import slugify from '@sindresorhus/slugify'

export default async function (doc, rootLevel, context) {
  const { next, line, match, tail, level, head } = doc

  const headingLevel = +tail().split(' ')[0]
  const text = tail().split(' ').slice(1).join(' ')
  const slug = slugify(text)

  const node = {
    type: head(),
    level: headingLevel,
    text,
    slug,
    class: '',
    href: '',
    children: []
  }

  while (await next(rootLevel)) {
    if (match('class')) node.class = tail()
    if (match('href')) node.href = tail()
  }

  context.page.headings.push(node)

  return node
}