import type { Metadata } from "next";
import { notFound } from "next/navigation";
import { getPostBySlug, getPublishedPosts } from "@/lib/store";
import PostContent from "@/components/PostContent";

const SITE_URL = process.env.NEXT_PUBLIC_SITE_URL || "https://asui.xyz";

export async function generateStaticParams() {
  const posts = await getPublishedPosts();
  return posts.map((post) => ({ slug: post.slug }));
}

export async function generateMetadata({
  params,
}: {
  params: Promise<{ slug: string }>;
}): Promise<Metadata> {
  const { slug } = await params;
  const post = await getPostBySlug(slug);
  if (!post) return {};

  const url = `${SITE_URL}/posts/${post.slug}`;
  return {
    title: post.title,
    description: post.excerpt,
    alternates: { canonical: url },
    openGraph: {
      title: post.title,
      description: post.excerpt,
      url,
      type: "article",
      publishedTime: post.date,
      authors: ["胡旭"],
      tags: post.tags,
      siteName: "随 · asui.xyz",
      locale: "zh_CN",
    },
    twitter: {
      card: "summary_large_image",
      title: post.title,
      description: post.excerpt,
    },
  };
}

export default async function PostPage({ params }: { params: Promise<{ slug: string }> }) {
  const { slug } = await params;
  const post = await getPostBySlug(slug);
  if (!post) notFound();

  const all = await getPublishedPosts();
  const currentIndex = all.findIndex((p) => p.slug === slug);
  const prevPost = currentIndex > 0 ? all[currentIndex - 1] : null;
  const nextPost = currentIndex < all.length - 1 ? all[currentIndex + 1] : null;

  // BlogPosting 结构化数据，利于搜索引擎富摘要
  const jsonLd = {
    "@context": "https://schema.org",
    "@type": "BlogPosting",
    headline: post.title,
    description: post.excerpt,
    datePublished: post.date,
    dateModified: post.updatedAt,
    author: { "@type": "Person", name: "胡旭", url: SITE_URL },
    publisher: { "@type": "Person", name: "胡旭" },
    mainEntityOfPage: `${SITE_URL}/posts/${post.slug}`,
    keywords: post.tags.join(", "),
  };

  return (
    <>
      <script type="application/ld+json" dangerouslySetInnerHTML={{ __html: JSON.stringify(jsonLd) }} />
      <PostContent post={post} prevPost={prevPost} nextPost={nextPost} />
    </>
  );
}