sitemap.ts

import type { MetadataRoute } from "next";
import { getAllPosts, getAllTags, tagToSlug } from "@/lib/blog";
import { SITE } from "@/lib/site";

// Static surface — landing + docs + blog index. Per-post and per-tag entries
// are appended below from the MDX frontmatter / tag list.
const STATIC_ROUTES: Array<{
  path: string;
  changeFrequency: MetadataRoute.Sitemap[number]["changeFrequency"];
  priority: number;
}> = [
  { path: "/", changeFrequency: "weekly", priority: 1.0 },
  { path: "/docs", changeFrequency: "weekly", priority: 0.9 },
  { path: "/playground", changeFrequency: "monthly", priority: 0.8 },
  { path: "/blog", changeFrequency: "weekly", priority: 0.8 },
  { path: "/examples", changeFrequency: "monthly", priority: 0.7 },
];

export default function sitemap(): MetadataRoute.Sitemap {
  const now = new Date();
  const posts = getAllPosts();
  const tags = getAllTags();

  const staticEntries = STATIC_ROUTES.map(
    ({ path, changeFrequency, priority }) => ({
      url: `${SITE.url}${path === "/" ? "" : path}`,
      lastModified: now,
      changeFrequency,
      priority,
    }),
  );

  const postEntries: MetadataRoute.Sitemap = posts.map((post) => ({
    url: `${SITE.url}/blog/${post.slug}`,
    lastModified: new Date(
      post.frontmatter.updatedAt ?? post.frontmatter.publishedAt,
    ),
    changeFrequency: "monthly",
    priority: 0.7,
  }));

  const tagEntries: MetadataRoute.Sitemap = tags.map(({ tag }) => ({
    url: `${SITE.url}/blog/tags/${tagToSlug(tag)}`,
    lastModified: now,
    changeFrequency: "monthly",
    priority: 0.5,
  }));

  return [...staticEntries, ...postEntries, ...tagEntries];
}