/*
    * 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.share;
  
  import java.net.URI;
  import java.util.ArrayList;
  import java.util.List;
  
  import javax.ws.rs.core.UriBuilder;
  import javax.ws.rs.core.UriInfo;
  
  import de.smartics.properties.admin.domain.model.ApiServices;
  import de.smartics.properties.admin.domain.model.AppRelations;
  import de.smartics.properties.admin.resources.controller.ApiResource;
  import de.smartics.properties.admin.resources.controller.PropertyDescriptorResource;
  import de.smartics.properties.admin.resources.controller.PropertyKeysResource;
  import de.smartics.properties.admin.resources.controller.PropertyResource;
  import de.smartics.resteasy.hypermedia.relations.Relations;
  import de.smartics.resteasy.hypermedia.renderer.LinkDescriptor;
  
  /**
   * A simple helper to create breadcrumbs.
   */
  public final class BreadcrumbHelper
  {
    // ********************************* Fields *********************************
  
    // --- constants ------------------------------------------------------------
  
    // --- members --------------------------------------------------------------
  
    /**
     * Creates link descriptors for the breadcrumbs.
     */
    private final LinkDescriptorFactory linkDescriptorFactory;
  
    /**
     * The method to select the service method of the resource.
     */
    private final String method;
  
    // ****************************** Initializer *******************************
  
    // ****************************** Constructors ******************************
  
    /**
     * Default constructor.
     *
     * @param linkDescriptorFactory the value for linkDescriptorFactory.
     * @param method the method to select the service method of the resource.
     */
    public BreadcrumbHelper(final LinkDescriptorFactory linkDescriptorFactory,
        final String method)
    {
      this.linkDescriptorFactory = linkDescriptorFactory;
      this.method = method;
    }
  
    // ****************************** Inner Classes *****************************
  
    // ********************************* Methods ********************************
  
    // --- init -----------------------------------------------------------------
  
    // --- get&set --------------------------------------------------------------
  
    // --- business -------------------------------------------------------------
  
    /**
     * Creates the link descriptor to the configurations services that is part of
     * the API.
     *
     * @param descriptor the descriptor of the service.
     * @return the link descriptor to the configurations services.
     */
    public LinkDescriptor service(final ApiServices.ServiceDescriptor descriptor)
    {
      final LinkDescriptor desc =
          linkDescriptorFactory.createDescriptor(descriptor, method);
      return desc;
    }
  
    /**
     * Returns the breadcrumbs for the view that shows the home page.
     *
     * @return the link of breadcrumb elements.
    */
   public List<LinkDescriptor> home()
   {
     final UriInfo uriInfo = linkDescriptorFactory.getUriInfo();
     final String full = uriInfo.getBaseUri().toString();
     final int index = full.lastIndexOf("/api");
     final UriBuilder builder = UriBuilder.fromPath(full.substring(0, index));
     final URI uri = builder.build();
     final LinkDescriptor desc =
         linkDescriptorFactory.createDescriptor("home", uri);
     desc.addRels(Relations.HOME);
 
     final List<LinkDescriptor> links = new ArrayList<LinkDescriptor>();
     links.add(desc);
     return links;
   }
 
   /**
    * Returns the breadcrumbs for the view that shows the list of services
    * provided by the API.
    *
    * @return the link of breadcrumb elements.
    */
   public List<LinkDescriptor> api()
   {
     final UriInfo uriInfo = linkDescriptorFactory.getUriInfo();
     final UriBuilder builder = uriInfo.getBaseUriBuilder();
     final URI uri = builder.build();
     final LinkDescriptor desc =
         linkDescriptorFactory.createDescriptor("api", uri);
     desc.addRels(AppRelations.API_HOME);
 
     final List<LinkDescriptor> links = home();
     links.add(desc);
     return links;
   }
 
   /**
    * Returns the breadcrumbs for the view that shows the list of property
    * descriptors.
    *
    * @return the link of breadcrumb elements.
    */
   public List<LinkDescriptor> descriptors()
   {
     final LinkDescriptor desc =
         linkDescriptorFactory.createDescriptor(ApiResource.DESCRIPTORS, method);
     desc.addRels(AppRelations.DESCRIPTORS);
 
     final List<LinkDescriptor> links = api();
     adjust(links);
     links.add(desc);
 
     return links;
   }
 
   /**
    * Returns the breadcrumbs for the view that shows a selected property
    * descriptor.
    *
    * @param propertyKey the selected property key.
    * @return the link of breadcrumb elements.
    */
   public List<LinkDescriptor> descriptor(final String propertyKey)
   {
     final LinkDescriptor desc =
         linkDescriptorFactory.createDescriptor("descriptor",
             PropertyDescriptorResource.class, method, propertyKey);
     desc.setShortLabel(propertyKey);
     desc.addRels(AppRelations.DESCRIPTOR);
 
     final List<LinkDescriptor> links = descriptors();
     adjust(links);
     links.add(desc);
 
     return links;
   }
 
   private static void adjust(final List<LinkDescriptor> links)
   {
     for (final LinkDescriptor link : links)
     {
       link.addRels(Relations.UP);
     }
   }
 
   /**
    * Adds the self relation to the last element in the list of links.
    *
    * @param links the links to adjust.
    * @return the adjusted links.
    */
   public static List<LinkDescriptor> adjustSelf(final List<LinkDescriptor> links)
   {
     final int lastIndex = links.size() - 1;
     if (lastIndex >= 0)
     {
       final LinkDescriptor link = links.get(lastIndex);
       link.addRels(Relations.SELF);
     }
 
     return links;
   }
 
   /**
    * Returns the breadcrumbs for the view that shows the list of configurations
    * by their keys.
    *
    * @return the link of breadcrumb elements.
    */
   public List<LinkDescriptor> configurations()
   {
     final LinkDescriptor desc =
         linkDescriptorFactory.createDescriptor(ApiResource.CONFIGURATIONS,
             method);
     desc.addRels(AppRelations.CONFIGURATIONS);
 
     final List<LinkDescriptor> links = api();
     adjust(links);
     links.add(desc);
 
     return links;
   }
 
   /**
    * Returns the breadcrumbs for the view that shows the list of properties by
    * their keys.
    *
    * @param configurationKey the key of the currently selected configuration.
    * @return the link of breadcrumb elements.
    */
   public List<LinkDescriptor> configuration(final String configurationKey)
   {
     final LinkDescriptor desc =
         linkDescriptorFactory.createDescriptor("configuration",
             PropertyKeysResource.class, method, configurationKey);
     desc.addRels(AppRelations.CONFIGURATION);
     desc.setShortLabel(configurationKey);
 
     final List<LinkDescriptor> links = configurations();
     adjust(links);
     links.add(desc);
 
     return links;
   }
 
   /**
    * Returns the breadcrumbs for the view that shows a single property.
    *
    * @param configurationKey the key of the currently selected configuration.
    * @param propertyKey the key of the currently selected property.
    * @return the link of breadcrumb elements.
    */
   public List<LinkDescriptor> property(final String configurationKey,
       final String propertyKey)
   {
     final LinkDescriptor desc =
         linkDescriptorFactory.createDescriptor("property",
             PropertyResource.class, method, configurationKey, propertyKey);
     desc.addRels(AppRelations.PROPERTY);
     desc.setShortLabel(propertyKey);
 
     final List<LinkDescriptor> links = configuration(configurationKey);
     adjust(links);
     links.add(desc);
 
     return links;
   }
 
   /**
    * Returns the breadcrumbs for the view that allows to en- and decrypt
    * property values.
    *
    * @return the link of breadcrumb elements.
    */
   public List<LinkDescriptor> security()
   {
     final LinkDescriptor desc =
         linkDescriptorFactory.createDescriptor(ApiResource.SECURITY, method);
     desc.addRels(AppRelations.SECURITY);
 
     final List<LinkDescriptor> links = api();
     adjust(links);
     links.add(desc);
 
     return links;
   }
 
   /**
    * Returns the breadcrumbs for the view that allows to configure JNDI
    * properties.
    *
    * @return the link of breadcrumb elements.
    */
   public List<LinkDescriptor> jndi()
   {
     final LinkDescriptor desc =
         linkDescriptorFactory.createDescriptor(ApiResource.JNDI, method);
     desc.addRels(AppRelations.JNDI);
 
     final List<LinkDescriptor> links = api();
     adjust(links);
     links.add(desc);
 
     return links;
   }
 
   // --- object basics --------------------------------------------------------
 
 }