core/config.py

import os
from pathlib import Path
from dotenv import load_dotenv

ENV_PATH = Path(".env")
ENV_VAR_NAME = "GOOGLE_API_KEY"  # Keep Google-style key name for Gemini

# Load .env once on import (local runs)
load_dotenv(dotenv_path=ENV_PATH, override=False)

def in_hf_spaces() -> bool:
    """Detect if running inside Hugging Face Spaces."""
    return bool(os.getenv("SPACE_ID"))

def get_api_key() -> str | None:
    """Read the API key (from env or Space Secret)."""
    return os.getenv(ENV_VAR_NAME)

def ensure_env_file() -> None:
    if not ENV_PATH.exists():
        ENV_PATH.write_text("")

def set_api_key(value: str, var_name: str = ENV_VAR_NAME) -> None:
    """
    Persist the key to .env for local runs.
    On Spaces, DO NOT write to disk (no-op) — use session key instead.
    """
    if in_hf_spaces():
        return  # no-op on Spaces

    value = (value or "").strip()
    ensure_env_file()

    lines = ENV_PATH.read_text().splitlines()
    out, found = [], False
    for line in lines:
        if line.strip().startswith(f"{var_name}="):
            out.append(f"{var_name}={value}")
            found = True
        else:
            out.append(line)
    if not found:
        out.append(f"{var_name}={value}")

    ENV_PATH.write_text("\n".join(out) + "\n")
    os.environ[var_name] = value  # also set for this process