distance of the zipper opening that will trigger the           sensor
       - tested the connection between TELUS LTE-M IoT Starter Kit and the          device
       - tested the connectivity between the wires
       - tested the sensitivity of the sensors by using different mediums 
         to break the beam connection

Restrictions:
       - current prototype is too large to carry 
       - should have a better sound system rather than just an LED                 light to warn the user
*/
 
#include "SPI.h"
#include "MFRC522.h"

#define SS_PIN 10
#define RST_PIN 9
#define SP_PIN 8
#define LED_PIN 7
#define BEAM 4

MFRC522 rfid(SS_PIN, RST_PIN);

MFRC522::MIFARE_Key key;

void setup() {
 Serial.begin(9600);
 SPI.begin();
 rfid.PCD_Init();
 pinMode(LED_PIN, OUTPUT);
 pinMode(BEAM, INPUT);
 digitalWrite(LED_PIN, LOW);
}

void loop() {
 digitalWrite(LED_PIN, !digitalRead(BEAM));
 if (!rfid.PICC_IsNewCardPresent() || !rfid.PICC_ReadCardSerial())
   return;

 // Serial.print(F("PICC type: "));
 MFRC522::PICC_Type piccType = rfid.PICC_GetType(rfid.uid.sak);
 // Serial.println(rfid.PICC_GetTypeName(piccType));

 // Check is the PICC of Classic MIFARE type
 if (piccType != MFRC522::PICC_TYPE_MIFARE_MINI &&
   piccType != MFRC522::PICC_TYPE_MIFARE_1K &&
   piccType != MFRC522::PICC_TYPE_MIFARE_4K) {
   Serial.println(F("Your tag is not of type MIFARE Classic."));
   return;
 }

 String strID = "";
 for (byte i = 0; i < 4; i++) {
   strID +=
   (rfid.uid.uidByte[i] < 0x10 ? "0" : "") +
   String(rfid.uid.uidByte[i], HEX) +
   (i!=3 ? ":" : "");
 }
 strID.toUpperCase();

 Serial.print("Tap card key: ");
 Serial.println(strID);

 if (strID == "A0:AE:DD:87") {
   digitalWrite(LED_PIN, LOW);
   delay(5000);
 } else {
   digitalWrite(LED_PIN, HIGH);
 }

 rfid.PICC_HaltA();
 rfid.PCD_StopCrypto1();
}