/*
    * 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.impl.persistence;
  
  import static org.opencastproject.authorization.xacml.manager.impl.persistence.ManagedAclEntity.findByIdAndOrgQuery;
  import static org.opencastproject.db.Queries.namedQuery;
  
  import org.opencastproject.authorization.xacml.manager.api.ManagedAcl;
  import org.opencastproject.authorization.xacml.manager.impl.AclDb;
  import org.opencastproject.db.DBSession;
  import org.opencastproject.db.DBSessionFactory;
  import org.opencastproject.security.api.AccessControlList;
  import org.opencastproject.security.api.Organization;
  import org.opencastproject.util.data.functions.Misc;
  
  import org.osgi.service.component.annotations.Activate;
  import org.osgi.service.component.annotations.Component;
  import org.osgi.service.component.annotations.Deactivate;
  import org.osgi.service.component.annotations.Reference;
  
  import java.util.List;
  import java.util.Optional;
  
  import javax.persistence.EntityManagerFactory;
  import javax.persistence.RollbackException;
  
  /** JPA based impl of an {@link org.opencastproject.authorization.xacml.manager.impl.AclDb}. */
  @Component(
          property = {
                  "service.description=JPA based ACL Provider"
          },
          immediate = true,
          service = { AclDb.class }
  )
  public final class JpaAclDb implements AclDb {
    private DBSessionFactory dbSessionFactory;
    private EntityManagerFactory emf;
    private DBSession db;
  
    @Activate
    public void activate() {
      db = dbSessionFactory.createSession(emf);
    }
  
    @Deactivate
    public synchronized void deactivate() {
      db.close();
    }
  
    @Reference
    public void setDBSessionFactory(DBSessionFactory dbSessionFactory) {
      this.dbSessionFactory = dbSessionFactory;
    }
  
    @Reference(target = "(osgi.unit.name=org.opencastproject.authorization.xacml.manager)")
    public void setEntityManagerFactory(EntityManagerFactory emf) {
      this.emf = emf;
    }
  
    @Override
    public List<ManagedAcl> getAcls(Organization org) {
      return Misc.widen(db.execTx(ManagedAclEntity.findByOrgQuery(org.getId())));
    }
  
    @Override
    public Optional<ManagedAcl> getAcl(Organization org, long id) {
      return Misc.widen(db.execTx(ManagedAclEntity.findByIdAndOrgQuery(org.getId(), id)));
    }
  
    @Override
    public boolean updateAcl(final ManagedAcl acl) {
      return db.execTx(em -> {
        Optional<ManagedAclEntity> e = findByIdAndOrgQuery(acl.getOrganizationId(), acl.getId()).apply(em);
        if (e.isEmpty()) {
          return false;
        }
        final ManagedAclEntity updated = e.get().update(acl.getName(), acl.getAcl(), acl.getOrganizationId());
        em.merge(updated);
        return true;
      });
   }
 
   @Override
   public Optional<ManagedAcl> createAcl(Organization org, AccessControlList acl, String name) {
     try {
       final ManagedAcl e = new ManagedAclEntity().update(name, acl, org.getId());
       return db.execTx(namedQuery.persistOpt(e));
     } catch (RollbackException e) {
       // DB exception handler that takes care of unique constraint violation and rethrows any other exception.
       final Throwable cause = e.getCause();
       String message = cause.getMessage().toLowerCase();
       if (message.contains("unique") || message.contains("duplicate")) {
         return Optional.empty();
       }
       throw e;
     }
   }
 
   @Override
   public boolean deleteAcl(Organization org, long id) {
     return db.execTx(ManagedAclEntity.deleteByIdAndOrgQuery(org.getId(), id)) > 0;
   }
 }