"use client";

import { ReactNode, useEffect, useRef, useState } from "react";
import Link from "next/link";
import { usePathname, useRouter } from "next/navigation";
import { Hexagon } from "lucide-react";
import { useAuth } from "@/lib/auth/auth-context";
import { finishHandOvers, purgeStaleDraftPhotos } from "@/lib/photos/store";
import { LogoutConfirmDialog } from "@/components/auth/logout-confirm-dialog";
import { NotificationBell } from "@/components/notification-bell";
import { OfflineBand } from "@/components/offline/offline-band";
import { UserAvatar } from "@/components/user-avatar";
import {
  DropdownMenu,
  DropdownMenuContent,
  DropdownMenuGroup,
  DropdownMenuItem,
  DropdownMenuLabel,
  DropdownMenuSeparator,
  DropdownMenuTrigger,
} from "@/components/ui/dropdown-menu";
import { Sidebar } from "./sidebar";
import { BottomNav } from "./bottom-nav";
import { hasQuickAddButton, QuickAddSheet } from "./quick-add-sheet";
import { PageTransition } from "./page-transition";

/** Id of the page content, the target of the skip link. */
const MAIN_CONTENT_ID = "main-content";

export default function AppLayout({ children }: { children: ReactNode }) {
  const router = useRouter();
  const pathname = usePathname();
  const { user, isLoading, sessionMode } = useAuth();
  const [isLogoutOpen, setIsLogoutOpen] = useState(false);
  // Focus lands here when the offline queue sheet closes and nothing else is left.
  const pageContentRef = useRef<HTMLDivElement>(null);

  useEffect(() => {
    if (!isLoading && !user) {
      router.replace("/login");
    }
  }, [isLoading, user, router]);

  // Photos of form drafts nobody can restore any more (older than 3 days)
  // leave the device. Housekeeping only: if it fails, the next start tries again.
  useEffect(() => {
    void purgeStaleDraftPhotos(Date.now()).catch(() => undefined);
  }, []);

  // Online saves whose photos could not be tied to their inspection at once:
  // finished for the signed-in user, even offline - the photos then wait as
  // entries of their own. Every sync run of that user tries again too.
  const userId = user?.id;
  useEffect(() => {
    if (userId) {
      void finishHandOvers(userId).catch(() => undefined);
    }
  }, [userId]);

  if (isLoading || !user) {
    return null;
  }

  // The phone's quick-add button floats 16 px above the bottom nav and is
  // 48 px high: without room under the page it would cover the last buttons.
  const contentPaddingClass = hasQuickAddButton(pathname, user.permissions)
    ? "pb-[calc(var(--bottom-nav-height)+--spacing(18))]"
    : "pb-(--bottom-nav-height)";

  // The page scrolls on the window. No ancestor of the page content may be a
  // scroll container (overflow auto/scroll/hidden): it would capture
  // `position: sticky` and the StickySubmit save bar would never stick.
  return (
    <div className="flex min-h-screen pr-(--safe-area-right) pl-(--safe-area-left)">
      <a
        href={`#${MAIN_CONTENT_ID}`}
        onClick={(event) => {
          // The hash alone would not move the focus into a Next.js page reliably.
          event.preventDefault();
          pageContentRef.current?.focus();
          pageContentRef.current?.scrollIntoView?.({ block: "start" });
        }}
        className="sr-only focus:not-sr-only focus:fixed focus:top-2 focus:left-2 focus:z-50 focus:rounded-lg focus:bg-card focus:px-4 focus:py-3 focus:text-sm focus:font-medium focus:shadow-[var(--shadow-elevated)] focus:ring-3 focus:ring-ring/50 focus:outline-none"
      >
        Zum Inhalt springen
      </a>
      <Sidebar user={user} />
      <div className="flex min-w-0 flex-1 flex-col">
        <header className="sticky top-0 z-10 flex items-center justify-between gap-3 bg-card/85 px-4 py-3 shadow-[var(--shadow-soft)] backdrop-blur-md sm:justify-end sm:px-6">
          <Link
            href="/dashboard"
            className="flex items-center gap-1.5 font-heading font-semibold sm:hidden"
          >
            <span
              className="flex size-7 items-center justify-center rounded-lg"
              style={{ background: "var(--gradient-honey)" }}
            >
              <Hexagon className="size-4 fill-white/25 text-white" strokeWidth={2.25} />
            </span>
            ApiCore
          </Link>
          <div className="flex shrink-0 items-center gap-2 text-sm">
            <QuickAddSheet user={user} variant="header" />
            <NotificationBell />
            <DropdownMenu>
              <DropdownMenuTrigger className="rounded-full" aria-label="Konto-Menü">
                <UserAvatar name={user.name} hasAvatar={user.hasAvatar} size="sm" />
              </DropdownMenuTrigger>
              <DropdownMenuContent align="end">
                <DropdownMenuGroup>
                  <DropdownMenuLabel className="max-w-48 truncate font-normal text-muted-foreground">
                    {user.email}
                  </DropdownMenuLabel>
                </DropdownMenuGroup>
                <DropdownMenuSeparator />
                <DropdownMenuItem render={<Link href="/profile" />}>
                  Profil
                </DropdownMenuItem>
                <DropdownMenuItem render={<Link href="/settings/voice" />}>
                  Sprache &amp; Datenschutz
                </DropdownMenuItem>
                <DropdownMenuItem
                  variant="destructive"
                  onClick={() => setIsLogoutOpen(true)}
                >
                  Abmelden
                </DropdownMenuItem>
              </DropdownMenuContent>
            </DropdownMenu>
          </div>
        </header>
        <OfflineBand
          userId={user.id}
          pageContentRef={pageContentRef}
          syncEnabled={sessionMode === "online"}
        />
        <div
          id={MAIN_CONTENT_ID}
          ref={pageContentRef}
          tabIndex={-1}
          className={`flex-1 ${contentPaddingClass} outline-none sm:pb-(--safe-area-bottom)`}
        >
          <PageTransition>{children}</PageTransition>
        </div>
      </div>
      <BottomNav user={user} />
      <QuickAddSheet user={user} variant="fab" />
      <LogoutConfirmDialog
        open={isLogoutOpen}
        onOpenChange={setIsLogoutOpen}
        userId={user.id}
        onLoggedOut={() => router.push("/login")}
      />
    </div>
  );
}