import * as validator from 'validator'
import { CONSTRAINTS_FIELDS } from '../../../initializers'
import { exists } from '../misc'
import { truncate } from 'lodash'
import { isActivityPubUrlValid, isBaseActivityValid, setValidAttributedTo } from './misc'

function isActorEndpointsObjectValid (endpointObject: any) {
  return isActivityPubUrlValid(endpointObject.sharedInbox)
}

function isActorPublicKeyObjectValid (publicKeyObject: any) {
  return isActivityPubUrlValid(publicKeyObject.id) &&
    isActivityPubUrlValid(publicKeyObject.owner) &&
    isActorPublicKeyValid(publicKeyObject.publicKeyPem)
}

function isActorTypeValid (type: string) {
  return type === 'Person' || type === 'Application' || type === 'Group'
}

function isActorPublicKeyValid (publicKey: string) {
  return exists(publicKey) &&
    typeof publicKey === 'string' &&
    publicKey.startsWith('-----BEGIN PUBLIC KEY-----') &&
    publicKey.indexOf('-----END PUBLIC KEY-----') !== -1 &&
    validator.isLength(publicKey, CONSTRAINTS_FIELDS.ACTORS.PUBLIC_KEY)
}

const actorNameRegExp = new RegExp('[ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-_]+')
function isActorPreferredUsernameValid (preferredUsername: string) {
  return exists(preferredUsername) && validator.matches(preferredUsername, actorNameRegExp)
}

function isActorPrivateKeyValid (privateKey: string) {
  return exists(privateKey) &&
    typeof privateKey === 'string' &&
    privateKey.startsWith('-----BEGIN RSA PRIVATE KEY-----') &&
    // Sometimes there is a \n at the end, so just assert the string contains the end mark
    privateKey.indexOf('-----END RSA PRIVATE KEY-----') !== -1 &&
    validator.isLength(privateKey, CONSTRAINTS_FIELDS.ACTORS.PRIVATE_KEY)
}

function isActorObjectValid (actor: any) {
  return exists(actor) &&
    isActivityPubUrlValid(actor.id) &&
    isActorTypeValid(actor.type) &&
    isActivityPubUrlValid(actor.following) &&
    isActivityPubUrlValid(actor.followers) &&
    isActivityPubUrlValid(actor.inbox) &&
    isActivityPubUrlValid(actor.outbox) &&
    isActorPreferredUsernameValid(actor.preferredUsername) &&
    isActivityPubUrlValid(actor.url) &&
    isActorPublicKeyObjectValid(actor.publicKey) &&
    isActorEndpointsObjectValid(actor.endpoints) &&
    setValidAttributedTo(actor) &&

    // If this is not an account, it should be attributed to an account
    // In PeerTube we use this to attach a video channel to a specific account
    (actor.type === 'Person' || actor.attributedTo.length !== 0)
}

function isActorFollowingCountValid (value: string) {
  return exists(value) && validator.isInt('' + value, { min: 0 })
}

function isActorFollowersCountValid (value: string) {
  return exists(value) && validator.isInt('' + value, { min: 0 })
}

function isActorDeleteActivityValid (activity: any) {
  return isBaseActivityValid(activity, 'Delete')
}

function isActorFollowActivityValid (activity: any) {
  return isBaseActivityValid(activity, 'Follow') &&
    isActivityPubUrlValid(activity.object)
}

function isActorAcceptActivityValid (activity: any) {
  return isBaseActivityValid(activity, 'Accept')
}

function isActorRejectActivityValid (activity: any) {
  return isBaseActivityValid(activity, 'Reject')
}

function isActorUpdateActivityValid (activity: any) {
  normalizeActor(activity.object)

  return isBaseActivityValid(activity, 'Update') &&
    isActorObjectValid(activity.object)
}

function normalizeActor (actor: any) {
  if (!actor || !actor.url) return

  if (typeof actor.url !== 'string') {
    actor.url = actor.url.href || actor.url.url
  }

  if (actor.summary && typeof actor.summary === 'string') {
    actor.summary = truncate(actor.summary, { length: CONSTRAINTS_FIELDS.USERS.DESCRIPTION.max })

    if (actor.summary.length < CONSTRAINTS_FIELDS.USERS.DESCRIPTION.min) {
      actor.summary = null
    }
  }

  return
}

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

export {
  normalizeActor,
  isActorEndpointsObjectValid,
  isActorPublicKeyObjectValid,
  isActorTypeValid,
  isActorPublicKeyValid,
  isActorPreferredUsernameValid,
  isActorPrivateKeyValid,
  isActorObjectValid,
  isActorFollowingCountValid,
  isActorFollowersCountValid,
  isActorFollowActivityValid,
  isActorAcceptActivityValid,
  isActorRejectActivityValid,
  isActorDeleteActivityValid,
  isActorUpdateActivityValid
}
