/**
 * Fetches the latest release notes from GitHub and parses the SHA-256 checksums.
 * Returns a mapping from filename to checksum.
 */
export async function getChecksums() {
  const res = await fetch("https://api.github.com/repos/zen-browser/desktop/releases/latest", {
    headers: {
      Accept: "application/vnd.github+json",
      "X-GitHub-Api-Version": "2022-11-28",
      "User-Agent": "zen-browser-checksum-fetcher",
    },
  });
  if (!res.ok) throw new Error(`Failed to fetch GitHub release: ${res.statusText}`);
  const data = await res.json();
  const body = data.body as string;

  // Extract the checksum block
  const match = body.match(/File Checksums \(SHA-256\)[\s\S]*?```([\s\S]*?)```/);
  const checksums: Record<string, string> = {};
  if (match?.[1]) {
    for (const line of match[1].split("\n")) {
      const [hash, filename] = line.trim().split(/\s+/, 2);
      if (hash && filename) checksums[filename] = hash;
    }
  }
  return checksums;
}