import { Products, Recommendation, TrendingProduct } from './Contracts';

class Trending {
  /**
   * The recommendation response from Dynamic Yield.
   *
   * @type {Recommendation}
   */
  private recommendation: Recommendation;

  /**
   * The player Products collection.
   *
   * @type {Products}
   */
  private ___products___: Products;

  /**
   * Create a new Trending instance.
   *
   * @param  {Recommendation} recommendation
   * @param  {Products} products
   * @return {Trending}
   */
  constructor(recommendation: Recommendation, products: Products) {
    this.recommendation = recommendation;
    this.___products___ = products;
  }

  /**
   * Returns the trending headline text.
   *
   * @return {string}
   */
  public get header(): string {
    return this.recommendation.textMap.header;
  }

  /**
   * Returns the trending sub-headline text.
   *
   * @return {string}
   */
  public get subHeader(): string {
    return this.recommendation.textMap.subHeader;
  }

  /**
   * Returns the trending products disclaimers.
   *
   * @return {string}
   */
  public get disclaimers(): string {
    const disclaimers = this.recommendation.products.reduce((disclaimers, trending) => {      
      const product = this.___products___[trending.code];

      return { ...disclaimers, ...product.meta.disclaimer };
    }, {});

    return Object.values(disclaimers).join(' ');
  }

  /**
   * Returns the trending products models.
   *
   * @return {Array<TrendingProduct>}
   */
  public get products(): Array<TrendingProduct> {
    return this.recommendation.products.reduce((products, { code }) => {
      const { title, assets, meta } = this.___products___[code];
      
      return [...products, { asset: assets[0], title, type: meta.type }];
    }, <Array<TrendingProduct>>[]);
  }

  /**
   * Serialize the Trending data model.
   *
   * @param  {string} [key]
   * @return {object}
   */
  public toJSON(key?: string) {
    const { header, subHeader, disclaimers, products } = this;

    return { header, subHeader, disclaimers, products };
  }
}

export default Trending;