dspace-angular/src/app/core/shared/item.model.ts

import { DSpaceObject } from "./dspace-object.model";
import { Collection } from "./collection.model";
import { RemoteData } from "../data/remote-data";
import { Bitstream } from "./bitstream.model";
import { Observable } from "rxjs";
import { isNotEmpty } from "../../shared/empty.util";

export class Item extends DSpaceObject {

  /**
   * A string representing the unique handle of this Item
   */
  handle: string;

  /**
   * The Date of the last modification of this Item
   */
  lastModified: Date;

  /**
   * A boolean representing if this Item is currently archived or not
   */
  isArchived: boolean;

  /**
   * A boolean representing if this Item is currently discoverable or not
   */
  isDiscoverable: boolean;

  /**
   * A boolean representing if this Item is currently withdrawn or not
   */
  isWithdrawn: boolean;

  /**
   * An array of Collections that are direct parents of this Item
   */
  parents: RemoteData<Collection[]>;

  /**
   * The Collection that owns this Item
   */
  owningCollection: RemoteData<Collection>;

  get owner(): RemoteData<Collection> {
    return this.owningCollection;
  }

  bitstreams: RemoteData<Bitstream[]>;


  /**
   * Retrieves the thumbnail of this item
   * @returns {Observable<Bitstream>} the primaryBitstream of the "THUMBNAIL" bundle
   */
  getThumbnail(): Observable<Bitstream> {
    //TODO currently this just picks the first thumbnail
    //should be adjusted when we have a way to determine
    //the primary thumbnail from rest
    return this.getBitstreamsByBundleName("THUMBNAIL")
      .filter(thumbnails => isNotEmpty(thumbnails))
      .map(thumbnails => thumbnails[0])
  }

  /**
   * Retrieves the thumbnail for the given original of this item
   * @returns {Observable<Bitstream>} the primaryBitstream of the "THUMBNAIL" bundle
   */
  getThumbnailForOriginal(original: Bitstream): Observable<Bitstream> {
    return this.getBitstreamsByBundleName("THUMBNAIL").map(files => files
      .find(thumbnail => thumbnail
        .name.startsWith(original.name)
      )
    ).startWith(undefined);
  }

  /**
   * Retrieves all files that should be displayed on the item page of this item
   * @returns {Observable<Array<Observable<Bitstream>>>} an array of all Bitstreams in the "ORIGINAL" bundle
   */
  getFiles(): Observable<Bitstream[]> {
    return this.getBitstreamsByBundleName("ORIGINAL");
  }

  /**
   * Retrieves bitstreams by bundle name
   * @param bundleName The name of the Bundle that should be returned
   * @returns {Observable<Bitstream[]>} the bitstreams with the given bundleName
   */
  getBitstreamsByBundleName(bundleName: string): Observable<Bitstream[]> {
    return this.bitstreams.payload.startWith([])
      .map(bitstreams => bitstreams
        .filter(bitstream => bitstream.bundleName === bundleName)
      );
  }

}