Class Search

adev/shared-docs/services/search.service.ts:44–231

@Service()
export class Search {
  readonly searchQuery = signal('');

  private readonly config = inject(ENVIRONMENT);
  private readonly client = inject(ALGOLIA_CLIENT);

  debounceParams = debounced(this.searchQuery, SEARCH_DELAY);

  readonly resultsResource = resource({
    params: () => this.debounceParams.value() || undefined, // coerces empty string to undefined
    loader: async ({params}) => this.searchWithQuery(params),
  });

  readonly searchResults = linkedSignal<SearchResultItem[] | undefined, SearchResultItem[]>({
    source: this.resultsResource.value,
    computation: (next, prev) => (!next && this.searchQuery() ? prev?.value : next) ?? [],
  });

  readonly emptyState = linkedSignal<{query: string; pending: boolean}, 'start' | 'no-results'>({
    source: () => ({
      query: this.searchQuery(),
      pending:
        this.searchQuery() !== this.debounceParams.value() || this.resultsResource.isLoading(),
    }),
    computation: ({query, pending}, prev) => {
      if (!query) {
        return 'start';
      }
      return pending ? (prev?.value ?? 'start') : 'no-results';
    },
  });

  private getUniqueSearchResultItems(items: SearchResult[]): SearchResult[] {
    const uniqueUrls = new Set<string>();

    return items.filter((item) => {
      if (item.type === 'content' && !item._snippetResult.content) {
        return false;
      }
      // Ensure that this result actually matched on the type.
      // If not, this is going to be a duplicate. There should be another result in
      // the list that already matched on its type.
      // A lvl2 match will also return all its lvl3 results as well, even if those
      // values don't also match the query.
      if (
        item.type.indexOf('lvl') === 0 &&
        item._snippetResult.hierarchy?.[item.type as 'lvl1']?.matchLevel === 'none'
      ) {
        return false;
      }

      if (item['url'] && typeof item['url'] === 'string' && !uniqueUrls.has(item['url'])) {
        uniqueUrls.add(item['url']);
        return true;
      }
      return false;
    });
  }