/*
    * 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.compiler;
  
  import java.io.IOException;
  import java.io.Writer;
  
  import javax.el.ELException;
  import javax.faces.FacesException;
  import javax.faces.component.UIComponent;
  import javax.faces.component.UniqueIdVendor;
  import javax.faces.view.facelets.FaceletContext;
  import javax.faces.view.facelets.FaceletException;
  
  import org.apache.myfaces.view.facelets.FaceletCompositionContext;
  import org.apache.myfaces.view.facelets.el.ELText;
  import org.apache.myfaces.view.facelets.tag.jsf.ComponentSupport;
  import org.apache.myfaces.view.facelets.util.FastWriter;
  
  /**
   * @author Adam Winer
   * @version $Id$
   */
  final class UIInstructionHandler extends AbstractUIHandler
  {
  
      private final String alias;
  
      private final String id;
  
      private final ELText txt;
  
      private final Instruction[] instructions;
  
      private final int length;
  
      private final boolean literal;
  
      public UIInstructionHandler(String alias, String id, Instruction[] instructions, ELText txt)
      {
          this.alias = alias;
          this.id = id;
          this.instructions = instructions;
          this.txt = txt;
          this.length = txt.toString().length();
  
          boolean literal = true;
          int size = instructions.length;
  
          for (int i = 0; i < size; i++)
          {
              Instruction ins = this.instructions[i];
              if (!ins.isLiteral())
              {
                  literal = false;
                  break;
              }
          }
  
          this.literal = literal;
      }
  
      public void apply(FaceletContext ctx, UIComponent parent) throws IOException, FacesException, FaceletException,
              ELException
      {
          if (parent != null)
          {
              String facetName = this.getFacetName(ctx, parent);
              
              // our id
              String id = ctx.generateUniqueId(this.id);
  
              // grab our component
              UIComponent c = null;
              FaceletCompositionContext mctx= FaceletCompositionContext.getCurrentInstance(ctx);
              
              if (mctx.isRefreshingSection())
              {
                  if (facetName != null)
                  {
                      c = ComponentSupport.findChildInFacetByTagId(parent, id, facetName);
                  }
                  else
                 {
                     c = ComponentSupport.findChildInChildrenByTagId(parent, id);
                 }
             }
             boolean componentFound = false;
             if (c != null)
             {
                 componentFound = true;
 
                 mctx.incrementUniqueComponentId();
                 // mark all children for cleaning
                 mctx.markForDeletion(c);
             }
             else
             {
                 Instruction[] applied;
                 String componentId = mctx.generateUniqueComponentId();
                 if (this.literal)
                 {
                     applied = this.instructions;
                 }
                 else
                 {
                     int size = this.instructions.length;
                     applied = new Instruction[size];
                     // Create a new list with all of the necessary applied
                     // instructions
                     Instruction ins;
                     for (int i = 0; i < size; i++)
                     {
                         ins = this.instructions[i];
                         applied[i] = ins.apply(ctx.getExpressionFactory(), ctx);
                     }
                 }
 
                 c = new UIInstructions(txt, applied);
                 // mark it owned by a facelet instance
                 //c.setId(ComponentSupport.getViewRoot(ctx, parent).createUniqueId());
 
                 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(). Also, note that UIViewRoot.createUniqueId() javadoc
                     // says we could send as seed the facelet generated id.
                     String uid = uniqueIdVendor.createUniqueId(ctx.getFacesContext(), componentId);
                     c.setId(uid);
                 }                
                 //c.getAttributes().put(ComponentSupport.MARK_CREATED, id);
                 ((UIInstructions)c).setMarkCreated(id);
             }
             
             boolean oldProcessingEvents = ctx.getFacesContext().isProcessingEvents();
             // finish cleaning up orphaned children
             if (componentFound)
             {
                 mctx.finalizeForDeletion(c);
                 if (mctx.isRefreshingSection())
                 {
                     ctx.getFacesContext().setProcessingEvents(false); 
                 }
                 if (facetName == null)
                 {
                     parent.getChildren().remove(c);
                 }
                 else
                 {
                     ComponentSupport.removeFacet(ctx, parent, c, facetName);
                 }
                 if (mctx.isRefreshingSection())
                 {
                     ctx.getFacesContext().setProcessingEvents(oldProcessingEvents);
                 }
             }
             if (componentFound && mctx.isRefreshingSection())
             {
                 ctx.getFacesContext().setProcessingEvents(false); 
             }
             if (facetName == null)
             {
                 parent.getChildren().add(c);
             }
             else
             {
                 ComponentSupport.addFacet(ctx, parent, c, facetName);
             }
             if (componentFound && mctx.isRefreshingSection())
             {
                 ctx.getFacesContext().setProcessingEvents(oldProcessingEvents);
             }
         }
     }
 
     public String toString()
     {
         return this.txt.toString();
     }
 
     public String getText()
     {
         return this.txt.toString();
     }
 
     public String getText(FaceletContext ctx)
     {
         Writer writer = new FastWriter(this.length);
         try
         {
             this.txt.apply(ctx.getExpressionFactory(), ctx).write(writer, ctx);
         }
         catch (IOException e)
         {
             throw new ELException(this.alias + ": " + e.getMessage(), e.getCause());
         }
         return writer.toString();
     }
 
 }