import Component from '@ember/component';
import { get, set, getProperties } from '@ember/object';
import ComputedProperty from '@ember/object/computed';
import { inject } from '@ember/service';
import { task, TaskInstance } from 'ember-concurrency';
import { action } from 'ember-decorators/object';
import Notifications from 'wherehows-web/services/notifications';
import { NotificationEvent } from 'wherehows-web/services/notifications';
import { IOwner } from 'wherehows-web/typings/api/datasets/owners';
import {
  OwnerType,
  readDatasetOwnersByUrn,
  readDatasetOwnerTypesWithoutConsumer,
  updateDatasetOwnersByUrn
} from 'wherehows-web/utils/api/datasets/owners';

export default class DatasetOwnershipContainer extends Component {
  /**
   * The urn identifier for the dataset
   * @type {string}
   */
  urn: string;

  /**
   * List of owners for the dataset
   * @type {Array<IOwner>}
   */
  owners: Array<IOwner>;

  /**
   * List of types available for a dataset owner
   * @type {Array<OwnerType>}
   */
  ownerTypes: Array<OwnerType>;

  /**
   * Reference to the application notifications Service
   * @type {ComputedProperty<Notifications>}
   */
  notifications: ComputedProperty<Notifications> = inject();

  didInsertElement() {
    get(this, 'getContainerDataTask').perform();
  }

  didUpdateAttrs() {
    get(this, 'getContainerDataTask').perform();
  }

  /**
   * An async parent task to group all data tasks for this container component
   * @type {Task<TaskInstance<Promise<any>>, (a?: any) => TaskInstance<TaskInstance<Promise<any>>>>}
   */
  getContainerDataTask = task(function*(this: DatasetOwnershipContainer): IterableIterator<TaskInstance<Promise<any>>> {
    const tasks = Object.values(getProperties(this, ['getDatasetOwnersTask', 'getDatasetOwnerTypesTask']));

    yield* tasks.map(task => task.perform());
  });

  /**
   * Reads the owners for this dataset
   * @type {Task<Promise<Array<IOwner>>, (a?: any) => TaskInstance<Promise<Array<IOwner>>>>}
   */
  getDatasetOwnersTask = task(function*(this: DatasetOwnershipContainer): IterableIterator<Promise<Array<IOwner>>> {
    const owners = yield readDatasetOwnersByUrn(get(this, 'urn'));

    set(this, 'owners', owners);
  });

  /**
   * Reads the owner types available
   * @type {Task<Promise<Array<OwnerType>>, (a?: any) => TaskInstance<Promise<Array<OwnerType>>>>}
   */
  getDatasetOwnerTypesTask = task(function*(
    this: DatasetOwnershipContainer
  ): IterableIterator<Promise<Array<OwnerType>>> {
    const ownerTypes = yield readDatasetOwnerTypesWithoutConsumer();
    set(this, 'ownerTypes', ownerTypes);
  });

  /**
   * Handles user notifications when save succeeds or fails
   * @template T the return type for the save request
   * @param {Promise<T>} request to update owners
   * @returns {Promise<T>}
   * @memberof DatasetOwnershipContainer
   */
  async notifyOnSave<T>(this: DatasetOwnershipContainer, request: Promise<T>): Promise<T> {
    const { notify } = get(this, 'notifications');

    try {
      await request;
      notify(NotificationEvent.success, { content: 'Changes have been successfully saved!' });
    } catch (e) {
      notify(NotificationEvent.error, { content: 'An error occurred while saving.' });
    }

    return request;
  }

  /**
   * Persists the changes to the owners list
   * @param {Array<IOwner>} updatedOwners
   * @return {Promise<{}>}
   */
  @action
  async saveOwnerChanges(this: DatasetOwnershipContainer, updatedOwners: Array<IOwner>): Promise<{}> {
    const result = await this.notifyOnSave(updateDatasetOwnersByUrn(get(this, 'urn'), '', updatedOwners));
    const { notify } = get(this, 'notifications');

    try {
      get(this, 'getDatasetOwnersTask').perform();
    } catch (e) {
      notify(NotificationEvent.error, { content: 'Error occurred getting updated owners.' });
    }
    return result;
  }
}