"""Canonical Blueforce device identity."""

from __future__ import annotations

import os
import re
from pathlib import Path

DEALER_ID_PATTERN = re.compile(r"^[0-9]{8}$")
DEALER_ID_FILE = Path("/etc/blueforce/dealer-id")


def validate_dealer_id(value: str) -> bool:
    return bool(DEALER_ID_PATTERN.fullmatch(str(value).strip()))


def dealer_id_file(path: str | os.PathLike[str] | None = None) -> Path:
    return Path(path) if path is not None else Path(
        os.environ.get("BF_DEALER_ID_FILE", str(DEALER_ID_FILE))
    )


def read_dealer_id(path: str | os.PathLike[str] | None = None) -> str:
    value = dealer_id_file(path).read_text(encoding="utf-8").strip()
    if not validate_dealer_id(value):
        raise ValueError("dealer-id must contain exactly 8 digits")
    return value


def identity_for(dealer_id: str) -> dict[str, str]:
    dealer_id = str(dealer_id).strip()
    if not validate_dealer_id(dealer_id):
        raise ValueError("dealer-id must contain exactly 8 digits")
    return {
        "dealer_id": dealer_id,
        "username": f"bf-{dealer_id}",
        "hostname": f"bf-{dealer_id}",
        "device_id": f"BF-{dealer_id}",
        "active_user": f"bf-{dealer_id}",
    }


def current_identity(path: str | os.PathLike[str] | None = None) -> dict[str, str]:
    return identity_for(read_dealer_id(path))