reversible state converter

converter.coffee

module.exports =
  converter: (targetObjs, beforeObj, afterObj, isCheckBefore, isReverse, callback)->
    if isReverse
      if isCheckBefore
        conditions = _.merge {}, afterObj
      updates = _.merge {}, beforeObj
    else
      if isCheckBefore
        conditions = _.merge {}, beforeObj
      updates = _.merge {}, afterObj

    conditions[$isolated] = true
    conditions._id =
      $in: _.map targetObjs, '_id'

    Documnt.update conditions, updates,
      $multi: true
    , callback