import * as Bull from 'bull'
import { logger } from '../../../helpers/logger'
import { REMOTE_SCHEME, WEBSERVER } from '../../../initializers/constants'
import { sendFollow } from '../../activitypub/send'
import { sanitizeHost } from '../../../helpers/core-utils'
import { loadActorUrlOrGetFromWebfinger } from '../../../helpers/webfinger'
import { getOrCreateActorAndServerAndModel } from '../../activitypub/actor'
import { retryTransactionWrapper } from '../../../helpers/database-utils'
import { ActorFollowModel } from '../../../models/activitypub/actor-follow'
import { ActorModel } from '../../../models/activitypub/actor'
import { Notifier } from '../../notifier'
import { sequelizeTypescript } from '../../../initializers/database'

export type ActivitypubFollowPayload = {
  followerActorId: number
  name: string
  host: string
}

async function processActivityPubFollow (job: Bull.Job) {
  const payload = job.data as ActivitypubFollowPayload
  const host = payload.host

  logger.info('Processing ActivityPub follow in job %d.', job.id)

  let targetActor: ActorModel
  if (!host || host === WEBSERVER.HOST) {
    targetActor = await ActorModel.loadLocalByName(payload.name)
  } else {
    const sanitizedHost = sanitizeHost(host, REMOTE_SCHEME.HTTP)
    const actorUrl = await loadActorUrlOrGetFromWebfinger(payload.name + '@' + sanitizedHost)
    targetActor = await getOrCreateActorAndServerAndModel(actorUrl)
  }

  const fromActor = await ActorModel.load(payload.followerActorId)

  return retryTransactionWrapper(follow, fromActor, targetActor)
}
// ---------------------------------------------------------------------------

export {
  processActivityPubFollow
}

// ---------------------------------------------------------------------------

async function follow (fromActor: ActorModel, targetActor: ActorModel) {
  if (fromActor.id === targetActor.id) {
    throw new Error('Follower is the same than target actor.')
  }

  // Same server, direct accept
  const state = !fromActor.serverId && !targetActor.serverId ? 'accepted' : 'pending'

  const actorFollow = await sequelizeTypescript.transaction(async t => {
    const [ actorFollow ] = await ActorFollowModel.findOrCreate({
      where: {
        actorId: fromActor.id,
        targetActorId: targetActor.id
      },
      defaults: {
        state,
        actorId: fromActor.id,
        targetActorId: targetActor.id
      },
      transaction: t
    })
    actorFollow.ActorFollowing = targetActor
    actorFollow.ActorFollower = fromActor

    // Send a notification to remote server if our follow is not already accepted
    if (actorFollow.state !== 'accepted') await sendFollow(actorFollow)

    return actorFollow
  })

  if (actorFollow.state === 'accepted') Notifier.Instance.notifyOfNewUserFollow(actorFollow)
}