const { promisify } = require('util')
const SubscriptionUpdater = require('./SubscriptionUpdater')
const SubscriptionLocator = require('./SubscriptionLocator')
const { Subscription } = require('../../models/Subscription')

function removeUserFromGroup(subscriptionId, userIdToRemove, callback) {
  SubscriptionUpdater.removeUserFromGroup(
    subscriptionId,
    userIdToRemove,
    callback
  )
}

function replaceUserReferencesInGroups(oldId, newId, callback) {
  Subscription.updateOne(
    { admin_id: oldId },
    { admin_id: newId },
    function (error) {
      if (error) {
        return callback(error)
      }

      _replaceInArray(
        Subscription,
        'manager_ids',
        oldId,
        newId,
        function (error) {
          if (error) {
            return callback(error)
          }

          _replaceInArray(Subscription, 'member_ids', oldId, newId, callback)
        }
      )
    }
  )
}

function isUserPartOfGroup(userId, subscriptionId, callback) {
  SubscriptionLocator.getSubscriptionByMemberIdAndId(
    userId,
    subscriptionId,
    function (err, subscription) {
      const partOfGroup = !!subscription
      callback(err, partOfGroup)
    }
  )
}

function getTotalConfirmedUsersInGroup(subscriptionId, callback) {
  SubscriptionLocator.getSubscription(subscriptionId, (err, subscription) =>
    callback(err, subscription?.member_ids?.length)
  )
}

function _replaceInArray(model, property, oldValue, newValue, callback) {
  // Mongo won't let us pull and addToSet in the same query, so do it in
  // two. Note we need to add first, since the query is based on the old user.
  const query = {}
  query[property] = oldValue

  const setNewValue = {}
  setNewValue[property] = newValue

  const setOldValue = {}
  setOldValue[property] = oldValue

  model.updateMany(query, { $addToSet: setNewValue }, function (error) {
    if (error) {
      return callback(error)
    }
    model.updateMany(query, { $pull: setOldValue }, callback)
  })
}

module.exports = {
  removeUserFromGroup,
  replaceUserReferencesInGroups,
  getTotalConfirmedUsersInGroup,
  isUserPartOfGroup,
  promises: {
    removeUserFromGroup: promisify(removeUserFromGroup),
    replaceUserReferencesInGroups: promisify(replaceUserReferencesInGroups),
    getTotalConfirmedUsersInGroup: promisify(getTotalConfirmedUsersInGroup),
    isUserPartOfGroup: promisify(isUserPartOfGroup),
  },
}