const fs = require("fs");
const jsdom = require("jsdom");
const fetch = require("node-fetch");
const { JSDOM } = jsdom;
const { window } = new JSDOM("");
global.window = window;
var showdown = require("showdown");
const converter = new showdown.Converter();
const libxmljs = require("libxmljs");

const MIRROR_URL = "http://mirror.csclub.uwaterloo.ca/csclub/";

try {
  fs.mkdirSync("./markdown-talks/");
} catch (e) {
  if (e.code !== "EEXIST") {
    throw e;
  }
}

const file = fs
  .readFileSync("../../media/index.xml", "utf8")
  .replace(/<!DOCTYPE.*>/, "");

const xml = libxmljs.parseHtml(file);
const talks = xml.find("//mediaitem");

(async () => {
  const all = await Promise.all(
    talks.map(async (talk, idx) => {
      const { filename, markdown } = await xml2md(talk, idx);

      await fs.promises.writeFile(`./markdown-talks/${filename}.md`, markdown);
    }),
  );

  console.log(all.length);

  process.exit(0);
})();

/**
 *
 * @param {libxmljs.Element} talk
 */
async function xml2md(talk, index) {
  const title = talk.attr("title").value();

  const abstract = talk
    .get("abstract")
    ?.childNodes()
    .reduce((str, node) => str + node.toString(), "")
    .trim();

  const presentors = talk
    .get("presentor")
    .childNodes()
    .toString()
    .split(",")
    .map((s) => s.trim());

  const thumbSmall = MIRROR_URL + talk.get("thumbnail").attr("file").value();

  /** @type{string | undefined} */
  let thumbLarge = thumbSmall.replace("-thumb-small", "-thumb-large");

  if (!(await resourceExists(thumbLarge))) {
    thumbLarge = undefined;
  }

  const links = talk
    .find("mediafile")
    .map((mf) => ({
      /** @type{string} */
      file: MIRROR_URL + mf.attr("file").value(),

      /** @type{string} */
      type: mf.attr("type").value(),

      /** @type{string | undefined} */
      size: mf.attr("size")?.value() ?? undefined,
    }))
    .map(
      ({ file, type, size }) =>
        "  " +
        `
  - file: '${file.replaceAll("'", "''")}'
    type: '${type.replaceAll("'", "''")}'
    ${size == null ? "" : `size: '${size.replaceAll("'", "''")}'`}
`.trim(),
    );

  const markdown =
    `
---
index: ${index}
title: '${title.replaceAll("'", "''")}'
presentors:
  - ${presentors.join("\n  - ").replaceAll("'", "''")}
thumbnails:
  small: '${thumbSmall}'${thumbLarge ? `\n  large: '${thumbLarge}'` : ""}
links:
${links.join("\n")}
---

${converter.makeMarkdown(abstract ?? "")}
`.trim() + "\n";

  return {
    filename: title
      .toLowerCase()
      .replaceAll(" ", "-")
      .replaceAll(":", "")
      .replaceAll("=", "")
      .replaceAll(",", "-")
      .replaceAll("'", "-")
      .replaceAll("+", "-plus-")
      .replaceAll(/-+/g, "-"),
    markdown,
  };
}

/**
 *
 * @param {string} url
 */
async function resourceExists(url) {

  const time = Math.trunc(Math.random() * 10000);
  await sleep(time);

  const timer = setTimeout(() => console.log("not done", time, url), time + 3000);
  const response = await fetch(url);

  clearTimeout(timer)

  return (
    response.status.toString().startsWith("2") ||
    response.status.toString().startsWith("3")
  );
}

function sleep(time) {
  return new Promise((resolve) => setTimeout(resolve, time));
}