"""Account path helpers for Chrome user-data directories."""

from __future__ import annotations

import hashlib
import os
import re

from . import appconfig


SLUG_PATTERN = re.compile(r"^[a-z0-9_]+$")


class ConfigPathError(RuntimeError):
    """Raised when account path configuration is invalid."""


def make_slug(alias) -> str:
    """Return a stable unique slug for an account alias."""

    text = str(alias or "").strip()
    if not text:
        raise ConfigPathError("别名不能为空")
    base = re.sub(r"[^a-z0-9_]+", "_", text.lower()).strip("_")
    suffix = hashlib.sha1(text.encode("utf-8")).hexdigest()[:8]
    return f"{base}_{suffix}" if base else f"account_{suffix}"


def _validate_slug(slug) -> str:
    text = str(slug or "").strip()
    if not text:
        raise ConfigPathError("slug 不能为空")
    if not SLUG_PATTERN.fullmatch(text):
        raise ConfigPathError("slug 只能包含小写字母、数字和下划线")
    return text


def ensure_user_data_dir(slug, root=None, config=None) -> str:
    """Create and return the absolute user-data-dir path for a slug."""

    safe_slug = _validate_slug(slug)
    user_data_root = root if root is not None else appconfig.user_data_root(config)
    if not str(user_data_root).strip():
        raise ConfigPathError("user_data_root 不能为空")
    path = os.path.abspath(os.path.join(str(user_data_root), safe_slug))
    os.makedirs(path, exist_ok=True)
    return path