/*
    *    Copyright 2012-2022 the original author or authors.
    *
    *    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
    *
    *       https://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.mybatis.caches.memcached;
  
  import java.io.IOException;
  import java.io.InputStream;
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Properties;
  
  /**
   * Converter from the Config to a proper {@link MemcachedConfiguration}.
   *
   * @author Simone Tripodi
   */
  final class MemcachedConfigurationBuilder {
  
    /**
     * This class instance.
     */
    private static final MemcachedConfigurationBuilder INSTANCE = new MemcachedConfigurationBuilder();
  
    private static final String SYSTEM_PROPERTY_MEMCACHED_PROPERTIES_FILENAME = "memcached.properties.filename";
  
    /**
     *
     */
    private static final String MEMCACHED_RESOURCE = "memcached.properties";
  
    private final String memcachedPropertiesFilename;
  
    /**
     * The setters used to extract properties.
     */
    private final List<AbstractPropertySetter<?>> settersRegistry = new ArrayList<AbstractPropertySetter<?>>();
  
    /**
     * Hidden constructor, this class can't be instantiated.
     */
    private MemcachedConfigurationBuilder() {
      memcachedPropertiesFilename = System.getProperty(SYSTEM_PROPERTY_MEMCACHED_PROPERTIES_FILENAME, MEMCACHED_RESOURCE);
  
      settersRegistry.add(new StringPropertySetter("org.mybatis.caches.memcached.keyprefix", "keyPrefix", "_mybatis_"));
      settersRegistry.add(new StringPropertySetter("org.mybatis.caches.memcached.username", "username", ""));
      settersRegistry.add(new StringPropertySetter("org.mybatis.caches.memcached.password", "password", ""));
  
      settersRegistry
          .add(new IntegerPropertySetter("org.mybatis.caches.memcached.expiration", "expiration", 60 * 60 * 24 * 30));
      settersRegistry.add(new IntegerPropertySetter("org.mybatis.caches.memcached.timeout", "timeout", 5));
      settersRegistry.add(new TimeUnitSetter());
  
      settersRegistry.add(new BooleanPropertySetter("org.mybatis.caches.memcached.asyncget", "usingAsyncGet", false));
      settersRegistry
          .add(new BooleanPropertySetter("org.mybatis.caches.memcached.compression", "compressionEnabled", false));
      settersRegistry.add(new BooleanPropertySetter("org.mybatis.caches.memcached.sasl", "usingSASL", false));
  
      settersRegistry.add(new InetSocketAddressListPropertySetter());
      settersRegistry.add(new ConnectionFactorySetter());
    }
  
    /**
     * Return this class instance.
     *
     * @return this class instance.
     */
    public static MemcachedConfigurationBuilder getInstance() {
      return INSTANCE;
    }
  
    /**
     * Parses the Config and builds a new {@link MemcachedConfiguration}.
     *
     * @return the converted {@link MemcachedConfiguration}.
     */
    public MemcachedConfiguration parseConfiguration() {
      return parseConfiguration(getClass().getClassLoader());
    }
  
    /**
     * Parses the Config and builds a new {@link MemcachedConfiguration}.
     *
     * @param the
     *          {@link ClassLoader} used to load the {@code memcached.properties} file in classpath.
     *
     * @return the converted {@link MemcachedConfiguration}.
     */
   public MemcachedConfiguration parseConfiguration(ClassLoader classLoader) {
     Properties config = new Properties();
 
     // load the properties specified from /memcached.properties, if present
     InputStream input = classLoader.getResourceAsStream(memcachedPropertiesFilename);
     if (input != null) {
       try {
         config.load(input);
       } catch (IOException e) {
         throw new RuntimeException("An error occurred while reading classpath property '" + memcachedPropertiesFilename
             + "', see nested exceptions", e);
       } finally {
         try {
           input.close();
         } catch (IOException e) {
           // close quietly
         }
       }
     }
 
     MemcachedConfiguration memcachedConfiguration = new MemcachedConfiguration();
 
     for (AbstractPropertySetter<?> setter : settersRegistry) {
       setter.set(config, memcachedConfiguration);
     }
 
     return memcachedConfiguration;
   }
 
 }