# -*- coding: utf-8 -*-
#
# Copyright 2020 Nitrokey Developers
#
# Licensed under the Apache License, Version 2.0, <LICENSE-APACHE or
# http://apache.org/licenses/LICENSE-2.0> or the MIT license <LICENSE-MIT or
# http://opensource.org/licenses/MIT>, at your option. This file may not be
# copied, modified, or distributed except according to those terms.


from subprocess import check_output
from sys import stderr, stdout
from time import sleep

import click
from tqdm import tqdm
from usb.core import USBError

from pynitrokey.helpers import local_critical, local_print
from pynitrokey.start.gnuk_token import OnlyBusyICCError, get_gnuk_device
from pynitrokey.start.threaded_log import ThreadLog
from pynitrokey.start.upgrade_by_passwd import (
    DEFAULT_PW3,
    DEFAULT_WAIT_FOR_REENUMERATION,
    IS_LINUX,
    kill_smartcard_services,
    logger,
    restart_smartcard_services,
    show_kdf_details,
    start_update,
    validate_gnuk,
    validate_regnual,
)
from pynitrokey.start.usb_strings import get_devices as get_devices_strings

# @fixme: add 'version' for consistency with fido2


# https://pocoo-click.readthedocs.io/en/latest/commands/#nested-handling-and-contexts
@click.group()
def start():
    """Interact with Nitrokey Start devices, see subcommands."""
    pass


@click.command()
@click.option(
    "--verbose", default=False, is_flag=True, help="Print all available information."
)
def list(verbose=False):
    """list connected devices"""
    local_print(":: 'Nitrokey Start' keys:")
    for dct in get_devices_strings():
        local_print(
            f"{dct['Serial']}: {dct['Vendor']} " f"{dct['Product']} ({dct['Revision']})"
        )
        if verbose:
            local_print(f"{dct}")


@click.command()
@click.option("--count", default=64, type=int, help="Number of bytes to get.")
@click.option(
    "--raw", default=False, is_flag=True, help="Get raw bytes (ASCII by default)."
)
@click.option("--quiet", default=False, is_flag=True, help="Do not show progress bar.")
def rng(count, raw, quiet):
    """Get random data from device by executing GET CHALLENGE command."""
    gnuk = get_gnuk_device(verbose=False)
    gnuk.cmd_select_openpgp()
    i = 0
    with tqdm(
        total=count,
        file=stderr,
        disable=quiet or not raw,
        unit="B",
        unit_scale=True,
        unit_divisor=1024,
    ) as bar:
        while i < count:
            try:
                challenge = gnuk.cmd_get_challenge().tobytes()
                # cap at count bytes
                challenge = challenge[: count - i]
                i += len(challenge)
                bar.update(len(challenge))
            except Exception as e:
                print(count)
                raise e
            if raw:
                stdout.buffer.write(challenge)
            else:
                print(challenge.hex())


@click.command()
@click.argument("identity")
@click.option(
    "--force-restart",
    is_flag=True,
    help="Force pcscd and GnuPG services restart once finished",
)
def set_identity(identity, force_restart):
    """Set given identity (one of: 0, 1, 2)

    Might require stopping other smart card services to connect directly to the device over CCID interface.
    These will be restarted after operation, if it is required.

    This could be replaced with:

    gpg-connect-agent "SCD APDU 00 85 00 0<IDENTITY>"
    """
    if not identity.isdigit():
        local_critical("identity number must be a digit")

    identity = int(identity)
    if identity < 0 or identity > 2:
        local_critical("identity must be 0, 1 or 2")

    local_print(f"Setting identity to {identity}")
    for x in range(3):
        try:
            gnuk = get_gnuk_device()
            with gnuk.release_on_exit() as gnuk:
                gnuk.cmd_select_openpgp()
                try:
                    gnuk.cmd_set_identity(identity)
                    break
                except USBError:
                    local_print(f"Reset done - now active identity: {identity}")
                    break

        except OnlyBusyICCError:
            local_print(
                "Device is occupied by some other service and cannot be connected to. Identity not changed."
            )
            break
        except ValueError as e:
            if "No ICC present" in str(e):
                local_print(
                    "Device is occupied by some other service and cannot be connected to. Identity not changed."
                )
            else:
                local_critical(e)
        except Exception as e:
            local_critical(e)


@click.command()
@click.option(
    "--regnual", default=None, callback=validate_regnual, help="path to regnual binary"
)
@click.option(
    "--gnuk", default=None, callback=validate_gnuk, help="path to gnuk binary"
)
@click.option(
    "-f",
    "default_password",
    is_flag=True,
    default=False,
    help=f"use default Admin PIN: {DEFAULT_PW3}",
)
@click.option("-p", "password", help="use provided Admin PIN")
@click.option(
    "-e",
    "wait_e",
    default=DEFAULT_WAIT_FOR_REENUMERATION,
    type=int,
    help="time to wait for device to enumerate, after regnual was executed on device",
)
@click.option("-k", "keyno", default=0, type=int, help="selected key index")
@click.option("-v", "verbose", default=0, type=int, help="verbosity level")
@click.option("-y", "yes", default=False, is_flag=True, help="agree to everything")
@click.option(
    "-b",
    "skip_bootloader",
    default=False,
    is_flag=True,
    help="Skip bootloader upload (e.g. when done so already)",
)
@click.option(
    "--green-led",
    is_flag=True,
    default=False,
    help="Use firmware for early 'Nitrokey Start' key hardware revisions",
)
def update(
    regnual,
    gnuk,
    default_password,
    password,
    wait_e,
    keyno,
    verbose,
    yes,
    skip_bootloader,
    green_led,
):
    """update device's firmware"""

    args = (
        regnual,
        gnuk,
        default_password,
        password,
        wait_e,
        keyno,
        verbose,
        yes,
        skip_bootloader,
        green_led,
    )

    if green_led and (regnual is None or gnuk is None):
        local_critical(
            "You selected the --green-led option, please provide '--regnual' and "
            "'--gnuk' in addition to proceed. ",
            "use one from: https://github.com/Nitrokey/nitrokey-start-firmware)",
        )

    if IS_LINUX:
        with ThreadLog(logger.getChild("dmesg"), "dmesg -w"):
            start_update(*args)
    else:
        start_update(*args)


@click.command()
@click.option("--passwd", default="", help="password")
def kdf_details(passwd):
    return show_kdf_details(passwd)


start.add_command(rng)
start.add_command(list)
start.add_command(set_identity)
start.add_command(update)
start.add_command(kdf_details)
