const path = require("path");

// String -> String

// @url examples:
// - https://registry.yarnpkg.com/acorn-es7-plugin/-/acorn-es7-plugin-1.1.7.tgz
// - https://registry.npmjs.org/acorn-es7-plugin/-/acorn-es7-plugin-1.1.7.tgz
// - git+https://github.com/srghma/node-shell-quote.git
// - git+https://1234user:1234pass@git.graphile.com/git/users/1234user/postgraphile-supporter.git
// - https://codeload.github.com/Gargron/emoji-mart/tar.gz/934f314fd8322276765066e8a2a6be5bac61b1cf

function urlToName(url) {
  // Yarn generates `codeload.github.com` tarball URLs, where the final
  // path component (file name) is the git hash. See #111.
  // See also https://github.com/yarnpkg/yarn/blob/989a7406/src/resolvers/exotics/github-resolver.js#L24-L26
  let isCodeloadGitTarballUrl =
    url.startsWith("https://codeload.github.com/") && url.includes("/tar.gz/");

  if (url.startsWith("git+") || isCodeloadGitTarballUrl) {
    return path.basename(url);
  }

  return url
    .replace(/https:\/\/(.)*(.com)\//g, "") // prevents having long directory names
    .replace(/[@/%:-]/g, "_"); // replace @ and : and - and % characters with underscore
}

module.exports = urlToName;