/*
    * 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.view.facelets.tag.jsf;
  
  import java.io.IOException;
  import java.util.Collection;
  import java.util.Iterator;
  import java.util.Locale;
  import java.util.Map;
  
  import javax.faces.FacesException;
  import javax.faces.component.NamingContainer;
  import javax.faces.component.UIComponent;
  import javax.faces.component.UINamingContainer;
  import javax.faces.component.UIPanel;
  import javax.faces.component.UIViewRoot;
  import javax.faces.component.UniqueIdVendor;
  import javax.faces.context.FacesContext;
  import javax.faces.view.facelets.FaceletContext;
  import javax.faces.view.facelets.TagAttribute;
  import javax.faces.view.facelets.TagAttributeException;
  
  import org.apache.myfaces.shared.config.MyfacesConfig;
  import org.apache.myfaces.view.facelets.ComponentState;
  import org.apache.myfaces.view.facelets.DefaultFaceletsStateManagementStrategy;
  import org.apache.myfaces.view.facelets.FaceletCompositionContext;
  import org.apache.myfaces.view.facelets.FaceletViewDeclarationLanguage;
  
  /**
   * 
   * @author Jacob Hookom
   * @version $Id: ComponentSupport.java 1306710 2012-03-29 04:27:03Z lu4242 $
   */
  public final class ComponentSupport
  {
  
      private final static String MARK_DELETED = "oam.vf.MARK_DELETED";
      public final static String MARK_CREATED = "oam.vf.MARK_ID";
      
      /**
       * The UIPanel components, which are dynamically generated to serve as a container for
       * facets with multiple non panel children, are marked with this attribute.
       * This constant is duplicate in javax.faces.webapp.UIComponentClassicTagBase
       */
      public final static String FACET_CREATED_UIPANEL_MARKER = "oam.vf.createdUIPanel";
      
      /**
       * The key under the facelet state map is stored
       */
      public final static String FACELET_STATE_INSTANCE = "oam.FACELET_STATE_INSTANCE";
  
      /**
       * Used in conjunction with markForDeletion where any UIComponent marked will be removed.
       * 
       * @deprecated use FaceletCompositionContext.finalizeForDeletion
       * @param component
       *            UIComponent to finalize
       */
      @Deprecated
      public static void finalizeForDeletion(UIComponent component)
      {
          // remove any existing marks of deletion
          component.getAttributes().remove(MARK_DELETED);
  
          // finally remove any children marked as deleted
          if (component.getChildCount() > 0)
          {
              for (Iterator<UIComponent> iter = component.getChildren().iterator(); iter.hasNext();)
              {
                  UIComponent child = iter.next();
                  if (child.getAttributes().containsKey(MARK_DELETED))
                  {
                      iter.remove();
                  }
              }
          }
  
          // remove any facets marked as deleted
          Map<String, UIComponent> facets = component.getFacets();
          if (!facets.isEmpty())
          {
              Collection<UIComponent> col = facets.values();
              for (Iterator<UIComponent> itr = col.iterator(); itr.hasNext();)
             {
                 UIComponent fc = itr.next();
                 if (fc.getAttributes().containsKey(MARK_DELETED))
                 {
                     itr.remove();
                 }
             }
         }
     }
 
     /**
      * A lighter-weight version of UIComponent's findChild.
      * 
      * @param parent
      *            parent to start searching from
      * @param id
      *            to match to
      * @return UIComponent found or null
      */
     public static UIComponent findChild(UIComponent parent, String id)
     {
         int childCount = parent.getChildCount();
         if (childCount > 0)
         {
             for (int i = 0; i < childCount; i++)
             {
                 UIComponent child = parent.getChildren().get(i);
                 if (id.equals(child.getId()))
                 {
                     return child;
                 }
             }
         }
 
         return null;
     }
 
     /**
      * By TagId, find Child
      * 
      * @param parent
      * @param id
      * @return
      */
     public static UIComponent findChildByTagId(UIComponent parent, String id)
     {
         Iterator<UIComponent> itr = null;
         if (parent.getChildCount() > 0)
         {
             itr = parent.getChildren().iterator();
             while (itr.hasNext())
             {
                 UIComponent child = itr.next();
                 if (id.equals(child.getAttributes().get(MARK_CREATED)))
                 {
                     return child;
                 }
             }
         }
         if (parent.getFacetCount() > 0)
         {
             itr = parent.getFacets().values().iterator();
             while (itr.hasNext())
             {
                 UIComponent facet = itr.next();
                 // check if this is a dynamically generated UIPanel
                 if (Boolean.TRUE.equals(facet.getAttributes()
                              .get(FACET_CREATED_UIPANEL_MARKER)))
                 {
                     // only check the children and facets of the panel
                     Iterator<UIComponent> itr2 = facet.getFacetsAndChildren();
                     while (itr2.hasNext())
                     {
                         UIComponent child = itr2.next();
                         if (id.equals(child.getAttributes().get(MARK_CREATED)))
                         {
                             return child;
                         }
                     }
                 }
                 else if (id.equals(facet.getAttributes().get(MARK_CREATED)))
                 {
                     return facet;
                 }
             }
         }
 
         return null;
     }
 
     /**
      * According to JSF 1.2 tag specs, this helper method will use the TagAttribute passed in determining the Locale
      * intended.
      * 
      * @param ctx
      *            FaceletContext to evaluate from
      * @param attr
      *            TagAttribute representing a Locale
      * @return Locale found
      * @throws TagAttributeException
      *             if the Locale cannot be determined
      */
     public static Locale getLocale(FaceletContext ctx, TagAttribute attr) throws TagAttributeException
     {
         Object obj = attr.getObject(ctx);
         if (obj instanceof Locale)
         {
             return (Locale) obj;
         }
         if (obj instanceof String)
         {
             String s = (String) obj;
             if (s.length() == 2)
             {
                 return new Locale(s);
             }
 
             if (s.length() == 5)
             {
                 return new Locale(s.substring(0, 2), s.substring(3, 5).toUpperCase());
             }
 
             if (s.length() >= 7)
             {
                 return new Locale(s.substring(0, 2), s.substring(3, 5).toUpperCase(), s.substring(6, s.length()));
             }
 
             throw new TagAttributeException(attr, "Invalid Locale Specified: " + s);
         }
         else
         {
             throw new TagAttributeException(attr, "Attribute did not evaluate to a String or Locale: " + obj);
         }
     }
 
     /**
      * Tries to walk up the parent to find the UIViewRoot, if not found, then go to FaceletContext's FacesContext for
      * the view root.
      * 
      * @param ctx
      *            FaceletContext
      * @param parent
      *            UIComponent to search from
      * @return UIViewRoot instance for this evaluation
      */
     public static UIViewRoot getViewRoot(FaceletContext ctx, UIComponent parent)
     {
         UIComponent c = parent;
         do
         {
             if (c instanceof UIViewRoot)
             {
                 return (UIViewRoot) c;
             }
             else
             {
                 c = c.getParent();
             }
         } while (c != null);
 
         return ctx.getFacesContext().getViewRoot();
     }
     
     /**
      * Marks all direct children and Facets with an attribute for deletion.
      * 
      * @deprecated use FaceletCompositionContext.markForDeletion
      * @see #finalizeForDeletion(UIComponent)
      * @param component
      *            UIComponent to mark
      */
     @Deprecated
     public static void markForDeletion(UIComponent component)
     {
         // flag this component as deleted
         component.getAttributes().put(MARK_DELETED, Boolean.TRUE);
 
         Iterator<UIComponent> iter = component.getFacetsAndChildren();
         while (iter.hasNext())
         {
             UIComponent child = iter.next();
             if (child.getAttributes().containsKey(MARK_CREATED))
             {
                 child.getAttributes().put(MARK_DELETED, Boolean.TRUE);
             }
         }
     }
 
     public static void encodeRecursive(FacesContext context, UIComponent toRender) throws IOException, FacesException
     {
         if (toRender.isRendered())
         {
             toRender.encodeBegin(context);
             
             if (toRender.getRendersChildren())
             {
                 toRender.encodeChildren(context);
             }
             else if (toRender.getChildCount() > 0)
             {
                 for (int i = 0, childCount = toRender.getChildCount(); i < childCount; i++)
                 {
                     UIComponent child = toRender.getChildren().get(i);
                     encodeRecursive(context, child);
                 }
             }
             
             toRender.encodeEnd(context);
         }
     }
 
     public static void removeTransient(UIComponent component)
     {
         if (component.getChildCount() > 0)
         {
             for (Iterator<UIComponent> itr = component.getChildren().iterator(); itr.hasNext();)
             {
                 UIComponent child = itr.next();
                 if (child.isTransient())
                 {
                     itr.remove();
                 }
                 else
                 {
                     removeTransient(child);
                 }
             }
         }
         
         Map<String, UIComponent> facets = component.getFacets();
         if (!facets.isEmpty())
         {
             for (Iterator<UIComponent> itr = facets.values().iterator(); itr.hasNext();)
             {
                 UIComponent facet = itr.next();
                 if (facet.isTransient())
                 {
                     itr.remove();
                 }
                 else
                 {
                     removeTransient(facet);
                 }
             }
         }
     }
 
     /**
      * Determine if the passed component is not null and if it's new to the tree. This operation can be used for
      * determining if attributes should be wired to the component.
      * 
      * @deprecated use ComponentHandler.isNew
      * @param component
      *            the component you wish to modify
      * @return true if it's new
      */
     @Deprecated
     public static boolean isNew(UIComponent component)
     {
         return component != null && component.getParent() == null;
     }
     
     /**
      * Create a new UIPanel for the use as a dynamically 
      * created container for multiple children in a facet.
      * Duplicate in javax.faces.webapp.UIComponentClassicTagBase.
      * @param facesContext
      * @return
      */
     private static UIComponent createFacetUIPanel(FaceletContext ctx, UIComponent parent, String facetName)
     {
         FacesContext facesContext = ctx.getFacesContext();
         UIComponent panel = facesContext.getApplication().createComponent(UIPanel.COMPONENT_TYPE);
         
         // The panel created by this method is special. To be restored properly and do not
         // create duplicate ids or any other unwanted conflicts, it requires an unique id.
         // This code is usually called when more than one component is added to a facet and
         // it is necessary to create a shared container.
         // Use FaceletCompositionContext.generateUniqueComponentId() is not possible, because
         // <c:if> blocks inside a facet will make component ids unstable. Use UniqueIdVendor
         // is feasible but also will be affected by <c:if> blocks inside a facet.
         // The only solution that will generate real unique ids is use the parent id and the
         // facet name and derive an unique id that cannot be generated by SectionUniqueIdCounter,
         // doing the same trick as with metadata: use a double __ and add a prefix (f).
         // Note this id will never be printed into the response, because this is just a container.
         FaceletCompositionContext mctx = FaceletCompositionContext.getCurrentInstance(ctx);
         UniqueIdVendor uniqueIdVendor = mctx.getUniqueIdVendorFromStack();
         if (uniqueIdVendor == null)
         {
             uniqueIdVendor = ComponentSupport.getViewRoot(ctx, parent);
         }
         if (uniqueIdVendor != null)
         {
             // UIViewRoot implements UniqueIdVendor, so there is no need to cast to UIViewRoot
             // and call createUniqueId(). See ComponentTagHandlerDelegate
             int index = facetName.indexOf('.');
             String cleanFacetName = facetName;
             if (index >= 0)
             {
                 cleanFacetName = facetName.replace('.', '_');
             }
             panel.setId(uniqueIdVendor.createUniqueId(facesContext, 
                     mctx.getSharedStringBuilder()
                       .append(parent.getId())
                       .append("__f_")
                       .append(cleanFacetName).toString()));
         }
         panel.getAttributes().put(FACET_CREATED_UIPANEL_MARKER, Boolean.TRUE);
         return panel;
     }
     
     public static void addFacet(FaceletContext ctx, UIComponent parent, UIComponent c, String facetName)
     {
         // facets now can have multiple children and the direct
         // child of a facet is always an UIPanel (since 2.0)
         UIComponent facet = parent.getFacets().get(facetName);
         if (facet == null)
         {
             //Just set it directly like  before
             parent.getFacets().put(facetName, c);
         }
         else if (!(facet instanceof UIPanel))
         {
             // there is a facet, but it is not an instance of UIPanel
             UIComponent child = facet;
             facet = createFacetUIPanel(ctx, parent, facetName);
             facet.getChildren().add(child);
             facet.getChildren().add(c);
             parent.getFacets().put(facetName, facet);
         }
         else
         {
             // we have a facet, which is an instance of UIPanel at this point
             // check if it is a facet marked UIPanel
             if (Boolean.TRUE.equals(facet.getAttributes().get(FACET_CREATED_UIPANEL_MARKER)))
             {
                 facet.getChildren().add(c);
             }
             else
             {
                 // the facet is an instance of UIPanel, but it is not marked,
                 // so we have to create a new UIPanel and store this one in it
                 UIComponent oldPanel = facet;
                 facet = createFacetUIPanel(ctx, parent, facetName);
                 facet.getChildren().add(oldPanel);
                 facet.getChildren().add(c);
                 parent.getFacets().put(facetName, facet);
             }
         }
     }
     
     public static void removeFacet(FaceletContext ctx, UIComponent parent, UIComponent c, String facetName)
     {
         UIComponent facet = parent.getFacet(facetName);
         if (Boolean.TRUE.equals(facet.getAttributes().get(FACET_CREATED_UIPANEL_MARKER)))
         {
             facet.getChildren().remove(c);
         }
         else
         {
             parent.getFacets().remove(facetName);
         }
     }
 
     public static void markComponentToRestoreFully(FacesContext context, UIComponent component)
     {
         if (MyfacesConfig.getCurrentInstance(context.getExternalContext()).isRefreshTransientBuildOnPSSPreserveState())
         {
             component.getAttributes().put(DefaultFaceletsStateManagementStrategy.COMPONENT_ADDED_AFTER_BUILD_VIEW,
                                           ComponentState.REMOVE_ADD);
         }
         //component.subscribeToEvent(PostAddToViewEvent.class, new RestoreComponentFullyListener());
         if (FaceletViewDeclarationLanguage.isRefreshTransientBuildOnPSSAuto(context))
         {
             FaceletViewDeclarationLanguage.cleanTransientBuildOnRestore(context);
         }
     }
     
     public static UIComponent findComponentChildOrFacetFrom(FacesContext facesContext, UIComponent parent, String expr)
     {
         final char separatorChar = UINamingContainer.getSeparatorChar(facesContext);
         int separator = expr.indexOf(separatorChar);
         if (separator == -1)
         {
             return ComponentSupport.findComponentChildOrFacetFrom(
                     parent, expr, null);
         }
         else
         {
             return ComponentSupport.findComponentChildOrFacetFrom(
                     parent, expr.substring(0,separator), expr);
         }
     }
     
     public static UIComponent findComponentChildOrFacetFrom(UIComponent parent, String id, String innerExpr)
     {
         if (parent.getFacetCount() > 0)
         {
             for (UIComponent facet : parent.getFacets().values())
             {
                 if (id.equals(facet.getId()))
                 {
                     if (innerExpr == null)
                     {
                         return facet;
                     }
                     else if (facet instanceof NamingContainer)
                     {
                         UIComponent find = facet.findComponent(innerExpr);
                         if (find != null)
                         {
                             return find;
                         }
                     }
                 }
                 else if (!(facet instanceof NamingContainer))
                 {
                     UIComponent find = findComponentChildOrFacetFrom(facet, id, innerExpr);
                     if (find != null)
                     {
                         return find;
                     }
                 }
             }
         }
         if (parent.getChildCount() > 0)
         {
             for (int i = 0, childCount = parent.getChildCount(); i < childCount; i++)
             {
                 UIComponent child = parent.getChildren().get(i);
                 if (id.equals(child.getId()))
                 {
                     if (innerExpr == null)
                     {
                         return child;
                     }
                     else if (child instanceof NamingContainer)
                     {
                         UIComponent find = child.findComponent(innerExpr);
                         if (find != null)
                         {
                             return find;
                         }
                     }
                 }
                 else if (!(child instanceof NamingContainer))
                 {
                     UIComponent find = findComponentChildOrFacetFrom(child, id, innerExpr);
                     if (find != null)
                     {
                         return find;
                     }
                 }
             }
         }
         return null;
     }
     
     public static String getFindComponentExpression(FacesContext facesContext, UIComponent component)
     {
         char separatorChar = UINamingContainer.getSeparatorChar(facesContext);
         UIComponent parent = component.getParent();
         StringBuilder sb = new StringBuilder();
         sb.append(component.getId());
         while (parent != null)
         {
             if (parent instanceof NamingContainer)
             {
                 sb.insert(0, separatorChar);
                 sb.insert(0, parent.getId());
             }
             parent = parent.getParent();
         }
         return sb.toString();
     }
     
     public static Object restoreInitialTagState(FaceletContext ctx, FaceletCompositionContext fcc,
                                                 UIComponent parent, String uniqueId)
     {
         Object value = null;
         //if (fcc.isUsingPSSOnThisView() &&
         //    PhaseId.RESTORE_VIEW.equals(ctx.getFacesContext().getCurrentPhaseId()) &&
         //    !MyfacesConfig.getCurrentInstance(
         //            ctx.getFacesContext().getExternalContext()).isRefreshTransientBuildOnPSSPreserveState())
         if (fcc.isUsingPSSOnThisView() && !fcc.isRefreshTransientBuildOnPSSPreserveState())
         {
             UIViewRoot root = getViewRoot(ctx, parent);
             FaceletState map = (FaceletState) root.getAttributes().get(FACELET_STATE_INSTANCE);
             if (map == null)
             {
                 value = null;
             }
             else
             {
                 value = map.getState(uniqueId);
             }
         }
         return value;
     }
     
     public static void saveInitialTagState(FaceletContext ctx, FaceletCompositionContext fcc,
                                            UIComponent parent, String uniqueId, Object value)
     {
         // Only save the value when the view was built the first time, to ensure PSS algorithm 
         // work correctly. If preserve state is enabled, just ignore it, because this tag will
         // force full restore over the parent
         //if (fcc.isUsingPSSOnThisView()) {
         //    if (!fcc.isRefreshingTransientBuild() && !ctx.getFacesContext().isPostback()
         //        && !MyfacesConfig.getCurrentInstance(
         //            ctx.getFacesContext().getExternalContext()).isRefreshTransientBuildOnPSSPreserveState())
         
         // If we save the value each time the view is updated, we can use PSS on the dynamic parts,
         // just calling markInitialState() on the required components, simplifying the algorithm.
         if (fcc.isUsingPSSOnThisView() && !fcc.isRefreshTransientBuildOnPSSPreserveState())
         {
             UIViewRoot root = getViewRoot(ctx, parent);
             FaceletState map = (FaceletState) root.getAttributes().get(FACELET_STATE_INSTANCE);
             if (map == null)
             {
                 map = new FaceletState();
                 root.getAttributes().put(FACELET_STATE_INSTANCE, map);
             }
             map.putState(uniqueId, value);
         }
     }
 
 }