from datetime import datetime
from persona import persona_path, get_user, get_persona


def log_turn(
    session_id: str,
    user_msg: str,
    assistant_msg: str,
    backend_label: str = "",
    host: str = "",
) -> None:
    today = datetime.now().strftime("%Y-%m-%d")
    sessions_dir = persona_path() / "sessions"
    sessions_dir.mkdir(exist_ok=True)

    log_file = sessions_dir / f"{today}.md"
    timestamp = datetime.now().strftime("%H:%M")
    is_new = not log_file.exists()

    meta_parts = [p for p in [backend_label, host] if p]
    meta = f" · {' / '.join(meta_parts)}" if meta_parts else ""

    # Use the actual user/persona names from the current request context
    user_label = get_user().title()
    persona_label = get_persona().title()

    with open(log_file, "a") as f:
        if is_new:
            f.write(f"# Session Log — {today}\n")
        f.write(
            f"\n### [{timestamp}] `{session_id}`{meta}\n"
            f"**{user_label}:** {user_msg}\n\n"
            f"**{persona_label}:** {assistant_msg}\n"
        )