"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 AllowMessagesContext = createContext(true);

/** 前台是否开放私聊/群聊（SSR 初值 + 后台开关热更新） */
export function useAllowMessages(): boolean {
  return useContext(AllowMessagesContext);
}

/**
 * 根布局注入：关闭消息后前台立即隐藏入口；开启则刷新以拉回会话。
 */
export default function MessagesPolicyProvider({
  allowMessages,
  children,
}: {
  allowMessages: boolean;
  children: ReactNode;
}) {
  const router = useRouter();
  const [open, setOpen] = useState(allowMessages);
  const openRef = useRef(open);
  openRef.current = open;

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

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

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