/*
    * Copyright 2012-2021 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.score;
  
  import java.util.Arrays;
  import java.util.Map;
  import java.util.function.Function;
  
  import org.apache.logging.log4j.LogManager;
  import org.apache.logging.log4j.Logger;
  import org.codelibs.core.lang.StringUtil;
  import org.codelibs.fesen.action.bulk.BulkRequestBuilder;
  import org.codelibs.fesen.action.bulk.BulkResponse;
  import org.codelibs.fesen.action.search.SearchResponse;
  import org.codelibs.fesen.action.update.UpdateRequestBuilder;
  import org.codelibs.fesen.index.query.QueryBuilders;
  import org.codelibs.fesen.script.Script;
  import org.codelibs.fesen.script.ScriptType;
  import org.codelibs.fesen.search.SearchHit;
  import org.codelibs.fess.es.client.SearchEngineClient;
  import org.codelibs.fess.mylasta.direction.FessConfig;
  import org.codelibs.fess.util.ComponentUtil;
  
  public abstract class ScoreBooster {
      private static final Logger logger = LogManager.getLogger(ScoreBooster.class);
  
      protected BulkRequestBuilder bulkRequestBuilder = null;
  
      protected int priority = 1;
  
      protected String requestTimeout = "1m";
  
      protected int requestCacheSize = 1000;
  
      protected String scriptLang = "painless";
  
      protected String scriptCode = null;
  
      protected Function<Map<String, Object>, String[]> idFinder = params -> {
          final FessConfig fessConfig = ComponentUtil.getFessConfig();
          final SearchEngineClient client = ComponentUtil.getSearchEngineClient();
          final String index = fessConfig.getIndexDocumentUpdateIndex();
          final Object url = params.get("url");
          if (url == null) {
              return StringUtil.EMPTY_STRINGS;
          }
          final SearchResponse response = client.prepareSearch(index).setQuery(QueryBuilders.termQuery(fessConfig.getIndexFieldUrl(), url))
                  .setFetchSource(false).setSize(fessConfig.getPageScoreBoosterMaxFetchSizeAsInteger()).execute().actionGet(requestTimeout);
          return Arrays.stream(response.getHits().getHits()).map(SearchHit::getId).toArray(n -> new String[n]);
      };
  
      protected Function<Map<String, Object>, Long> requestHandler = params -> {
          final FessConfig fessConfig = ComponentUtil.getFessConfig();
          final String[] ids = idFinder.apply(params);
          if (ids.length == 0) {
              return 0L;
          }
          final SearchEngineClient client = ComponentUtil.getSearchEngineClient();
          if (bulkRequestBuilder == null) {
              bulkRequestBuilder = client.prepareBulk();
          }
          final String index = fessConfig.getIndexDocumentUpdateIndex();
          for (final String id : ids) {
              bulkRequestBuilder.add(client.prepareUpdate().setIndex(index).setId(id)
                      .setScript(new Script(ScriptType.INLINE, scriptLang, scriptCode, params)));
          }
          if (bulkRequestBuilder.numberOfActions() > requestCacheSize) {
              flush();
          }
          return (long) ids.length;
      };
  
      public abstract long process();
  
      protected void enable() {
          final ScoreUpdater scoreUpdater = ComponentUtil.getComponent("scoreUpdater");
          scoreUpdater.addScoreBooster(this);
      }
  
      protected long updateScore(final Map<String, Object> params) {
          return requestHandler.apply(params);
      }
  
      protected UpdateRequestBuilder createUpdateRequestBuilder() {
          final FessConfig fessConfig = ComponentUtil.getFessConfig();
          return ComponentUtil.getSearchEngineClient().prepareUpdate().setIndex(fessConfig.getIndexDocumentSearchIndex());
     }
 
     protected void flush() {
         if (bulkRequestBuilder != null) {
             final BulkResponse response = bulkRequestBuilder.execute().actionGet(requestTimeout);
             if (response.hasFailures()) {
                 logger.warn("Failed to update scores: {}", response.buildFailureMessage());
             }
             bulkRequestBuilder = null;
         }
     }
 
     public int getPriority() {
         return this.priority;
     }
 
     public void setPriority(final int priority) {
         this.priority = priority;
     }
 
     public void setRequestTimeout(final String bulkRequestTimeout) {
         this.requestTimeout = bulkRequestTimeout;
     }
 
     public void setRequestCacheSize(final int requestCacheSize) {
         this.requestCacheSize = requestCacheSize;
     }
 
     public void setScriptLang(final String scriptLang) {
         this.scriptLang = scriptLang;
     }
 
     public void setScriptCode(final String scriptCode) {
         this.scriptCode = scriptCode;
     }
 }