"use client";

import {
  createContext,
  useContext,
  useEffect,
  useRef,
  useState,
  type ReactNode,
} from "react";
import { useRouter } from "next/navigation";
import { realtime, RT_SETTINGS_CHANGED, type RtSettingsData } from "@/lib/realtime";

const AllowCommentsContext = createContext(true);

/** 前台是否开放评论（SSR 初值 + 后台开关热更新） */
export function useAllowComments(): boolean {
  return useContext(AllowCommentsContext);
}

/**
 * 根布局注入：关闭评论后前台立即隐藏评论区/数量；开启则刷新以拉回评论。
 */
export default function CommentsPolicyProvider({
  allowComments,
  children,
}: {
  allowComments: boolean;
  children: ReactNode;
}) {
  const router = useRouter();
  const [open, setOpen] = useState(allowComments);
  const openRef = useRef(open);
  openRef.current = open;

  useEffect(() => {
    setOpen(allowComments);
  }, [allowComments]);

  useEffect(() => {
    return realtime.on<RtSettingsData>(RT_SETTINGS_CHANGED, (data) => {
      if (typeof data?.allow_comments !== "boolean") return;
      if (openRef.current === data.allow_comments) return;
      setOpen(data.allow_comments);
      router.refresh();
    });
  }, [router]);

  return (
    <AllowCommentsContext.Provider value={open}>{children}</AllowCommentsContext.Provider>
  );
}