import { parseRssItems } from '../rss-helpers.js'
import { state } from '../state.js'
import { requireAdminAuth } from '../auth.js'
import { queueNuggetsTagsWrite } from '../data.js'

let cache = null // { url, episodes }
let cacheAt = 0
const CACHE_TTL = 30 * 60 * 1000

function feedUrl() {
  return state.cachedSiteContent?.nuggets?.rssFeedUrl?.trim() ?? ''
}

export async function fetchNuggetsEpisodes() {
  const url = feedUrl()
  if (!url) { cache = null; return [] }

  const now = Date.now()
  if (cache && cache.url === url && (now - cacheAt) < CACHE_TTL) {
    return cache.episodes
  }

  const controller = new AbortController()
  const timeout = setTimeout(() => controller.abort(), 8000)
  try {
    const response = await fetch(url, { signal: controller.signal })
    clearTimeout(timeout)
    if (!response.ok) throw new Error(`RSS fetch failed: ${response.status}`)
    const xml = await response.text()
    const episodes = parseRssItems(xml)
    cache = { url, episodes }
    cacheAt = now
    return episodes
  } catch (err) {
    clearTimeout(timeout)
    // Serve stale cache for this same URL rather than a hard failure, if we have one.
    if (cache && cache.url === url) return cache.episodes
    throw err
  }
}

function withTags(episodes) {
  return episodes.map(ep => ({ ...ep, tags: state.nuggetsEpisodeTags[ep.audioUrl] ?? [] }))
}

function cleanTags(input) {
  const list = Array.isArray(input) ? input : []
  const seen = new Set()
  const out = []
  for (const t of list) {
    const tag = String(t ?? '').trim().replace(/\s+/g, ' ').slice(0, 40)
    const key = tag.toLowerCase()
    if (tag && !seen.has(key)) { seen.add(key); out.push(tag) }
  }
  return out.slice(0, 12)
}

export function register(app) {
  app.get('/api/admin/nuggets/episode-tags', requireAdminAuth, async (_req, res) => {
    try {
      const episodes = await fetchNuggetsEpisodes()
      res.json({ episodes: withTags(episodes).map(({ title, pubDate, audioUrl, episode, tags }) => ({ title, pubDate, audioUrl, episode, tags })) })
    } catch (err) {
      res.status(502).json({ message: 'Could not load episodes from the feed.' })
    }
  })

  app.put('/api/admin/nuggets/episode-tags', requireAdminAuth, (req, res) => {
    const audioUrl = String(req.body?.audioUrl ?? '')
    if (!audioUrl) { res.status(400).json({ message: 'audioUrl is required.' }); return }
    const tags = cleanTags(req.body?.tags)
    if (tags.length) state.nuggetsEpisodeTags[audioUrl] = tags
    else delete state.nuggetsEpisodeTags[audioUrl]
    queueNuggetsTagsWrite()
    res.json({ ok: true, tags })
  })

  app.get('/api/nuggets/episodes', async (_req, res) => {
    const configured = Boolean(feedUrl())
    try {
      const episodes = await fetchNuggetsEpisodes()
      res.json({ episodes: withTags(episodes.slice(0, 6)), configured })
    } catch (err) {
      console.error('[nuggets/episodes] RSS fetch error:', err.message)
      res.json({ episodes: [], configured })
    }
  })

  app.get('/api/nuggets/episodes/all', async (_req, res) => {
    const configured = Boolean(feedUrl())
    try {
      const episodes = await fetchNuggetsEpisodes()
      res.json({ episodes: withTags(episodes), configured })
    } catch (err) {
      console.error('[nuggets/episodes/all] RSS fetch error:', err.message)
      res.json({ episodes: [], configured })
    }
  })
}