from __future__ import annotations

import os
from pathlib import Path


APP_DIR_NAME = "BakRest"
CONFIG_ENV_VAR = "BAKREST_CONFIG"


def program_data_dir() -> Path:
    base = os.environ.get("PROGRAMDATA")
    if base:
        return Path(base) / APP_DIR_NAME
    return Path.home() / f".{APP_DIR_NAME.lower()}"


def default_config_path() -> Path:
    configured = os.environ.get(CONFIG_ENV_VAR)
    if configured:
        return Path(configured).expanduser()
    return program_data_dir() / "config.toml"


def expand_path(value: str) -> Path:
    return Path(os.path.expandvars(value)).expanduser()