server.js

const fs = require("fs");
const express = require("express");
const showdown = require("showdown");
const compression = require("compression");
const helmet = require("helmet");
const path = require("path");
const { parentPort } = require("worker_threads");

const StatManager = require("./stats_manager.js").StatManager;
const { log, dateFormatter } = require("./utilities.js");

// Statistics Manager
const StatMan = new StatManager("./data/stats.json");

const APP = express();
const PORT = process.env.PORT || 3000;
const STATMAN_INTERVAL = process.env.STATMAN_INTERVAL || 1000;

const BLOCKED_IMAGE_TYPES_FROM_REMOTE = ["jpg", "jpeg", "png", "gif", "bmp", "webp", "tiff", "tif", "heic", "heif", "avif", "ico", "jpe", "jp2", "jxr", "ras", "dds", "exr"];

// Markdown to HTML converter
const converter = new showdown.Converter({
  tables: true,
  tasklists: true,
  simpleLineBreaks: true,
  ghMentions: true,
  ghMentionsLink: "/{u}",
  openLinksInNewWindow: true,
  emoji: true,
  metadata: true,
});

// Set EmbeddedJS as view engine
APP.set("view engine", "ejs");

// Use compression
APP.use(compression());

// Set Content Security Policy Header
APP.use(
  helmet({
    contentSecurityPolicy: {
      directives: {
        defaultSrc: ["'self'"],
        styleSrc: ["'unsafe-inline'", "'self'"],
        fontSrc: ["'self'"],
        mediaSrc: ["'self'"],
        imgSrc: ["*"],
        scriptSrc: ["'unsafe-inline'", "'self'"],
      },
    },
  })
);

// Disable X-Powered-By header
APP.set("x-powered-by", false);

// Stat saver (also saves server resources :3)
let oldStats = StatMan.stats.global_visits;
setInterval(() => {
  if (StatMan.stats.global_visits != oldStats) {
    log(`%a[%lSTATMAN%a] [%b${dateFormatter(new Date())} UTC%a] %dSaved stats to disk.`);
    StatMan.writeStatsToDisk();
    oldStats = StatMan.stats.global_visits;
  }
}, STATMAN_INTERVAL);

// ----------------------------------------------

// Static files

APP.use(express.static(path.join(__dirname, "public")));

// let fontData = fs.readFileSync(__dirname + "/public/font.ttf");
// console.log("[LOAD] Loaded font file to memory.");

// APP.get("/font.ttf", (req, res) => {
//   res.setHeader("Cache-Control", "public, max-age=31557600");
//   res.send(fontData);
// });

// let faviconData = fs.readFileSync(__dirname + "/public/icon.ico");
// console.log("[LOAD] Loaded favicon file to memory.");

// APP.get("/favicon.ico", (req, res) => {
//   res.setHeader("Cache-Control", "public, max-age=31557600");
//   res.send(faviconData);
// });

// let bgData = fs.readFileSync(__dirname + "/public/bg.png");
// console.log("[LOAD] Loaded background image file to memory.");

// APP.get("/bg.png", (req, res) => {
//   res.setHeader("Cache-Control", "public, max-age=31557600");
//   res.send(bgData);
// });

// ----------------------------------------------

APP.get("/", (req, res) => {
  const users = fs.readdirSync(path.resolve(__dirname, "data", "users"));

  StatMan.incrementGlobalVisits();

  res.render("index", { users: users });
});

APP.get("/about", (req, res) => {
  StatMan.incrementGlobalVisits();

  const readmeContent = fs.readFileSync(path.resolve(__dirname, "README.md")).toString();

  let convertedData = converter.makeHtml(readmeContent);

  res.render("about", { data: convertedData });
});

APP.get("/random", (req, res) => {
  let posts = [];
  let user = "";

  while (posts.length == 0) {
    const users = fs.readdirSync(path.resolve(__dirname, "data", "users"));
    user = users[Math.floor(Math.random() * users.length)];
    posts = fs.readdirSync(path.resolve(__dirname, "data", "users", user, "posts"));
  }

  const post = posts[Math.floor(Math.random() * posts.length)].split(".")[0];

  res.redirect([user, post].join("/"));
});

APP.get("/stats", (req, res) => {
  StatMan.incrementGlobalVisits();

  res.render("stats", { stats: StatMan.stats });
});

APP.get("/:user", (req, res) => {
  if (!/^[A-Za-z0-9]+$/.test(req.params.user)) {
    res.status(404).render("error", { type: "user not found" });
    return;
  }

  let files = [];
  let about;

  try {
    files = fs.readdirSync(path.resolve(__dirname, "data", "users", req.params.user, "posts"));
  } catch {
    res.status(404).render("error", { type: "user not found" });
    return;
  }

  StatMan.incrementUser(req.params.user);
  StatMan.incrementGlobalVisits();

  try {
    let d = fs.readFileSync(path.resolve(__dirname, "data", "users", req.params.user, "about.md")).toString();
    about = converter.makeHtml(d);
  } catch {}

  let posts = [];
  let pinnedPosts = [];

  files.forEach((file) => {
    const content = fs.readFileSync(path.resolve(__dirname, "data", "users", req.params.user, "posts", file)).toString();
    const stats = fs.statSync(path.resolve(__dirname, "data", "users", req.params.user, "posts", file));

    converter.makeHtml(content);

    let opts = converter.getMetadata();

    let post = {
      user: req.params.user,
      title: opts.title || file.split(".")[0],
      description: opts.description,
      url: file.split(".")[0],
      mtime: stats.mtime,
      btime: stats.birthtime,
      mtime_formatted: dateFormatter(stats.mtime),
    };

    if (opts.pinned != undefined) pinnedPosts.push(post);
    else posts.push(post);
  });

  posts.sort((a, b) => b.btime - a.btime);
  pinnedPosts.sort((a, b) => b.btime - a.btime);

  res.render("user", { user: req.params.user, posts: posts, pinned_posts: pinnedPosts, about: converter.makeHtml(about) });
});

APP.get("/:user/:post_id", (req, res) => {
  if ((!/^[A-Za-z0-9]+$/.test(req.params.user), !/^[A-Za-z0-9-]+$/.test(req.params.post_id))) {
    res.status(404).render("error", { type: "user not found" });
    return;
  }

  let content = "";
  let modifyDate;

  try {
    content = fs.readFileSync(path.resolve(__dirname, "data", "users", req.params.user, "posts", req.params.post_id + ".md")).toString();
    modifyDate = fs.statSync(path.resolve(__dirname, "data", "users", req.params.user, "posts", req.params.post_id + ".md")).mtime;
  } catch {
    res.status(404).render("error", { type: "post not found" });
    return;
  }

  StatMan.incrementPost(req.params.user, req.params.post_id);
  StatMan.incrementUser(req.params.user);
  StatMan.incrementGlobalVisits();

  let convertedData = converter.makeHtml(content);

  let opts = converter.getMetadata();

  res.render("post", { user: req.params.user, title: opts.title || req.params.post_id, modify_date: dateFormatter(modifyDate), data: convertedData });
});

APP.get("/:user/files/:file_name", (req, res) => {
  // Disallow image access from different source :P
  if ((req.headers["sec-fetch-site"] == "none" || req.headers["sec-fetch-dest"] != "image") && BLOCKED_IMAGE_TYPES_FROM_REMOTE.some((type) => req.params.file_name.endsWith(type))) {
    res.status(404).render("error", { type: "file not accessible" });
    return;
  }

  if ((!/^[A-Za-z0-9]+$/.test(req.params.user), !/^[A-Za-z0-9-]+$/.test(req.params.post_id), /^[A-Za-z0-9-]+$/.test(req.params.file_name))) {
    res.status(404).render("error", { type: "user" });
    return;
  }

  let filePath = path.resolve(__dirname, "data", "users", req.params.user, "files", req.params.file_name);

  if (!fs.existsSync(filePath)) {
    res.status(404).render("error", { type: "file not found" });
    return;
  }

  res.sendFile(filePath);
});

APP.listen(PORT, () => {
  // Create data folder if it does not exist already
  if (!fs.existsSync(path.resolve(__dirname, "data", "users"))) {
    fs.mkdirSync(path.resolve(__dirname, "data", "users"), { recursive: true });
  }

  log(`\n%a[%lSYS%a] Statman using iterval: %d${STATMAN_INTERVAL}ms`);
  log(`%a[%lSYS%a] Blocked image file extensions: %d${BLOCKED_IMAGE_TYPES_FROM_REMOTE.join("%a, %d")}`);
  log(`%a[%lSYS%a] Blogs listening on port: %d${PORT}\n`);

  parentPort.postMessage("SERVER_STARTED");
});