import { formatReleases, renderPatchNotes } from '../../lib/release-notes-utils.js'
import { all } from '../../lib/enterprise-server-releases.js'

export default async function ghesReleaseNotesContext(req, res, next) {
  if (!(req.pagePath.endsWith('/release-notes') || req.pagePath.endsWith('/admin'))) return next()
  const [requestedPlan, requestedRelease] = req.context.currentVersion.split('@')
  if (requestedPlan !== 'enterprise-server') return next()

  const ghesReleaseNotes = req.context.site.data['release-notes']['enterprise-server']

  // If the requested GHES release isn't found in data/release-notes/enterprise-server/*,
  // and it IS a valid GHES release, try being helpful and redirecting to the old location.
  // Otherwise, 404.
  if (!Object.keys(ghesReleaseNotes).includes(requestedRelease.replace(/\./, '-'))) {
    return all.includes(requestedRelease)
      ? res.redirect(`https://enterprise.github.com/releases/${requestedRelease}.0/notes`)
      : next()
  }

  // Returns [{version, patches: [{version, patchVersion, intro, date, sections: { features: [], bugs: []...}} ]}]
  req.context.ghesReleases = formatReleases(ghesReleaseNotes)

  // Find the notes for the current release only
  const currentReleaseNotes = req.context.ghesReleases.find(
    (r) => r.version === requestedRelease
  ).patches

  // Run the current release notes through the markdown rendering pipeline.
  // Returns the current release's patches array: [{version, patchVersion, intro, date, sections}]
  req.context.ghesReleaseNotes = await renderPatchNotes(currentReleaseNotes, req.context)

  // GHES release notes on docs started with 2.20 but older release notes exist on enterprise.github.com.
  // So we want to use _all_ GHES versions when calculating next and previous releases.
  req.context.latestPatch = req.context.ghesReleaseNotes[0].version
  req.context.latestRelease = all[0]

  // Add convenience props for "Supported releases" section on GHES Admin landing page (NOT release notes).
  req.context.ghesReleases.forEach((release) => {
    release.firstPreviousRelease = all[all.findIndex((v) => v === release.version) + 1]
    release.secondPreviousRelease =
      all[all.findIndex((v) => v === release.firstPreviousRelease) + 1]
  })

  return next()
}