Mini Shell

import os
import sys
import threading
from pathlib import Path
from typing import Any as AnyType
from typing import Iterator
from typing import Optional
from typing import Sequence
from typing import Tuple
from typing import Union

ARGUMENT = Union[str, "Any", os.PathLike]


class Thread(threading.Thread):
    """Custom thread class to capture exceptions"""

    exception: Optional[Exception] = None

    def run(self) -> None:
        try:
            super().run()
        except Exception as exc:
            self.exception = exc


class Command:
    """Command definition class."""

    __slots__ = "command"

    def __init__(
        self,
        command: Union[Sequence[ARGUMENT], str],
    ):
        if isinstance(command, str):
            command = tuple(command.split(" "))
        if not isinstance(command, (list, tuple)):
            raise TypeError("Command can be only of type string, list or tuple.")

        self.command: Tuple[ARGUMENT, ...] = tuple(
            os.fspath(c) if isinstance(c, os.PathLike) else c for c in command
        )

        for (i, command_elem) in enumerate(self.command):
            if isinstance(command_elem, Any) and isinstance(
                self._get_next_command_elem(i), Any
            ):
                raise AttributeError("Cannot use `Any()` one after another.")

    def __eq__(self, other: AnyType) -> bool:
        if isinstance(other, str):
            other = other.split(" ")

        norm_command = [
            os.fspath(c) if isinstance(c, os.PathLike) else c for c in self.command
        ]
        norm_other = [os.fspath(c) if isinstance(c, os.PathLike) else c for c in other]

        if norm_other == norm_command:
            # straightforward matching
            return True

        for (i, command_elem) in enumerate(norm_command):
            if isinstance(command_elem, Any):
                next_command_elem = self._get_next_command_elem(i)
                if next_command_elem is None:
                    if not self._are_thresholds_ok(command_elem, len(norm_other)):
                        return False
                    return True
                else:
                    next_matching_elem = self._get_next_matching_elem_index(
                        norm_other, next_command_elem
                    )
                    if next_matching_elem is None:
                        return False
                    else:
                        if not self._are_thresholds_ok(
                            command_elem, next_matching_elem
                        ):
                            return False

                        norm_other = norm_other[next_matching_elem:]
            else:
                if len(norm_other) == 0 or norm_other.pop(0) != command_elem:
                    return False

        return len(norm_other) == 0

    def __iter__(self) -> Iterator:
        return iter(self.command)

    @staticmethod
    def _are_thresholds_ok(command_elem: "Any", value: int) -> bool:
        if command_elem.max is not None and value > command_elem.max:
            return False
        if command_elem.min is not None and value < command_elem.min:
            return False
        return True

    def _get_next_command_elem(self, index: int) -> Optional[ARGUMENT]:
        try:
            return self.command[index + 1]
        except IndexError:
            return None

    @staticmethod
    def _get_next_matching_elem_index(
        other: Sequence[ARGUMENT], elem: ARGUMENT
    ) -> Optional[int]:
        return next(
            (i for i, other_elem in enumerate(other) if elem == other_elem), None
        )

    def __hash__(self) -> int:
        return hash(self.command)

    def __repr__(self) -> str:
        return str(self.command)

    def __str__(self) -> str:
        return str(self.command)


class Any:
    """Wildcard definition class."""

    def __init__(self, *, min: Optional[int] = None, max: Optional[int] = None) -> None:
        if min is not None and max is not None and min > max:
            raise AttributeError("min cannot be greater than max")
        self.min: Optional[int] = min
        self.max: Optional[int] = max

    def __str__(self) -> str:
        return f"{self.__class__.__name__} (min={self.min}, max={self.max})"

    def __repr__(self) -> str:
        return str(self)


class Program:
    """Specifies the name of the final program to be executed."""

    def __init__(self, program: str) -> None:
        self.program: str = program

    def __repr__(self) -> str:
        return f"{self.__class__.__name__}({self.program!r})"

    def __eq__(self, other: AnyType) -> bool:
        if isinstance(other, str):
            if Path(other).name == self.program:
                return True

            if sys.platform.startswith("win"):
                for ext in os.environ.get("PATHEXT", "").split(os.pathsep):
                    if (
                        Path(other).name.lower()
                        == Path(self.program).with_suffix(ext).name.lower()
                    ):
                        return True
        return False

    def __hash__(self) -> int:
        return hash(self.program)