const http = require("http");
const fs = require("fs");
const path = require("path");

const PORT = 3000;
const ROOT = __dirname;

const MIME = {
  ".html": "text/html",
  ".js":   "application/javascript",
  ".json": "application/json",
  ".css":  "text/css",
  ".svg":  "image/svg+xml",
  ".png":  "image/png",
  ".ico":  "image/x-icon",
};

const server = http.createServer((req, res) => {
  let filePath = path.join(ROOT, req.url === "/" ? "index.html" : req.url);
  filePath = path.normalize(filePath);

  if (!filePath.startsWith(ROOT)) {
    res.writeHead(403);
    return res.end("Forbidden");
  }

  const ext = path.extname(filePath);
  const contentType = MIME[ext] || "application/octet-stream";

  fs.readFile(filePath, (err, data) => {
    if (err) {
      res.writeHead(404);
      return res.end("Not found");
    }
    res.writeHead(200, { "Content-Type": contentType });
    res.end(data);
  });
});

server.listen(PORT, () => {
  console.log(`Server running at http://localhost:${PORT}/`);
});