/*
    * 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.mylasta.direction;
  
  import java.util.concurrent.ExecutionException;
  
  import org.codelibs.fess.Constants;
  import org.dbflute.helper.jprop.ObjectiveProperties;
  import org.lastaflute.core.direction.PropertyFilter;
  
  import com.google.common.cache.Cache;
  import com.google.common.cache.CacheBuilder;
  
  public class FessConfigImpl extends FessConfig.SimpleImpl {
  
      private static final long serialVersionUID = 1L;
  
      private static class KeyNotFoundException extends Exception {
          private static final long serialVersionUID = 1L;
  
          private KeyNotFoundException(final String key) {
              super(key);
          }
      }
  
      @Override
      protected ObjectiveProperties newObjectiveProperties(final String resourcePath, final PropertyFilter propertyFilter) {
          return new ObjectiveProperties(resourcePath) { // for e.g. checking existence and filtering value
              Cache<String, String> cache = CacheBuilder.newBuilder().build();
  
              @Override
              public String get(final String propertyKey) {
                  final String plainValue = getFromCache(propertyKey);
                  final String filteredValue = propertyFilter.filter(propertyKey, plainValue);
                  verifyPropertyValue(propertyKey, filteredValue); // null checked
                  return filterPropertyAsDefault(filteredValue); // not null here
              }
  
              private String getFromCache(final String propertyKey) {
                  try {
                      return cache.get(propertyKey, () -> {
                          final String value = System.getProperty(Constants.FESS_CONFIG_PREFIX + propertyKey, super.get(propertyKey));
                          if (value == null) {
                              throw new KeyNotFoundException(propertyKey);
                          }
                          return value;
                      });
                  } catch (final ExecutionException e) {
                      if (e.getCause() instanceof KeyNotFoundException) {
                          return null;
                      }
                      return super.get(propertyKey);
                  }
              }
          };
      }
  }