# CommunityOfUsersResource.java

    /*
     * Copyright (C) 2000 - 2024 Silverpeas
     *
     * This program is free software: you can redistribute it and/or modify
     * it under the terms of the GNU Affero General Public License as
     * published by the Free Software Foundation, either version 3 of the
     * License, or (at your option) any later version.
     *
     * As a special exception to the terms and conditions of version 3.0 of
     * the GPL, you may redistribute this Program in connection with Free/Libre
     * Open Source Software ("FLOSS") applications as described in Silverpeas's
     * FLOSS exception.  You should have received a copy of the text describing
     * the FLOSS exception, and it is also available here:
     * "https://www.silverpeas.com/legal/licensing"
     *
     * This program is distributed in the hope that it will be useful,
     * but WITHOUT ANY WARRANTY; without even the implied warranty of
     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
     * GNU Affero General Public License for more details.
     *
     * You should have received a copy of the GNU Affero General Public License
     * along with this program.  If not, see <https://www.gnu.org/licenses/>.
     */
    package org.silverpeas.components.community.web;

    import org.silverpeas.components.community.model.CommunityOfUsers;
    import org.silverpeas.core.annotation.WebService;

    import javax.transaction.Transactional;
    import javax.ws.rs.BadRequestException;
    import javax.ws.rs.Consumes;
    import javax.ws.rs.GET;
    import javax.ws.rs.PUT;
    import javax.ws.rs.Path;
    import javax.ws.rs.PathParam;
    import javax.ws.rs.Produces;
    import javax.ws.rs.core.MediaType;
    import java.net.URI;

    import static java.util.Optional.ofNullable;

    /**
     * A REST-based Web resource representing the communities of users. A community is always related to
     * a resource in Silverpeas, and it is managed by a Community application instance. Only authorized
     * users can access these resources.
     */
    @WebService
    @Path(CommunityWebResource.RESOURCE_NAME + "/{componentInstanceId}")
    public class CommunityOfUsersResource extends CommunityWebResource {

      @PathParam("componentInstanceId")
      private String componentInstanceId;

      @Override
      public String getComponentId() {
        return componentInstanceId;
      }

      /**
       * Gets the JSON representation of the community of users  managed by the component instance of
       * id
       * <code>componentInstanceId</code>. If it doesn't exist, a 404 HTTP code is returned.
       * @return the JSON representation of a community resource.
       * @see WebProcess#execute()
       */
      @GET
      @Produces(MediaType.APPLICATION_JSON)
      public CommunityOfUsersEntity getCommunityOfUsers() {
        return process(this::asWebEntity);
      }

      /**
       * Updates the community of users with the properties of the specified web entity representing the
       * new state of the community. Because the space for which the community has been defined is
       * permanent and because the memberships of the community is handled by another resource (referred
       * by a URI), only data on the home page and the charter can be modified.
       * @param entity the new state of the community of users.
       * @return the JSON representation of the updated state of the community of users.
       */
      @PUT
      @Consumes(MediaType.APPLICATION_JSON)
      @Produces(MediaType.APPLICATION_JSON)
      @Transactional
      public CommunityOfUsersEntity updateCommunityOfUsers(final CommunityOfUsersEntity entity) {
        return process(community -> {
          checkValidity(entity, community);
          ofNullable(entity.getCharterURL()).ifPresentOrElse(
              community::setCharterURL,
              community::unsetCharterURL);
          community.setHomePage(entity.getHomePage().getFirst(), entity.getHomePage().getSecond());
          community.save();
          return asWebEntity(community);
        });
      }

      private void checkValidity(final CommunityOfUsersEntity entity,
          final CommunityOfUsers community) {
        var uriBuilder = getCommunityUriBuilder();
        URI communityURI = uriBuilder.getCommunityURI(community);
        URI membershipsURI = uriBuilder.getCommunityMembershipsURI(community);
        if (!community.getComponentInstanceId().equals(entity.getId()) ||
            !community.getSpaceId().equals(entity.getSpaceId()) ||
            !communityURI.equals(entity.getURI()) ||
            !membershipsURI.equals(entity.getMemberships())) {
          throw new BadRequestException(
              "The community entity doesn't match the community to update");
        }
      }

      private CommunityOfUsersEntity asWebEntity(final CommunityOfUsers community) {
        return CommunityOfUsersEntity.builder().with(community)
            .with(getCommunityUriBuilder())
            .build();
      }
    }