/*
    * 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.Iterator;
  import java.util.List;
  import java.util.Map;
  import java.util.logging.Level;
  import java.util.logging.Logger;
  import javax.enterprise.inject.spi.BeanManager;
  import javax.faces.context.FacesContext;
  import javax.faces.flow.Flow;
  import org.apache.myfaces.cdi.util.CDIUtils;
  import org.apache.myfaces.flow.util.FlowUtils;
  import org.apache.myfaces.spi.FacesFlowProvider;
  
  /**
   *
   * @author Leonardo Uribe
   */
  public class DefaultCDIFacesFlowProvider extends FacesFlowProvider
  {
      private BeanManager _beanManager;
      private boolean _initialized;
      
      private final static String CURRENT_FLOW_SCOPE_MAP = "oam.flow.SCOPE_MAP";
      
      static final char SEPARATOR_CHAR = '.';
      
      @Override
      public Iterator<Flow> getAnnotatedFlows(FacesContext facesContext)
      {
          BeanManager beanManager = getBeanManager(facesContext);
          if (beanManager != null)
          {
              FlowBuilderFactoryBean bean = CDIUtils.lookup(
                  beanManager, FlowBuilderFactoryBean.class);
  
              List<Flow> flows = bean.getFlowDefinitions();
              
              return flows.iterator();
          }
          else
          {
              Logger.getLogger(DefaultCDIFacesFlowProvider.class.getName()).log(Level.INFO,
                  "CDI BeanManager not found");
          }
          return null;
      }
      
      @Override
      public void doAfterEnterFlow(FacesContext context, Flow flow)
      {
          BeanManager beanManager = getBeanManager(context);
          if (beanManager != null)
          {
              FlowScopeBeanHolder beanHolder = CDIUtils.lookup(beanManager, FlowScopeBeanHolder.class);
              beanHolder.createCurrentFlowScope(context);
          }
          String mapKey = CURRENT_FLOW_SCOPE_MAP+SEPARATOR_CHAR+
                  flow.getDefiningDocumentId()+SEPARATOR_CHAR+flow.getId();
          context.getAttributes().remove(mapKey);
      }
      
      @Override
      public void doBeforeExitFlow(FacesContext context, Flow flow)
      {
          BeanManager beanManager = getBeanManager(context);
          if (beanManager != null)
          {
              FlowScopeBeanHolder beanHolder = CDIUtils.lookup(beanManager, FlowScopeBeanHolder.class);
              beanHolder.destroyCurrentFlowScope(context);
          }
          String mapKey = CURRENT_FLOW_SCOPE_MAP+SEPARATOR_CHAR+
                  flow.getDefiningDocumentId()+SEPARATOR_CHAR+flow.getId();
          context.getAttributes().remove(mapKey);
      }
      
      public Map<Object, Object> getCurrentFlowScope(FacesContext facesContext)
      {
          Flow flow = facesContext.getApplication().getFlowHandler().getCurrentFlow(facesContext);
          if (flow != null)
          {
             String mapKey = CURRENT_FLOW_SCOPE_MAP+SEPARATOR_CHAR+
                 flow.getDefiningDocumentId()+SEPARATOR_CHAR+flow.getId();
             Map<Object, Object> map = (Map<Object, Object>) facesContext.getAttributes().get(
                 mapKey);
             if (map == null)
             {
                 map = new FlowScopeMap(getBeanManager(), FlowUtils.getFlowMapKey(facesContext, flow));
                 
                 facesContext.getAttributes().put(mapKey, map);
             }
             return map;
         }
         return null;
     }
 
     @Override
     public void refreshClientWindow(FacesContext facesContext)
     {
         if (!facesContext.getApplication().getStateManager().isSavingStateInClient(facesContext))
         {
             Flow flow = facesContext.getApplication().getFlowHandler().getCurrentFlow(facesContext);
             if (flow != null)
             {
                 BeanManager beanManager = getBeanManager(facesContext);
                 if (beanManager != null)
                 {
                     FlowScopeBeanHolder beanHolder = CDIUtils.lookup(beanManager, FlowScopeBeanHolder.class);
 
                     //Refresh client window for flow scope
                     beanHolder.refreshClientWindow(facesContext);
                 }
             }
         }
     }
     
     public BeanManager getBeanManager()
     {
         if (_beanManager == null && !_initialized)
         {
             _beanManager = CDIUtils.getBeanManager(
                 FacesContext.getCurrentInstance().getExternalContext());
             _initialized = true;
         }
         return _beanManager;
     }
     
     public BeanManager getBeanManager(FacesContext facesContext)
     {
         if (_beanManager == null && !_initialized)
         {
             _beanManager = CDIUtils.getBeanManager(
                 facesContext.getExternalContext());
             _initialized = true;
         }
         return _beanManager;
     }
 
 }