from __future__ import annotations

import os
from dataclasses import dataclass


@dataclass
class Settings:
    index_dir: str
    materials_dir: str
    embedder_kind: str       # "bge-m3" | "fake"
    app_users_raw: str
    title: str
    fake_llm: bool
    rerank_kind: str       # "bge" | "fake" | "off"


def load_settings(env=None) -> Settings:
    env = os.environ if env is None else env
    return Settings(
        index_dir=env.get("STUDYHUB_INDEX_DIR", "index"),
        materials_dir=env.get("STUDYHUB_MATERIALS_DIR", "materials"),
        embedder_kind=env.get("STUDYHUB_EMBEDDER", "bge-m3"),
        app_users_raw=env.get("APP_USERS", ""),
        title=env.get("STUDYHUB_TITLE", "StudyHub"),
        fake_llm=env.get("STUDYHUB_FAKE_LLM", "0") == "1",
        rerank_kind=env.get("STUDYHUB_RERANK", "off"),
    )