/*
    * 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.orchestra.dynaForm.jsf.guiBuilder;
  
  import org.apache.myfaces.orchestra.dynaForm.jsf.component.DynaForm;
  import org.apache.myfaces.orchestra.dynaForm.metadata.MetaData;
  import org.apache.myfaces.orchestra.dynaForm.metadata.MetaField;
  import org.apache.myfaces.orchestra.frameworkAdapter.FrameworkAdapter;
  
  import java.util.Iterator;
  import java.util.Map;
  
  import javax.faces.context.FacesContext;
  import javax.faces.el.ValueBinding;
  
  /**
   * The slipstream will bring the configuration-metaData/gui together
   */
  public class Slipstream
  {
      private MetaData modelMetaData;
      private GuiBuilder guiBuilder;
      private Map<String, String> labelBundle;
      private DynaForm dynaForm;
  
      public Slipstream()
      {
      }
  
      public MetaData getModelMetaData()
      {
          return modelMetaData;
      }
  
      public void setModelMetaData(MetaData modelMetaData)
      {
          this.modelMetaData = modelMetaData;
      }
  
      public GuiBuilder getGuiBuilder()
      {
          return guiBuilder;
      }
  
      public void setGuiBuilder(GuiBuilder guiBuilder)
      {
          this.guiBuilder = guiBuilder;
      }
  
      public Map<String, String> getLabelBundle()
      {
          return labelBundle;
      }
  
      public void setLabelBundle(Map<String, String> labelBundle)
      {
          this.labelBundle = labelBundle;
      }
  
      public DynaForm getDynaForm()
      {
          return dynaForm;
      }
  
      public void setDynaForm(DynaForm dynaForm)
      {
          this.dynaForm = dynaForm;
      }
  
      public void process()
      {
          configureGuiBuilder();
  
          MetaData metaData = modelMetaData;
          Iterator<String> iterFieldNames = metaData.iterFieldNames();
          while (iterFieldNames.hasNext())
          {
              String fieldName = iterFieldNames.next();
              MetaField field = modelMetaData.getField(fieldName);
              Object ch = field.getComponentHandler();
              if (ch == null)
              {
                  // No component-handler; let the guiBuilder decide what JSF component to create
                 // for this field.
                 guiBuilder.buildField(field);
             }
             else
             {
                 getComponentHandler(ch).buildComponent(dynaForm, guiBuilder, field);
             }
         }
     }
 
     protected DynaFormComponentHandler getComponentHandler(Object ch)
     {
         if (ch instanceof ValueBinding)
         {
             FacesContext facesContext = FacesContext.getCurrentInstance();
             ValueBinding vb = (ValueBinding) ch;
             ch = vb.getValue(facesContext);
             
             if (ch == null)
             {
                 throw new IllegalArgumentException(
                         "ComponentHandler expression '" + vb.getExpressionString() + "' returned null.");
             }
         }
 
         if (ch instanceof DynaFormComponentHandler)
         {
             return (DynaFormComponentHandler) ch;
         }
 
         if (ch instanceof String)
         {
             String chName = (String) ch;
             Object bean = FrameworkAdapter.getCurrentInstance().getBean(chName);
             if (bean == null)
             {
                 throw new IllegalArgumentException(
                     "No component handler with bean name [" + chName + "] found.");
             }
             if (!(bean instanceof DynaFormComponentHandler))
             {
                 throw new IllegalArgumentException(
                     "Managed bean with name [" + chName + 
                     "] doesn't implement interface " + DynaFormComponentHandler.class.getName());
             }
             
             return (DynaFormComponentHandler) bean;
         }
 
         throw new IllegalArgumentException(
                 "Invalid ComponentHandler of type '" +
                 ch.getClass() +
                 "' found; String or DynaFormComponentHandler expected.");
     }
 
     protected void configureGuiBuilder()
     {
         guiBuilder.setFormDisplayOnly(dynaForm.isDisplayOnly());
         guiBuilder.setLabelBundle(getLabelBundle());
         guiBuilder.setIdAsDisplayOnly(dynaForm.isIdAsDisplayOnly());
     }
 }