import time
import pyperclip

from smartcard.CardRequest import CardRequest
from smartcard.Exceptions import CardConnectionException
from smartcard.CardConnection import CardConnection
from smartcard.util import toHexString

from card_reader import read_card

CLIPBOARD_MESSAGE_PREFIX = "ezgglan-clipboard-message:"


class ClipboardReaderService:
    def __init__(self) -> None:
        self._is_running = True
        self._last_uid = None

    def run(self) -> None:
        print("Reader ready.")

        while self._is_running:
            try:
                card_request = CardRequest(timeout=None)
                card_service = card_request.waitforcard()
                connection = card_service.connection

                try:
                    connection.connect(CardConnection.T1_protocol)

                    GET_UID = [0xFF, 0xCA, 0x00, 0x00, 0x00]
                    uid, sw1, sw2 = connection.transmit(GET_UID)

                    if sw1 != 0x90:
                        raise CardConnectionException("UID read failed")

                    uid_hex = toHexString(uid)

                    if uid_hex == self._last_uid:
                        connection.disconnect()
                        time.sleep(0.5)
                        continue

                    self._last_uid = uid_hex

                    user_id = read_card(connection)

                    if user_id is not None:
                        pyperclip.copy(CLIPBOARD_MESSAGE_PREFIX + str(user_id))
                    else:
                        pyperclip.copy(CLIPBOARD_MESSAGE_PREFIX + "Fehler: Erneut scannen")

                except CardConnectionException:
                    pass

                finally:
                    try:
                        connection.disconnect()
                    except:
                        pass

                time.sleep(0.5)

            except (KeyboardInterrupt, SystemExit):
                self.stop()

    def stop(self) -> None:
        self._is_running = False

if __name__ == "__main__":
    service = ClipboardReaderService()
    service.run()