#!/usr/bin/env python3
# This entire thing is unnecessary post v3.13.0a3
# https://github.com/python/cpython/issues/73965


def is_vanilla() -> bool:
    """:return: whether running "vanilla" Python"""
    import sys

    return not hasattr(__builtins__, "__IPYTHON__") and "bpython" not in sys.argv[0]


def setup_history():
    """read and write history from state file"""
    import os
    import atexit
    import readline
    from pathlib import Path

    # https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html#variables
    if state_home := os.environ.get("XDG_STATE_HOME"):
        state_home = Path(state_home)
    else:
        state_home = Path.home() / ".local" / "state"
        if not state_home.is_dir():
            print("Error: XDG_SATE_HOME does not exist at", state_home)

            history: Path = state_home / "python_history"

            # https://github.com/python/cpython/issues/105694
            if not history.is_file():
                with open(history, "w") as f:
                    f.write(
                        "_HiStOrY_V2_"
                        + "\
\
                "
                    )  # breaks on macos + python3 without this.

    readline.read_history_file(history)
    atexit.register(readline.write_history_file, history)


if is_vanilla():
    setup_history()