import os
from typing import List


def _get_env(name: str, default: str = "") -> str:
    return os.getenv(name, default).strip()


def get_gradient_endpoint_url() -> str:
    return _get_env("GRADIENT_ENDPOINT_URL")


def get_gradient_api_key() -> str:
    return _get_env("GRADIENT_API_KEY")


def get_gradient_auth_scheme() -> str:
    # 'authorization_bearer' or 'x_api_key'
    return _get_env("GRADIENT_AUTH_SCHEME", "authorization_bearer").lower()


def get_route_keywords() -> List[str]:
    raw = _get_env("ROUTE_KEYWORDS", "ai,model,ml,gpt,router,gradient")
    return [kw.strip().lower() for kw in raw.split(",") if kw.strip()]