/*

  * Copyright 2012-2013 smartics, Kronseder & Reiner GmbH

  *

  * 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 de.smartics.properties.reports;

 import java.io.OutputStream;

 import org.apache.commons.configuration.ConfigurationException;

 import org.apache.commons.configuration.PropertiesConfiguration;

 import de.smartics.properties.api.core.domain.PropertyDescriptor;

 import de.smartics.properties.api.core.domain.PropertyExpression;

 import de.smartics.properties.report.app.ReportException;

 import de.smartics.properties.report.data.PropertyReportItem;

 import de.smartics.properties.report.data.PropertyReportSet;

 import de.smartics.util.lang.Arg;

 /**

  * Stores every report item in a property set.

  */

 public final class PropertiesPropertyReport extends AbstractPropertyReport

 {

   // ********************************* Fields *********************************

   // --- constants ------------------------------------------------------------

   // --- members --------------------------------------------------------------

   /**

    * The current comment to prepend to the collected properties.

    */

   private String currentComment;

   /**

    * The currently collected properties.

    */

   private final PropertiesConfiguration currentProperties =

       new PropertiesConfiguration();

   /**

    * The stream to write to.

    */

   private final OutputStream output;

   // ****************************** Initializer *******************************

   // ****************************** Constructors ******************************

   /**

    * Constructor.

    *

    * @param output the stream to write to.

    * @see de.smartics.properties.reports.AbstractPropertyReport#AbstractPropertyReport()

    */

   public PropertiesPropertyReport(final OutputStream output)

   {

     this.output = Arg.checkNotNull("output", output);

   }

   // ****************************** Inner Classes *****************************

   // ********************************* Methods ********************************

   // --- init -----------------------------------------------------------------

   // --- get&set --------------------------------------------------------------

   // --- business -------------------------------------------------------------

   @Override

   public void handle(final PropertyReportSet reportSet) throws ReportException

   {

     flush(reportSet.getName());

     final StringBuilder buffer = new StringBuilder(256);

     buffer.append(reportSet.getName()).append('\n')

         .append(reportSet.getComment());

     currentComment = buffer.toString();

   }

   private void flush(final String name) throws ReportException

   {

     if (!currentProperties.isEmpty())

     {

       try

       {

         currentProperties.setHeader(currentComment);

         currentProperties.save(output, "ISO8859-1");

       }

       catch (final ConfigurationException e)

       {

         final String message =

             name != null ? "Cannot write report set '" + name + "'."

                 : "Cannot flush.";

         throw new ReportException(message, e);

       }

       currentProperties.clear();

     }

   }

   @Override

   public void handle(final PropertyReportItem item) throws ReportException

   {

     super.handle(item);

     final PropertyDescriptor descriptor = item.getDescriptor();

     final String key = descriptor.getKey().toString();

     final PropertyExpression expression = descriptor.getDefaultExpression();

     final String value =

         expression != null && expression.getExpression() != null ? expression

             .getExpression() : "";

     currentProperties.setProperty(key, value);

   }

   /**

    * Flushes the latest report set and items.

    */

   public void flush()

   {

     flush(null);

   }

   // --- object basics --------------------------------------------------------

 }