import { Func, Inbox, Lifecycle, spawn, loop, STOP } from 'anneal'
import { Event as NEvent, nip19 } from 'nostr-tools'
import FlexSearch from 'flexsearch'

export type UserIndexActor = {
  addProfile: Inbox<NEvent>
  search: Func<{ query: string; limit: number }, string[]>
  lc: Lifecycle
}

export function createUserIndexActor(): UserIndexActor {
  const index = new FlexSearch.Index({ tokenize: 'forward' })

  const addProfile = new Inbox<NEvent>(0)
  const search = new Func<{ query: string; limit: number }, string[]>()
  const lc = new Lifecycle()

  spawn(lc, async () => {
    await loop(
      lc.on(() => STOP),
      addProfile.on((event) => {
        try {
          const obj = JSON.parse(event.content)
          const text = [
            obj.display_name?.trim() ?? '',
            obj.name?.trim() ?? '',
            obj.nip05
              ?.split('@')
              .map((s: string) => s.trim())
              .join(' ') ?? ''
          ].join(' ')
          if (text) {
            index.add(event.pubkey, text)
          }
        } catch {
          // skip invalid profiles
        }
      }),
      search.on(({ req: { query, limit }, reply }) => {
        const result = index.search(query, { limit })
        reply(
          result.map((pubkey) => nip19.npubEncode(pubkey as string)).filter(Boolean) as string[]
        )
      })
    )
  })

  return { addProfile, search, lc }
}