import { type Dispatch, type SetStateAction, useEffect, useState } from "react";

export function usePersistentState<T>(key: string, initialValue: T | (() => T)): [T, Dispatch<SetStateAction<T>>] {
  const [value, setValue] = useState<T>(() => {
    const fallback = typeof initialValue === "function" ? (initialValue as () => T)() : initialValue;
    if (typeof window === "undefined") return fallback;
    try {
      const stored = window.localStorage.getItem(key);
      return stored ? JSON.parse(stored) as T : fallback;
    } catch {
      return fallback;
    }
  });

  useEffect(() => {
    try {
      window.localStorage.setItem(key, JSON.stringify(value));
    } catch {
      // Storage can be unavailable in private mode; in-memory state still works.
    }
  }, [key, value]);

  return [value, setValue];
}