/*

  * The baseCode project

  *

  * Copyright (c) 2013 University of British Columbia

  *

  * 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 ubic.basecode.util;

 import java.io.File;

 import java.io.IOException;

 import java.net.URISyntaxException;

 import java.net.URL;

 import org.apache.commons.configuration2.PropertiesConfiguration;

 import org.apache.commons.configuration2.builder.FileBasedBuilderParametersImpl;

 import org.apache.commons.configuration2.builder.FileBasedConfigurationBuilder;

 import org.apache.commons.configuration2.convert.DefaultListDelimiterHandler;

 import org.apache.commons.configuration2.convert.ListDelimiterHandler;

 import org.apache.commons.configuration2.ex.ConfigurationException;

 import org.apache.commons.configuration2.io.FileHandler;

 import org.apache.commons.configuration2.io.FileLocator;

 import org.apache.commons.configuration2.io.FileLocatorUtils;

 import org.apache.commons.io.FileUtils;

 /**

  * Convenience methods for loading configurations

  *

  * @author Paul

  *

  */

 public class ConfigUtils {

     private static final ListDelimiterHandler LIST_DELIMITER_HANDLER = new DefaultListDelimiterHandler( ',' );

     /**

      * @param file

      * @return

      */

     public static FileBasedConfigurationBuilder<PropertiesConfiguration> getConfigBuilder( File file )

             throws ConfigurationException {

         if ( !file.exists() ) {

             try {

                 FileTools.touch( file );

             } catch ( IOException e ) {

                 throw new ConfigurationException( "Couldn't create the file: " + e.getMessage() );

             }

         }

         FileBasedConfigurationBuilder<PropertiesConfiguration> builder = new FileBasedConfigurationBuilder<PropertiesConfiguration>(

                 PropertiesConfiguration.class );

         builder.configure( new FileBasedBuilderParametersImpl().setFile( file ).setListDelimiterHandler( LIST_DELIMITER_HANDLER ) );

         return builder;

     }

     /**

      * @param name If the file does not exist, attempts to create it in the user's home directory.

      * @return

      */

     public static FileBasedConfigurationBuilder<PropertiesConfiguration> getConfigBuilder( String name )

             throws ConfigurationException {

         File f = locateConfig( name );

         return getConfigBuilder( f );

     }

     /**

      * @param url

      * @return

      * @throws ConfigurationException

      */

     public static FileBasedConfigurationBuilder<PropertiesConfiguration> getConfigBuilder( URL url )

             throws ConfigurationException {

         File file;

         try {

             file = new File( url.toURI() );

             return getConfigBuilder( file );

         } catch ( URISyntaxException e ) {

             throw new ConfigurationException( "Couldn't map url to a uri: " + url );

         }

     }

     /**

      * @param name the classpath location, such as "project.properties" in the base package, or

      *        org/foo/project.properties.

      * @return

      * @throws ConfigurationException

      */

     public static PropertiesConfiguration loadClasspathConfig( String name ) throws ConfigurationException {

         ClassLoader loader = Thread.currentThread().getContextClassLoader();

         URL url = loader.getResource( name );

         if ( url == null ) {

             throw new ConfigurationException( "Couldn't locate: " + name );

         }

         PropertiesConfiguration pc = createConfiguration();

         FileHandler handler = new FileHandler( pc );

         handler.setURL( url );

         handler.load();

         return pc;

     }

     /**

      * @param file

      * @return

      * @throws ConfigurationException

      */

     public static PropertiesConfiguration loadConfig( File file ) throws ConfigurationException {

         if ( !file.exists() ) {

             try {

                 FileTools.touch( file );

             } catch ( IOException e ) {

                 throw new ConfigurationException( "Couldn't create the file: " + e.getMessage() );

             }

         }

         PropertiesConfiguration pc = createConfiguration();

         FileHandler handler = new FileHandler( pc );

         handler.setFile( file );

         handler.load();

         return pc;

     }

     /**

      * @param name If the file does not exist, attempts to create it in the user's home directory.

      * @return

      * @throws ConfigurationException

      */

     public static PropertiesConfiguration loadConfig( String name ) throws ConfigurationException {

         /*

          * We have to locate it, if it's not a path.

          */

         File f = locateConfig( name );

         if ( f == null ) {

             /*

              * Try again from the classpath?

              */

             return loadClasspathConfig( name );

         }

         return loadConfig( f );

     }

     /**

      * @param url

      * @return

      * @throws ConfigurationException

      */

     public static PropertiesConfiguration loadConfig( URL url ) throws ConfigurationException {

         try {

             File file = new File( url.toURI() );

             return loadConfig( file );

         } catch ( Exception e ) {

             throw new ConfigurationException( "Couldn't map url to a uri: " + url );

         }

     }

     /**

      * @param name

      * @return

      * @throws ConfigurationException

      */

     private static File locateConfig( String name ) throws ConfigurationException {

         File f;

         FileLocator fl = FileLocatorUtils.fileLocator().fileName( name ).create();

         URL location = FileLocatorUtils.locate( fl );

         if ( location == null ) {

             f = new File( name );

             if ( f.isAbsolute() ) {

                 return f;

             }

             return new File( FileUtils.getUserDirectory(), name );

         }

         try {

             return new File( location.toURI() );

         } catch ( Exception e ) {

             throw new ConfigurationException( "Couldn't map url to a uri: " + name );

         }

     }

     public static URL locate( String name ) {

         FileLocator fl = FileLocatorUtils.fileLocator().fileName( name ).create();

         return FileLocatorUtils.locate( fl );

     }

     private static PropertiesConfiguration createConfiguration() {

         PropertiesConfiguration pc = new PropertiesConfiguration();

         pc.setListDelimiterHandler( LIST_DELIMITER_HANDLER );

         return pc;

     }

 }