/*

  * 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.myfaces.flow.cdi;

 import java.util.ArrayList;

 import java.util.List;

 import javax.enterprise.event.Observes;

 import javax.enterprise.inject.spi.AnnotatedType;

 import javax.enterprise.inject.spi.BeanManager;

 import javax.enterprise.inject.spi.BeforeBeanDiscovery;

 import javax.enterprise.inject.spi.Extension;

 import javax.enterprise.inject.spi.ProcessProducer;

 import javax.enterprise.inject.spi.Producer;

 import javax.faces.flow.Flow;

 import javax.faces.flow.builder.FlowDefinition;

 /**

  * This extension is responsible of scan flow definitions through CDI. For example:

  *

  * <code>

  * @Produces @FlowDefinition

  * public Flow defineFlow(@FlowBuilderParameter FlowBuilder flowBuilder) {...}

  * </code>

  *

  * @author Leonardo Uribe

  */

 public class FlowBuilderCDIExtension implements Extension

 {

     private List<Producer<Flow>> flowProducers = new ArrayList<Producer<Flow>>();

     public List<Producer<Flow>> getFlowProducers()

     {

         return flowProducers;

     }

     void beforeBeanDiscovery(

         @Observes final BeforeBeanDiscovery event, BeanManager beanManager)

     {

         // Register FlowBuilderFactoryBean as a bean with CDI annotations, so the system

         // can take it into account, and use it later when necessary.

         AnnotatedType<FlowBuilderFactoryBean> flowDiscoveryHelper =

                         beanManager.createAnnotatedType(FlowBuilderFactoryBean.class);

         event.addAnnotatedType(flowDiscoveryHelper);

     }

     /**

      * Stores any producer method that is annotated with @FlowDefinition.

      */

     <T> void findFlowDefinition(@Observes ProcessProducer<T, Flow> processProducer)

     {

         if (processProducer.getAnnotatedMember().isAnnotationPresent(FlowDefinition.class))

         {

             flowProducers.add(processProducer.getProducer());

         }

     }

 }