from typing import Union

from public import public
from smartcard.CardConnection import CardConnection
from smartcard.System import readers
from smartcard.pcsc.PCSCCardConnection import PCSCCardConnection
from smartcard.pcsc.PCSCReader import PCSCReader

from .ISO7816 import ISO7816Target, CommandAPDU, ResponseAPDU


@public
class PCSCTarget(ISO7816Target):  # pragma: no cover
    """A smartcard target communicating via PCSC."""

    def __init__(self, reader: Union[str, PCSCReader]):
        if isinstance(reader, str):
            rs = readers()
            for r in rs:
                if r.name == reader:
                    self.reader = r
                    break
            else:
                raise ValueError("Reader '{}' not found.".format(reader))
        else:
            self.reader = reader
        self.connection: PCSCCardConnection = self.reader.createConnection()

    def connect(self):
        self.connection.connect(CardConnection.T0_protocol | CardConnection.T1_protocol)

    @property
    def atr(self) -> bytes:
        return bytes(self.connection.getATR())

    def select(self, aid: bytes) -> bool:
        apdu = CommandAPDU(0x00, 0xa4, 0x04, 0x00, aid)
        resp = self.send_apdu(apdu)
        return resp.sw == 0x9000

    def send_apdu(self, apdu: CommandAPDU) -> ResponseAPDU:
        resp, sw1, sw2 = self.connection.transmit(bytes(apdu))
        return ResponseAPDU(bytes(resp), sw1 << 8 | sw2)

    def disconnect(self):
        self.connection.disconnect()