const fetch = require("node-fetch");

async function github(url) {
  const regex = /(?:https|git)(?::\/\/|@)github\.com[\/:]([^\/:]+)\/(.+)/i;
  const match = url.match(regex);

  if (!match) throw new Error("Invalid GitHub URL");

  const user = match[1];
  const repo = match[2].replace(/\.git$/, "");
  const apiUrl = `https://api.github.com/repos/${user}/${repo}/zipball`;

  const head = await fetch(apiUrl, { method: "HEAD" });
  if (!head.ok) throw new Error("Failed to fetch repository");

  let disposition = head.headers.get("content-disposition");
  let filename = "repository.zip";

  if (disposition) {
    const m = disposition.match(/attachment; filename=(.*)/);
    if (m && m[1]) filename = m[1];
  }

  return {
    user,
    repo,
    url: apiUrl,
    filename: filename
  };
}

module.exports = { github };