/*
    * 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.cdi.view;
  
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.HashSet;
  import java.util.List;
  import java.util.Map;
  import java.util.Set;
  import javax.enterprise.inject.spi.BeanManager;
  import javax.faces.context.FacesContext;
  import org.apache.myfaces.cdi.util.CDIUtils;
  import org.apache.myfaces.cdi.util.ContextualInstanceInfo;
  
  /**
   *
   * @author Leonardo Uribe
   */
  public class ViewScopeCDIMap implements Map<String, Object>
  {
      private String _viewScopeId;
      
      private ViewScopeContextualStorage storage;
  
      public ViewScopeCDIMap(FacesContext facesContext)
      {
          BeanManager beanManager = CDIUtils.getBeanManager(facesContext.getExternalContext());
  
          ViewScopeBeanHolder bean = CDIUtils.lookup(beanManager, ViewScopeBeanHolder.class);
  
          // 1. get a new view scope id
          _viewScopeId = bean.generateUniqueViewScopeId();
  
          storage = bean.getContextualStorage(beanManager, _viewScopeId);
      }
      
      public ViewScopeCDIMap(FacesContext facesContext, String viewScopeId)
      {
          BeanManager beanManager = CDIUtils.getBeanManager(facesContext.getExternalContext());
  
          ViewScopeBeanHolder bean = CDIUtils.lookup(beanManager, ViewScopeBeanHolder.class);
  
          // 1. get a new view scope id
          _viewScopeId = viewScopeId;
  
          storage = bean.getContextualStorage(beanManager, _viewScopeId);
      }
      
      private ViewScopeContextualStorage getStorage()
      {
          if (storage != null && !storage.isActive())
          {
              storage = null;
          }
          if (storage == null)
          {
              FacesContext facesContext = FacesContext.getCurrentInstance();
              BeanManager beanManager = CDIUtils.getBeanManager(facesContext.getExternalContext());
  
              ViewScopeBeanHolder bean = CDIUtils.lookup(beanManager, ViewScopeBeanHolder.class);
              
              storage = bean.getContextualStorage(beanManager, _viewScopeId);
          }
          return storage;
      }
      
      private Map<String, Object> getNameBeanKeyMap()
      {
          return getStorage().getNameBeanKeyMap();
      }
      
      private Map<Object, ContextualInstanceInfo<?>> getCreationalContextInstances()
      {
          return getStorage().getStorage();
      }
      
      public String getViewScopeId()
      {
          return _viewScopeId;
      }
      
      @Override
     public int size()
     {
         return this.getNameBeanKeyMap().size();
     }
 
     @Override
     public boolean isEmpty()
     {
         return this.getNameBeanKeyMap().isEmpty();
     }
 
     @Override
     public boolean containsKey(Object key)
     {
         return this.getNameBeanKeyMap().containsKey(key);
     }
 
     @Override
     public boolean containsValue(Object value)
     {
         if (value != null)
         {
             for (Map.Entry<Object, ContextualInstanceInfo<?>> entry : getCreationalContextInstances().entrySet())
             {
                 if (entry.getValue() != null && value.equals(entry.getValue().getContextualInstance()))
                 {
                     return true;
                 }
             }
         }
         return false;
     }
 
     @Override
     public Object get(Object key)
     {
         Object beanKey = this.getNameBeanKeyMap().get(key);
         if (beanKey != null)
         {
             ContextualInstanceInfo<?> info = this.getCreationalContextInstances().get(beanKey);
             return info == null ? null : info.getContextualInstance();
         }
         return null;
     }
 
     @Override
     public Object put(String key, Object value)
     {
         Object beanKey = new ViewScopeContextualKey(key);
         this.getNameBeanKeyMap().put(key, beanKey);
         ContextualInstanceInfo info = new ContextualInstanceInfo();
         info.setContextualInstance(value);
         return this.getCreationalContextInstances().put(beanKey, info);
     }
 
     @Override
     public Object remove(Object key)
     {
         Object beanKey = this.getNameBeanKeyMap().remove(key);
         ContextualInstanceInfo info = this.getCreationalContextInstances().remove(beanKey);
         return info == null ? null : info.getContextualInstance();
     }
 
     @Override
     public void putAll(Map<? extends String, ? extends Object> m)
     {
         for (Map.Entry<? extends String, ? extends Object> entry : m.entrySet())
         {
             put(entry.getKey(), entry.getValue());
         }
     }
 
     @Override
     public void clear()
     {
         boolean destroyed = false;
         // If the scope was already destroyed through an invalidateSession(), the storage instance
         // that is holding this map could be obsolete, so we need to grab the right instance from
         // the bean holder.
         FacesContext facesContext = FacesContext.getCurrentInstance();
         if (facesContext != null)
         {
             BeanManager beanManager = CDIUtils.getBeanManager(facesContext.getExternalContext());
 
             if (beanManager != null)
             {
                 ViewScopeBeanHolder bean = CDIUtils.lookup(beanManager, ViewScopeBeanHolder.class);
                 if (bean != null)
                 {
                     ViewScopeContextualStorage st = bean.getContextualStorage(beanManager, _viewScopeId);
                     if (st != null)
                     {
                         ViewScopeContextImpl.destroyAllActive(st);
                         storage = null;
                         destroyed = true;
                     }
                 }
             }
         }
         if (!destroyed)
         {
             ViewScopeContextImpl.destroyAllActive(storage);
         }
     }
 
     @Override
     public Set<String> keySet()
     {
         return this.getNameBeanKeyMap().keySet();
     }
 
     @Override
     public Collection<Object> values()
     {
         List<Object> values = new ArrayList<Object>(this.getNameBeanKeyMap().size());
         for (Map.Entry<String, Object> entry : this.getNameBeanKeyMap().entrySet())
         {
             if (entry.getValue() != null)
             {
                 ContextualInstanceInfo info = this.getCreationalContextInstances().get(entry.getValue());
                 if (info != null)
                 {
                     values.add(info.getContextualInstance());
                 }
             }
         }
         return values;
     }
 
     @Override
     public Set<Entry<String, Object>> entrySet()
     {
         Set<Entry<String, Object>> values = new HashSet<Entry<String, Object>>();
         for (Map.Entry<String, Object> entry : this.getNameBeanKeyMap().entrySet())
         {
             if (entry.getValue() != null)
             {
                 ContextualInstanceInfo info = this.getCreationalContextInstances().get(entry.getValue());
                 if (info != null)
                 {
                     values.add(new EntryWrapper(entry));
                 }
             }
         }
         return values;
     }
     
     private class EntryWrapper<String, Object> implements Entry<String, Object>
     {
         private Map.Entry<String, Object> entry;
         
         public EntryWrapper(Map.Entry<String, Object> entry)
         {
             this.entry = entry;
         }
 
         @Override
         public String getKey()
         {
             return entry.getKey();
         }
 
         @Override
         public Object getValue()
         {
             ContextualInstanceInfo<?> info = getCreationalContextInstances().get(entry.getValue());
             return (Object) (info == null ? null : info.getContextualInstance());
         }
 
         @Override
         public Object setValue(Object value)
         {
             ContextualInstanceInfo info = getCreationalContextInstances().get(entry.getValue());
             Object oldValue = null;
             if (info != null)
             {
                 info.setContextualInstance(value);
             }
             else
             {
                 info = new ContextualInstanceInfo();
                 info.setContextualInstance(value);
                 getCreationalContextInstances().put(entry.getValue(), info);
             }
             return oldValue;
         }
     }
 }