Rebuild: the catalog API and Newznab, from voyager 1

- /api (Newznab: caps, search, tvsearch, movie, music, book, get) for
  Prowlarr, Sonarr and Radarr: voyager 1's controller and XML on the new
  catalog; readable releases not known to miss files; NEWZNAB_API_KEY.
- /api/v1/releases (q, cat, readable, complete, source, poster, size,
  sort, paging), /api/v1/releases/:id with its files (decoded from the
  chunks; NzbService.files, shared with the NZB), /api/v1/stats
  (estimates, plus history and tail progress), /health. Open, as voyager
  1's catalog; the web interface uses it.
- release_category(name): voyager 1's categorizer without the archive
  contents, a generated column with a (category, posted_at) index.
- @adonisjs/static for the web interface (next).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

app/controllers/newznab_controller.ts

@@ -0,0 +1,115 @@
+import type { HttpContext } from '@adonisjs/core/http'
+import env from '#start/env'
+import NzbService from '#services/nzb_service'
+import SearchService from '#services/search_service'
+import { capsXml, errorXml, expandCategories, resultsXml, type NewznabServer } from '#lib/newznab/index'
+
+const LIMITS = { max: 100, default: 50 }
+
+/** Search functions and the category each defaults to when `cat` is absent. */
+const SEARCH_FUNCTIONS: Record<string, number | undefined> = {
+  'search': undefined,
+  'tvsearch': 5000,
+  'tv-search': 5000,
+  'movie': 2000,
+  'movie-search': 2000,
+  'music': 3000,
+  'audio': 3000,
+  'book': 7000,
+}
+
+/** The configured key, if any. */
+function configuredApiKey(): string | undefined {
+  const value: any = env.get('NEWZNAB_API_KEY')
+  const key = typeof value === 'string' ? value : value?.release()
+  return key || undefined
+}
+
+function int(value: unknown): number | undefined {
+  return typeof value === 'string' && /^\d+$/.test(value) ? Number(value) : undefined
+}
+
+/**
+ * Newznab API for Prowlarr, Sonarr, Radarr and the like (from voyager 1):
+ * GET /api?t=caps|search|tvsearch|movie|music|book|get&apikey=…
+ * Releases with readable names that aren't known to miss files.
+ */
+export default class NewznabController {
+  async handle({ request, response }: HttpContext) {
+    const qs = request.qs()
+    const t = String(qs.t ?? '')
+    const server = this.server(request)
+    const xml = (body: string, type = 'application/xml') => {
+      response.header('Content-Type', `${type}; charset=utf-8`)
+      return response.send(body)
+    }
+
+    const apiKey = configuredApiKey()
+    if (apiKey && qs.apikey !== apiKey) return xml(errorXml(100, 'Incorrect user credentials'))
+    if (t === 'caps') return xml(capsXml(server, LIMITS))
+
+    if (t === 'get') {
+      const id = int(qs.id)
+      if (id === undefined) return xml(errorXml(200, 'Missing parameter (id)'))
+      const nzb = await NzbService.build(id)
+      if (!nzb) return xml(errorXml(300, 'No such item'))
+      const filename = `${nzb.name.replace(/[^\w.\-()[\] ]+/g, '_').slice(0, 180) || 'release'}.nzb`
+      response.header('Content-Disposition', `attachment; filename="${filename}"`)
+      return xml(nzb.xml, 'application/x-nzb')
+    }
+
+    if (!(t in SEARCH_FUNCTIONS)) return xml(errorXml(202, `No such function (${t || 'none'})`))
+
+    const requested = String(qs.cat ?? '')
+      .split(',')
+      .map((c) => int(c.trim()))
+      .filter((c): c is number => c !== undefined)
+    const fallback = SEARCH_FUNCTIONS[t]
+    const categories = expandCategories(requested.length ? requested : fallback ? [fallback] : [])
+    const limit = Math.min(int(qs.limit) ?? LIMITS.default, LIMITS.max)
+    const offset = int(qs.offset) ?? 0
+
+    // ID-only lookups (tvdbid, imdbid, …) aren't supported: an empty result rather than everything.
+    const q = typeof qs.q === 'string' ? qs.q.trim() : ''
+    const idOnly = !q && ['tvdbid', 'tvmazeid', 'rid', 'imdbid', 'tmdbid'].some((p) => qs[p])
+    const result = idOnly
+      ? null
+      : await SearchService.search({
+          q,
+          categories,
+          readable: true,
+          notIncomplete: true,
+          maxAgeDays: int(qs.maxage),
+          season: int(qs.season),
+          episode: int(qs.season) !== undefined ? int(qs.ep) : undefined,
+          sort: 'newest',
+          perPage: limit,
+          offset,
+        })
+
+    const items = (result?.releases ?? []).map((r) => {
+      const tv = /(?:^|[._ -])S(\d{1,2})E(\d{1,3})/i.exec(r.name)
+      return {
+        id: r.id,
+        title: r.name,
+        category: r.category ?? 8010,
+        size: r.size,
+        files: r.fileCount,
+        postedAt: r.postedAt ? new Date(r.postedAt) : null,
+        poster: r.poster,
+        groups: r.groups ?? [],
+        // Passwords come with phase 2 (archive inspection).
+        password: false,
+        season: tv ? `S${tv[1].padStart(2, '0')}` : undefined,
+        episode: tv ? `E${tv[2].padStart(2, '0')}` : undefined,
+      }
+    })
+    return xml(resultsXml(server, items, offset, result?.total ?? 0), 'application/rss+xml')
+  }
+
+  private server(request: HttpContext['request']): NewznabServer {
+    const proto = request.header('x-forwarded-proto') ?? 'http'
+    const host = request.header('x-forwarded-host') ?? request.header('host') ?? 'localhost'
+    return { title: 'Voyager 2', baseUrl: `${proto}://${host}`, apiKey: configuredApiKey() }
+  }
+}