/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you 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.apache.omid;
  
  import org.apache.phoenix.thirdparty.com.google.common.base.Preconditions;
  import org.apache.phoenix.thirdparty.com.google.common.io.Resources;
  import org.apache.commons.beanutils.BeanUtils;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import org.yaml.snakeyaml.Yaml;
  
  import java.io.IOException;
  import java.lang.reflect.InvocationTargetException;
  import java.nio.charset.Charset;
  import java.util.HashMap;
  import java.util.Map;
  
  @SuppressWarnings("WeakerAccess")
  public class YAMLUtils {
  
      private static final Logger LOG = LoggerFactory.getLogger(YAMLUtils.class);
  
      public void loadSettings(String resourcePath, String defaultResourcePath, Object bean) {
          try {
              Map properties = loadSettings(resourcePath, defaultResourcePath);
              BeanUtils.populate(bean, properties);
          } catch (IllegalAccessException | InvocationTargetException | IOException e) {
              throw new IllegalStateException(e);
          }
      }
  
      public void loadSettings(String resourcePath, Object bean) {
          try {
              Map properties = loadSettings(null, resourcePath);
              BeanUtils.populate(bean, properties);
          } catch (IllegalAccessException | InvocationTargetException | IOException e) {
              throw new IllegalStateException(e);
          }
      }
  
      @SuppressWarnings("unchecked")
      public Map loadSettings(String resourcePath, String defaultResourcePath) throws IOException {
          Map defaultSetting = loadAsMap(defaultResourcePath);
          Preconditions.checkState(defaultSetting.size() > 0, String.format("Failed to load file '%s' from classpath", defaultResourcePath));
          if (resourcePath != null) {
              Map userSetting = loadAsMap(resourcePath);
              defaultSetting.putAll(userSetting);
          }
          return defaultSetting;
      }
  
      @SuppressWarnings("unchecked")
      public Map loadAsMap(String path) throws IOException {
          try {
              String content = Resources.toString(Resources.getResource(path), Charset.forName("UTF-8"));
              LOG.debug("Loaded resource file '{}'\n{}", path, content);
              return loadStringAsMap(content);
          } catch (IllegalArgumentException e) {
              return new HashMap();
          }
      }
  
      @SuppressWarnings("unchecked")
      public Map loadStringAsMap(String content) {
          try {
              Map settings = new Yaml().loadAs(content, Map.class);
              return (settings != null) ? settings : new HashMap(0);
          } catch (IllegalArgumentException e) {
              return new HashMap();
          }
      }
  
  }