/*
    * Copyright 1999-2004 The Apache Software Foundation.
    * 
    * Licensed 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.struts.flow.sugar;
  
  import org.mozilla.javascript.NativeJavaObject;
  import org.mozilla.javascript.Scriptable;
  import org.mozilla.javascript.Wrapper;
  import org.apache.commons.beanutils.DynaBean;
  import org.apache.commons.beanutils.DynaProperty;
  
  import java.io.Serializable;
  
  import java.util.Map;
  
  /***
   * Wrap a DynaBean for JavaScript.  Currently only supports named,
   * and not mapped or indexed properties for Javascript shortcuts.  
   * Mapped and indexed properties are still available through their 
   * get() methods.  
   */
  public class ScriptableDynaBean extends JavaObjectWrapper implements Scriptable, Wrapper, Serializable {
  
      private DynaBean bean;
  
      public ScriptableDynaBean() {
          super();
      }
  
      public ScriptableDynaBean(DynaBean bean) {
          this.bean = bean;
      }
      
      public ScriptableDynaBean(Scriptable scope, Object javaObject, Class staticType, Map functions) {
          super(scope, javaObject, staticType, functions);
          if (javaObject instanceof DynaBean) {
              this.bean = (DynaBean)javaObject;
          } else {
              throw new IllegalArgumentException("Passed object "+javaObject+" is not an instance of DynaBean");
          }
      }
  
      public String getClassName() {
          return "DynaBean";
      }
  
      public boolean has(String name, Scriptable start) {
          return (super.has(name, start) || has(name));
      }
  
      /***
       * no numeric properties
       */
      public boolean has(int index, Scriptable start) {
          return false;
      }
  
      public Object get(String name, Scriptable start) {
          if (super.has(name, start)) {
              return super.get(name, start);
          } else if (has(name)) {
              return wrap(this.bean.get(name), start);
          } else {
              return Scriptable.NOT_FOUND;
          }
      }
      
      private boolean has(String name) {
          try {
              Object val = this.bean.get(name);
              return (val != null);
          } catch (IllegalArgumentException ex) {
              // Do nothing as we don't care if it complains
          }
          return false;
      }
  
      public Object get(int index, Scriptable start) {
          return NOT_FOUND;
      }
  
      public void put(String name, Scriptable start, Object value) {
          if (value instanceof NativeJavaObject) {
              value = ((NativeJavaObject)value).unwrap();
          }
          bean.set(name, value);
      }
 
     public void put(int index, Scriptable start, Object value) {
     }
 
     public void delete(String id) {
         bean.set(id, null);
     }
 
     public void delete(int index) {
     }
 
     public Scriptable getPrototype() {
         return prototype;
     }
 
     public void setPrototype(Scriptable prototype) {
         this.prototype = prototype;
     }
 
     public Scriptable getParentScope() {
         return parent;
     }
 
     public void setParentScope(Scriptable parent) {
         this.parent = parent;
     }
 
     /***
      *  The id array that is returned is of class DynaProperties,
      *  rather than the perhaps expected String.
      */
     public Object[] getIds() {
         DynaProperty[] props = this.bean.getDynaClass().getDynaProperties();
         String[] ids = new String[props.length];
         for (int x=0; x < props.length; x++) {
             ids[x] = props[x].getName();
         }
         return ids;
     }
 
     public Object getDefaultValue(Class typeHint) {
         return this.bean.toString();
     }
 
     public boolean hasInstance(Scriptable value) {
         Scriptable proto = value.getPrototype();
         while (proto != null) {
             if (proto.equals(this)) 
                 return true;
             proto = proto.getPrototype();
         }
 
         return false;
     }
 
     /***
      * Return the DynaBean that is wrapped by this class.
      */
     public Object unwrap() {
         return this.bean;
     }
 
 }