"use client";

import {
  CheckCircle2,
  ExternalLink,
  GitBranch,
  Globe,
  Image as ImageIcon,
  Loader2,
  MessageSquare,
  MessagesSquare,
  Paperclip,
  RotateCcw,
  UserPlus,
} from "lucide-react";
import { useCallback, useEffect, useMemo, useRef, useState, type KeyboardEvent } from "react";
import {
  AdminExtChipEditor,
  AdminPageHeader,
  AdminSettingsActions,
  AdminSettingsGroup,
  AdminSettingsPage,
  AdminSettingsRow,
  AdminSettingsWork,
  AdminStepper,
  AdminSwitch,
} from "@/components/admin";
import { apiGetAdminSettings, apiUpdateSiteSettings, type PublicSettings } from "@/lib/api";
import { toast } from "@/lib/toast";
import useUnsavedGuard from "@/hooks/useUnsavedGuard";
import BasicIdentityPanel from "./BasicIdentityPanel";
import BrandSeoPanel from "./BrandSeoPanel";
import FooterLinksPanel from "./FooterLinksPanel";
import ConfirmDialog from "@/components/ConfirmDialog";

function extsEqual(a: string[], b: string[]) {
  if (a.length !== b.length) return false;
  return a.every((v, i) => v === b[i]);
}

/** 与后端 DefaultTimelineGitAdapterJSON 对齐的内置默认适配器 */
const DEFAULT_TIMELINE_GIT_IMPORT = `{
  "max_pages": 10,
  "max_commits": 100,
  "sources": [
    {
      "id": "github",
      "host": "github.com",
      "list_path": "^/(?P<owner>[^/]+)/(?P<repo>[^/]+)/commits/(?P<ref>[^/]+)/?$",
      "commit_path": "^/(?P<owner>[^/]+)/(?P<repo>[^/]+)/commit/(?P<sha>[0-9a-fA-F]{7,64})/?$",
      "api_url": "https://api.github.com/repos/{owner}/{repo}/commits",
      "commit_api": "https://api.github.com/repos/{owner}/{repo}/commits/{sha}",
      "query": { "sha": "{ref}", "per_page": "100", "page": "{page}" },
      "headers": { "User-Agent": "jiang13-bbs", "Accept": "application/vnd.github+json" },
      "pagination": "link_header",
      "item": {
        "sha": "sha",
        "date": "commit.committer.date",
        "message": "commit.message",
        "source_url": "html_url"
      }
    },
    {
      "id": "gitea",
      "host": "*",
      "list_path": "^/(?P<owner>[^/]+)/(?P<repo>[^/]+)/commits/branch/(?P<ref>.+)/?$",
      "commit_path": "^/(?P<owner>[^/]+)/(?P<repo>[^/]+)/commit/(?P<sha>[0-9a-fA-F]{7,64})/?$",
      "api_url": "https://{host}/api/v1/repos/{owner}/{repo}/commits",
      "commit_api": "https://{host}/api/v1/repos/{owner}/{repo}/git/commits/{sha}",
      "query": { "sha": "{ref}", "limit": "50", "page": "{page}" },
      "headers": { "User-Agent": "jiang13-bbs", "Accept": "application/json" },
      "pagination": "query_page",
      "item": {
        "sha": "sha",
        "date": "created",
        "message": "commit.message",
        "source_url": "html_url"
      }
    }
  ]
}`;

type SectionId = "basic" | "content" | "gitimport";

const NAV: { id: SectionId; label: string }[] = [
  { id: "basic", label: "基本信息" },
  { id: "content", label: "内容与互动" },
  { id: "gitimport", label: "提交导入" },
];

const COMING_SOON = ["安全与限流", "邮件", "对象存储", "敏感词", "系统维护"];

function parseSection(hash: string): SectionId {
  const id = hash.replace(/^#/, "");
  if (id === "content" || id === "gitimport" || id === "basic") return id;
  return "basic";
}

function InstantNote({ saving }: { saving?: boolean }) {
  return <span className="admin-settings-instant">{saving ? "正在保存…" : "修改后立即生效"}</span>;
}

export default function SettingsAdmin({ initial }: { initial: PublicSettings }) {
  const [live, setLive] = useState(initial);
  const [allowRegister, setAllowRegister] = useState(initial.allow_register);
  const [allowComments, setAllowComments] = useState(initial.allow_comments !== false);
  const [allowMessages, setAllowMessages] = useState(initial.allow_messages !== false);
  const [postLinkNewTab, setPostLinkNewTab] = useState(initial.post_link_new_tab !== false);
  const [togglingReg, setTogglingReg] = useState(false);
  const [togglingComments, setTogglingComments] = useState(false);
  const [togglingMessages, setTogglingMessages] = useState(false);
  const [togglingLink, setTogglingLink] = useState(false);
  const [active, setActive] = useState<SectionId>("basic");
  const navRefs = useRef<(HTMLAnchorElement | null)[]>([]);

  const [extLimit, setExtLimit] = useState(initial.attachment_ext_limit !== false);
  const [exts, setExts] = useState<string[]>(() => [...(initial.attachment_exts || [])]);
  const [savedExts, setSavedExts] = useState<string[]>(() => [...(initial.attachment_exts || [])]);
  const [attMaxMB, setAttMaxMB] = useState(initial.attachment_max_mb || 20);
  const [attMaxCount, setAttMaxCount] = useState(initial.attachment_max_count || 10);
  const [imageMaxMB, setImageMaxMB] = useState(initial.image_max_mb || 5);
  const [togglingExtLimit, setTogglingExtLimit] = useState(false);
  const [savingLimits, setSavingLimits] = useState(false);
  const [savingExts, setSavingExts] = useState(false);
  const confirmedLimits = useRef({
    attachment_max_mb: initial.attachment_max_mb || 20,
    attachment_max_count: initial.attachment_max_count || 10,
    image_max_mb: initial.image_max_mb || 5,
  });
  const limitsReq = useRef(0);

  const [gitImportJSON, setGitImportJSON] = useState("");
  const [savedGitImport, setSavedGitImport] = useState("");
  const [gitImportLoading, setGitImportLoading] = useState(false);
  const [gitImportLoaded, setGitImportLoaded] = useState(false);
  const [savingGitImport, setSavingGitImport] = useState(false);
  const [restoreGitOpen, setRestoreGitOpen] = useState(false);
  const [gitValidateMsg, setGitValidateMsg] = useState<{ ok: boolean; text: string } | null>(null);

  const [basicDirty, setBasicDirty] = useState(false);
  const [brandDirty, setBrandDirty] = useState(false);
  const [seoDirty, setSeoDirty] = useState(false);
  const [pendingSection, setPendingSection] = useState<SectionId | null>(null);

  const extsDirty = useMemo(() => !extsEqual(exts, savedExts), [exts, savedExts]);
  const gitImportDirty = gitImportJSON !== savedGitImport;
  const gitPreview = useMemo(() => {
    try {
      const parsed = JSON.parse(gitImportJSON) as {
        max_pages?: unknown;
        max_commits?: unknown;
        sources?: unknown;
      };
      if (!Array.isArray(parsed.sources)) return null;
      const sources = parsed.sources
        .filter((s): s is Record<string, unknown> => !!s && typeof s === "object")
        .map((s) => ({
          id: typeof s.id === "string" ? s.id : "—",
          host: typeof s.host === "string" ? s.host : "*",
        }));
      return {
        maxPages: typeof parsed.max_pages === "number" ? parsed.max_pages : null,
        maxCommits: typeof parsed.max_commits === "number" ? parsed.max_commits : null,
        sources,
      };
    } catch {
      return null;
    }
  }, [gitImportJSON]);

  const tabDirty =
    active === "basic" ? basicDirty || brandDirty || seoDirty : active === "content" ? extsDirty : gitImportDirty;

  const leave = useUnsavedGuard(tabDirty);

  const onBasicDirty = useCallback((d: boolean) => setBasicDirty(d), []);
  const onBrandDirty = useCallback((d: boolean) => setBrandDirty(d), []);
  const onSeoDirty = useCallback((d: boolean) => setSeoDirty(d), []);

  const loadGitImport = async () => {
    if (gitImportLoading) return;
    setGitImportLoading(true);
    try {
      const res = await apiGetAdminSettings();
      const raw = res.timeline_git_import?.trim() || DEFAULT_TIMELINE_GIT_IMPORT;
      let pretty = raw;
      try {
        pretty = JSON.stringify(JSON.parse(raw), null, 2);
      } catch {
        /* 保持原文 */
      }
      setGitImportJSON(pretty);
      setSavedGitImport(pretty);
      setGitImportLoaded(true);
      setGitValidateMsg(null);
    } catch (e) {
      toast(e instanceof Error ? e.message : "加载适配器失败");
    } finally {
      setGitImportLoading(false);
    }
  };

  useEffect(() => {
    void loadGitImport();
    // 仅挂载时拉取一次
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, []);

  useEffect(() => {
    const apply = () => setActive(parseSection(window.location.hash));
    apply();
    if (!window.location.hash) {
      history.replaceState(null, "", `${window.location.pathname}${window.location.search}#basic`);
    }
    window.addEventListener("hashchange", apply);
    return () => window.removeEventListener("hashchange", apply);
  }, []);

  const goSection = (id: SectionId) => {
    if (id === active) return;
    setActive(id);
    const next = `${window.location.pathname}${window.location.search}#${id}`;
    history.replaceState(null, "", next);
    document.getElementById("main")?.scrollTo({ top: 0 });
    if (id === "gitimport" && !gitImportLoaded && !gitImportLoading) {
      void loadGitImport();
    }
  };

  const selectTab = (id: SectionId) => {
    if (id === active) return;
    if (tabDirty) {
      setPendingSection(id);
      return;
    }
    goSection(id);
  };

  const onNavKeyDown = (e: KeyboardEvent<HTMLAnchorElement>, i: number) => {
    if (e.key !== "ArrowDown" && e.key !== "ArrowUp" && e.key !== "Home" && e.key !== "End" && e.key !== "ArrowRight" && e.key !== "ArrowLeft") {
      return;
    }
    e.preventDefault();
    let next = i;
    if (e.key === "ArrowDown" || e.key === "ArrowRight") next = (i + 1) % NAV.length;
    else if (e.key === "ArrowUp" || e.key === "ArrowLeft") next = (i + NAV.length - 1) % NAV.length;
    else if (e.key === "Home") next = 0;
    else next = NAV.length - 1;
    selectTab(NAV[next].id);
    navRefs.current[next]?.focus();
  };

  const validateGitImportClient = (): boolean => {
    try {
      JSON.parse(gitImportJSON);
      setGitValidateMsg({ ok: true, text: "JSON 语法有效（服务端保存时还会做结构校验）" });
      return true;
    } catch (e) {
      setGitValidateMsg({
        ok: false,
        text: e instanceof Error ? `JSON 无效：${e.message}` : "JSON 无效",
      });
      return false;
    }
  };

  const saveGitImport = async () => {
    if (savingGitImport) return;
    if (!validateGitImportClient()) {
      toast("请先修正 JSON 语法");
      return;
    }
    const snap = gitImportJSON;
    setSavingGitImport(true);
    try {
      await apiUpdateSiteSettings({ timeline_git_import: snap });
      const res = await apiGetAdminSettings();
      const raw = res.timeline_git_import?.trim() || snap;
      let pretty = raw;
      try {
        pretty = JSON.stringify(JSON.parse(raw), null, 2);
      } catch {
        /* 保持 */
      }
      setSavedGitImport(pretty);
      setGitImportJSON((cur) => (cur === snap ? pretty : cur));
      toast("提交导入适配器已保存", "ok");
    } catch (e) {
      toast(e instanceof Error ? e.message : "保存失败");
    } finally {
      setSavingGitImport(false);
    }
  };

  const restoreGitDefault = async () => {
    setSavingGitImport(true);
    try {
      let pretty = DEFAULT_TIMELINE_GIT_IMPORT;
      try {
        pretty = JSON.stringify(JSON.parse(DEFAULT_TIMELINE_GIT_IMPORT), null, 2);
      } catch {
        /* 保持 */
      }
      await apiUpdateSiteSettings({ timeline_git_import: pretty });
      setGitImportJSON(pretty);
      setSavedGitImport(pretty);
      setGitValidateMsg(null);
      setRestoreGitOpen(false);
      toast("已恢复默认适配器", "ok");
    } catch (e) {
      toast(e instanceof Error ? e.message : "恢复失败");
    } finally {
      setSavingGitImport(false);
    }
  };

  const toggleRegister = async () => {
    if (togglingReg) return;
    const next = !allowRegister;
    setTogglingReg(true);
    try {
      const res = await apiUpdateSiteSettings({ allow_register: next });
      setAllowRegister(res.allow_register);
      toast(res.allow_register ? "已开放注册" : "已关闭注册", "ok");
    } catch (e) {
      toast(e instanceof Error ? e.message : "保存失败");
    } finally {
      setTogglingReg(false);
    }
  };

  const toggleComments = async () => {
    if (togglingComments) return;
    const next = !allowComments;
    setTogglingComments(true);
    try {
      const res = await apiUpdateSiteSettings({ allow_comments: next });
      setAllowComments(res.allow_comments);
      toast(res.allow_comments ? "已开放评论" : "已关闭评论", "ok");
    } catch (e) {
      toast(e instanceof Error ? e.message : "保存失败");
    } finally {
      setTogglingComments(false);
    }
  };

  const toggleMessages = async () => {
    if (togglingMessages) return;
    const next = !allowMessages;
    setTogglingMessages(true);
    try {
      const res = await apiUpdateSiteSettings({ allow_messages: next });
      setAllowMessages(res.allow_messages);
      toast(res.allow_messages ? "已开放消息" : "已关闭消息", "ok");
    } catch (e) {
      toast(e instanceof Error ? e.message : "保存失败");
    } finally {
      setTogglingMessages(false);
    }
  };

  const togglePostLinkNewTab = async () => {
    if (togglingLink) return;
    const next = !postLinkNewTab;
    setTogglingLink(true);
    try {
      const res = await apiUpdateSiteSettings({ post_link_new_tab: next });
      setPostLinkNewTab(res.post_link_new_tab !== false);
      toast(res.post_link_new_tab !== false ? "帖子与评论外链将在新标签打开" : "帖子与评论外链将在当前页打开", "ok");
    } catch (e) {
      toast(e instanceof Error ? e.message : "保存失败");
    } finally {
      setTogglingLink(false);
    }
  };

  const toggleExtLimit = async () => {
    if (togglingExtLimit) return;
    const next = !extLimit;
    setTogglingExtLimit(true);
    try {
      const res = await apiUpdateSiteSettings({ attachment_ext_limit: next });
      setExtLimit(res.attachment_ext_limit !== false);
      toast(res.attachment_ext_limit !== false ? "已开启附件类型限制" : "已关闭附件类型限制", "ok");
    } catch (e) {
      toast(e instanceof Error ? e.message : "保存失败");
    } finally {
      setTogglingExtLimit(false);
    }
  };

  const saveUploadLimits = async (patch: {
    attachment_max_mb?: number;
    attachment_max_count?: number;
    image_max_mb?: number;
  }) => {
    const ticket = ++limitsReq.current;
    setSavingLimits(true);
    try {
      const res = await apiUpdateSiteSettings(patch);
      if (ticket !== limitsReq.current) return;
      confirmedLimits.current = {
        attachment_max_mb: res.attachment_max_mb,
        attachment_max_count: res.attachment_max_count,
        image_max_mb: res.image_max_mb,
      };
      setAttMaxMB(res.attachment_max_mb);
      setAttMaxCount(res.attachment_max_count);
      setImageMaxMB(res.image_max_mb);
      toast("上传限额已保存", "ok");
    } catch (e) {
      if (ticket !== limitsReq.current) return;
      setAttMaxMB(confirmedLimits.current.attachment_max_mb);
      setAttMaxCount(confirmedLimits.current.attachment_max_count);
      setImageMaxMB(confirmedLimits.current.image_max_mb);
      toast(e instanceof Error ? e.message : "保存失败");
    } finally {
      if (ticket === limitsReq.current) setSavingLimits(false);
    }
  };

  const limitsTimer = useRef<ReturnType<typeof setTimeout> | null>(null);
  const pendingLimits = useRef<typeof confirmedLimits.current>({ ...confirmedLimits.current });
  const scheduleLimitSave = (patch: {
    attachment_max_mb?: number;
    attachment_max_count?: number;
    image_max_mb?: number;
  }) => {
    pendingLimits.current = { ...pendingLimits.current, ...patch };
    if (limitsTimer.current) clearTimeout(limitsTimer.current);
    limitsTimer.current = setTimeout(() => {
      const next = pendingLimits.current;
      void saveUploadLimits({
        attachment_max_mb: next.attachment_max_mb,
        attachment_max_count: next.attachment_max_count,
        image_max_mb: next.image_max_mb,
      });
    }, 450);
  };

  useEffect(() => {
    return () => {
      if (limitsTimer.current) clearTimeout(limitsTimer.current);
    };
  }, []);

  const saveExts = async () => {
    if (savingExts || !extsDirty) return;
    const snap = [...exts];
    setSavingExts(true);
    try {
      const res = await apiUpdateSiteSettings({ attachment_exts: snap });
      setSavedExts([...res.attachment_exts]);
      setExts((cur) => (extsEqual(cur, snap) ? [...res.attachment_exts] : cur));
      toast("附件扩展名已保存", "ok");
    } catch (e) {
      toast(e instanceof Error ? e.message : "保存失败");
    } finally {
      setSavingExts(false);
    }
  };

  const leaveOpen = leave.leaveOpen || pendingSection != null;
  const confirmLeave = () => {
    if (pendingSection) {
      const next = pendingSection;
      setPendingSection(null);
      goSection(next);
      return;
    }
    leave.confirmLeave();
  };
  const cancelLeave = () => {
    setPendingSection(null);
    leave.cancelLeave();
  };

  const nav = (
    <nav className="admin-settings-nav" aria-label="设置分类">
      {NAV.map((item, i) => {
        const isActive = active === item.id;
        return (
          <a
            key={item.id}
            ref={(el) => {
              navRefs.current[i] = el;
            }}
            href={`#${item.id}`}
            className="admin-settings-nav-link"
            aria-current={isActive ? "page" : undefined}
            onClick={(e) => {
              e.preventDefault();
              selectTab(item.id);
            }}
            onKeyDown={(e) => onNavKeyDown(e, i)}
          >
            {item.label}
          </a>
        );
      })}
      <details className="admin-settings-nav-soon">
        <summary className="admin-settings-nav-soon-summary">未开放模块</summary>
        <ul className="admin-settings-nav-soon-list">
          {COMING_SOON.map((name) => (
            <li key={name}>{name}</li>
          ))}
        </ul>
      </details>
    </nav>
  );

  return (
    <AdminSettingsPage className={active === "gitimport" ? "is-fill" : undefined}>
      <AdminPageHeader
        icon={Globe}
        title="站点设置"
        description="名称、关键词、Logo 与页脚在「基本信息」；主题色请到「外观」调整"
      />

      <AdminSettingsWork nav={nav}>
        <div id={`settings-panel-${active}`} className="admin-settings-stack">
          {active === "basic" && (
            <>
              <BasicIdentityPanel initial={live} onSaved={setLive} onDirtyChange={onBasicDirty} />
              <BrandSeoPanel initial={live} onSaved={setLive} onDirtyChange={onBrandDirty} />
              <FooterLinksPanel initial={live} onSaved={setLive} onDirtyChange={onSeoDirty} />
            </>
          )}

          {active === "content" && (
            <>
              <AdminSettingsGroup
                title="内容与互动"
                description="开关改完立即写入，无需再点保存。"
              >
                <AdminSettingsRow
                  label={
                    <span className="inline-flex items-center gap-1.5">
                      <UserPlus size={15} /> 开放注册
                    </span>
                  }
                  hintBelow="关闭后游客无法提交注册，已有账号仍可登录。"
                >
                  <div className="flex items-center gap-2">
                    <AdminSwitch
                      checked={allowRegister}
                      disabled={togglingReg}
                      onChange={() => void toggleRegister()}
                      label="开放注册"
                    />
                    <InstantNote saving={togglingReg} />
                  </div>
                </AdminSettingsRow>
                <AdminSettingsRow
                  label={
                    <span className="inline-flex items-center gap-1.5">
                      <MessageSquare size={15} /> 开放评论
                    </span>
                  }
                  hintBelow="关闭后前台不展示评论入口、评论数量与已有评论。"
                >
                  <div className="flex items-center gap-2">
                    <AdminSwitch
                      checked={allowComments}
                      disabled={togglingComments}
                      onChange={() => void toggleComments()}
                      label="开放评论"
                    />
                    <InstantNote saving={togglingComments} />
                  </div>
                </AdminSettingsRow>
                <AdminSettingsRow
                  label={
                    <span className="inline-flex items-center gap-1.5">
                      <MessagesSquare size={15} /> 开放消息
                    </span>
                  }
                  hintBelow="关闭后前台不展示私聊与群聊入口；已有会话仍可由后台监管。"
                >
                  <div className="flex items-center gap-2">
                    <AdminSwitch
                      checked={allowMessages}
                      disabled={togglingMessages}
                      onChange={() => void toggleMessages()}
                      label="开放消息"
                    />
                    <InstantNote saving={togglingMessages} />
                  </div>
                </AdminSettingsRow>
                <AdminSettingsRow
                  label={
                    <span className="inline-flex items-center gap-1.5">
                      <ExternalLink size={15} /> 外链新标签打开
                    </span>
                  }
                  hintBelow="开启后，帖子与评论中的外链在新标签打开；关闭则当前页跳转。"
                >
                  <div className="flex items-center gap-2">
                    <AdminSwitch
                      checked={postLinkNewTab}
                      disabled={togglingLink}
                      onChange={() => void togglePostLinkNewTab()}
                      label="外链新标签打开"
                    />
                    <InstantNote saving={togglingLink} />
                  </div>
                </AdminSettingsRow>
              </AdminSettingsGroup>

              <AdminSettingsGroup
                title="附件与上传"
                description="限额停止输入约 0.5 秒后写入。扩展名白名单需点保存。"
                footer={
                  <AdminSettingsActions
                    dirty={extsDirty}
                    saving={savingExts}
                    saveLabel="保存扩展名"
                    saveDisabled={!extsDirty || savingExts || !extLimit}
                    onSave={() => void saveExts()}
                    onDiscard={() => setExts([...savedExts])}
                  />
                }
              >
                <AdminSettingsRow
                  label={
                    <span className="inline-flex items-center gap-1.5">
                      <Paperclip size={15} /> 附件单文件上限
                    </span>
                  }
                  hintBelow={
                    attMaxMB >= 50
                      ? "发帖附件体积上限。当前 ≥50MB：请确认服务器内存与反代 body 上限已同步调大。"
                      : "发帖附件体积上限。过大可能拖垮进程，反代与 Next 请求体上限须不少于该值。"
                  }
                >
                  <div className="flex flex-wrap items-center gap-2">
                    <AdminStepper
                      value={attMaxMB}
                      min={1}
                      max={999999}
                      unit="MB"
                      ariaLabel="附件单文件上限"
                      disabled={savingLimits}
                      onChange={(n) => {
                        setAttMaxMB(n);
                        scheduleLimitSave({ attachment_max_mb: n });
                      }}
                    />
                    <InstantNote saving={savingLimits} />
                  </div>
                </AdminSettingsRow>

                <AdminSettingsRow
                  label={
                    <span className="inline-flex items-center gap-1.5">
                      <Paperclip size={15} /> 每帖附件个数
                    </span>
                  }
                  hintBelow="单帖（含草稿）最多可绑定的附件数量。"
                >
                  <div className="flex flex-wrap items-center gap-2">
                    <AdminStepper
                      value={attMaxCount}
                      min={1}
                      max={20}
                      unit="个"
                      ariaLabel="每帖附件个数"
                      disabled={savingLimits}
                      onChange={(n) => {
                        setAttMaxCount(n);
                        scheduleLimitSave({ attachment_max_count: n });
                      }}
                    />
                    <InstantNote saving={savingLimits} />
                  </div>
                </AdminSettingsRow>

                <AdminSettingsRow
                  label={
                    <span className="inline-flex items-center gap-1.5">
                      <ImageIcon size={15} /> 正文插图上限
                    </span>
                  }
                  hintBelow={
                    imageMaxMB >= 10
                      ? "Markdown 拖拽/粘贴图片（仅 JPEG / PNG / WebP）。插图 ≥10MB 时解码更耗内存。"
                      : "Markdown 拖拽/粘贴图片（仅 JPEG / PNG / WebP）。"
                  }
                >
                  <div className="flex flex-wrap items-center gap-2">
                    <AdminStepper
                      value={imageMaxMB}
                      min={1}
                      max={999999}
                      unit="MB"
                      ariaLabel="正文插图上限"
                      disabled={savingLimits}
                      onChange={(n) => {
                        setImageMaxMB(n);
                        scheduleLimitSave({ image_max_mb: n });
                      }}
                    />
                    <InstantNote saving={savingLimits} />
                  </div>
                </AdminSettingsRow>

                <AdminSettingsRow
                  label={
                    <span className="inline-flex items-center gap-1.5">
                      <Paperclip size={15} /> 限制附件扩展名
                    </span>
                  }
                  hintBelow={
                    extLimit
                      ? "仅允许下方列表中的扩展名。"
                      : "任意格式可传，仍受体积上限与下载沙箱约束。"
                  }
                >
                  <div className="flex items-center gap-2">
                    <AdminSwitch
                      checked={extLimit}
                      disabled={togglingExtLimit}
                      onChange={() => void toggleExtLimit()}
                      label="限制附件扩展名"
                    />
                    <InstantNote saving={togglingExtLimit} />
                  </div>
                </AdminSettingsRow>

                <AdminSettingsRow label="允许的扩展名" hintBelow="列表变更需点保存，不会随开关立即写入。" wide>
                  <div className="admin-settings-control-long">
                    <AdminExtChipEditor value={exts} onChange={setExts} disabled={!extLimit || savingExts} />
                  </div>
                </AdminSettingsRow>
              </AdminSettingsGroup>
            </>
          )}

          {active === "gitimport" && (
            <AdminSettingsGroup
              className="is-fill"
              title="提交导入适配器"
              description="用 JSON 描述 GitHub / Gitea 等匹配规则。保存时服务端会做结构校验，不会执行任意代码。"
              footer={
                <>
                  <AdminSettingsActions
                    dirty={gitImportDirty}
                    saving={savingGitImport}
                    saveLabel="保存导入适配器"
                    onSave={() => void saveGitImport()}
                    onDiscard={() => {
                      setGitImportJSON(savedGitImport);
                      setGitValidateMsg(null);
                    }}
                  >
                    <button
                      type="button"
                      className="btn btn-line btn-sm"
                      disabled={gitImportLoading || savingGitImport}
                      onClick={() => {
                        if (validateGitImportClient()) toast("语法校验通过", "ok");
                        else toast("JSON 语法无效");
                      }}
                    >
                      <CheckCircle2 size={14} /> 校验
                    </button>
                    <button
                      type="button"
                      className="btn btn-line btn-sm"
                      disabled={savingGitImport}
                      onClick={() => setRestoreGitOpen(true)}
                    >
                      <RotateCcw size={14} /> 恢复默认
                    </button>
                  </AdminSettingsActions>
                  {(gitPreview || gitImportLoaded) ? (
                    <div className="admin-settings-git-summary" aria-label="规则摘要">
                      <span className="admin-settings-git-summary-kicker">规则摘要</span>
                      {gitPreview ? (
                        <>
                          <span>
                            最多 {gitPreview.maxPages ?? "—"} 页 · {gitPreview.maxCommits ?? "—"} 条提交
                          </span>
                          {gitPreview.sources.map((s) => (
                            <span key={`${s.id}-${s.host}`} className="admin-settings-git-summary-src">
                              <GitBranch size={12} aria-hidden />
                              <strong>{s.id}</strong>
                              <span>{s.host}</span>
                            </span>
                          ))}
                        </>
                      ) : (
                        <span>JSON 无法解析时不显示摘要，保存前请先校验语法。</span>
                      )}
                    </div>
                  ) : null}
                </>
              }
            >
              {gitImportLoading && !gitImportLoaded ? (
                <div className="flex items-center gap-2 meta py-8 justify-center">
                  <Loader2 size={16} className="animate-spin" /> 加载适配器…
                </div>
              ) : (
                <AdminSettingsRow
                  className="admin-settings-git-editor"
                  label="适配器 JSON"
                  htmlFor="git-import-json"
                  hint="声明式匹配规则。服务端只按规则拉取。"
                  wide
                >
                  <div className="admin-settings-git-json-wrap">
                    <textarea
                      id="git-import-json"
                      className="j13-compose-field admin-settings-git-json font-mono text-[12.5px] leading-relaxed"
                      spellCheck={false}
                      value={gitImportJSON}
                      onChange={(e) => {
                        setGitImportJSON(e.target.value);
                        setGitValidateMsg(null);
                      }}
                      placeholder="粘贴或编辑适配器 JSON…"
                    />
                    {gitValidateMsg ? (
                      <p
                        className={`mt-2 text-[12.5px] flex items-start gap-1.5 ${
                          gitValidateMsg.ok ? "" : "alert-error !mt-2"
                        }`}
                        style={gitValidateMsg.ok ? { color: "var(--ok, #137333)" } : undefined}
                        role="status"
                      >
                        {gitValidateMsg.ok ? <CheckCircle2 size={14} className="mt-0.5 shrink-0" /> : null}
                        {gitValidateMsg.text}
                      </p>
                    ) : null}
                  </div>
                </AdminSettingsRow>
              )}
            </AdminSettingsGroup>
          )}
        </div>
      </AdminSettingsWork>

      <ConfirmDialog
        open={restoreGitOpen}
        title="恢复默认适配器"
        message="将覆盖当前「提交导入」JSON 为内置 GitHub + Gitea 模板，并立即保存。确定继续？"
        busy={savingGitImport}
        confirmLabel="恢复并保存"
        onCancel={() => !savingGitImport && setRestoreGitOpen(false)}
        onConfirm={() => void restoreGitDefault()}
      />
      <ConfirmDialog
        open={leaveOpen}
        title="有未保存的修改"
        message="离开后，当前保存单元里尚未写入的修改会丢失。确定离开？"
        confirmLabel="离开"
        danger
        onCancel={cancelLeave}
        onConfirm={confirmLeave}
      />
    </AdminSettingsPage>
  );
}