type FloatingToastListener = (message: string) => void;

const listeners = new Set<FloatingToastListener>();

export function registerFloatingToastListener(fn: FloatingToastListener) {
  listeners.add(fn);
  return () => {
    listeners.delete(fn);
  };
}

/** 已有页面宿主时返回 true，否则调用方应回退到原生 toast */
export function showFloatingToast(message: string): boolean {
  const text = message.trim();
  if (!text || listeners.size === 0) return false;
  listeners.forEach((fn) => fn(text));
  return true;
}