"use client";

// Gemeinsamer Kopfbereich für alle internen Seiten. Statt zweier
// getrennter Bereiche (Kantine/Verwaltung) gibt es eine Navigation:
// Admins sehen zusätzlich die Verwaltungs-Links, der aktive Punkt
// wird hervorgehoben. Ab "sm" die klassische einzeilige Navigation,
// darunter ein Hamburger-Menü mit denselben Links gestapelt.

import Link from "next/link";
import { usePathname } from "next/navigation";
import { useEffect, useState } from "react";
import type { Role } from "@/lib/types";
import { formatMessage } from "@/lib/i18n/shared";
import { useDict } from "@/components/i18n/LocaleProvider";
import LanguageSwitcher from "@/components/i18n/LanguageSwitcher";

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

export default function AppHeader({
  role,
  displayName,
}: {
  role: Role;
  displayName: string;
}) {
  const pathname = usePathname();
  const dict = useDict();
  const [suggestionCount, setSuggestionCount] = useState(0);
  const [mobileOpen, setMobileOpen] = useState(false);

  useEffect(() => {
    fetch("/api/dish-suggestions")
      .then((res) => (res.ok ? res.json() : []))
      .then((data) => setSuggestionCount(Array.isArray(data) ? data.length : 0))
      .catch(() => {});
  }, [pathname]);

  // Hamburger-Panel bei jeder Navigation automatisch schließen.
  useEffect(() => {
    setMobileOpen(false);
  }, [pathname]);

  const menuLinks: NavLink[] = [
    { href: "/intern", label: dict.header.weekPlan },
    { href: "/intern/essenszeiten", label: dict.header.sections },
    { href: "/intern/gerichte", label: dict.header.dishes },
    { href: "/intern/kennzeichnung", label: dict.header.labels },
    { href: "/intern/vorschlaege", label: dict.header.suggestions },
  ];
  const adminLinks: NavLink[] = [
    { href: "/admin", label: dict.header.users },
    { href: "/admin/design", label: dict.header.design },
    { href: "/admin/sprachen", label: dict.header.languages },
  ];

  const linkClass = (href: string) =>
    `rounded px-2 py-0.5 transition-colors hover:bg-white/10 ${
      pathname === href ? "bg-white/20 font-semibold" : "text-white/90"
    }`;

  // Von Desktop- und Mobile-Navigation gemeinsam genutzt, damit die
  // Vorschläge-Badge-Logik nicht doppelt gepflegt werden muss.
  function renderLinks(links: NavLink[]) {
    return links.map((l) => (
      <Link key={l.href} href={l.href} className={`relative ${linkClass(l.href)}`}>
        {l.label}
        {l.href === "/intern/vorschlaege" && suggestionCount > 0 && (
          <span
            className="absolute -top-1.5 -right-1.5 flex h-4 min-w-4 items-center justify-center rounded-full bg-[var(--c-del)] px-1 text-[10px] font-bold leading-none text-white"
            aria-label={formatMessage(dict.header.openSuggestions, {
              count: suggestionCount,
            })}
          >
            {suggestionCount}
          </span>
        )}
      </Link>
    ));
  }

  return (
    <header className="bg-[var(--c-primary-dark)] text-white">
      {/* Mobil (< "sm"): kompakte Kopfzeile mit Hamburger-Toggle */}
      <div className="sm:hidden flex items-center justify-between px-4 py-3">
        <span className="font-bold text-base">{dict.header.canteen}</span>
        <button
          type="button"
          className="p-1 -m-1"
          onClick={() => setMobileOpen((v) => !v)}
          aria-label={dict.header.menuToggle}
          aria-expanded={mobileOpen}
        >
          <svg
            xmlns="http://www.w3.org/2000/svg"
            viewBox="0 0 24 24"
            width="24"
            height="24"
            fill="none"
            stroke="currentColor"
            strokeWidth="2"
            strokeLinecap="round"
            aria-hidden="true"
          >
            {mobileOpen ? (
              <path d="M6 6l12 12M18 6L6 18" />
            ) : (
              <path d="M4 7h16M4 12h16M4 17h16" />
            )}
          </svg>
        </button>
      </div>

      {mobileOpen && (
        <div className="sm:hidden px-4 pb-4 flex flex-col gap-4 text-sm border-t border-white/10">
          <nav className="flex flex-col gap-1" aria-label={dict.header.menuGroup}>
            <span className="mt-3 text-xs uppercase tracking-wider text-white/50">
              {dict.header.menuGroup}
            </span>
            {renderLinks(menuLinks)}
          </nav>

          {role === "admin" && (
            <nav className="flex flex-col gap-1" aria-label={dict.header.adminGroup}>
              <span className="text-xs uppercase tracking-wider text-white/50">
                {dict.header.adminGroup}
              </span>
              {renderLinks(adminLinks)}
            </nav>
          )}

          <Link
            href="/"
            className="w-fit rounded px-2 py-0.5 text-white/70 hover:bg-white/10"
          >
            {dict.header.viewMenu}
          </Link>

          <div className="flex items-center gap-3 border-t border-white/10 pt-3">
            <LanguageSwitcher />
            <Link
              href="/konto"
              className={`rounded px-2 py-0.5 hover:bg-white/10 ${
                pathname === "/konto" ? "bg-white/20 font-semibold" : "text-white/80"
              }`}
            >
              {displayName}
            </Link>
          </div>

          <form action="/logout" method="post">
            <button type="submit" className="btn btn-del w-full">
              {dict.common.logout}
            </button>
          </form>
        </div>
      )}

      {/* Ab "sm": bisherige einzeilige Navigation */}
      <div className="hidden sm:flex max-w-[1600px] mx-auto w-full px-4 py-3 flex-wrap items-center gap-x-6 gap-y-2 text-sm">
        <span className="font-bold text-base">{dict.header.canteen}</span>

        <nav
          className="flex flex-wrap items-center gap-x-1 gap-y-1"
          aria-label={dict.header.menuGroup}
        >
          <span className="mr-1 text-xs uppercase tracking-wider text-white/50">
            {dict.header.menuGroup}
          </span>
          {renderLinks(menuLinks)}
        </nav>

        {role === "admin" && (
          <nav
            className="flex flex-wrap items-center gap-x-1 gap-y-1"
            aria-label={dict.header.adminGroup}
          >
            <span className="mr-1 text-xs uppercase tracking-wider text-white/50">
              {dict.header.adminGroup}
            </span>
            {renderLinks(adminLinks)}
          </nav>
        )}

        <Link
          href="/"
          className="rounded px-2 py-0.5 text-white/70 hover:bg-white/10"
        >
          {dict.header.viewMenu}
        </Link>

        <div className="ml-auto flex items-center gap-3">
          <LanguageSwitcher />
          <Link
            href="/konto"
            title={dict.header.myAccount}
            className={`rounded px-2 py-0.5 hover:bg-white/10 ${
              pathname === "/konto"
                ? "bg-white/20 font-semibold"
                : "text-white/80"
            }`}
          >
            {displayName}
          </Link>
          <form action="/logout" method="post">
            <button type="submit" className="btn btn-del">
              {dict.common.logout}
            </button>
          </form>
        </div>
      </div>
    </header>
  );
}