// @flow
import type {
  QueryCondition,
  EqCondition,
} from './query-condition.js.flow'
import type { SortNotation } from './sort-notation.js.flow'
import type { DocumentPath } from './document-path.js.flow'

export type SetOperator = { [field: DocumentPath]: any }
export type IncOperator = { [field: DocumentPath]: number }
export type MinOperator = { [field: DocumentPath]: any }
export type MaxOperator = { [field: DocumentPath]: any }
export type MulOperator = { [field: DocumentPath]: number }
export type AddToSetOperator = { [field: DocumentPath]: any | { $each: Array<any> } }
export type RegularAddToSetOperator = { [field: DocumentPath]: { $each: Array<any> } }
export type PopOperator = { [field: DocumentPath]: 1 | - 1 }
export type UnsetOperator = { [field: DocumentPath]: '' }

export type PullOperator = { +[field: DocumentPath]: QueryCondition | EqCondition }
export type RegularPullOperator = { +[field: DocumentPath]: QueryCondition }

export type PushModifier = {
  $each: Array<any>,
  $slice?: number,
  $sort?: SortNotation,
  $position?: number,
}
export type PushOperator = { [field: DocumentPath]: any | PushModifier }
export type RegularPushOperator = { [field: DocumentPath]: PushModifier }

type TypeSpecification = true | { $type: 'timestamp' | 'date' }
export type CurrentDateOperator = { [field: DocumentPath]: TypeSpecification }
export type BitOperator = {
  [field: DocumentPath]: {
    and?: number,
    or?: number,
    xor?: number,
  }
}

/**
 * RenameOperator
 * a bit different operator from MongoDB's $rename operator
 * https://docs.mongodb.com/manual/reference/operator/update/rename/
 *
 * The values are not 'DotNotationString's but field names.
 * The following sample object in mongodb
 * { $rename: { "name.first": "name.fname" } }
 *
 * will be the following object in power-assign.
 *
 * { $rename: { "name.first": "fname" } }
 *
 * See that the value doesn't contain "name".
 * When this operator is passed to MongoDB via phenyl-mongodb,
 * new field names will be automatically corrected to fit the MongoDB's spec.
 */
export type RenameOperator = {
  [field: DocumentPath]: string
}

/**
 * New operator which construct instances of the given path
 * Notice:
 *
 * Once RestoreOperator is JSON.stringify-ed, the fields with Class<Restorable> will be removed.
 * To avoid this, you can choose two alternatives.
 *
 * 1) Implement static method toJSON() to Classes
 *   class Foo {
 *     static toJSON() { return '' }
 *   }
 *
 * 2) Use updateOperationToJSON() function exported from oad-utils
 *    import { updateOperationToJSON } from 'oad-utils/jsnext'
 *    const operation: UpdateOperation = { $restore: { foo: Foo } }
 *    JSON.stringify(updateOperationToJSON(operation)) // {"$restore":{"foo":""}}
 */
export type RestoreOperator = {
  [field: DocumentPath]: '' | Class<*>
}

export type RegularUpdateOperation = $Shape<{
  $set: SetOperator,
  $inc: IncOperator,
  $min: MinOperator,
  $max: MaxOperator,
  $mul: MulOperator,
  $addToSet: RegularAddToSetOperator,
  $pop: PopOperator,
  $pull: RegularPullOperator,
  $push: RegularPushOperator,
  $currentDate: CurrentDateOperator,
  $bit: BitOperator,
  $unset: UnsetOperator,
  $restore: RestoreOperator,
  $rename: RenameOperator,
}>

export type UpdateOperation = $Shape<{
  $set: SetOperator,
  $inc: IncOperator,
  $min: MinOperator,
  $max: MaxOperator,
  $mul: MulOperator,
  $addToSet: AddToSetOperator,
  $pop: PopOperator,
  $pull: RegularPullOperator,
  $push: PushOperator,
  $currentDate: CurrentDateOperator,
  $bit: BitOperator,
  $unset: UnsetOperator,
  $restore: RestoreOperator,
  $rename: RenameOperator,
}>

export type UpdateOperatorName =
  '$set' |
  '$inc' |
  '$min' |
  '$max' |
  '$mul' |
  '$addToSet' |
  '$pop' |
  '$pull' |
  '$push' |
  '$currentDate' |
  '$bit' |
  '$unset' |
  '$restore' |
  '$rename'

export type UpdateOperator =
  SetOperator |
  IncOperator |
  MinOperator |
  MaxOperator |
  MulOperator |
  AddToSetOperator |
  PopOperator |
  PullOperator |
  PushOperator |
  CurrentDateOperator |
  BitOperator |
  UnsetOperator |
  RenameOperator |
  RestoreOperator |
  RenameOperator