/**
 * Session token holder: memory first, mirrored to localStorage so a reload
 * keeps the session. Listeners let the auth store react when the API client
 * clears a token (401) or a mutation hands back a re-issued one.
 */

const STORAGE_KEY = "tmbh.session";

let memory: string | null | undefined;
const listeners = new Set<(token: string | null) => void>();

export function getSessionToken(): string | null {
  if (memory !== undefined) return memory;
  if (typeof window === "undefined") return null;
  memory = window.localStorage.getItem(STORAGE_KEY);
  return memory;
}

export function setSessionToken(token: string | null): void {
  memory = token;
  if (typeof window !== "undefined") {
    if (token === null) window.localStorage.removeItem(STORAGE_KEY);
    else window.localStorage.setItem(STORAGE_KEY, token);
  }
  for (const listener of listeners) listener(token);
}

export function onSessionTokenChange(listener: (token: string | null) => void): () => void {
  listeners.add(listener);
  return () => listeners.delete(listener);
}