/**

  * Copyright (C) 2010 Daniel Manzke <daniel.manzke@googlemail.com>

  *

  * 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.apache.onami.autobind.integrations.commons.configuration;

 import java.io.File;

 import java.lang.annotation.Annotation;

 import java.net.MalformedURLException;

 import java.net.URL;

 import java.util.Map;

 import java.util.logging.Level;

 import java.util.logging.Logger;

 import javax.inject.Named;

 import javax.inject.Singleton;

 import org.apache.commons.configuration.ConfigurationException;

 import org.apache.commons.configuration.FileConfiguration;

 import org.apache.onami.autobind.configuration.Configuration;

 import org.apache.onami.autobind.install.BindingStage;

 import org.apache.onami.autobind.scanner.features.BindingScannerFeature;

 /**

  * This Class will be called for each Class, which is annotated with

  * {@link Configuration} and which needs an Apache Commons-based Configuration.

  * 

  * @author Daniel Manzke

  * 

  */

 @Singleton

 public class CommonsConfigurationFeature extends BindingScannerFeature {

         private Logger _logger = Logger.getLogger(CommonsConfigurationFeature.class.getName());

         @Override

         public BindingStage accept(Class<Object> annotatedClass, Map<String, Annotation> annotations) {

                 if (annotations.containsKey(Configuration.class.getName())) {

                         Configuration config = (Configuration) annotations.get(Configuration.class.getName());

                         if (FileConfiguration.class.isAssignableFrom(config.to())) {

                                 return BindingStage.BOOT_BEFORE;

                         }

                 }

                 return BindingStage.IGNORE;

         }

         @SuppressWarnings("unchecked")

         @Override

         public void process(Class<Object> annotatedClass, Map<String, Annotation> annotations) {

                 Configuration config = (Configuration) annotations.get(Configuration.class.getName());

                 Named name = config.name();

                 // TODO Implement Location overriding

                 URL url;

                 switch (config.location().type()) {

                 case FILE:

                         File file = new File(config.location().value());

                         if (!file.exists()) {

                                 _logger.log(Level.WARNING, "Ignoring Configuration " + name + " in "

                                                 + config.location() + ". In the Path " + file.getAbsolutePath()

                                                 + " no Configuration was found.");

                                 return;

                         }

                         try {

                                 url = file.toURI().toURL();

                         } catch (MalformedURLException e) {

                                 _logger.log(Level.WARNING, "Ignoring Configuration " + name + " in "

                                                 + config.location() + ". It has an illegal URL-Format.", e);

                                 return;

                         }

                         break;

                 case URL:

                         try {

                                 url = new URL(config.location().value());

                         } catch (MalformedURLException e) {

                                 _logger.log(Level.WARNING, "Ignoring Configuration " + name + " in "

                                                 + config.location() + ". It has an illegal URL-Format.", e);

                                 return;

                         }

                         break;

                 case CLASSPATH:

                 default:

                         url = this.getClass().getResource(config.location().value());

                         break;

                 }

                 if (url == null) {

                         _logger.log(Level.WARNING, "Ignoring Configuration " + name + " in "

                                         + config.location() + ", because is couldn't be found in the Classpath.");

                         // TODO Throw an exception if config doesn't exist?

                         return;

                 }

                 Named named = null;

                 if (name.value().length() > 0) {

                         named = name;

                 }

                 FileConfiguration configuration;

                 try {

                         // Class<? extends FileConfiguration> interf =

                         // config.to().asSubclass(FileConfiguration.class);

                         Class<FileConfiguration> interf = (Class<FileConfiguration>) config.to();

                         configuration = (FileConfiguration) injector.getInstance(interf);

                         configuration.load(url);

                         bindInstance(configuration, interf, named, null);

                         bindInstance(configuration, FileConfiguration.class, named, null);

                         bindInstance(configuration, org.apache.commons.configuration.Configuration.class,

                                 named, null);

                 } catch (ConfigurationException e) {

                         _logger.log(Level.WARNING, "Configuration " + name + " couldn't be loaded/bound: "

                                         + e.getMessage(), e);

                 }

         }

 }