"use client";

import type { ReactNode } from "react";
import { useState } from "react";
import Link from "next/link";
import { usePathname } from "next/navigation";
import { AnimatePresence, motion } from "motion/react";
import { Logomark } from "@/components/logomark";
import { HexMark, HoneycombPattern } from "@/components/honeycomb";
import { AdminCommandPalette, type PaletteEntry } from "@/components/admin-command-palette";
import { useI18n } from "@/i18n/i18n-provider";
import type { Dictionary } from "@/i18n/dictionary-type";
import { ThemeToggle } from "@/components/theme-toggle";
import type { ThemeChoice } from "@/lib/theme";

/** Was an einer Seite gerade auf Bearbeitung wartet (Zaehler in der Seitenleiste). */
export type AdminBadges = Partial<Record<string, number>>;

interface NavItem {
  href: string;
  label: string;
}

/**
 * Gruppiert statt einer langen Liste: 13 Eintraege lesen sich in vier
 * kurzen Bloecken schneller, und die taegliche Arbeit (Verkauf) steht oben.
 */
function getAdminNavGroups(t: Dictionary): { label: string | null; items: NavItem[] }[] {
  return [
    { label: null, items: [{ href: "/admin", label: t.adminShell.navDashboard }] },
    {
      label: t.adminShell.groupSales,
      items: [
        { href: "/admin/bestellungen", label: t.adminShell.navOrders },
        { href: "/admin/retouren", label: t.adminShell.navReturns },
        { href: "/admin/widerrufe", label: t.adminShell.navWithdrawals },
        { href: "/admin/gutscheine", label: t.adminShell.navVouchers },
        { href: "/admin/versand", label: t.adminShell.navShipping },
      ],
    },
    {
      label: t.adminShell.groupRange,
      items: [
        { href: "/admin/produkte", label: t.adminShell.navProducts },
        { href: "/admin/ernten", label: t.adminShell.navHarvests },
        { href: "/admin/chargen", label: t.adminShell.navBatches },
        { href: "/admin/bewertungen", label: t.adminShell.navReviews },
      ],
    },
    {
      label: t.adminShell.groupCustomers,
      items: [
        { href: "/admin/benutzer", label: t.adminShell.navUsers },
        { href: "/admin/anfragen", label: t.adminShell.navBusinessInquiries },
      ],
    },
    {
      label: t.adminShell.groupSite,
      items: [
        { href: "/admin/einstellungen", label: t.adminShell.navContent },
        { href: "/admin/audit-log", label: t.adminShell.navAuditLog },
      ],
    },
  ];
}

function getPaletteEntries(t: Dictionary): PaletteEntry[] {
  const pages = getAdminNavGroups(t).flatMap((group) =>
    group.items.map((item) => ({ ...item, section: "pages" as const }))
  );
  const actions: PaletteEntry[] = [
    { href: "/admin/produkte/neu", label: t.adminShell.actionNewProduct, section: "actions" },
    { href: "/admin/gutscheine/neu", label: t.adminShell.actionNewVoucher, section: "actions" },
    { href: "/admin/benutzer/neu", label: t.adminShell.actionNewUser, section: "actions" },
    { href: "/admin/versand/neu", label: t.adminShell.actionNewShippingTier, section: "actions" },
    { href: "/shop", label: t.adminShell.actionViewShop, section: "actions" },
  ];
  return [...pages, ...actions];
}

function isActiveHref(pathname: string, href: string): boolean {
  if (href === "/admin") return pathname === "/admin";
  return pathname === href || pathname.startsWith(`${href}/`);
}

function NavLinks({
  pathname,
  groups,
  badges,
  onNavigate,
  waitingLabel,
}: {
  pathname: string;
  groups: ReturnType<typeof getAdminNavGroups>;
  badges: AdminBadges;
  onNavigate?: () => void;
  waitingLabel: (count: number) => string;
}) {
  return (
    <>
      {groups.map((group, groupIndex) => (
        <div key={group.label ?? groupIndex} className={groupIndex > 0 ? "mt-5" : ""}>
          {group.label ? (
            <p className="px-5 pb-1.5 text-[10px] tracking-wide-caps text-cream/40">{group.label}</p>
          ) : null}
          {group.items.map((item) => {
            const active = isActiveHref(pathname, item.href);
            const count = badges[item.href] ?? 0;
            return (
              <Link
                key={item.href}
                href={item.href}
                onClick={onNavigate}
                aria-current={active ? "page" : undefined}
                className={`group relative flex items-center gap-3 px-5 py-2 text-sm transition-colors ${
                  active ? "text-cream" : "text-cream/70 hover:text-cream"
                }`}
              >
                {/* Aktive Seite als weich einblendende Flaeche, die beim
                    Wechsel zur neuen Seite hinueberwandert. */}
                {active ? (
                  <motion.span
                    layoutId="admin-nav-active"
                    className="absolute inset-y-0.5 left-2 right-2 -z-10 bg-surface/10"
                    transition={{ type: "spring", stiffness: 420, damping: 36 }}
                  />
                ) : null}
                <HexMark
                  filled={active}
                  className={`h-2.5 w-2.5 flex-shrink-0 transition-[color,transform] duration-300 ${
                    active ? "text-honey-light" : "text-cream/25 group-hover:text-cream/60 group-hover:rotate-90"
                  }`}
                />
                <span className="flex-1">{item.label}</span>
                {count > 0 ? (
                  <span
                    className="min-w-5 rounded-full bg-honey-deep px-1.5 text-center text-[11px] leading-5 text-cream tabular-nums"
                    title={waitingLabel(count)}
                  >
                    <span aria-hidden="true">{count}</span>
                    <span className="sr-only">{waitingLabel(count)}</span>
                  </span>
                ) : null}
              </Link>
            );
          })}
        </div>
      ))}
    </>
  );
}

function Wordmark({ logoSrc }: { logoSrc: string | null }) {
  return (
    <Link href="/admin" className="flex items-center gap-2">
      <Logomark className="h-7 w-7 flex-shrink-0" variant="inverted" src={logoSrc} />
      <span className="tracking-[0.15em] text-xs whitespace-nowrap">WABENHAIN ADMIN</span>
    </Link>
  );
}

function PaletteTrigger({ onClick, label, shortcut }: { onClick: () => void; label: string; shortcut: string }) {
  return (
    <button
      type="button"
      onClick={onClick}
      className="mx-3 flex w-[calc(100%-1.5rem)] items-center gap-2 border border-cream/15 px-3 py-2 text-left text-xs text-cream/60 transition-colors hover:border-cream/35 hover:text-cream"
    >
      <svg viewBox="0 0 24 24" className="h-3.5 w-3.5" fill="none" stroke="currentColor" strokeWidth="1.6" aria-hidden="true">
        <circle cx="11" cy="11" r="6.5" />
        <path d="m16 16 4.5 4.5" strokeLinecap="round" />
      </svg>
      <span className="flex-1">{label}</span>
      <kbd className="border border-cream/20 px-1 text-[10px] text-cream/50">{shortcut}</kbd>
    </button>
  );
}

interface AdminShellProps {
  adminName: string;
  /** Gewaehlte Darstellung (Cookie), siehe lib/theme.ts. */
  themeChoice?: ThemeChoice;
  /** Logo fuer dunkle Flaechen, siehe lib/brand.ts. */
  logoSrc?: string | null;
  badges?: AdminBadges;
  logoutAction: () => void | Promise<void>;
  children: ReactNode;
}

/**
 * Eigener Arbeitsbereich fuer die Imkerei: gruppierte Seitenleiste mit
 * Zaehlern fuer alles, was gerade wartet, und einer Schnellsuche (Strg/Cmd+K).
 * Ab lg persistente Seitenleiste links, darunter ein Vollbild-Menue nach
 * demselben Muster wie die mobile Hauptnavigation in site-chrome.tsx. Die
 * Shop-Kopf- und -Fusszeile blendet das Root-Layout hier aus
 * (components/hide-on-admin.tsx).
 */
export function AdminShell({
  adminName,
  logoSrc = null,
  themeChoice = "system",
  badges = {},
  logoutAction,
  children,
}: AdminShellProps) {
  const { t } = useI18n();
  const groups = getAdminNavGroups(t);
  const pathname = usePathname();
  const [mobileOpen, setMobileOpen] = useState(false);
  const [paletteOpen, setPaletteOpen] = useState(false);

  const paletteLabels = {
    placeholder: t.adminShell.palettePlaceholder,
    noResults: t.adminShell.paletteNoResults,
    pages: t.adminShell.paletteSectionPages,
    actions: t.adminShell.paletteSectionActions,
    dialog: t.adminShell.paletteOpen,
  };

  const footer = (
    <div className="px-5 py-4 border-t border-cream/10">
      {/* Der Shop-Kopf ist im Admin ausgeblendet (HideOnAdmin) — ohne diesen
          Link fuehrte kein Weg zurueck auf die Website. */}
      <div className="mb-4 flex items-center justify-between gap-3">
      <Link
        href="/"
        className="group inline-flex items-center gap-2 py-1 text-sm text-cream/90 hover:text-cream"
      >
        <svg
          width="14"
          height="14"
          viewBox="0 0 24 24"
          fill="none"
          stroke="currentColor"
          strokeWidth="1.75"
          aria-hidden="true"
          className="transition-transform duration-300 ease-[var(--ease-arrive)] group-hover:-translate-x-0.5 motion-reduce:transition-none"
        >
          <path d="M15 6l-6 6 6 6" />
        </svg>
        <span className="link-draw">{t.adminShell.backToWebsite}</span>
      </Link>
      <ThemeToggle initial={themeChoice} className="-mr-2 text-cream/70 hover:text-cream" />
      </div>
      <p className="text-xs text-cream/60 truncate">{t.adminShell.loggedInAs(adminName)}</p>
      <form action={logoutAction} className="mt-2">
        <button type="submit" className="text-xs text-cream/80 underline hover:text-cream">
          {t.adminShell.logout}
        </button>
      </form>
    </div>
  );

  return (
    <div className="min-h-screen bg-surface/40 lg:flex">
      <aside className="relative isolate hidden overflow-hidden lg:flex lg:flex-col lg:w-64 lg:shrink-0 lg:sticky lg:top-0 lg:h-screen bg-forest text-cream">
        <HoneycombPattern className="-z-10 text-honey-light/[0.06]" size={18} fade="bottom" />
        <div className="flex items-center h-16 px-5 border-b border-cream/10">
          <Wordmark logoSrc={logoSrc} />
        </div>
        <div className="pt-4">
          <PaletteTrigger
            onClick={() => setPaletteOpen(true)}
            label={t.adminShell.paletteOpen}
            shortcut={t.adminShell.paletteShortcut}
          />
        </div>
        <nav aria-label={t.adminShell.navAriaLabel} className="relative isolate flex-1 overflow-y-auto py-4">
          <NavLinks pathname={pathname} groups={groups} badges={badges} waitingLabel={t.adminShell.badgeWaiting} />
        </nav>
        {footer}
      </aside>

      <div className="flex-1 min-w-0">
        <header className="lg:hidden sticky top-0 z-30 bg-forest text-cream flex items-center justify-between h-16 px-5">
          <Wordmark logoSrc={logoSrc} />
          <div className="flex items-center gap-1">
            <button
              aria-label={t.adminShell.paletteOpen}
              className="w-10 h-10 flex items-center justify-center"
              onClick={() => setPaletteOpen(true)}
            >
              <svg width="18" height="18" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="1.5">
                <circle cx="11" cy="11" r="6.5" />
                <path d="m16 16 4.5 4.5" />
              </svg>
            </button>
            <button
              aria-label={t.adminShell.openMenu}
              className="w-10 h-10 flex items-center justify-center flex-shrink-0"
              onClick={() => setMobileOpen(true)}
            >
              <svg width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="1.5">
                <path d="M3 6h18M3 12h18M3 18h18" />
              </svg>
            </button>
          </div>
        </header>

        {/* Kein zweites <main>: das Root-Layout stellt bereits eines. */}
        <div className="admin-content max-w-6xl mx-auto px-6 py-10 overflow-x-hidden">{children}</div>
      </div>

      <AnimatePresence>
        {mobileOpen ? (
          <motion.div
            initial={{ opacity: 0 }}
            animate={{ opacity: 1 }}
            exit={{ opacity: 0 }}
            transition={{ duration: 0.2 }}
            className="lg:hidden fixed inset-0 z-50 bg-forest text-cream flex flex-col"
          >
            <div className="flex items-center justify-between h-16 px-5 border-b border-cream/10 flex-shrink-0">
              <Wordmark logoSrc={logoSrc} />
              <button
                aria-label={t.adminShell.closeMenu}
                className="w-10 h-10 flex items-center justify-center flex-shrink-0"
                onClick={() => setMobileOpen(false)}
              >
                <svg width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="1.5">
                  <path d="M6 6l12 12M18 6L6 18" />
                </svg>
              </button>
            </div>
            <nav aria-label={t.adminShell.mobileNavAriaLabel} className="relative isolate flex-1 overflow-y-auto py-4">
              <NavLinks
                pathname={pathname}
                groups={groups}
                badges={badges}
                waitingLabel={t.adminShell.badgeWaiting}
                onNavigate={() => setMobileOpen(false)}
              />
            </nav>
            {footer}
          </motion.div>
        ) : null}
      </AnimatePresence>

      <AdminCommandPalette
        entries={getPaletteEntries(t)}
        labels={paletteLabels}
        open={paletteOpen}
        onOpenChange={setPaletteOpen}
      />
    </div>
  );
}