import { createContext, type Context } from "react";

export type UnsavedContextValue = {
  registerWarning: (id: string, message: string | null) => void;
  requestDiscard: (action: () => void) => void;
};

/*
 * Vite Fast Refresh can re-evaluate a module while an existing route tree is
 * still mounted. Keep the context identity on the browser window so the old
 * provider and the refreshed consumers continue to refer to the same object.
 */
type ContextRegistry = Window & {
  __tallynoteUnsavedContext?: Context<UnsavedContextValue | null>;
};

const registry = typeof window === "undefined" ? null : window as ContextRegistry;
export const UnsavedContext: Context<UnsavedContextValue | null> = registry?.__tallynoteUnsavedContext ?? createContext<UnsavedContextValue | null>(null);
if (registry && !registry.__tallynoteUnsavedContext) registry.__tallynoteUnsavedContext = UnsavedContext;