/*
    * Copyright 2015 Data Archiving and Networked Services (an institute of
    * Koninklijke Nederlandse Akademie van Wetenschappen), King's College London,
    * Georg-August-Universitaet Goettingen Stiftung Oeffentlichen Rechts
    *
    * Licensed under the EUPL, Version 1.1 or – as soon they will be approved by
    * the European Commission - subsequent versions of the EUPL (the "Licence");
    * You may not use this work except in compliance with the Licence.
    * You may obtain a copy of the Licence at:
   *
   * https://joinup.ec.europa.eu/software/page/eupl
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the Licence is distributed on an "AS IS" basis,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the Licence for the specific language governing
   * permissions and limitations under the Licence.
   */
  
  package eu.ehri.extension;
  
  import eu.ehri.extension.base.AbstractAccessibleResource;
  import eu.ehri.extension.base.AbstractResource;
  import eu.ehri.extension.base.DeleteResource;
  import eu.ehri.extension.base.GetResource;
  import eu.ehri.extension.base.ListResource;
  import eu.ehri.extension.base.UpdateResource;
  import eu.ehri.project.core.Tx;
  import eu.ehri.project.definitions.Entities;
  import eu.ehri.project.exceptions.DeserializationError;
  import eu.ehri.project.exceptions.ItemNotFound;
  import eu.ehri.project.exceptions.PermissionDenied;
  import eu.ehri.project.exceptions.ValidationError;
  import eu.ehri.project.models.Link;
  import eu.ehri.project.models.UserProfile;
  import eu.ehri.project.persistence.Bundle;
  import org.neo4j.graphdb.GraphDatabaseService;
  
  import javax.ws.rs.Consumes;
  import javax.ws.rs.DELETE;
  import javax.ws.rs.GET;
  import javax.ws.rs.POST;
  import javax.ws.rs.PUT;
  import javax.ws.rs.Path;
  import javax.ws.rs.PathParam;
  import javax.ws.rs.Produces;
  import javax.ws.rs.QueryParam;
  import javax.ws.rs.core.Context;
  import javax.ws.rs.core.MediaType;
  import javax.ws.rs.core.Response;
  import java.util.List;
  
  /**
   * Provides a web service interface for creating/reading item links.
   */
  @Path(AbstractResource.RESOURCE_ENDPOINT_PREFIX + "/" + Entities.LINK)
  public class LinkResource extends AbstractAccessibleResource<Link>
          implements GetResource, ListResource, DeleteResource, UpdateResource {
  
      public static final String TARGET_PARAM = "target";
      public static final String SOURCE_PARAM = "source";
      public static final String BODY_PARAM = "body";
  
      public LinkResource(@Context GraphDatabaseService database) {
          super(database, Link.class);
      }
  
      @GET
      @Produces(MediaType.APPLICATION_JSON)
      @Path("{id:[^/]+}")
      @Override
      public Response get(@PathParam("id") String id) throws ItemNotFound {
          return getItem(id);
      }
  
      @GET
      @Produces(MediaType.APPLICATION_JSON)
      public Response list() {
          return listItems();
      }
  
      @PUT
      @Path("{id:[^/]+}")
      @Override
      public Response update(@PathParam("id") String id, Bundle bundle)
              throws PermissionDenied, ItemNotFound, ValidationError, DeserializationError {
          try (final Tx tx = beginTx()) {
              Response item = updateItem(id, bundle);
              tx.success();
              return item;
          }
      }
  
      /**
       * Create a link between two items.
       *
       * @param bundle    The link body data
       * @param source    The link source
       * @param target    The link target
      * @param bodies    optional list of entities to provide the body
      * @param accessors The IDs of accessors who can see this link
      * @return the created link item
      */
     @POST
     @Consumes(MediaType.APPLICATION_JSON)
     @Produces(MediaType.APPLICATION_JSON)
     public Response create(
             Bundle bundle,
             @QueryParam(SOURCE_PARAM) String source,
             @QueryParam(TARGET_PARAM) String target,
             @QueryParam(BODY_PARAM) List<String> bodies,
             @QueryParam(ACCESSOR_PARAM) List<String> accessors)
             throws PermissionDenied, ValidationError,
             DeserializationError, ItemNotFound {
         try (final Tx tx = beginTx()) {
             if (source == null || target == null) {
                 throw new DeserializationError("Both source and target must be provided");
             }
             UserProfile user = getCurrentUser();
             Link link = api().createLink(target,
                     source, bodies, bundle, getAccessors(accessors, user), getLogMessage());
             Response response = creationResponse(link);
             tx.success();
             return response;
         }
     }
 
     @DELETE
     @Path("{id:[^/]+}")
     @Override
     public void delete(@PathParam("id") String id)
             throws PermissionDenied, ItemNotFound, ValidationError {
         try (final Tx tx = beginTx()) {
             deleteItem(id);
             tx.success();
         }
     }
 }