const execa = require('execa');

function head(options) {
  try {
    return execa.sync('git', ['rev-parse', 'HEAD'], options).stdout;
  } catch {
    return undefined;
  }
}

function branch(options) {
  try {
    const headRef = execa.sync('git', ['rev-parse', '--abbrev-ref', 'HEAD'], options).stdout;

    if (headRef === 'HEAD') {
      const branch = execa
        .sync('git', ['show', '-s', '--pretty=%d', 'HEAD'], options)
        .stdout.replace(/^\(|\)$/g, '')
        .split(', ')
        .find((branch) => branch.startsWith('origin/'));
      return branch ? branch.match(/^origin\/(?<branch>.+)/)[1] : undefined;
    }

    return headRef;
  } catch {
    return undefined;
  }
}

module.exports = {head, branch};