/*
    * Copyright 2012-2017 CodeLibs Project and the Others.
    *
    * Licensed under the Apache License, Version 2.0 (the "License");
    * you may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    *
    *     http://www.apache.org/licenses/LICENSE-2.0
    *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
   * either express or implied. See the License for the specific language
   * governing permissions and limitations under the License.
   */
  package org.codelibs.fess.util;
  
  import java.nio.charset.StandardCharsets;
  import java.util.ArrayList;
  import java.util.HashMap;
  import java.util.LinkedHashMap;
  import java.util.List;
  import java.util.Map;
  
  import org.codelibs.fess.Constants;
  import org.elasticsearch.search.aggregations.Aggregations;
  import org.elasticsearch.search.aggregations.bucket.filter.Filter;
  import org.elasticsearch.search.aggregations.bucket.terms.Terms;
  
  import com.google.common.io.BaseEncoding;
  
  public class FacetResponse {
      protected Map<String, Long> queryCountMap = new LinkedHashMap<>();
  
      protected List<Field> fieldList = new ArrayList<>();
  
      public FacetResponse(final Aggregations aggregations) {
          aggregations
                  .forEach(aggregation -> {
                      if (aggregation.getName().startsWith(Constants.FACET_FIELD_PREFIX)) {
                          final Terms termFacet = (Terms) aggregation;
                          fieldList.add(new Field(termFacet));
                      } else if (aggregation.getName().startsWith(Constants.FACET_QUERY_PREFIX)) {
                          final Filter queryFacet = (Filter) aggregation;
                          final String encodedQuery = queryFacet.getName().substring(Constants.FACET_QUERY_PREFIX.length());
                          queryCountMap.put(new String(BaseEncoding.base64().decode(encodedQuery), StandardCharsets.UTF_8),
                                  queryFacet.getDocCount());
                      }
  
                  });
      }
  
      public boolean hasFacetResponse() {
          return queryCountMap != null || fieldList != null;
      }
  
      public static class Field {
          protected Map<String, Long> valueCountMap = new HashMap<>();
  
          protected String name;
  
          public Field(final Terms termFacet) {
              final String encodedField = termFacet.getName().substring(Constants.FACET_FIELD_PREFIX.length());
              name = new String(BaseEncoding.base64().decode(encodedField), StandardCharsets.UTF_8);
              for (final Terms.Bucket tfEntry : termFacet.getBuckets()) {
                  valueCountMap.put(tfEntry.getKeyAsString(), tfEntry.getDocCount());
              }
          }
  
          /**
           * @return the valueCountMap
           */
          public Map<String, Long> getValueCountMap() {
              return valueCountMap;
          }
  
          /**
           * @return the name
           */
          public String getName() {
              return name;
          }
  
      }
  
      /**
       * @return the queryCountMap
       */
      public Map<String, Long> getQueryCountMap() {
          return queryCountMap;
      }
  
      /**
       * @return the fieldList
       */
      public List<Field> getFieldList() {
          return fieldList;
      }
  
 }