/*
    * Copyright 2012-2025 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.job;
  
  import java.util.Map;
  import java.util.Set;
  import java.util.stream.Collectors;
  
  import org.apache.logging.log4j.LogManager;
  import org.apache.logging.log4j.Logger;
  import org.codelibs.core.lang.StringUtil;
  import org.codelibs.fess.helper.LabelTypeHelper;
  import org.codelibs.fess.helper.LanguageHelper;
  import org.codelibs.fess.mylasta.direction.FessConfig;
  import org.codelibs.fess.opensearch.client.SearchEngineClient;
  import org.codelibs.fess.util.ComponentUtil;
  import org.codelibs.fess.util.DocumentUtil;
  import org.opensearch.index.query.QueryBuilder;
  import org.opensearch.script.Script;
  
  /**
   * Job class for updating label information in the search index.
   * This job processes documents and updates their label fields based on URL pattern matching.
   */
  public class UpdateLabelJob {
  
      private static final Logger logger = LogManager.getLogger(UpdateLabelJob.class);
  
      /**
       * Query builder for filtering documents to be processed.
       */
      protected QueryBuilder queryBuilder = null;
  
      /**
       * Default constructor for UpdateLabelJob.
       */
      public UpdateLabelJob() {
          super();
      }
  
      /**
       * Executes the label update job.
       * Processes documents in the search index and updates their label fields.
       *
       * @return execution result message
       */
      public String execute() {
          final SearchEngineClient searchEngineClient = ComponentUtil.getSearchEngineClient();
          final FessConfig fessConfig = ComponentUtil.getFessConfig();
          final LabelTypeHelper labelTypeHelper = ComponentUtil.getLabelTypeHelper();
          final LanguageHelper languageHelper = ComponentUtil.getLanguageHelper();
  
          final StringBuilder resultBuf = new StringBuilder();
  
          try {
              final long count = searchEngineClient.updateByQuery(fessConfig.getIndexDocumentUpdateIndex(), option -> {
                  if (queryBuilder != null) {
                      option.setQuery(queryBuilder);
                  }
                  return option.setFetchSource(new String[] { fessConfig.getIndexFieldUrl(), fessConfig.getIndexFieldLang() }, null);
              }, (builder, hit) -> {
                  try {
                      final Map<String, Object> doc = hit.getSourceAsMap();
                      final String url = DocumentUtil.getValue(doc, fessConfig.getIndexFieldUrl(), String.class);
                      if (StringUtil.isNotBlank(url)) {
                          final Set<String> labelSet = labelTypeHelper.getMatchedLabelValueSet(url);
                          final Script script = languageHelper.createScript(doc, "ctx._source." + fessConfig.getIndexFieldLabel()
                                  + "=new String[]{" + labelSet.stream().map(s -> "\"" + s + "\"").collect(Collectors.joining(",")) + "}");
                          return builder.setScript(script);
                      }
                  } catch (final Exception e) {
                      logger.warn("Failed to process search hit: {}", hit, e);
                  }
                  return null;
              });
              resultBuf.append(count).append(" documents").append("\n");
          } catch (final Exception e) {
              logger.error("Could not update labels.", e);
              resultBuf.append(e.getMessage()).append("\n");
          }
  
          return resultBuf.toString();
      }
  
      /**
       * Sets the query builder for filtering documents.
      *
      * @param queryBuilder the query builder to filter documents
      * @return this UpdateLabelJob instance for method chaining
      */
     public UpdateLabelJob query(final QueryBuilder queryBuilder) {
         this.queryBuilder = queryBuilder;
         return this;
     }
 }