/*
    * Copyright 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.admin.resources.representation.xml;
  
  import java.io.OutputStream;
  import java.io.PrintStream;
  import java.io.UnsupportedEncodingException;
  import java.net.URI;
  import java.util.List;
  
  import javax.ws.rs.core.Link;
  
  import org.apache.commons.lang3.StringEscapeUtils;
  
  import de.smartics.properties.admin.domain.model.AppRelations;
  import de.smartics.properties.admin.domain.model.ConfigurationKeys;
  import de.smartics.properties.admin.resources.controller.PropertyKeysResource;
  import de.smartics.properties.admin.resources.representation.share.BreadcrumbHelper;
  import de.smartics.properties.admin.resources.representation.xml.share.AbstractXmlRepresentationRenderer;
  import de.smartics.properties.api.config.domain.key.ConfigurationKey;
  import de.smartics.resteasy.hypermedia.renderer.LinkDescriptor;
  import de.smartics.resteasy.hypermedia.renderer.LinkDescriptorJaxrs;
  import de.smartics.resteasy.hypermedia.renderer.LinkMetadata;
  import de.smartics.resteasy.hypermedia.renderer.ResourceContext;
  
  /**
   * Displays the list of configuration keys in an XML page.
   */
  public final class ConfigurationKeysXmlRepresentationRenderer extends
      AbstractXmlRepresentationRenderer<ConfigurationKeys>
  {
    // ********************************* Fields *********************************
  
    // --- constants ------------------------------------------------------------
  
    // --- members --------------------------------------------------------------
  
    /**
     * The domain object to render.
     */
    private final ConfigurationKeys domainObject;
  
    // ****************************** Initializer *******************************
  
    // ****************************** Constructors ******************************
  
    /**
     * Default constructor.
     *
     * @param context the context information to render the representation.
     * @param domainObject the domain object to render.
     * @param entityStream the stream to write to.
     */
    public ConfigurationKeysXmlRepresentationRenderer(
        final ResourceContext context, final ConfigurationKeys domainObject,
        final OutputStream entityStream)
    {
      super(context, entityStream);
      this.domainObject = domainObject;
    }
  
    // ****************************** Inner Classes *****************************
  
    // ********************************* Methods ********************************
  
    // --- init -----------------------------------------------------------------
  
    // --- get&set --------------------------------------------------------------
  
    // --- business -------------------------------------------------------------
  
    @Override
    protected void httpBody() throws IllegalStateException
    {
      final String encoding = context.getResponse().getCharacterEncoding();
      try
      {
        final PrintStream output = new PrintStream(entityStream, true, encoding);
        output.append("<?xml version=\"1.0\" encoding=\"").append(encoding)
            .append("\"?>\n\n");
  
        output.append("<configurations>\n");
        for (final ConfigurationKey<?> key : domainObject.getKeys())
        {
          final String keyString = key.toString();
          output.append("  <configuration id=\"")
             .append(StringEscapeUtils.escapeXml(keyString)).append("\">\n");
       }
 
       output.append("</configurations>\n");
     }
     catch (final UnsupportedEncodingException e)
     {
       throw new IllegalStateException(
           "Cannot write configurations to XML file due to unsupported encoding '"
               + encoding + "'.", e);
     }
   }
 
   @Override
   protected List<LinkDescriptor> hyperLinks()
   {
     final List<LinkDescriptor> links =
         BreadcrumbHelper.adjustSelf(breadcrumb.configurations());
 
     for (final ConfigurationKey<?> key : domainObject.getKeys())
     {
       final LinkDescriptor link = createLink(key.toString());
       links.add(link);
     }
 
     return links;
   }
 
   private LinkDescriptor createLink(final String key)
   {
     final URI uri =
         context.getUriInfo().getBaseUriBuilder()
             .path(PropertyKeysResource.class, "getAsXml")
             .build(new Object[] { key.toString() }, false);
     final Link link =
         Link.fromUri(uri).rel(AppRelations.CONFIGURATION + " " + key).build();
     final LinkMetadata metadata = new LinkMetadata();
 
     final LinkDescriptorJaxrs descriptor =
         new LinkDescriptorJaxrs(link, metadata);
     return descriptor;
   }
 
   @Override
   protected void close()
   {
   }
 
   // --- object basics --------------------------------------------------------
 
 }