#include <SPI.h>
#include <MFRC522.h>
#include <Wire.h>
#include <LiquidCrystal_I2C.h>

// RFID
#define SS_PIN 21
#define RST_PIN 22
MFRC522 mfrc522(SS_PIN, RST_PIN);

// LCD
LiquidCrystal_I2C lcd(0x27, 16, 2);

// LED
#define LED_PIN 5

// مصفوفة UID → اسم الطالب
struct Student {
  String uid;
  String name;
};

Student students[] = {
  {"A1B2C3D4", "Ali"},
  {"55667788", "Sara"},
  {"DEADBEEF", "Mohammed"}
};

void setup() {
  Serial.begin(115200);
  SPI.begin();
  mfrc522.PCD_Init();

  Wire.begin(16,17); // SDA=16, SCL=17
  lcd.init();
  lcd.backlight();
  lcd.setCursor(0,0);
  lcd.print("Scan your card...");

  pinMode(LED_PIN, OUTPUT);
  digitalWrite(LED_PIN, LOW);

  Serial.println("Ready to read RFID cards...");
}

void loop() {
  if (!mfrc522.PICC_IsNewCardPresent()) return;
  if (!mfrc522.PICC_ReadCardSerial()) return;

  // قراءة UID
  String uidStr = "";
  for (byte i = 0; i < mfrc522.uid.size; i++) {
    if (mfrc522.uid.uidByte[i] < 0x10) uidStr += "0";
    uidStr += String(mfrc522.uid.uidByte[i], HEX);
  }
  uidStr.toUpperCase(); // لتوحيد التنسيق
  Serial.print("Card UID: "); Serial.println(uidStr);

  // البحث عن الاسم
  String studentName = "Unknown";
  for (int i = 0; i < sizeof(students)/sizeof(students[0]); i++) {
    if (uidStr == students[i].uid) {
      studentName = students[i].name;
      break;
    }
  }

  // عرض الاسم على LCD
  lcd.clear();
  lcd.setCursor(0,0);
  lcd.print("Student:");
  lcd.setCursor(0,1);
  lcd.print(studentName);

  // تشغيل LED إذا تعرف على الطالب
  if (studentName != "Unknown") {
    digitalWrite(LED_PIN, HIGH);
  } else {
    digitalWrite(LED_PIN, LOW);
  }

  delay(3000); // تأخير لعرض الاسم
  lcd.clear();
  lcd.setCursor(0,0);
  lcd.print("Scan your card...");
  digitalWrite(LED_PIN, LOW);

  mfrc522.PICC_HaltA();
}