SearchFactory.java

package nl.knaw.huygens.alexandria.endpoint.search;

/*
 * #%L
 * alexandria-main
 * =======
 * Copyright (C) 2015 - 2017 Huygens ING (KNAW)
 * =======
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public
 * License along with this program.  If not, see
 * <http://www.gnu.org/licenses/gpl-3.0.html>.
 * #L%
 */

import static java.util.stream.Collectors.toList;

import java.net.URI;
import java.util.List;
import java.util.Map;
import java.util.concurrent.atomic.AtomicInteger;

import javax.inject.Inject;
import javax.inject.Singleton;

import nl.knaw.huygens.alexandria.api.model.search.SearchInfo;
import nl.knaw.huygens.alexandria.api.model.search.SearchResultPage;

@Singleton
public class SearchFactory {

  @Inject
  public SearchFactory() {
  }

  public SearchResultPage createSearchResultPage(final String baseURI, final int pageNumber, final SearchResult searchResult, final List<Map<String, Object>> results) {
    final int pageSize = searchResult.getPageSize();
    final int lastPageNumber = Math.max(1, searchResult.getTotalPages());

    final SearchInfo searchInfo = new SearchInfo()//
        .setId(searchResult.getId())//
        .setQuery(searchResult.getQuery())//
        .setSearchDurationInMs(searchResult.getSearchDurationInMs())//
        .setTotalPages(searchResult.getTotalPages())//
        .setPageSize(pageSize)//
        .setTotalResults(searchResult.getTotalResults());

    final AtomicInteger counter = new AtomicInteger(pageSize * (pageNumber - 1));
    final List<Map<String, Object>> records = results.stream().map(r -> {
      r.put("_resultNumber", counter.incrementAndGet());
      return r;
    }).collect(toList());

    final SearchResultPage searchResultPage = new SearchResultPage()//
        .setPageNumber(pageNumber)//
        .setSearchInfo(searchInfo)//
        .setRecords(records)//
        .setFirstPageURI(URI.create(baseURI + 1))//
        .setLastPageURI(URI.create(baseURI + (lastPageNumber)));

    if (pageNumber > 1) {
      searchResultPage.setPreviousPageURI(URI.create(baseURI + (pageNumber - 1)));
    }

    final boolean isLast = pageNumber == lastPageNumber;
    if (!isLast) {
      searchResultPage.setNextPageURI(URI.create(baseURI + (pageNumber + 1)));
    }

    return searchResultPage;
  }

}