import path from 'path'
const renderOpts = { textOnly: true, encodeEntities: true }

// This middleware exposes a list of all categories and child articles at /categories.json.
// GitHub Support uses this for internal ZenDesk search functionality.
export default async function categoriesForSupport(req, res, next) {
  const englishSiteTree = req.context.siteTree.en

  const allCategories = []

  await Promise.all(
    Object.keys(englishSiteTree).map(async (version) => {
      await Promise.all(
        englishSiteTree[version].childPages.map(async (productPage) => {
          if (productPage.page.relativePath.startsWith('early-access')) return
          if (!productPage.childPages) return

          await Promise.all(
            productPage.childPages.map(async (categoryPage) => {
              // We can't get the rendered titles from middleware/render-tree-titles
              // here because that middleware only runs on the current version, and this
              // middleware processes all versions.
              const name = categoryPage.page.title.includes('{')
                ? await categoryPage.page.renderProp('title', req.context, renderOpts)
                : categoryPage.page.title

              allCategories.push({
                name,
                published_articles: await findArticlesPerCategory(categoryPage, [], req.context),
              })
            })
          )
        })
      )
    })
  )

  return res.json(allCategories)
}

async function findArticlesPerCategory(currentPage, articlesArray, context) {
  if (currentPage.page.documentType === 'article') {
    const title = currentPage.page.title.includes('{')
      ? await currentPage.page.renderProp('title', context, renderOpts)
      : currentPage.page.title

    articlesArray.push({
      title,
      slug: path.basename(currentPage.href),
    })
  }

  if (!currentPage.childPages) return articlesArray

  // Run recursively to find any articles deeper in the tree.
  await Promise.all(
    currentPage.childPages.map(async (childPage) => {
      await findArticlesPerCategory(childPage, articlesArray, context)
    })
  )

  return articlesArray
}