/*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you 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 org.apache.syncope.core.flowable.support;
  
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  import java.util.Objects;
  import javax.annotation.PreDestroy;
  import javax.sql.DataSource;
  import org.apache.syncope.core.persistence.api.DomainHolder;
  import org.apache.syncope.core.persistence.api.SyncopeCoreLoader;
  import org.flowable.common.engine.impl.cfg.SpringBeanFactoryProxyMap;
  import org.flowable.engine.ProcessEngine;
  import org.flowable.engine.impl.el.ProcessExpressionManager;
  import org.flowable.engine.impl.util.EngineServiceUtil;
  import org.flowable.idm.spring.SpringIdmEngineConfiguration;
  import org.flowable.spring.SpringProcessEngineConfiguration;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import org.springframework.beans.factory.FactoryBean;
  import org.springframework.context.ApplicationContext;
  import org.springframework.transaction.PlatformTransactionManager;
  
  /**
   * Spring factory for {@link DomainProcessEngine} which takes the provided {@link SpringProcessEngineConfiguration} as
   * template for each of the configured Syncope domains.
   */
  public class DomainProcessEngineFactoryBean implements FactoryBean<DomainProcessEngine>, SyncopeCoreLoader {
  
      private static final Logger LOG = LoggerFactory.getLogger(DomainProcessEngineFactoryBean.class);
  
      private final ApplicationContext ctx;
  
      private DomainProcessEngine engine;
  
      public DomainProcessEngineFactoryBean(final ApplicationContext ctx) {
          this.ctx = ctx;
      }
  
      @Override
      public int getOrder() {
          return 300;
      }
  
      private ProcessEngine build(final String domain, final DataSource datasource) {
          PlatformTransactionManager transactionManager = ctx.getBean(
                  domain + "TransactionManager", PlatformTransactionManager.class);
          Object entityManagerFactory = ctx.getBean(domain + "EntityManagerFactory");
  
          SpringProcessEngineConfiguration conf = ctx.getBean(SpringProcessEngineConfiguration.class);
          conf.setDataSource(datasource);
          conf.setTransactionManager(transactionManager);
          conf.setTransactionsExternallyManaged(true);
          conf.setJpaEntityManagerFactory(entityManagerFactory);
          if (conf.getBeans() == null) {
              conf.setBeans(new SpringBeanFactoryProxyMap(ctx));
          }
          if (conf.getExpressionManager() == null) {
              conf.setExpressionManager(new ProcessExpressionManager(conf.getBeans()));
          }
          if (EngineServiceUtil.getIdmEngineConfiguration(conf) == null) {
              SpringIdmEngineConfiguration spiec = ctx.getBean(SpringIdmEngineConfiguration.class);
              conf.addEngineConfiguration(spiec.getEngineCfgKey(), spiec.getEngineScopeType(), spiec);
          }
          conf.setEnableSafeBpmnXml(true);
          conf.setCustomFormTypes(List.of(new DropdownFormType(null), new PasswordFormType()));
          conf.setDisableEventRegistry(true);
  
          return conf.buildProcessEngine();
      }
  
      @Override
      public void load(final String domain, final DataSource datasource) {
          try {
              Objects.requireNonNull(getObject()).getEngines().put(domain, build(domain, datasource));
          } catch (Exception e) {
              LOG.error("Could not setup Flowable for {}", domain, e);
          }
      }
  
      @Override
      public DomainProcessEngine getObject() throws Exception {
         if (engine == null) {
             Map<String, ProcessEngine> engines = new HashMap<>();
 
             ctx.getBean(DomainHolder.class).getDomains().forEach(
                     (domain, datasource) -> engines.put(domain, build(domain, datasource)));
 
             engine = new DomainProcessEngine(engines);
         }
 
         return engine;
     }
 
     @Override
     public Class<DomainProcessEngine> getObjectType() {
         return DomainProcessEngine.class;
     }
 
     @Override
     public boolean isSingleton() {
         return true;
     }
 
     @PreDestroy
     public void preDestroy() {
         if (engine != null) {
             engine.close();
         }
     }
 }