/*
    * Licensed to The Apereo Foundation under one or more contributor license
    * agreements. See the NOTICE file distributed with this work for additional
    * information regarding copyright ownership.
    *
    *
    * The Apereo Foundation licenses this file to you under the Educational
    * Community 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://opensource.org/licenses/ecl2.txt
   *
   * 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 org.opencastproject.authorization.xacml.manager.endpoint;
  
  import static javax.servlet.http.HttpServletResponse.SC_BAD_REQUEST;
  import static javax.servlet.http.HttpServletResponse.SC_CONFLICT;
  import static javax.servlet.http.HttpServletResponse.SC_INTERNAL_SERVER_ERROR;
  import static javax.servlet.http.HttpServletResponse.SC_NOT_FOUND;
  import static javax.servlet.http.HttpServletResponse.SC_OK;
  import static org.opencastproject.util.RestUtil.R.conflict;
  import static org.opencastproject.util.RestUtil.R.noContent;
  import static org.opencastproject.util.RestUtil.R.notFound;
  import static org.opencastproject.util.RestUtil.R.ok;
  import static org.opencastproject.util.RestUtil.R.serverError;
  import static org.opencastproject.util.data.Monadics.mlist;
  import static org.opencastproject.util.doc.rest.RestParameter.Type.BOOLEAN;
  import static org.opencastproject.util.doc.rest.RestParameter.Type.INTEGER;
  import static org.opencastproject.util.doc.rest.RestParameter.Type.STRING;
  
  import org.opencastproject.assetmanager.api.AssetManager;
  import org.opencastproject.authorization.xacml.manager.api.AclService;
  import org.opencastproject.authorization.xacml.manager.api.AclServiceException;
  import org.opencastproject.authorization.xacml.manager.api.AclServiceFactory;
  import org.opencastproject.authorization.xacml.manager.api.ManagedAcl;
  import org.opencastproject.authorization.xacml.manager.impl.ManagedAclImpl;
  import org.opencastproject.mediapackage.MediaPackage;
  import org.opencastproject.mediapackage.MediaPackageException;
  import org.opencastproject.security.api.AccessControlList;
  import org.opencastproject.security.api.AccessControlParser;
  import org.opencastproject.security.api.AccessControlUtil;
  import org.opencastproject.security.api.AclScope;
  import org.opencastproject.security.api.AuthorizationService;
  import org.opencastproject.security.api.Organization;
  import org.opencastproject.security.api.SecurityService;
  import org.opencastproject.util.Jsons;
  import org.opencastproject.util.NotFoundException;
  import org.opencastproject.util.data.Function;
  import org.opencastproject.util.data.Option;
  import org.opencastproject.util.data.functions.Functions;
  import org.opencastproject.util.doc.rest.RestParameter;
  import org.opencastproject.util.doc.rest.RestQuery;
  import org.opencastproject.util.doc.rest.RestResponse;
  
  import org.apache.commons.lang3.StringUtils;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.util.Optional;
  
  import javax.ws.rs.DELETE;
  import javax.ws.rs.FormParam;
  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.WebApplicationException;
  import javax.ws.rs.core.MediaType;
  import javax.ws.rs.core.Response;
  
  public abstract class AbstractAclServiceRestEndpoint {
    private static final Logger logger = LoggerFactory.getLogger(AbstractAclServiceRestEndpoint.class);
  
    protected abstract AclServiceFactory getAclServiceFactory();
  
    protected abstract SecurityService getSecurityService();
  
    protected abstract AssetManager getAssetManager();
  
    protected abstract AuthorizationService getAuthorizationService();
  
    @GET
    @Path("/acl/{aclId}")
    @Produces(MediaType.APPLICATION_JSON)
    @RestQuery(
        name = "getacl",
        description = "Return the ACL by the given id",
        returnDescription = "Return the ACL by the given id",
        pathParameters = {
           @RestParameter(name = "aclId", isRequired = true, description = "The ACL identifier", type = INTEGER)
       },
       responses = {
           @RestResponse(responseCode = SC_OK, description = "The ACL has successfully been returned"),
           @RestResponse(responseCode = SC_NOT_FOUND, description = "The ACL has not been found"),
           @RestResponse(responseCode = SC_INTERNAL_SERVER_ERROR, description = "Error during returning the ACL")
       }
   )
   public String getAcl(@PathParam("aclId") long aclId) throws NotFoundException {
     final Optional<ManagedAcl> managedAcl = aclService().getAcl(aclId);
     if (managedAcl.isEmpty()) {
       logger.info("No ACL with id '{}' could be found", aclId);
       throw new NotFoundException();
     }
     return JsonConv.full(managedAcl.get()).toJson();
   }
 
   @POST
   @Path("/acl/extend")
   @Produces(MediaType.APPLICATION_JSON)
   @RestQuery(
       name = "extendacl",
       description = "Return the given ACL with a new role and action in JSON format",
       returnDescription = "Return the ACL with the new role and action in JSON format",
       restParameters = {
           @RestParameter(name = "acl", isRequired = true, description = "The access control list", type = STRING),
           @RestParameter(name = "action", isRequired = true, description = "The action for the ACL", type = STRING),
           @RestParameter(name = "role", isRequired = true, description = "The role for the ACL", type = STRING),
           @RestParameter(
               name = "allow",
               isRequired = true,
               description = "The allow status for the ACL",
               type = BOOLEAN
           )
       },
       responses = {
           @RestResponse(responseCode = SC_OK, description = "The ACL has successfully been returned"),
           @RestResponse(responseCode = SC_BAD_REQUEST, description = "The ACL, action or role was invalid or empty"),
           @RestResponse(responseCode = SC_INTERNAL_SERVER_ERROR, description = "Error during returning the ACL")
       }
   )
   public String extendAcl(
       @FormParam("acl") String accessControlList,
       @FormParam("action") String action,
       @FormParam("role") String role,
       @FormParam("allow") boolean allow
   ) {
     if (StringUtils.isBlank(accessControlList) || StringUtils.isBlank(action) || StringUtils.isBlank(role)) {
       throw new WebApplicationException(Response.Status.BAD_REQUEST);
     }
 
     AccessControlList acl = AccessControlUtil.extendAcl(parseAcl.apply(accessControlList), role, action, allow);
     return JsonConv.full(acl).toJson();
   }
 
   @POST
   @Path("/acl/reduce")
   @Produces(MediaType.APPLICATION_JSON)
   @RestQuery(
       name = "reduceacl",
       description = "Return the given ACL without a role and action in JSON format",
       returnDescription = "Return the ACL without the role and action in JSON format", restParameters = {
           @RestParameter(name = "acl", isRequired = true, description = "The access control list", type = STRING),
           @RestParameter(name = "action", isRequired = true, description = "The action for the ACL", type = STRING),
           @RestParameter(name = "role", isRequired = true, description = "The role for the ACL", type = STRING)
       },
       responses = {
           @RestResponse(responseCode = SC_OK, description = "The ACL has successfully been returned"),
           @RestResponse(responseCode = SC_BAD_REQUEST, description = "The ACL, role or action was invalid or empty"),
           @RestResponse(responseCode = SC_INTERNAL_SERVER_ERROR, description = "Error during returning the ACL")
       }
   )
   public String reduceAcl(
       @FormParam("acl") String accessControlList,
       @FormParam("action") String action,
       @FormParam("role") String role
   ) {
     if (StringUtils.isBlank(accessControlList) || StringUtils.isBlank(action) || StringUtils.isBlank(role)) {
       throw new WebApplicationException(Response.Status.BAD_REQUEST);
     }
 
     AccessControlList acl = AccessControlUtil.reduceAcl(parseAcl.apply(accessControlList), role, action);
     return JsonConv.full(acl).toJson();
   }
 
   @GET
   @Path("/acl/acls.json")
   @Produces(MediaType.APPLICATION_JSON)
   @RestQuery(
       name = "getacls",
       description = "Lists the ACL's as JSON",
       returnDescription = "The list of ACL's as JSON",
       responses = {
           @RestResponse(responseCode = SC_OK, description = "The list of ACL's has successfully been returned"),
           @RestResponse(
               responseCode = SC_INTERNAL_SERVER_ERROR,
               description = "Error during returning the list of ACL's"
           )
       }
   )
   public String getAcls() {
     return Jsons.arr(mlist(aclService().getAcls()).map(Functions.co(JsonConv.fullManagedAcl)))
             .toJson();
   }
 
   @POST
   @Path("/acl")
   @Produces(MediaType.APPLICATION_JSON)
   @RestQuery(
       name = "createacl",
       description = "Create an ACL",
       returnDescription = "Create an ACL",
       restParameters = {
           @RestParameter(name = "name", isRequired = true, description = "The ACL name", type = STRING),
           @RestParameter(name = "acl", isRequired = true, description = "The access control list", type = STRING)
       },
       responses = {
           @RestResponse(responseCode = SC_OK, description = "The ACL has successfully been added"),
           @RestResponse(responseCode = SC_CONFLICT, description = "An ACL with the same name already exists"),
           @RestResponse(responseCode = SC_BAD_REQUEST, description = "Unable to parse the ACL"),
           @RestResponse(responseCode = SC_INTERNAL_SERVER_ERROR, description = "Error during adding the ACL")
       }
   )
   public String createAcl(
       @FormParam("name") String name,
       @FormParam("acl") String accessControlList
   ) {
     final AccessControlList acl = parseAcl.apply(accessControlList);
     final Optional<ManagedAcl> managedAcl = aclService().createAcl(acl, name);
     if (managedAcl.isEmpty()) {
       logger.info("An ACL with the same name '{}' already exists", name);
       throw new WebApplicationException(Response.Status.CONFLICT);
     }
     return JsonConv.full(managedAcl.get()).toJson();
   }
 
   @PUT
   @Path("/acl/{aclId}")
   @Produces(MediaType.APPLICATION_JSON)
   @RestQuery(
       name = "updateacl",
       description = "Update an ACL",
       returnDescription = "Update an ACL",
       pathParameters = {
           @RestParameter(name = "aclId", isRequired = true, description = "The ACL identifier", type = INTEGER)
       },
       restParameters = {
           @RestParameter(name = "name", isRequired = true, description = "The ACL name", type = STRING),
           @RestParameter(name = "acl", isRequired = true, description = "The access control list", type = STRING)
       },
       responses = {
           @RestResponse(responseCode = SC_OK, description = "The ACL has successfully been updated"),
           @RestResponse(responseCode = SC_NOT_FOUND, description = "The ACL has not been found"),
           @RestResponse(responseCode = SC_BAD_REQUEST, description = "Unable to parse the ACL"),
           @RestResponse(responseCode = SC_INTERNAL_SERVER_ERROR, description = "Error during updating the ACL")
       }
   )
   public String updateAcl(
       @PathParam("aclId") long aclId,
       @FormParam("name") String name,
       @FormParam("acl") String accessControlList
   ) throws NotFoundException {
     final Organization org = getSecurityService().getOrganization();
     final AccessControlList acl = parseAcl.apply(accessControlList);
     final ManagedAclImpl managedAcl = new ManagedAclImpl(aclId, name, org.getId(), acl);
     if (!aclService().updateAcl(managedAcl)) {
       logger.info("No ACL with id '{}' could be found under organization '{}'", aclId, org.getId());
       throw new NotFoundException();
     }
     return JsonConv.full(managedAcl).toJson();
   }
 
   @DELETE
   @Path("/acl/{aclId}")
   @RestQuery(
       name = "deleteacl",
       description = "Delete an ACL",
       returnDescription = "Delete an ACL",
       pathParameters = {
           @RestParameter(name = "aclId", isRequired = true, description = "The ACL identifier", type = INTEGER)
       },
       responses = {
           @RestResponse(responseCode = SC_OK, description = "The ACL has successfully been deleted"),
           @RestResponse(responseCode = SC_NOT_FOUND, description = "The ACL has not been found"),
           @RestResponse(
               responseCode = SC_CONFLICT,
               description = "The ACL could not be deleted, there are still references on it"
           ),
           @RestResponse(responseCode = SC_INTERNAL_SERVER_ERROR, description = "Error during deleting the ACL")
       }
   )
   public Response deleteAcl(@PathParam("aclId") long aclId) throws NotFoundException {
     try {
       if (!aclService().deleteAcl(aclId)) {
         return conflict();
       }
     } catch (AclServiceException e) {
       logger.warn("Error deleting manged acl with id '{}'", aclId, e);
       throw new WebApplicationException(Response.Status.INTERNAL_SERVER_ERROR);
     }
     return noContent();
   }
 
   @POST
   @Path("/apply/episode/{episodeId}")
   @RestQuery(
           name = "applyAclToEpisode",
           description = "Immediate application of an ACL to an episode (Attention: This endpoint is deprecated and "
                   + " will be removed in future versions!)",
           returnDescription = "Status code",
           pathParameters = {
                   @RestParameter(name = "episodeId", isRequired = true, description = "The episode ID", type = STRING)
           },
           restParameters = {
                   @RestParameter(
                           name = "aclId",
                           isRequired = false,
                           description = "The ID of the ACL to apply. If missing the episode ACL will be "
                                   + "deleted to fall back to the series ACL",
                           type = INTEGER
                   )
           },
           responses = {
                   @RestResponse(responseCode = SC_OK, description = "The ACL has been successfully applied"),
                   @RestResponse(responseCode = SC_NOT_FOUND, description = "The ACL or the episode has not been found"),
                   @RestResponse(responseCode = SC_INTERNAL_SERVER_ERROR, description = "Internal error")
           }
   )
   public Response applyAclToEpisode(@PathParam("episodeId") String episodeId, @FormParam("aclId") Long aclId) {
     final AclService aclService = aclService();
     Optional<ManagedAcl> macl = aclService.getAcl(aclId);
     if (macl.isEmpty()) {
       return notFound();
     }
     try {
       Option<AccessControlList> aclOpt = Option.some(macl.get().getAcl());
       Optional<MediaPackage> mediaPackage = getAssetManager().getMediaPackage(episodeId);
       // the episode service is the source of authority for the retrieval of media packages
       if (mediaPackage.isPresent()) {
         MediaPackage episodeSvcMp = mediaPackage.get();
         aclOpt.fold(new Option.EMatch<AccessControlList>() {
           // set the new episode ACL
           @Override
           public void esome(final AccessControlList acl) {
             // update in episode service
             try {
               MediaPackage mp = getAuthorizationService().setAcl(episodeSvcMp, AclScope.Episode, acl).getA();
               getAssetManager().takeSnapshot(mp);
             } catch (MediaPackageException e) {
               logger.error("Error getting ACL from media package", e);
             }
           }
 
           // if none EpisodeACLTransition#isDelete returns true so delete the episode ACL
           @Override
           public void enone() {
             // update in episode service
             MediaPackage mp = getAuthorizationService().removeAcl(episodeSvcMp, AclScope.Episode);
             getAssetManager().takeSnapshot(mp);
           }
 
         });
         return ok();
       }
       // not found
       return notFound();
     } catch (Exception e) {
       logger.error("Error applying acl to episode {}", episodeId);
       return serverError();
     }
   }
 
   private static final Function<String, AccessControlList> parseAcl = new Function<String, AccessControlList>() {
     @Override
     public AccessControlList apply(String acl) {
       try {
         return AccessControlParser.parseAcl(acl);
       } catch (Exception e) {
         logger.warn("Unable to parse ACL");
         throw new WebApplicationException(Response.Status.BAD_REQUEST);
       }
     }
   };
 
   private AclService aclService() {
     return getAclServiceFactory().serviceFor(getSecurityService().getOrganization());
   }
 }