/**
 * @flow
 * FieldValue representation wrapper
 */
import AnyJs from './utils/any';
import { buildNativeArray } from './utils/serialize';

// TODO: Salakar: Refactor in v6
export default class FieldValue {
  _type: string;

  _elements: AnyJs[] | any;

  constructor(type: string, elements?: AnyJs[]) {
    this._type = type;
    this._elements = elements;
  }

  get type(): string {
    return this._type;
  }

  get elements(): AnyJs[] {
    return this._elements;
  }

  static delete(): FieldValue {
    return new FieldValue(TypeFieldValueDelete);
  }

  static serverTimestamp(): FieldValue {
    return new FieldValue(TypeFieldValueTimestamp);
  }

  static arrayUnion(...elements: AnyJs[]) {
    // TODO Salakar: v6: validate elements, any primitive or FirestoreReference allowed
    // TODO Salakar: v6: explicitly deny use of serverTimestamp - only allowed on set/update
    // TODO Salakar: v6: explicitly deny use of nested arrays - not supported on sdk
    return new FieldValue(TypeFieldValueUnion, buildNativeArray(elements));
  }

  static arrayRemove(...elements: AnyJs[]) {
    // TODO Salakar: v6: validate elements, any primitive or FirestoreReference allowed
    // TODO Salakar: v6: explicitly deny use of serverTimestamp - only allowed on set/update
    // TODO Salakar: v6: explicitly deny use of nested arrays - not supported on sdk
    return new FieldValue(TypeFieldValueRemove, buildNativeArray(elements));
  }
}

export const TypeFieldValueDelete = 'delete';
export const TypeFieldValueRemove = 'remove';
export const TypeFieldValueUnion = 'union';
export const TypeFieldValueTimestamp = 'timestamp';