from __future__ import annotations

import os
from pathlib import Path


REPO_ROOT = Path(__file__).resolve().parents[1]
MISSING_ROOT = REPO_ROOT / "tests" / ".external-data-not-configured"


def external_dir(env_name: str, fallback_name: str) -> Path:
    configured = (os.environ.get(env_name) or "").strip()
    if configured:
        return Path(configured).expanduser()
    return MISSING_ROOT / fallback_name