import { notFound } from "next/navigation";
import Layout from "@/components/layout/StLayout";
import SpecialtyDetailPage from "@/components/specialties/detail";
import specialtiesData from "@/data/specialties.json";
import { getStateInfo } from "@/lib/getStateInfo";
import { getRequestOrigin } from "@/lib/getCanonicalUrl";
import { resolveCityDisplayName } from "@/lib/domainHelpers";
import { buildSpecialtyFaq, buildSpecialtyIntro } from "@/lib/specialtyContent";
import { safeJsonLd } from "@/lib/sanitize";
import { fetchReq } from "@/lib/req";

const API_URL = process.env.NEXT_PUBLIC_API_URL;
const DOCTOR_LIMIT = 12;

const findSpecialty = (slug) =>
  specialtiesData.find((item) => item.slug === slug && item.status === 1) ?? null;

// روی هر دامنهٔ شهری این صفحه خودکار «تخصص + همان شهر» است — شهر از host می‌آید.
async function getDoctors(specialtyId, cityId) {
  try {
    const res = await fetchReq(`${API_URL}/api/v1/doctors`, {
      params: {
        specialty_id: specialtyId,
        ...(cityId && { city_id: cityId }),
        page: 1,
        limit: DOCTOR_LIMIT,
      },
    });
    return {
      items: res?.data?.data ?? res?.data ?? [],
      total: Number(res?.data?.meta?.totalRecords ?? res?.meta?.totalRecords ?? 0),
    };
  } catch {
    return { items: [], total: 0 };
  }
}

export async function generateMetadata({ params }) {
  const { slug } = await params;
  const specialty = findSpecialty(slug);
  if (!specialty) notFound();

  const { matchedCity, isRoot } = await getStateInfo();
  const siteName = matchedCity?.site_name || "نوبت 724";
  const cityName = resolveCityDisplayName(isRoot ? null : matchedCity);

  const title = `متخصص ${specialty.name} در ${cityName} | رزرو نوبت آنلاین | ${siteName}`;
  const description = `لیست بهترین پزشکان ${specialty.name} در ${cityName} همراه با نشانی مطب، ساعات کاری و امتیاز بیماران. رزرو نوبت آنلاین متخصص ${specialty.name}.`;
  const image = "/assets/images/og-image.png";

  return {
    title,
    description,
    // C1-a — صفحهٔ فرود تخصص per-domain است؛ canonical لایهٔ layout (self) درست است.
    openGraph: { title, description, images: [image] },
    twitter: { card: "summary_large_image", title, description, images: [image] },
  };
}

async function SpecialtyDetail({ params }) {
  const { slug } = await params;
  const specialty = findSpecialty(slug);
  if (!specialty) notFound();

  const { matchedCity, isRoot } = await getStateInfo();
  const origin = await getRequestOrigin();
  const cityName = resolveCityDisplayName(isRoot ? null : matchedCity);

  const { items: doctors, total } = await getDoctors(
    specialty.id,
    isRoot ? null : matchedCity?.id
  );

  const intro = buildSpecialtyIntro(specialty.name, cityName, total);
  const faq = buildSpecialtyFaq(specialty.name, cityName, total);
  const pageUrl = `${origin}/specialties/${specialty.slug}`;

  const pageJsonLd = {
    "@context": "https://schema.org",
    "@type": "MedicalWebPage",
    "@id": `${pageUrl}#webpage`,
    url: pageUrl,
    name: `متخصص ${specialty.name} در ${cityName}`,
    description: intro.slice(0, 300),
    about: { "@type": "MedicalSpecialty", name: specialty.name },
    ...(doctors.length > 0 && {
      mainEntity: {
        "@type": "ItemList",
        numberOfItems: doctors.length,
        itemListElement: doctors.map((doctor, idx) => ({
          "@type": "ListItem",
          position: idx + 1,
          url: `${origin}/doctor/${doctor.uuid}`,
          name: doctor.name,
        })),
      },
    }),
  };

  // FAQPage عمداً یک script مستقل است تا اسکیماهای موجود صفحه را نشکند.
  const faqJsonLd = {
    "@context": "https://schema.org",
    "@type": "FAQPage",
    mainEntity: faq.map((item) => ({
      "@type": "Question",
      name: item.question,
      acceptedAnswer: { "@type": "Answer", text: item.answer },
    })),
  };

  return (
    <>
      <script
        type="application/ld+json"
        dangerouslySetInnerHTML={{ __html: safeJsonLd(pageJsonLd) }}
      />
      <script
        type="application/ld+json"
        dangerouslySetInnerHTML={{ __html: safeJsonLd(faqJsonLd) }}
      />
      <Layout name="/specialties">
        <SpecialtyDetailPage
          specialtyName={specialty.name}
          cityName={cityName}
          doctors={doctors}
          intro={intro}
          faq={faq}
          origin={origin}
        />
      </Layout>
    </>
  );
}

export default SpecialtyDetail;