Facets.java

    public PatientPlatformSearchResult<StudyModel> findStudies(SearchFilter filter, ResourceResolver resourceResolver) {

        Map<String, String> predicateGroupMap = new HashMap<>();
        predicateGroupMap.put("type", "cq:PageContent");
        predicateGroupMap.put("path", filter.getHomePagePath());
        predicateGroupMap.put("property", "sling:resourceType");
        predicateGroupMap.put("property.value", ResourceType.CLINICAL_TRIAL.getResourceType());
        if (filter.getResultsonly()) {
            predicateGroupMap.put(TAG_ID_PREDICATE, WITH_RESULTS_TAG_ID);
        }

        if (CollectionUtils.isNotEmpty(filter.getStatus())) {
            for (int i = 0; i < filter.getStatus().size(); i++) {
                predicateGroupMap.put("11_tagid." + (i + 1) + "_value", STATUS_TAG_ID + "/" + filter.getStatus().get(i));
            }
        }
        // If there is not status selected, filter only by valid statuses
        else if (CollectionUtils.isNotEmpty(filter.getAllStatus())) {
            for (int i = 0; i < filter.getAllStatus().size(); i++) {
                predicateGroupMap.put("22_tagid." + (i + 1) + "_value", STATUS_TAG_ID + "/" + filter.getAllStatus().get(i));
            }
        }

        predicateGroupMap.put("group.p.or", "true");
        String title = filter.getTitle();
        if (StringUtils.isNotEmpty(title)) {
            predicateGroupMap.put("group.1_group.p.or", "true");
            predicateGroupMap.put("group.1_group.1_fulltext", title + "~");
            predicateGroupMap.put("group.1_group.1_fulltext.relPath", "'jcr:title'");
            predicateGroupMap.put("group.1_group.2_fulltext", title + "~");
            predicateGroupMap.put("group.1_group.2_fulltext.relPath", "'expertTitle'");
        }

        String id = filter.getId();
        if (StringUtils.isNotEmpty(id)) {
            predicateGroupMap.put("group.1_group.p.or", "true");
            predicateGroupMap.put("group.1_group.3_property", "nctId");
            predicateGroupMap.put("group.1_group.3_property.value", id);
            predicateGroupMap.put("group.1_group.4_property", "orgId");
            predicateGroupMap.put("group.1_group.4_property.value", id);
            predicateGroupMap.put("group.1_group.5_property", "secondaryId");
            predicateGroupMap.put("group.1_group.5_property.value", id);
        }

        if (StringUtils.isNotEmpty(filter.getTitle()) && StringUtils.isEmpty(filter.getMedicalCondition())) {
            // Limit the search to the medical conditions tags
            predicateGroupMap.put("group.1_group.tagsearch", filter.getTitle());
            predicateGroupMap.put("group.1_group.tagsearch.lang", filter.getLocale());
        } else if (StringUtils.isNotEmpty(filter.getMedicalCondition())) {
            predicateGroupMap.put("33_tagid.1_value", MEDICAL_CONDITIONS_TAG_ID + "/" + filter.getMedicalCondition());
        }

        if (StringUtils.isNotEmpty(filter.getCountry()) || StringUtils.isNotEmpty(filter.getCity()) ||
                StringUtils.isNotEmpty(filter.getZip())) {
            StringBuilder locationName = new StringBuilder();

            locationName.append("\"").append(LOCATIONS_TAG_ID).append("\"").append(" ");

            locationName.append("\"");
            if (StringUtils.isNotEmpty(filter.getCountry())) {
                locationName.append(filter.getCountry());
                locationName.append("/");
            }

            if (StringUtils.isNotEmpty(filter.getCity())) {
                locationName.append(filter.getCity());
                locationName.append("/");
            }

            if (StringUtils.isNotEmpty(filter.getCity())) {
                locationName.append(filter.getZip());
            }
            locationName.append("\"");

            predicateGroupMap.put("1_fulltext", locationName.toString());
            predicateGroupMap.put("1_fulltext.relPath", "'cq:tags'");
        }

        predicateGroupMap.put("80_orderby", "@statusRanking");
        predicateGroupMap.put("81_orderby", "@patientRanking");
        predicateGroupMap.put("82_orderby", "@jcr:score");
        
        predicateGroupMap.put("p.facets", "true");

        return getResults(predicateGroupMap, resourceResolver, filter, StudyModel.class);
    }

    private <T> PatientPlatformSearchResult<T> getResults(Map<String, String> predicateMap, ResourceResolver resourceResolver, SearchFilter filter, @Nonnull Class<T> classOfT) {
        Query query = queryBuilder.createQuery(PredicateGroup.create(predicateMap), resourceResolver.adaptTo(Session.class));

        long limit = DEFAULT_RESULT_SIZE_LIMIT;
        if (filter != null && filter.getLimit() != null) {
            limit = filter.getLimit();
        }

        long offset = DEFAULT_RESULT_OFFSET;
        if (filter != null && filter.getOffset() != null) {
            offset = filter.getOffset();
        }
        query.setStart(offset);
        query.setHitsPerPage(limit);

        final SearchResult result = query.getResult();
        List<T> results = new ArrayList<>();
        for (Hit hit : result.getHits()) {
            try {
                results.add(hit.getResource().adaptTo(classOfT));
            } catch (RepositoryException e) {
                logger.error("Error in retrieving result element", e);
            }
        }

        // Add facets to the result
        PatientPlatformSearchResult<T> ppResults = new PatientPlatformSearchResult<>();
        try {
            Map<String, Facet> facets = result.getFacets();
            facets.keySet().forEach(key -> {
                Facet cqFacet = facets.get(key);

                if (StringUtils.contains(key, TAG_ID_PREDICATE)) {
                    cqFacet.getBuckets().forEach(bucket -> {
                        // Process locations
                        if (StringUtils.startsWith(bucket.getValue(), LOCATIONS_TAG_ID)) {
                            ppResults.addFacetEntry(FacetNames.LOCATIONS, bucket.getValue(), bucket.getCount());
                        }
                        // Process with-results items
                        else if (StringUtils.startsWith(bucket.getValue(), WITH_RESULTS_TAG_ID)) {
                            ppResults.addFacetEntry(FacetNames.HAS_RESULTS, bucket.getValue(), bucket.getCount());
                        }
                    });
                }
            });

        } catch (RepositoryException e) {
            logger.warn("Could not obtain facets");
        }

        ppResults.addResults(results);
        ppResults.setCount(result.getTotalMatches());

        return ppResults;
    }