pySim/filesystem.py

# coding=utf-8
"""Representation of the ISO7816-4 filesystem model.

The File (and its derived classes) represent the structure / hierarchy
of the ISO7816-4 smart card file system with the MF, DF, EF and ADF
entries, further sub-divided into the EF sub-types Transparent, Linear Fixed, etc.

The classes are intended to represent the *specification* of the filesystem,
not the actual contents / runtime state of interacting with a given smart card.
"""

# (C) 2021 by Harald Welte <laforge@osmocom.org>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

import code
import tempfile
import json
import abc
import inspect

import cmd2
from cmd2 import CommandSet, with_default_category, with_argparser
import argparse

from typing import cast, Optional, Iterable, List, Dict, Tuple, Union

from smartcard.util import toBytes

from pySim.utils import sw_match, h2b, b2h, i2h, is_hex, auto_int, bertlv_parse_one, Hexstr
from pySim.construct import filter_dict, parse_construct
from pySim.exceptions import *
from pySim.jsonpath import js_path_find, js_path_modify
from pySim.commands import SimCardCommands

# int: a single service is associated with this file
# list: any of the listed services requires this file
# tuple: logical-and of the listed services requires this file
CardFileService = Union[int, List[int], Tuple[int, ...]]

def lchan_nr_from_cla(cla: int) -> int:
    """Resolve the logical channel number from the CLA byte."""
    # TS 102 221 10.1.1 Coding of Class Byte
    if cla >> 4 in [0x0, 0xA, 0x8]:
        # Table 10.3
        return cla & 0x03
    elif cla & 0xD0 in [0x40, 0xC0]:
        # Table 10.4a
        return 4 + (cla & 0x0F)
    else:
        raise ValueError('Could not determine logical channel for CLA=%2X' % cla)

class CardFile:
    """Base class for all objects in the smart card filesystem.
    Serve as a common ancestor to all other file types; rarely used directly.
    """
    RESERVED_NAMES = ['..', '.', '/', 'MF']
    RESERVED_FIDS = ['3f00']

    def __init__(self, fid: str = None, sfid: str = None, name: str = None, desc: str = None,
                 parent: Optional['CardDF'] = None, profile: Optional['CardProfile'] = None,
                 service: Optional[CardFileService] = None):
        """
        Args:
            fid : File Identifier (4 hex digits)
            sfid : Short File Identifier (2 hex digits, optional)
            name : Brief name of the file, lik EF_ICCID
            desc : Description of the file
            parent : Parent CardFile object within filesystem hierarchy
            profile : Card profile that this file should be part of
            service : Service (SST/UST/IST) associated with the file
        """
        if not isinstance(self, CardADF) and fid == None:
            raise ValueError("fid is mandatory")
        if fid:
            fid = fid.lower()
        self.fid = fid           # file identifier
        self.sfid = sfid         # short file identifier
        self.name = name         # human readable name
        self.desc = desc         # human readable description
        self.parent = parent
        if self.parent and self.parent != self and self.fid:
            self.parent.add_file(self)
        self.profile = profile
        self.service = service
        self.shell_commands = []  # type: List[CommandSet]

        # Note: the basic properties (fid, name, ect.) are verified when
        # the file is attached to a parent file. See method add_file() in
        # class Card DF

    def __str__(self):
        if self.name:
            return self.name
        else:
            return self.fid

    def _path_element(self, prefer_name: bool) -> Optional[str]:
        if prefer_name and self.name:
            return self.name
        else:
            return self.fid

    def fully_qualified_path(self, prefer_name: bool = True) -> List[str]:
        """Return fully qualified path to file as list of FID or name strings.

        Args:
            prefer_name : Preferably build path of names; fall-back to FIDs as required
        """
        if self.parent and self.parent != self:
            ret = self.parent.fully_qualified_path(prefer_name)
        else:
            ret = []
        elem = self._path_element(prefer_name)
        if elem:
            ret.append(elem)
        return ret

    def fully_qualified_path_fobj(self) -> List['CardFile']:
        """Return fully qualified path to file as list of CardFile instance references."""
        if self.parent and self.parent != self:
            ret = self.parent.fully_qualified_path_fobj()
        else:
            ret = []
        if self:
            ret.append(self)
        return ret

    def build_select_path_to(self, target: 'CardFile') -> Optional[List['CardFile']]:
        """Build the relative sequence of files we need to traverse to get from us to 'target'."""
        cur_fqpath = self.fully_qualified_path_fobj()
        target_fqpath = target.fully_qualified_path_fobj()
        inter_path = []
        cur_fqpath.pop()  # drop last element (currently selected file, doesn't need re-selection
        cur_fqpath.reverse()
        for ce in cur_fqpath:
            inter_path.append(ce)
            for i in range(0, len(target_fqpath)-1):
                te = target_fqpath[i]
                if te == ce:
                    for te2 in target_fqpath[i+1:]:
                        inter_path.append(te2)
                    # we found our common ancestor
                    return inter_path
        return None

    def get_mf(self) -> Optional['CardMF']:
        """Return the MF (root) of the file system."""
        if self.parent == None:
            return None
        # iterate towards the top. MF has parent == self
        node = self
        while node.parent and node.parent != node:
            node = node.parent
        return cast(CardMF, node)

    def _get_self_selectables(self, alias: str = None, flags=[]) -> Dict[str, 'CardFile']:
        """Return a dict of {'identifier': self} tuples.

        Args:
            alias : Add an alias with given name to 'self' 
            flags : Specify which selectables to return 'FIDS' and/or 'NAMES';
                    If not specified, all selectables will be returned.
        Returns:
            dict containing reference to 'self' for all identifiers.
        """
        sels = {}
        if alias:
            sels.update({alias: self})
        if self.fid and (flags == [] or 'FIDS' in flags):
            sels.update({self.fid: self})
        if self.name and (flags == [] or 'FNAMES' in flags):
            sels.update({self.name: self})
        return sels

    def get_selectables(self, flags=[]) -> Dict[str, 'CardFile']:
        """Return a dict of {'identifier': File} that is selectable from the current file.

        Args:
            flags : Specify which selectables to return 'FIDS' and/or 'NAMES';
                    If not specified, all selectables will be returned.
        Returns:
            dict containing all selectable items. Key is identifier (string), value
            a reference to a CardFile (or derived class) instance.
        """
        sels = {}
        # we can always select ourself
        if flags == [] or 'SELF' in flags:
            sels = self._get_self_selectables('.', flags)
        # we can always select our parent
        if flags == [] or 'PARENT' in flags:
            if self.parent:
                sels = self.parent._get_self_selectables('..', flags)
        # if we have a MF, we can always select its applications
        if flags == [] or 'MF' in flags:
            mf = self.get_mf()
            if mf:
                sels.update(mf._get_self_selectables(flags=flags))
                sels.update(mf.get_app_selectables(flags=flags))
        return sels

    def get_selectable_names(self, flags=[]) -> List[str]:
        """Return a dict of {'identifier': File} that is selectable from the current file.

        Args:
            flags : Specify which selectables to return 'FIDS' and/or 'NAMES';
                    If not specified, all selectables will be returned.
        Returns:
            list containing all selectable names.
        """
        sels = self.get_selectables(flags)
        sel_keys = list(sels.keys())
        sel_keys.sort()
        return sel_keys

    def decode_select_response(self, data_hex: str):
        """Decode the response to a SELECT command.

        Args:
            data_hex: Hex string of the select response
        """

        # When the current file does not implement a custom select response decoder,
        # we just ask the parent file to decode the select response. If this method
        # is not overloaded by the current file we will again ask the parent file.
        # This way we recursively travel up the file system tree until we hit a file
        # that does implement a concrete decoder.
        if self.parent:
            return self.parent.decode_select_response(data_hex)

    def get_profile(self):
        """Get the profile associated with this file. If this file does not have any
        profile assigned, try to find a file above (usually the MF) in the filesystem
        hirarchy that has a profile assigned
        """

        # If we have a profile set, return it
        if self.profile:
            return self.profile

        # Walk up recursively until we hit a parent that has a profile set
        if self.parent:
            return self.parent.get_profile()
        return None

    def should_exist_for_services(self, services: List[int]):
        """Assuming the provided list of activated services, should this file exist and be activated?."""
        if self.service is None:
            return None
        elif isinstance(self.service, int):
            # a single service determines the result
            return self.service in services
        elif isinstance(self.service, list):
            # any of the services active -> true
            for s in self.service:
                if s in services:
                    return True
            return False
        elif isinstance(self.service, tuple):
            # all of the services active -> true
            for s in self.service:
                if not s in services:
                    return False
            return True
        else:
            raise ValueError("self.service must be either int or list or tuple")


class CardDF(CardFile):
    """DF (Dedicated File) in the smart card filesystem.  Those are basically sub-directories."""

    @with_default_category('DF/ADF Commands')
    class ShellCommands(CommandSet):
        def __init__(self):
            super().__init__()

    def __init__(self, **kwargs):
        if not isinstance(self, CardADF):
            if not 'fid' in kwargs:
                raise TypeError('fid is mandatory for all DF')
        super().__init__(**kwargs)
        self.children = dict()
        self.shell_commands = [self.ShellCommands()]
        # dict of CardFile affected by service(int), indexed by service
        self.files_by_service = {}

    def __str__(self):
        return "DF(%s)" % (super().__str__())

    def _add_file_services(self, child):
        """Add a child (DF/EF) to the files_by_services of the parent."""
        if not child.service:
            return
        if isinstance(child.service, int):
            self.files_by_service.setdefault(child.service, []).append(child)
        elif isinstance(child.service, list):
            for service in child.service:
                self.files_by_service.setdefault(service, []).append(child)
        elif isinstance(child.service, tuple):
            for service in child.service:
                self.files_by_service.setdefault(service, []).append(child)
        else:
            raise ValueError

    def _has_service(self):
        if self.service:
            return True
        for c in self.children.values():
            if isinstance(c, CardDF):
                if c._has_service():
                    return True

    def add_file(self, child: CardFile, ignore_existing: bool = False):
        """Add a child (DF/EF) to this DF.
        Args:
            child: The new DF/EF to be added
            ignore_existing: Ignore, if file with given FID already exists. Old one will be kept.
        """
        if not isinstance(child, CardFile):
            raise TypeError("Expected a File instance")
        if not is_hex(child.fid, minlen=4, maxlen=4):
            raise ValueError("File name %s is not a valid fid" % (child.fid))
        if child.name in CardFile.RESERVED_NAMES:
            raise ValueError("File name %s is a reserved name" % (child.name))
        if child.fid in CardFile.RESERVED_FIDS:
            raise ValueError("File fid %s is a reserved fid" % (child.fid))
        if child.fid in self.children:
            if ignore_existing:
                return
            raise ValueError(
                "File with given fid %s already exists in %s" % (child.fid, self))
        if self.lookup_file_by_sfid(child.sfid):
            raise ValueError(
                "File with given sfid %s already exists in %s" % (child.sfid, self))
        if self.lookup_file_by_name(child.name):
            if ignore_existing:
                return
            raise ValueError(
                "File with given name %s already exists in %s" % (child.name, self))
        self.children[child.fid] = child
        child.parent = self
        # update the service -> file relationship table
        self._add_file_services(child)
        if isinstance(child, CardDF):
            for c in child.children.values():
                self._add_file_services(c)
                if isinstance(c, CardDF):
                    for gc in c.children.values():
                        if isinstance(gc, CardDF):
                            if gc._has_service():
                                raise ValueError('TODO: implement recursive service -> file mapping')

    def add_files(self, children: Iterable[CardFile], ignore_existing: bool = False):
        """Add a list of child (DF/EF) to this DF

        Args:
            children: List of new DF/EFs to be added
            ignore_existing: Ignore, if file[s] with given FID already exists. Old one[s] will be kept.
        """
        for child in children:
            self.add_file(child, ignore_existing)

    def get_selectables(self, flags=[]) -> dict:
        """Return a dict of {'identifier': File} that is selectable from the current DF.

        Args:
            flags : Specify which selectables to return 'FIDS' and/or 'NAMES';
                    If not specified, all selectables will be returned.
        Returns:
            dict containing all selectable items. Key is identifier (string), value
            a reference to a CardFile (or derived class) instance.
        """
        # global selectables + our children
        sels = super().get_selectables(flags)
        if flags == [] or 'FIDS' in flags:
            sels.update({x.fid: x for x in self.children.values() if x.fid})
        if flags == [] or 'FNAMES' in flags:
            sels.update({x.name: x for x in self.children.values() if x.name})
        return sels

    def lookup_file_by_name(self, name: Optional[str]) -> Optional[CardFile]:
        """Find a file with given name within current DF."""
        if name == None:
            return None
        for i in self.children.values():
            if i.name and i.name == name:
                return i
        return None

    def lookup_file_by_sfid(self, sfid: Optional[str]) -> Optional[CardFile]:
        """Find a file with given short file ID within current DF."""
        if sfid == None:
            return None
        for i in self.children.values():
            if i.sfid == int(str(sfid)):
                return i
        return None

    def lookup_file_by_fid(self, fid: str) -> Optional[CardFile]:
        """Find a file with given file ID within current DF."""
        if fid in self.children:
            return self.children[fid]
        return None


class CardMF(CardDF):
    """MF (Master File) in the smart card filesystem"""

    def __init__(self, **kwargs):
        # can be overridden; use setdefault
        kwargs.setdefault('fid', '3f00')
        kwargs.setdefault('name', 'MF')
        kwargs.setdefault('desc', 'Master File (directory root)')
        # cannot be overridden; use assignment
        kwargs['parent'] = self
        super().__init__(**kwargs)
        self.applications = dict()

    def __str__(self):
        return "MF(%s)" % (self.fid)

    def add_application_df(self, app: 'CardADF'):
        """Add an Application to the MF"""
        if not isinstance(app, CardADF):
            raise TypeError("Expected an ADF instance")
        if app.aid in self.applications:
            raise ValueError("AID %s already exists" % (app.aid))
        self.applications[app.aid] = app
        app.parent = self

    def get_app_names(self):
        """Get list of completions (AID names)"""
        return list(self.applications.values())

    def get_selectables(self, flags=[]) -> dict:
        """Return a dict of {'identifier': File} that is selectable from the current DF.

        Args:
            flags : Specify which selectables to return 'FIDS' and/or 'NAMES';
                    If not specified, all selectables will be returned.
        Returns:
            dict containing all selectable items. Key is identifier (string), value
            a reference to a CardFile (or derived class) instance.
        """
        sels = super().get_selectables(flags)
        sels.update(self.get_app_selectables(flags))
        return sels

    def get_app_selectables(self, flags=[]) -> dict:
        """Get applications by AID + name"""
        sels = {}
        if flags == [] or 'AIDS' in flags:
            sels.update({x.aid: x for x in self.applications.values()})
        if flags == [] or 'ANAMES' in flags:
            sels.update(
                {x.name: x for x in self.applications.values() if x.name})
        return sels

    def decode_select_response(self, data_hex: Optional[str]) -> object:
        """Decode the response to a SELECT command.

        This is the fall-back method which automatically defers to the standard decoding
        method defined by the card profile. When no profile is set, then no decoding is
        performed. Specific derived classes (usually ADF) can overload this method to
        install specific decoding.
        """

        if not data_hex:
            return data_hex

        profile = self.get_profile()

        if profile:
            return profile.decode_select_response(data_hex)
        else:
            return data_hex


class CardADF(CardDF):
    """ADF (Application Dedicated File) in the smart card filesystem"""

    def __init__(self, aid: str, **kwargs):
        super().__init__(**kwargs)
        # reference to CardApplication may be set from CardApplication constructor
        self.application = None  # type: Optional[CardApplication]
        self.aid = aid           # Application Identifier
        mf = self.get_mf()
        if mf:
            mf.add_application_df(self)

    def __str__(self):
        return "ADF(%s)" % (self.name if self.name else self.aid)

    def _path_element(self, prefer_name: bool):
        if self.name and prefer_name:
            return self.name
        else:
            return self.aid


class CardEF(CardFile):
    """EF (Entry File) in the smart card filesystem"""

    def __init__(self, *, fid, **kwargs):
        kwargs['fid'] = fid
        super().__init__(**kwargs)

    def __str__(self):
        return "EF(%s)" % (super().__str__())

    def get_selectables(self, flags=[]) -> dict:
        """Return a dict of {'identifier': File} that is selectable from the current DF.

        Args:
            flags : Specify which selectables to return 'FIDS' and/or 'NAMES';
                    If not specified, all selectables will be returned.
        Returns:
            dict containing all selectable items. Key is identifier (string), value
            a reference to a CardFile (or derived class) instance.
        """
        # global selectable names + those of the parent DF
        sels = super().get_selectables(flags)
        sels.update(
            {x.name: x for x in self.parent.children.values() if x != self})
        return sels


class TransparentEF(CardEF):
    """Transparent EF (Entry File) in the smart card filesystem.

    A Transparent EF is a binary file with no formal structure.  This is contrary to
    Record based EFs which have [fixed size] records that can be individually read/updated."""

    @with_default_category('Transparent EF Commands')
    class ShellCommands(CommandSet):
        """Shell commands specific for transparent EFs."""

        def __init__(self):
            super().__init__()

        dec_hex_parser = argparse.ArgumentParser()
        dec_hex_parser.add_argument('--oneline', action='store_true',
                                    help='No JSON pretty-printing, dump as a single line')
        dec_hex_parser.add_argument('HEXSTR', help='Hex-string of encoded data to decode')

        @cmd2.with_argparser(dec_hex_parser)
        def do_decode_hex(self, opts):
            """Decode command-line provided hex-string as if it was read from the file."""
            data = self._cmd.lchan.selected_file.decode_hex(opts.HEXSTR)
            self._cmd.poutput_json(data, opts.oneline)

        read_bin_parser = argparse.ArgumentParser()
        read_bin_parser.add_argument(
            '--offset', type=int, default=0, help='Byte offset for start of read')
        read_bin_parser.add_argument(
            '--length', type=int, help='Number of bytes to read')

        @cmd2.with_argparser(read_bin_parser)
        def do_read_binary(self, opts):
            """Read binary data from a transparent EF"""
            (data, sw) = self._cmd.lchan.read_binary(opts.length, opts.offset)
            self._cmd.poutput(data)

        read_bin_dec_parser = argparse.ArgumentParser()
        read_bin_dec_parser.add_argument('--oneline', action='store_true',
                                         help='No JSON pretty-printing, dump as a single line')

        @cmd2.with_argparser(read_bin_dec_parser)
        def do_read_binary_decoded(self, opts):
            """Read + decode data from a transparent EF"""
            (data, sw) = self._cmd.lchan.read_binary_dec()
            self._cmd.poutput_json(data, opts.oneline)

        upd_bin_parser = argparse.ArgumentParser()
        upd_bin_parser.add_argument(
            '--offset', type=int, default=0, help='Byte offset for start of read')
        upd_bin_parser.add_argument(
            'data', help='Data bytes (hex format) to write')

        @cmd2.with_argparser(upd_bin_parser)
        def do_update_binary(self, opts):
            """Update (Write) data of a transparent EF"""
            (data, sw) = self._cmd.lchan.update_binary(opts.data, opts.offset)
            if data:
                self._cmd.poutput(data)

        upd_bin_dec_parser = argparse.ArgumentParser()
        upd_bin_dec_parser.add_argument(
            'data', help='Abstract data (JSON format) to write')
        upd_bin_dec_parser.add_argument('--json-path', type=str,
                                        help='JSON path to modify specific element of file only')

        @cmd2.with_argparser(upd_bin_dec_parser)
        def do_update_binary_decoded(self, opts):
            """Encode + Update (Write) data of a transparent EF"""
            if opts.json_path:
                (data_json, sw) = self._cmd.lchan.read_binary_dec()
                js_path_modify(data_json, opts.json_path,
                               json.loads(opts.data))
            else:
                data_json = json.loads(opts.data)
            (data, sw) = self._cmd.lchan.update_binary_dec(data_json)
            if data:
                self._cmd.poutput_json(data)

        def do_edit_binary_decoded(self, opts):
            """Edit the JSON representation of the EF contents in an editor."""
            (orig_json, sw) = self._cmd.lchan.read_binary_dec()
            with tempfile.TemporaryDirectory(prefix='pysim_') as dirname:
                filename = '%s/file' % dirname
                # write existing data as JSON to file
                with open(filename, 'w') as text_file:
                    json.dump(orig_json, text_file, indent=4)
                # run a text editor
                self._cmd._run_editor(filename)
                with open(filename, 'r') as text_file:
                    edited_json = json.load(text_file)
                if edited_json == orig_json:
                    self._cmd.poutput("Data not modified, skipping write")
                else:
                    (data, sw) = self._cmd.lchan.update_binary_dec(edited_json)
                    if data:
                        self._cmd.poutput_json(data)

    def __init__(self, fid: str, sfid: str = None, name: str = None, desc: str = None, parent: CardDF = None,
                 size={1, None}, **kwargs):
        """
        Args:
            fid : File Identifier (4 hex digits)
            sfid : Short File Identifier (2 hex digits, optional)
            name : Brief name of the file, lik EF_ICCID
            desc : Description of the file
            parent : Parent CardFile object within filesystem hierarchy
            size : tuple of (minimum_size, recommended_size)
        """
        super().__init__(fid=fid, sfid=sfid, name=name, desc=desc, parent=parent, **kwargs)
        self._construct = None
        self._tlv = None
        self.size = size
        self.shell_commands = [self.ShellCommands()]

    def decode_bin(self, raw_bin_data: bytearray) -> dict:
        """Decode raw (binary) data into abstract representation.

        A derived class would typically provide a _decode_bin() or _decode_hex() method
        for implementing this specifically for the given file. This function checks which
        of the method exists, add calls them (with conversion, as needed).

        Args:
            raw_bin_data : binary encoded data
        Returns:
            abstract_data; dict representing the decoded data
        """
        method = getattr(self, '_decode_bin', None)
        if callable(method):
            return method(raw_bin_data)
        method = getattr(self, '_decode_hex', None)
        if callable(method):
            return method(b2h(raw_bin_data))
        if self._construct:
            return parse_construct(self._construct, raw_bin_data)
        elif self._tlv:
            t = self._tlv() if inspect.isclass(self._tlv) else self._tlv
            t.from_tlv(raw_bin_data)
            return t.to_dict()
        return {'raw': raw_bin_data.hex()}

    def decode_hex(self, raw_hex_data: str) -> dict:
        """Decode raw (hex string) data into abstract representation.

        A derived class would typically provide a _decode_bin() or _decode_hex() method
        for implementing this specifically for the given file. This function checks which
        of the method exists, add calls them (with conversion, as needed).

        Args:
            raw_hex_data : hex-encoded data
        Returns:
            abstract_data; dict representing the decoded data
        """
        method = getattr(self, '_decode_hex', None)
        if callable(method):
            return method(raw_hex_data)
        raw_bin_data = h2b(raw_hex_data)
        method = getattr(self, '_decode_bin', None)
        if callable(method):
            return method(raw_bin_data)
        if self._construct:
            return parse_construct(self._construct, raw_bin_data)
        elif self._tlv:
            t = self._tlv() if inspect.isclass(self._tlv) else self._tlv
            t.from_tlv(raw_bin_data)
            return t.to_dict()
        return {'raw': raw_bin_data.hex()}

    def encode_bin(self, abstract_data: dict) -> bytearray:
        """Encode abstract representation into raw (binary) data.

        A derived class would typically provide an _encode_bin() or _encode_hex() method
        for implementing this specifically for the given file. This function checks which
        of the method exists, add calls them (with conversion, as needed).

        Args:
            abstract_data : dict representing the decoded data
        Returns:
            binary encoded data
        """
        method = getattr(self, '_encode_bin', None)
        if callable(method):
            return method(abstract_data)
        method = getattr(self, '_encode_hex', None)
        if callable(method):
            return h2b(method(abstract_data))
        if self._construct:
            return self._construct.build(abstract_data)
        elif self._tlv:
            t = self._tlv() if inspect.isclass(self._tlv) else self._tlv
            t.from_dict(abstract_data)
            return t.to_tlv()
        raise NotImplementedError(
            "%s encoder not yet implemented. Patches welcome." % self)

    def encode_hex(self, abstract_data: dict) -> str:
        """Encode abstract representation into raw (hex string) data.

        A derived class would typically provide an _encode_bin() or _encode_hex() method
        for implementing this specifically for the given file. This function checks which
        of the method exists, add calls them (with conversion, as needed).

        Args:
            abstract_data : dict representing the decoded data
        Returns:
            hex string encoded data
        """
        method = getattr(self, '_encode_hex', None)
        if callable(method):
            return method(abstract_data)
        method = getattr(self, '_encode_bin', None)
        if callable(method):
            raw_bin_data = method(abstract_data)
            return b2h(raw_bin_data)
        if self._construct:
            return b2h(self._construct.build(abstract_data))
        elif self._tlv:
            t = self._tlv() if inspect.isclass(self._tlv) else self._tlv
            t.from_dict(abstract_data)
            return b2h(t.to_tlv())
        raise NotImplementedError(
            "%s encoder not yet implemented. Patches welcome." % self)


class LinFixedEF(CardEF):
    """Linear Fixed EF (Entry File) in the smart card filesystem.

    Linear Fixed EFs are record oriented files.  They consist of a number of fixed-size
    records.  The records can be individually read/updated."""

    @with_default_category('Linear Fixed EF Commands')
    class ShellCommands(CommandSet):
        """Shell commands specific for Linear Fixed EFs."""

        def __init__(self, **kwargs):
            super().__init__(**kwargs)

        dec_hex_parser = argparse.ArgumentParser()
        dec_hex_parser.add_argument('--oneline', action='store_true',
                                    help='No JSON pretty-printing, dump as a single line')
        dec_hex_parser.add_argument('HEXSTR', help='Hex-string of encoded data to decode')

        @cmd2.with_argparser(dec_hex_parser)
        def do_decode_hex(self, opts):
            """Decode command-line provided hex-string as if it was read from the file."""
            data = self._cmd.lchan.selected_file.decode_record_hex(opts.HEXSTR)
            self._cmd.poutput_json(data, opts.oneline)

        read_rec_parser = argparse.ArgumentParser()
        read_rec_parser.add_argument(
            'record_nr', type=int, help='Number of record to be read')
        read_rec_parser.add_argument(
            '--count', type=int, default=1, help='Number of records to be read, beginning at record_nr')

        @cmd2.with_argparser(read_rec_parser)
        def do_read_record(self, opts):
            """Read one or multiple records from a record-oriented EF"""
            for r in range(opts.count):
                recnr = opts.record_nr + r
                (data, sw) = self._cmd.lchan.read_record(recnr)
                if (len(data) > 0):
                    recstr = str(data)
                else:
                    recstr = "(empty)"
                self._cmd.poutput("%03d %s" % (recnr, recstr))

        read_rec_dec_parser = argparse.ArgumentParser()
        read_rec_dec_parser.add_argument(
            'record_nr', type=int, help='Number of record to be read')
        read_rec_dec_parser.add_argument('--oneline', action='store_true',
                                         help='No JSON pretty-printing, dump as a single line')

        @cmd2.with_argparser(read_rec_dec_parser)
        def do_read_record_decoded(self, opts):
            """Read + decode a record from a record-oriented EF"""
            (data, sw) = self._cmd.lchan.read_record_dec(opts.record_nr)
            self._cmd.poutput_json(data, opts.oneline)

        read_recs_parser = argparse.ArgumentParser()

        @cmd2.with_argparser(read_recs_parser)
        def do_read_records(self, opts):
            """Read all records from a record-oriented EF"""
            num_of_rec = self._cmd.lchan.selected_file_num_of_rec()
            for recnr in range(1, 1 + num_of_rec):
                (data, sw) = self._cmd.lchan.read_record(recnr)
                if (len(data) > 0):
                    recstr = str(data)
                else:
                    recstr = "(empty)"
                self._cmd.poutput("%03d %s" % (recnr, recstr))

        read_recs_dec_parser = argparse.ArgumentParser()
        read_recs_dec_parser.add_argument('--oneline', action='store_true',
                                          help='No JSON pretty-printing, dump as a single line')

        @cmd2.with_argparser(read_recs_dec_parser)
        def do_read_records_decoded(self, opts):
            """Read + decode all records from a record-oriented EF"""
            num_of_rec = self._cmd.lchan.selected_file_num_of_rec()
            # collect all results in list so they are rendered as JSON list when printing
            data_list = []
            for recnr in range(1, 1 + num_of_rec):
                (data, sw) = self._cmd.lchan.read_record_dec(recnr)
                data_list.append(data)
            self._cmd.poutput_json(data_list, opts.oneline)

        upd_rec_parser = argparse.ArgumentParser()
        upd_rec_parser.add_argument(
            'record_nr', type=int, help='Number of record to be read')
        upd_rec_parser.add_argument(
            'data', help='Data bytes (hex format) to write')

        @cmd2.with_argparser(upd_rec_parser)
        def do_update_record(self, opts):
            """Update (write) data to a record-oriented EF"""
            (data, sw) = self._cmd.lchan.update_record(opts.record_nr, opts.data)
            if data:
                self._cmd.poutput(data)

        upd_rec_dec_parser = argparse.ArgumentParser()
        upd_rec_dec_parser.add_argument(
            'record_nr', type=int, help='Number of record to be read')
        upd_rec_dec_parser.add_argument(
            'data', help='Abstract data (JSON format) to write')
        upd_rec_dec_parser.add_argument('--json-path', type=str,
                                        help='JSON path to modify specific element of record only')

        @cmd2.with_argparser(upd_rec_dec_parser)
        def do_update_record_decoded(self, opts):
            """Encode + Update (write) data to a record-oriented EF"""
            if opts.json_path:
                (data_json, sw) = self._cmd.lchan.read_record_dec(opts.record_nr)
                js_path_modify(data_json, opts.json_path,
                               json.loads(opts.data))
            else:
                data_json = json.loads(opts.data)
            (data, sw) = self._cmd.lchan.update_record_dec(
                opts.record_nr, data_json)
            if data:
                self._cmd.poutput(data)

        edit_rec_dec_parser = argparse.ArgumentParser()
        edit_rec_dec_parser.add_argument(
            'record_nr', type=int, help='Number of record to be edited')

        @cmd2.with_argparser(edit_rec_dec_parser)
        def do_edit_record_decoded(self, opts):
            """Edit the JSON representation of one record in an editor."""
            (orig_json, sw) = self._cmd.lchan.read_record_dec(opts.record_nr)
            with tempfile.TemporaryDirectory(prefix='pysim_') as dirname:
                filename = '%s/file' % dirname
                # write existing data as JSON to file
                with open(filename, 'w') as text_file:
                    json.dump(orig_json, text_file, indent=4)
                # run a text editor
                self._cmd._run_editor(filename)
                with open(filename, 'r') as text_file:
                    edited_json = json.load(text_file)
                if edited_json == orig_json:
                    self._cmd.poutput("Data not modified, skipping write")
                else:
                    (data, sw) = self._cmd.lchan.update_record_dec(
                        opts.record_nr, edited_json)
                    if data:
                        self._cmd.poutput_json(data)

    def __init__(self, fid: str, sfid: str = None, name: str = None, desc: str = None,
                 parent: Optional[CardDF] = None, rec_len={1, None}, **kwargs):
        """
        Args:
            fid : File Identifier (4 hex digits)
            sfid : Short File Identifier (2 hex digits, optional)
            name : Brief name of the file, lik EF_ICCID
            desc : Description of the file
            parent : Parent CardFile object within filesystem hierarchy
            rec_len : set of {minimum_length, recommended_length}
        """
        super().__init__(fid=fid, sfid=sfid, name=name, desc=desc, parent=parent, **kwargs)
        self.rec_len = rec_len
        self.shell_commands = [self.ShellCommands()]
        self._construct = None
        self._tlv = None

    def decode_record_hex(self, raw_hex_data: str) -> dict:
        """Decode raw (hex string) data into abstract representation.

        A derived class would typically provide a _decode_record_bin() or _decode_record_hex()
        method for implementing this specifically for the given file. This function checks which
        of the method exists, add calls them (with conversion, as needed).

        Args:
            raw_hex_data : hex-encoded data
        Returns:
            abstract_data; dict representing the decoded data
        """
        method = getattr(self, '_decode_record_hex', None)
        if callable(method):
            return method(raw_hex_data)
        raw_bin_data = h2b(raw_hex_data)
        method = getattr(self, '_decode_record_bin', None)
        if callable(method):
            return method(raw_bin_data)
        if self._construct:
            return parse_construct(self._construct, raw_bin_data)
        elif self._tlv:
            t = self._tlv() if inspect.isclass(self._tlv) else self._tlv
            t.from_tlv(raw_bin_data)
            return t.to_dict()
        return {'raw': raw_bin_data.hex()}

    def decode_record_bin(self, raw_bin_data: bytearray) -> dict:
        """Decode raw (binary) data into abstract representation.

        A derived class would typically provide a _decode_record_bin() or _decode_record_hex()
        method for implementing this specifically for the given file. This function checks which
        of the method exists, add calls them (with conversion, as needed).

        Args:
            raw_bin_data : binary encoded data
        Returns:
            abstract_data; dict representing the decoded data
        """
        method = getattr(self, '_decode_record_bin', None)
        if callable(method):
            return method(raw_bin_data)
        raw_hex_data = b2h(raw_bin_data)
        method = getattr(self, '_decode_record_hex', None)
        if callable(method):
            return method(raw_hex_data)
        if self._construct:
            return parse_construct(self._construct, raw_bin_data)
        elif self._tlv:
            t = self._tlv() if inspect.isclass(self._tlv) else self._tlv
            t.from_tlv(raw_bin_data)
            return t.to_dict()
        return {'raw': raw_hex_data}

    def encode_record_hex(self, abstract_data: dict) -> str:
        """Encode abstract representation into raw (hex string) data.

        A derived class would typically provide an _encode_record_bin() or _encode_record_hex()
        method for implementing this specifically for the given file. This function checks which
        of the method exists, add calls them (with conversion, as needed).

        Args:
            abstract_data : dict representing the decoded data
        Returns:
            hex string encoded data
        """
        method = getattr(self, '_encode_record_hex', None)
        if callable(method):
            return method(abstract_data)
        method = getattr(self, '_encode_record_bin', None)
        if callable(method):
            raw_bin_data = method(abstract_data)
            return b2h(raw_bin_data)
        if self._construct:
            return b2h(self._construct.build(abstract_data))
        elif self._tlv:
            t = self._tlv() if inspect.isclass(self._tlv) else self._tlv
            t.from_dict(abstract_data)
            return b2h(t.to_tlv())
        raise NotImplementedError(
            "%s encoder not yet implemented. Patches welcome." % self)

    def encode_record_bin(self, abstract_data: dict) -> bytearray:
        """Encode abstract representation into raw (binary) data.

        A derived class would typically provide an _encode_record_bin() or _encode_record_hex()
        method for implementing this specifically for the given file. This function checks which
        of the method exists, add calls them (with conversion, as needed).

        Args:
            abstract_data : dict representing the decoded data
        Returns:
            binary encoded data
        """
        method = getattr(self, '_encode_record_bin', None)
        if callable(method):
            return method(abstract_data)
        method = getattr(self, '_encode_record_hex', None)
        if callable(method):
            return h2b(method(abstract_data))
        if self._construct:
            return self._construct.build(abstract_data)
        elif self._tlv:
            t = self._tlv() if inspect.isclass(self._tlv) else self._tlv
            t.from_dict(abstract_data)
            return t.to_tlv()
        raise NotImplementedError(
            "%s encoder not yet implemented. Patches welcome." % self)


class CyclicEF(LinFixedEF):
    """Cyclic EF (Entry File) in the smart card filesystem"""
    # we don't really have any special support for those; just recycling LinFixedEF here

    def __init__(self, fid: str, sfid: str = None, name: str = None, desc: str = None, parent: CardDF = None,
                 rec_len={1, None}, **kwargs):
        super().__init__(fid=fid, sfid=sfid, name=name, desc=desc, parent=parent, rec_len=rec_len, **kwargs)


class TransRecEF(TransparentEF):
    """Transparent EF (Entry File) containing fixed-size records.

    These are the real odd-balls and mostly look like mistakes in the specification:
    Specified as 'transparent' EF, but actually containing several fixed-length records
    inside.
    We add a special class for those, so the user only has to provide encoder/decoder functions
    for a record, while this class takes care of split / merge of records.
    """

    def __init__(self, fid: str, rec_len: int, sfid: str = None, name: str = None, desc: str = None,
                 parent: Optional[CardDF] = None, size={1, None}, **kwargs):
        """
        Args:
            fid : File Identifier (4 hex digits)
            sfid : Short File Identifier (2 hex digits, optional)
            name : Brief name of the file, like EF_ICCID
            desc : Description of the file
            parent : Parent CardFile object within filesystem hierarchy
            rec_len : Length of the fixed-length records within transparent EF
            size : tuple of (minimum_size, recommended_size)
        """
        super().__init__(fid=fid, sfid=sfid, name=name, desc=desc, parent=parent, size=size, **kwargs)
        self.rec_len = rec_len

    def decode_record_hex(self, raw_hex_data: str) -> dict:
        """Decode raw (hex string) data into abstract representation.

        A derived class would typically provide a _decode_record_bin() or _decode_record_hex()
        method for implementing this specifically for the given file. This function checks which
        of the method exists, add calls them (with conversion, as needed).

        Args:
            raw_hex_data : hex-encoded data
        Returns:
            abstract_data; dict representing the decoded data
        """
        method = getattr(self, '_decode_record_hex', None)
        if callable(method):
            return method(raw_hex_data)
        raw_bin_data = h2b(raw_hex_data)
        method = getattr(self, '_decode_record_bin', None)
        if callable(method):
            return method(raw_bin_data)
        if self._construct:
            return parse_construct(self._construct, raw_bin_data)
        elif self._tlv:
            t = self._tlv() if inspect.isclass(self._tlv) else self._tlv
            t.from_tlv(raw_bin_data)
            return t.to_dict()
        return {'raw': raw_hex_data}

    def decode_record_bin(self, raw_bin_data: bytearray) -> dict:
        """Decode raw (binary) data into abstract representation.

        A derived class would typically provide a _decode_record_bin() or _decode_record_hex()
        method for implementing this specifically for the given file. This function checks which
        of the method exists, add calls them (with conversion, as needed).

        Args:
            raw_bin_data : binary encoded data
        Returns:
            abstract_data; dict representing the decoded data
        """
        method = getattr(self, '_decode_record_bin', None)
        if callable(method):
            return method(raw_bin_data)
        raw_hex_data = b2h(raw_bin_data)
        method = getattr(self, '_decode_record_hex', None)
        if callable(method):
            return method(raw_hex_data)
        if self._construct:
            return parse_construct(self._construct, raw_bin_data)
        elif self._tlv:
            t = self._tlv() if inspect.isclass(self._tlv) else self._tlv
            t.from_tlv(raw_bin_data)
            return t.to_dict()
        return {'raw': raw_hex_data}

    def encode_record_hex(self, abstract_data: dict) -> str:
        """Encode abstract representation into raw (hex string) data.

        A derived class would typically provide an _encode_record_bin() or _encode_record_hex()
        method for implementing this specifically for the given file. This function checks which
        of the method exists, add calls them (with conversion, as needed).

        Args:
            abstract_data : dict representing the decoded data
        Returns:
            hex string encoded data
        """
        method = getattr(self, '_encode_record_hex', None)
        if callable(method):
            return method(abstract_data)
        method = getattr(self, '_encode_record_bin', None)
        if callable(method):
            return b2h(method(abstract_data))
        if self._construct:
            return b2h(filter_dict(self._construct.build(abstract_data)))
        elif self._tlv:
            t = self._tlv() if inspect.isclass(self._tlv) else self._tlv
            t.from_dict(abstract_data)
            return b2h(t.to_tlv())
        raise NotImplementedError(
            "%s encoder not yet implemented. Patches welcome." % self)

    def encode_record_bin(self, abstract_data: dict) -> bytearray:
        """Encode abstract representation into raw (binary) data.

        A derived class would typically provide an _encode_record_bin() or _encode_record_hex()
        method for implementing this specifically for the given file. This function checks which
        of the method exists, add calls them (with conversion, as needed).

        Args:
            abstract_data : dict representing the decoded data
        Returns:
            binary encoded data
        """
        method = getattr(self, '_encode_record_bin', None)
        if callable(method):
            return method(abstract_data)
        method = getattr(self, '_encode_record_hex', None)
        if callable(method):
            return h2b(method(abstract_data))
        if self._construct:
            return filter_dict(self._construct.build(abstract_data))
        elif self._tlv:
            t = self._tlv() if inspect.isclass(self._tlv) else self._tlv
            t.from_dict(abstract_data)
            return t.to_tlv()
        raise NotImplementedError(
            "%s encoder not yet implemented. Patches welcome." % self)

    def _decode_bin(self, raw_bin_data: bytearray):
        chunks = [raw_bin_data[i:i+self.rec_len]
                  for i in range(0, len(raw_bin_data), self.rec_len)]
        return [self.decode_record_bin(x) for x in chunks]

    def _encode_bin(self, abstract_data) -> bytes:
        chunks = [self.encode_record_bin(x) for x in abstract_data]
        # FIXME: pad to file size
        return b''.join(chunks)


class BerTlvEF(CardEF):
    """BER-TLV EF (Entry File) in the smart card filesystem.
    A BER-TLV EF is a binary file with a BER (Basic Encoding Rules) TLV structure

    NOTE: We currently don't really support those, this class is simply a wrapper
    around TransparentEF as a place-holder, so we can already define EFs of BER-TLV
    type without fully supporting them."""

    @with_default_category('BER-TLV EF Commands')
    class ShellCommands(CommandSet):
        """Shell commands specific for BER-TLV EFs."""

        def __init__(self):
            super().__init__()

        retrieve_data_parser = argparse.ArgumentParser()
        retrieve_data_parser.add_argument(
            'tag', type=auto_int, help='BER-TLV Tag of value to retrieve')

        @cmd2.with_argparser(retrieve_data_parser)
        def do_retrieve_data(self, opts):
            """Retrieve (Read) data from a BER-TLV EF"""
            (data, sw) = self._cmd.lchan.retrieve_data(opts.tag)
            self._cmd.poutput(data)

        def do_retrieve_tags(self, opts):
            """List tags available in a given BER-TLV EF"""
            tags = self._cmd.lchan.retrieve_tags()
            self._cmd.poutput(tags)

        set_data_parser = argparse.ArgumentParser()
        set_data_parser.add_argument(
            'tag', type=auto_int, help='BER-TLV Tag of value to set')
        set_data_parser.add_argument(
            'data', help='Data bytes (hex format) to write')

        @cmd2.with_argparser(set_data_parser)
        def do_set_data(self, opts):
            """Set (Write) data for a given tag in a BER-TLV EF"""
            (data, sw) = self._cmd.lchan.set_data(opts.tag, opts.data)
            if data:
                self._cmd.poutput(data)

        del_data_parser = argparse.ArgumentParser()
        del_data_parser.add_argument(
            'tag', type=auto_int, help='BER-TLV Tag of value to set')

        @cmd2.with_argparser(del_data_parser)
        def do_delete_data(self, opts):
            """Delete  data for a given tag in a BER-TLV EF"""
            (data, sw) = self._cmd.lchan.set_data(opts.tag, None)
            if data:
                self._cmd.poutput(data)

    def __init__(self, fid: str, sfid: str = None, name: str = None, desc: str = None, parent: CardDF = None,
                 size={1, None}, **kwargs):
        """
        Args:
            fid : File Identifier (4 hex digits)
            sfid : Short File Identifier (2 hex digits, optional)
            name : Brief name of the file, lik EF_ICCID
            desc : Description of the file
            parent : Parent CardFile object within filesystem hierarchy
            size : tuple of (minimum_size, recommended_size)
        """
        super().__init__(fid=fid, sfid=sfid, name=name, desc=desc, parent=parent, **kwargs)
        self._construct = None
        self.size = size
        self.shell_commands = [self.ShellCommands()]


class RuntimeState:
    """Represent the runtime state of a session with a card."""

    def __init__(self, card, profile: 'CardProfile'):
        """
        Args:
            card : pysim.cards.Card instance
            profile : CardProfile instance
        """
        self.mf = CardMF(profile=profile)
        self.card = card
        self.profile = profile
        self.lchan = {}
        # the basic logical channel always exists
        self.lchan[0] = RuntimeLchan(0, self)

        # make sure the class and selection control bytes, which are specified
        # by the card profile are used
        self.card.set_apdu_parameter(
            cla=self.profile.cla, sel_ctrl=self.profile.sel_ctrl)

        # add application ADFs + MF-files from profile
        apps = self._match_applications()
        for a in apps:
            if a.adf:
                self.mf.add_application_df(a.adf)
        for f in self.profile.files_in_mf:
            self.mf.add_file(f)
        self.conserve_write = True

        # make sure that when the runtime state is created, the card is also
        # in a defined state.
        self.reset()

    def _match_applications(self):
        """match the applications from the profile with applications on the card"""
        apps_profile = self.profile.applications

        # When the profile does not feature any applications, then we are done already
        if not apps_profile:
            return []

        # Read AIDs from card and match them against the applications defined by the
        # card profile
        aids_card = self.card.read_aids()
        apps_taken = []
        if aids_card:
            aids_taken = []
            print("AIDs on card:")
            for a in aids_card:
                for f in apps_profile:
                    if f.aid in a:
                        print(" %s: %s (EF.DIR)" % (f.name, a))
                        aids_taken.append(a)
                        apps_taken.append(f)
            aids_unknown = set(aids_card) - set(aids_taken)
            for a in aids_unknown:
                print(" unknown: %s (EF.DIR)" % a)
        else:
            print("warning: EF.DIR seems to be empty!")

        # Some card applications may not be registered in EF.DIR, we will actively
        # probe for those applications
        for f in set(apps_profile) - set(apps_taken):
            try:
                data, sw = self.card.select_adf_by_aid(f.aid)
                if sw == "9000":
                    print(" %s: %s" % (f.name, f.aid))
                    apps_taken.append(f)
            except SwMatchError:
                pass
        return apps_taken

    def reset(self, cmd_app=None) -> Hexstr:
        """Perform physical card reset and obtain ATR.
        Args:
            cmd_app : Command Application State (for unregistering old file commands)
        """
        # delete all lchan != 0 (basic lchan)
        for lchan_nr in self.lchan.keys():
            if lchan_nr == 0:
                continue
            del self.lchan[lchan_nr]
        atr = i2h(self.card.reset())
        # select MF to reset internal state and to verify card really works
        self.lchan[0].select('MF', cmd_app)
        self.lchan[0].selected_adf = None
        return atr

    def add_lchan(self, lchan_nr: int) -> 'RuntimeLchan':
        """Add a logical channel to the runtime state.  You shouldn't call this
        directly but always go through RuntimeLchan.add_lchan()."""
        if lchan_nr in self.lchan.keys():
            raise ValueError('Cannot create already-existing lchan %d' % lchan_nr)
        self.lchan[lchan_nr] = RuntimeLchan(lchan_nr, self)
        return self.lchan[lchan_nr]

    def del_lchan(self, lchan_nr: int):
        if lchan_nr in self.lchan.keys():
            del self.lchan[lchan_nr]
            return True
        else:
            return False

    def get_lchan_by_cla(self, cla) -> Optional['RuntimeLchan']:
        lchan_nr = lchan_nr_from_cla(cla)
        if lchan_nr in self.lchan.keys():
            return self.lchan[lchan_nr]
        else:
            return None


class RuntimeLchan:
    """Represent the runtime state of a logical channel with a card."""

    def __init__(self, lchan_nr: int, rs: RuntimeState):
        self.lchan_nr = lchan_nr
        self.rs = rs
        self.selected_file = self.rs.mf
        self.selected_adf = None
        self.selected_file_fcp = None
        self.selected_file_fcp_hex = None

    def add_lchan(self, lchan_nr: int) -> 'RuntimeLchan':
        """Add a new logical channel from the current logical channel. Just affects
        internal state, doesn't actually open a channel with the UICC."""
        new_lchan = self.rs.add_lchan(lchan_nr)
        # See TS 102 221 Table 8.3
        if self.lchan_nr != 0:
            new_lchan.selected_file = self.get_cwd()
            new_lchan.selected_adf = self.selected_adf
        return new_lchan

    def selected_file_descriptor_byte(self) -> dict:
        return self.selected_file_fcp['file_descriptor']['file_descriptor_byte']

    def selected_file_shareable(self) -> bool:
        return self.selected_file_descriptor_byte()['shareable']

    def selected_file_structure(self) -> str:
        return self.selected_file_descriptor_byte()['structure']

    def selected_file_type(self) -> str:
        return self.selected_file_descriptor_byte()['file_type']

    def selected_file_num_of_rec(self) -> Optional[int]:
        return self.selected_file_fcp['file_descriptor'].get('num_of_rec')

    def get_cwd(self) -> CardDF:
        """Obtain the current working directory.

        Returns:
            CardDF instance
        """
        if isinstance(self.selected_file, CardDF):
            return self.selected_file
        else:
            return self.selected_file.parent

    def get_application_df(self) -> Optional[CardADF]:
        """Obtain the currently selected application DF (if any).

        Returns:
            CardADF() instance or None"""
        # iterate upwards from selected file; check if any is an ADF
        node = self.selected_file
        while node.parent != node:
            if isinstance(node, CardADF):
                return node
            node = node.parent
        return None

    def interpret_sw(self, sw: str):
        """Interpret a given status word relative to the currently selected application
        or the underlying card profile.

        Args:
            sw : Status word as string of 4 hex digits

        Returns:
            Tuple of two strings
        """
        res = None
        adf = self.get_application_df()
        if adf:
            app = adf.application
            # The application either comes with its own interpret_sw
            # method or we will use the interpret_sw method from the
            # card profile.
            if app and hasattr(app, "interpret_sw"):
                res = app.interpret_sw(sw)
        return res or self.rs.profile.interpret_sw(sw)

    def probe_file(self, fid: str, cmd_app=None):
        """Blindly try to select a file and automatically add a matching file
               object if the file actually exists."""
        if not is_hex(fid, 4, 4):
            raise ValueError(
                "Cannot select unknown file by name %s, only hexadecimal 4 digit FID is allowed" % fid)

        try:
            (data, sw) = self.rs.card._scc.select_file(fid)
        except SwMatchError as swm:
            k = self.interpret_sw(swm.sw_actual)
            if not k:
                raise(swm)
            raise RuntimeError("%s: %s - %s" % (swm.sw_actual, k[0], k[1]))

        select_resp = self.selected_file.decode_select_response(data)
        if (select_resp['file_descriptor']['file_descriptor_byte']['file_type'] == 'df'):
            f = CardDF(fid=fid, sfid=None, name="DF." + str(fid).upper(),
                       desc="dedicated file, manually added at runtime")
        else:
            if (select_resp['file_descriptor']['file_descriptor_byte']['structure'] == 'transparent'):
                f = TransparentEF(fid=fid, sfid=None, name="EF." + str(fid).upper(),
                                  desc="elementary file, manually added at runtime")
            else:
                f = LinFixedEF(fid=fid, sfid=None, name="EF." + str(fid).upper(),
                               desc="elementary file, manually added at runtime")

        self.selected_file.add_files([f])
        self.selected_file = f
        return select_resp, data

    def _select_pre(self, cmd_app):
        # unregister commands of old file
        if cmd_app and self.selected_file.shell_commands:
            for c in self.selected_file.shell_commands:
                cmd_app.unregister_command_set(c)

    def _select_post(self, cmd_app):
        # register commands of new file
        if cmd_app and self.selected_file.shell_commands:
            for c in self.selected_file.shell_commands:
                cmd_app.register_command_set(c)

    def select_file(self, file: CardFile, cmd_app=None):
        """Select a file (EF, DF, ADF, MF, ...).

        Args:
            file : CardFile [or derived class] instance
            cmd_app : Command Application State (for unregistering old file commands)
        """
        # we need to find a path from our self.selected_file to the destination
        inter_path = self.selected_file.build_select_path_to(file)
        if not inter_path:
            raise RuntimeError('Cannot determine path from %s to %s' % (self.selected_file, file))

        self._select_pre(cmd_app)

        for p in inter_path:
            try:
                if isinstance(p, CardADF):
                    (data, sw) = self.rs.card.select_adf_by_aid(p.aid)
                    self.selected_adf = p
                else:
                    (data, sw) = self.rs.card._scc.select_file(p.fid)
                self.selected_file = p
            except SwMatchError as swm:
                self._select_post(cmd_app)
                raise(swm)

        self._select_post(cmd_app)

    def select(self, name: str, cmd_app=None):
        """Select a file (EF, DF, ADF, MF, ...).

        Args:
            name : Name of file to select
            cmd_app : Command Application State (for unregistering old file commands)
        """
        # handling of entire paths with multiple directories/elements
        if '/' in name:
            prev_sel_file = self.selected_file
            pathlist = name.split('/')
            # treat /DF.GSM/foo like MF/DF.GSM/foo
            if pathlist[0] == '':
                pathlist[0] = 'MF'
            try:
                for p in pathlist:
                    self.select(p, cmd_app)
                return
            except Exception as e:
                # if any intermediate step fails, go back to where we were
                self.select_file(prev_sel_file, cmd_app)
                raise e

        sels = self.selected_file.get_selectables()
        if is_hex(name):
            name = name.lower()

        self._select_pre(cmd_app)

        if name in sels:
            f = sels[name]
            try:
                if isinstance(f, CardADF):
                    (data, sw) = self.rs.card.select_adf_by_aid(f.aid)
                else:
                    (data, sw) = self.rs.card._scc.select_file(f.fid)
                self.selected_file = f
            except SwMatchError as swm:
                k = self.interpret_sw(swm.sw_actual)
                if not k:
                    raise(swm)
                raise RuntimeError("%s: %s - %s" % (swm.sw_actual, k[0], k[1]))
            select_resp = f.decode_select_response(data)
        else:
            (select_resp, data) = self.probe_file(name, cmd_app)

        # store the raw + decoded FCP for later reference
        self.selected_file_fcp_hex = data
        self.selected_file_fcp = select_resp

        self._select_post(cmd_app)
        return select_resp

    def status(self):
        """Request STATUS (current selected file FCP) from card."""
        (data, sw) = self.rs.card._scc.status()
        return self.selected_file.decode_select_response(data)

    def get_file_for_selectable(self, name: str):
        sels = self.selected_file.get_selectables()
        return sels[name]

    def activate_file(self, name: str):
        """Request ACTIVATE FILE of specified file."""
        sels = self.selected_file.get_selectables()
        f = sels[name]
        data, sw = self.rs.card._scc.activate_file(f.fid)
        return data, sw

    def read_binary(self, length: int = None, offset: int = 0):
        """Read [part of] a transparent EF binary data.

        Args:
            length : Amount of data to read (None: as much as possible)
            offset : Offset into the file from which to read 'length' bytes
        Returns:
            binary data read from the file
        """
        if not isinstance(self.selected_file, TransparentEF):
            raise TypeError("Only works with TransparentEF")
        return self.rs.card._scc.read_binary(self.selected_file.fid, length, offset)

    def read_binary_dec(self) -> Tuple[dict, str]:
        """Read [part of] a transparent EF binary data and decode it.

        Args:
            length : Amount of data to read (None: as much as possible)
            offset : Offset into the file from which to read 'length' bytes
        Returns:
            abstract decode data read from the file
        """
        (data, sw) = self.read_binary()
        dec_data = self.selected_file.decode_hex(data)
        return (dec_data, sw)

    def update_binary(self, data_hex: str, offset: int = 0):
        """Update transparent EF binary data.

        Args:
            data_hex : hex string of data to be written
            offset : Offset into the file from which to write 'data_hex'
        """
        if not isinstance(self.selected_file, TransparentEF):
            raise TypeError("Only works with TransparentEF")
        return self.rs.card._scc.update_binary(self.selected_file.fid, data_hex, offset, conserve=self.rs.conserve_write)

    def update_binary_dec(self, data: dict):
        """Update transparent EF from abstract data. Encodes the data to binary and
        then updates the EF with it.

        Args:
            data : abstract data which is to be encoded and written
        """
        data_hex = self.selected_file.encode_hex(data)
        return self.update_binary(data_hex)

    def read_record(self, rec_nr: int = 0):
        """Read a record as binary data.

        Args:
            rec_nr : Record number to read
        Returns:
            hex string of binary data contained in record
        """
        if not isinstance(self.selected_file, LinFixedEF):
            raise TypeError("Only works with Linear Fixed EF")
        # returns a string of hex nibbles
        return self.rs.card._scc.read_record(self.selected_file.fid, rec_nr)

    def read_record_dec(self, rec_nr: int = 0) -> Tuple[dict, str]:
        """Read a record and decode it to abstract data.

        Args:
            rec_nr : Record number to read
        Returns:
            abstract data contained in record
        """
        (data, sw) = self.read_record(rec_nr)
        return (self.selected_file.decode_record_hex(data), sw)

    def update_record(self, rec_nr: int, data_hex: str):
        """Update a record with given binary data

        Args:
            rec_nr : Record number to read
            data_hex : Hex string binary data to be written
        """
        if not isinstance(self.selected_file, LinFixedEF):
            raise TypeError("Only works with Linear Fixed EF")
        return self.rs.card._scc.update_record(self.selected_file.fid, rec_nr, data_hex, conserve=self.rs.conserve_write)

    def update_record_dec(self, rec_nr: int, data: dict):
        """Update a record with given abstract data.  Will encode abstract to binary data
        and then write it to the given record on the card.

        Args:
            rec_nr : Record number to read
            data_hex : Abstract data to be written
        """
        data_hex = self.selected_file.encode_record_hex(data)
        return self.update_record(rec_nr, data_hex)

    def retrieve_data(self, tag: int = 0):
        """Read a DO/TLV as binary data.

        Args:
            tag : Tag of TLV/DO to read
        Returns:
            hex string of full BER-TLV DO including Tag and Length
        """
        if not isinstance(self.selected_file, BerTlvEF):
            raise TypeError("Only works with BER-TLV EF")
        # returns a string of hex nibbles
        return self.rs.card._scc.retrieve_data(self.selected_file.fid, tag)

    def retrieve_tags(self):
        """Retrieve tags available on BER-TLV EF.

        Returns:
            list of integer tags contained in EF
        """
        if not isinstance(self.selected_file, BerTlvEF):
            raise TypeError("Only works with BER-TLV EF")
        data, sw = self.rs.card._scc.retrieve_data(self.selected_file.fid, 0x5c)
        tag, length, value, remainder = bertlv_parse_one(h2b(data))
        return list(value)

    def set_data(self, tag: int, data_hex: str):
        """Update a TLV/DO with given binary data

        Args:
            tag : Tag of TLV/DO to be written
            data_hex : Hex string binary data to be written (value portion)
        """
        if not isinstance(self.selected_file, BerTlvEF):
            raise TypeError("Only works with BER-TLV EF")
        return self.rs.card._scc.set_data(self.selected_file.fid, tag, data_hex, conserve=self.rs.conserve_write)

    def unregister_cmds(self, cmd_app=None):
        """Unregister all file specific commands."""
        if cmd_app and self.selected_file.shell_commands:
            for c in self.selected_file.shell_commands:
                cmd_app.unregister_command_set(c)


class FileData:
    """Represent the runtime, on-card data."""

    def __init__(self, fdesc):
        self.desc = fdesc
        self.fcp = None


def interpret_sw(sw_data: dict, sw: str):
    """Interpret a given status word.

    Args:
        sw_data : Hierarchical dict of status word matches
        sw : status word to match (string of 4 hex digits)
    Returns:
        tuple of two strings (class_string, description)
    """
    for class_str, swdict in sw_data.items():
        # first try direct match
        if sw in swdict:
            return (class_str, swdict[sw])
        # next try wildcard matches
        for pattern, descr in swdict.items():
            if sw_match(sw, pattern):
                return (class_str, descr)
    return None


class CardApplication:
    """A card application is represented by an ADF (with contained hierarchy) and optionally
       some SW definitions."""

    def __init__(self, name, adf: Optional[CardADF] = None, aid: str = None, sw: dict = None):
        """
        Args:
            adf : ADF name
            sw : Dict of status word conversions
        """
        self.name = name
        self.adf = adf
        self.sw = sw or dict()
        # back-reference from ADF to Applicaiton
        if self.adf:
            self.aid = aid or self.adf.aid
            self.adf.application = self
        else:
            self.aid = aid

    def __str__(self):
        return "APP(%s)" % (self.name)

    def interpret_sw(self, sw):
        """Interpret a given status word within the application.

        Args:
            sw : Status word as string of 4 hex digits

        Returns:
            Tuple of two strings
        """
        return interpret_sw(self.sw, sw)


class CardModel(abc.ABC):
    """A specific card model, typically having some additional vendor-specific files. All
    you need to do is to define a sub-class with a list of ATRs or an overridden match
    method."""
    _atrs = []

    @classmethod
    @abc.abstractmethod
    def add_files(cls, rs: RuntimeState):
        """Add model specific files to given RuntimeState."""

    @classmethod
    def match(cls, scc: SimCardCommands) -> bool:
        """Test if given card matches this model."""
        card_atr = scc.get_atr()
        for atr in cls._atrs:
            atr_bin = toBytes(atr)
            if atr_bin == card_atr:
                print("Detected CardModel:", cls.__name__)
                return True
        return False

    @staticmethod
    def apply_matching_models(scc: SimCardCommands, rs: RuntimeState):
        """Check if any of the CardModel sub-classes 'match' the currently inserted card
        (by ATR or overriding the 'match' method). If so, call their 'add_files'
        method."""
        for m in CardModel.__subclasses__():
            if m.match(scc):
                m.add_files(rs)