import { ServiceImpl } from '@connectrpc/connect'
import { keyBy } from '@atproto/common'
import { Service } from '../../../proto/bsky_connect.js'
import { Database } from '../db/index.js'
import { TimeCidKeyset, paginate } from '../db/pagination.js'
import { countAll } from '../db/util.js'

export default (db: Database): Partial<ServiceImpl<typeof Service>> => ({
  async getActorLists(req) {
    const { actorDid, cursor, limit } = req
    const { ref } = db.db.dynamic
    let builder = db.db
      .selectFrom('list')
      .where('creator', '=', actorDid)
      .selectAll()
    const keyset = new TimeCidKeyset(ref('list.sortAt'), ref('list.cid'))
    builder = paginate(builder, {
      limit,
      cursor,
      keyset,
      tryIndex: true,
    })
    const lists = await builder.execute()
    return {
      listUris: lists.map((item) => item.uri),
      cursor: keyset.packFromResult(lists),
    }
  },

  async getListMembers(req) {
    const { listUri, cursor, limit } = req
    const { ref } = db.db.dynamic
    let builder = db.db
      .selectFrom('list_item')
      .where('listUri', '=', listUri)
      .selectAll()

    const keyset = new TimeCidKeyset(
      ref('list_item.sortAt'),
      ref('list_item.cid'),
    )

    builder = paginate(builder, {
      limit,
      cursor,
      keyset,
      tryIndex: true,
    })

    const listItems = await builder.execute()
    return {
      listitems: listItems.map((item) => ({
        uri: item.uri,
        did: item.subjectDid,
      })),
      cursor: keyset.packFromResult(listItems),
    }
  },

  async getListMembership(req) {
    const { actorDid, listUris } = req
    if (listUris.length === 0) {
      return { listitemUris: [] }
    }
    const res = await db.db
      .selectFrom('list_item')
      .where('subjectDid', '=', actorDid)
      .where('listUri', 'in', listUris)
      .selectAll()
      .execute()
    const byListUri = keyBy(res, 'listUri')
    const listitemUris = listUris.map((uri) => byListUri.get(uri)?.uri ?? '')
    return {
      listitemUris,
    }
  },

  async getListCount(req) {
    const res = await db.db
      .selectFrom('list_item')
      .select(countAll.as('count'))
      .where('list_item.listUri', '=', req.listUri)
      .executeTakeFirst()
    return {
      count: res?.count,
    }
  },
})