"""
In-process opaque session IDs (browser cookie / Bearer token value).

Single-process only; restarting the server clears every session (empty dict).
"""

from __future__ import annotations

import secrets
import threading
import time
from dataclasses import dataclass

_lock = threading.Lock()


@dataclass(frozen=True)
class Session:
	username: str
	created_at: float


_sessions: dict[str, Session] = {}


def create_session(username: str) -> str:
	sid = secrets.token_urlsafe(32)
	with _lock:
		_sessions[sid] = Session(username=username, created_at=time.time())
	return sid


def get_session(session_id: str | None) -> Session | None:
	if not session_id:
		return None
	raw = session_id.strip()
	if not raw:
		return None
	with _lock:
		return _sessions.get(raw)


def revoke_session(session_id: str | None) -> None:
	if not session_id:
		return
	raw = session_id.strip()
	if not raw:
		return
	with _lock:
		_sessions.pop(raw, None)


def clear_all_sessions() -> None:
	with _lock:
		_sessions.clear()