import fs from "fs";

import parse from "../lib/markdown.mjs";

import MDXPage from "../components/MDXPage";
import clientPromise from "@/lib/mddb";
import { getAuthorsDetails } from "lib/getAuthorsDetails";
import Layout from "components/Layout";

export default function DRDPage({ source, frontMatter }) {
  source = JSON.parse(source);
  frontMatter = JSON.parse(frontMatter);

  return (
    <Layout title={frontMatter.title}>
      <MDXPage source={source} frontMatter={frontMatter} />
    </Layout>
  );
}

export const getStaticProps = async ({ params }) => {
  const urlPath = params.slug ? params.slug.join("/") : "";

  const mddb = await clientPromise;
  const dbFile = await mddb.getFileByUrl(urlPath);

  const dbBacklinks = await mddb.getLinks({
    fileId: dbFile._id,
    direction: "backward",
  });
  // TODO temporary solution, we will have a method on MddbFile to get these links
  const dbBacklinkFilesPromises = dbBacklinks.map((link) =>
    mddb.getFileById(link.from)
  );
  const dbBacklinkFiles = await Promise.all(dbBacklinkFilesPromises);
  const dbBacklinkUrls = dbBacklinkFiles.map(
    (file) => file.toObject().url_path
  );

  // TODO we can already get frontmatter from dbFile.metadata
  // so parse could only return mdxSource
  const source = fs.readFileSync(dbFile.file_path, { encoding: "utf-8" });
  const { mdxSource, frontMatter } = await parse(source, "mdx", {
    backlinks: dbBacklinkUrls,
  });

  // Temporary, so that blogs work properly
  if (dbFile.url_path.startsWith("blog/")) {
    frontMatter.layout = "blog";
    frontMatter.authorsDetails = await getAuthorsDetails(
      dbFile.metadata.authors
    );
  }

  return {
    props: {
      source: JSON.stringify(mdxSource),
      frontMatter: JSON.stringify(frontMatter),
    },
  };
};

export async function getStaticPaths() {
  const mddb = await clientPromise;
  const allDocuments = await mddb.getFiles({ extensions: ["md", "mdx"] });

  const paths = allDocuments.map((page) => {
    const parts = page.url_path.split("/");
    return { params: { slug: parts } };
  });

  return {
    paths,
    fallback: false,
  };
}