/*
    * 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.dict;
  
  import java.io.File;
  import java.io.IOException;
  import java.io.InputStream;
  import java.text.SimpleDateFormat;
  import java.util.ArrayList;
  import java.util.Date;
  import java.util.List;
  import java.util.Map;
  
  import javax.annotation.PostConstruct;
  
  import org.codelibs.core.io.FileUtil;
  import org.codelibs.elasticsearch.runner.net.Curl;
  import org.codelibs.elasticsearch.runner.net.CurlResponse;
  import org.codelibs.fess.Constants;
  import org.codelibs.fess.util.ComponentUtil;
  import org.codelibs.fess.util.ResourceUtil;
  import org.dbflute.optional.OptionalEntity;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  public class DictionaryManager {
      private static final Logger logger = LoggerFactory.getLogger(DictionaryManager.class);
  
      protected List<DictionaryCreator> creatorList = new ArrayList<>();
  
      @PostConstruct
      public void init() {
          creatorList.forEach(creator -> {
              creator.setDictionaryManager(this);
          });
      }
  
      public DictionaryFile<? extends DictionaryItem>[] getDictionaryFiles() {
          try (CurlResponse response =
                  Curl.get(ResourceUtil.getElasticsearchHttpUrl() + "/_configsync/file").header("Content-Type", "application/json")
                          .param("fields", "path,@timestamp").param("size", ComponentUtil.getFessConfig().getPageDictionaryMaxFetchSize())
                          .execute()) {
              final Map<String, Object> contentMap = response.getContentAsMap();
              @SuppressWarnings("unchecked")
              final List<Map<String, Object>> fileList = (List<Map<String, Object>>) contentMap.get("file");
              return fileList
                      .stream()
                      .map(fileMap -> {
                          try {
                              final String path = fileMap.get("path").toString();
                              final Date timestamp =
                                      new SimpleDateFormat(Constants.DATE_FORMAT_ISO_8601_EXTEND_UTC).parse(fileMap.get("@timestamp")
                                              .toString());
                              for (final DictionaryCreator creator : creatorList) {
                                  final DictionaryFile<? extends DictionaryItem> file = creator.create(path, timestamp);
                                  if (file != null) {
                                      return file;
                                  }
                              }
                          } catch (final Exception e) {
                              logger.warn("Failed to load " + fileMap, e);
                          }
                          return null;
                      }).filter(file -> file != null).toArray(n -> new DictionaryFile<?>[n]);
          } catch (final IOException e) {
              throw new DictionaryException("Failed to access dictionaries", e);
          }
      }
  
      public OptionalEntity<DictionaryFile<? extends DictionaryItem>> getDictionaryFile(final String id) {
          for (final DictionaryFile<? extends DictionaryItem> dictFile : getDictionaryFiles()) {
              if (dictFile.getId().equals(id)) {
                  return OptionalEntity.of(dictFile);
              }
          }
          return OptionalEntity.empty();
      }
  
      public void store(final DictionaryFile<? extends DictionaryItem> dictFile, final File file) {
          getDictionaryFile(dictFile.getId()).ifPresent(currentFile -> {
              if (currentFile.getTimestamp().getTime() > dictFile.getTimestamp().getTime()) {
                  throw new DictionaryException(dictFile.getPath() + " was updated.");
              }
  
              // TODO use stream
                  try (CurlResponse response =
                         Curl.post(ResourceUtil.getElasticsearchHttpUrl() + "/_configsync/file").header("Content-Type", "application/json")
                                 .param("path", dictFile.getPath()).body(FileUtil.readUTF8(file)).execute()) {
                     final Map<String, Object> contentMap = response.getContentAsMap();
                     if (!Constants.TRUE.equalsIgnoreCase(contentMap.get("acknowledged").toString())) {
                         throw new DictionaryException("Failed to update " + dictFile.getPath());
                     }
                 } catch (final IOException e) {
                     throw new DictionaryException("Failed to update " + dictFile.getPath(), e);
                 }
 
             }).orElse(() -> {
             throw new DictionaryException(dictFile.getPath() + " does not exist.");
         });
     }
 
     public InputStream getContentInputStream(final DictionaryFile<? extends DictionaryItem> dictFile) {
         try {
             return Curl.get(ResourceUtil.getElasticsearchHttpUrl() + "/_configsync/file").header("Content-Type", "application/json")
                     .param("path", dictFile.getPath()).execute().getContentAsStream();
         } catch (final IOException e) {
             throw new DictionaryException("Failed to access " + dictFile.getPath(), e);
         }
     }
 
     public void addCreator(final DictionaryCreator creator) {
         creatorList.add(creator);
     }
 
 }