/*
    * 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.commons.validator;
  
  import java.io.Serializable;
  import java.util.ArrayList;
  import java.util.HashMap;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Locale;
  import java.util.Map;
  
  import javax.el.ValueExpression;
  import javax.faces.application.FacesMessage;
  import javax.faces.component.StateHolder;
  import javax.faces.context.FacesContext;
  import javax.faces.validator.Validator;
  
  import org.apache.myfaces.commons.util.MessageUtils;
  
  /**
   * Base validator implementation for Apache MyFaces Commons Validators.
   *
   * @JSFValidator
   *   configExcluded = "true"
   *   tagClass = "org.apache.myfaces.commons.validator.ValidatorBaseTag"
   */
  public abstract class ValidatorBase implements StateHolder, Validator {
  
      private String _summaryMessage = null;
      private String _detailMessage = null;
      private boolean _transient = false;
  
      /**
       * alternate validation error summary message format string
       * 
       * @JSFProperty
       * @return  The summary message to be displayed
       */
      public String getSummaryMessage()
      {
          if (_summaryMessage != null) return _summaryMessage;
          ValueExpression expression = getValueExpression("summaryMessage");
          return expression != null ? getStringValue(getFacesContext(), expression) : null;
      }
  
      /**
       *
       * @param message   The summary message to be displayed.
       */
      public void setSummaryMessage(String message) {
          _summaryMessage = message;
      }
  
      /**
       * alternate validation error detail message format string 
       * (use 'message' and 'detailMessage' alternatively)
       * 
       * @JSFProperty
       * @return  The message.
       * @deprecated Use getDetailMessage()
       */
      public String getMessage() {
          return getDetailMessage();
      }
  
      /**
       *
       * @param message  The detail message to be displayed.
       * @deprecated Use setDetailMessage()
       */
      public void setMessage(String message) {
          setDetailMessage(message);
      }
  
  
      /**
       * alternate validation error detail message format string 
       * (use 'message' and 'detailMessage' alternatively)
       *
       * @JSFProperty
       * @return  The detail message.
       */
     public String getDetailMessage() {
         if (_detailMessage != null) return _detailMessage;
         ValueExpression vb = getValueExpression("detailMessage");
         return vb != null ? getStringValue(getFacesContext(), vb) : null;
     }
 
     /**
      *
      * @param message  The detail message to be displayed.
      */
     public void setDetailMessage(String message) {
         _detailMessage = message;
     }
 
 
     /**
      * @param context
      */
     public Object saveState(FacesContext context) {
         Object[] state = new Object[3];
         state[0] = _summaryMessage;
         state[1] = _detailMessage;
         state[2] = saveValueExpressionMap(context);
         return state;
     }
 
     public void restoreState(FacesContext context, Object state) {
         Object[] values = (Object[]) state;
         _summaryMessage = (String) values[0];
         _detailMessage = (String) values[1];
         restoreValueExpressionMap(context, values[2]);
     }
 
     public boolean isTransient() {
         return _transient;
     }
 
     public void setTransient(boolean newTransientValue) {
         _transient = newTransientValue;
     }
 
     // Utility methods
 
     /**
      * @param defaultMessage The default message we would expect.
      * @param args Arguments for parsing this message.
      * @return FacesMessage
      */
     protected FacesMessage getFacesMessage(String defaultMessage, Object[] args) {
         FacesMessage msg;
 
         if (getSummaryMessage() == null && getDetailMessage() == null)
         {
             msg = MessageUtils.getMessage(FacesMessage.SEVERITY_ERROR, defaultMessage, args);
         } else {
             Locale locale = MessageUtils.getCurrentLocale();
             String summaryText = MessageUtils.substituteParams(locale, getSummaryMessage(), args);
             String detailText = MessageUtils.substituteParams(locale, getDetailMessage(), args);
             msg = new FacesMessage(FacesMessage.SEVERITY_ERROR, summaryText, detailText);
         }
         return msg;
     }
 
     // --------------------- borrowed from UIComponentBase ------------
 
     private Map _valueExpressionMap = null;
 
     public ValueExpression getValueExpression(String name)
     {
         if (name == null) throw new NullPointerException("name");
         if (_valueExpressionMap == null)
         {
             return null;
         }
         else
         {
             return (ValueExpression)_valueExpressionMap.get(name);
         }
     }
 
     public void setValueExpression(String name,
                                 ValueExpression binding)
     {
         if (name == null) throw new NullPointerException("name");
         if (_valueExpressionMap == null)
         {
             _valueExpressionMap = new HashMap();
         }
         _valueExpressionMap.put(name, binding);
     }
 
     private Object saveValueExpressionMap(FacesContext context)
     {
         if (_valueExpressionMap != null)
         {
             int initCapacity = (_valueExpressionMap.size() * 4 + 3) / 3;
             HashMap stateMap = new HashMap(initCapacity);
             for (Iterator it = _valueExpressionMap.entrySet().iterator(); it.hasNext(); )
             {
                 Map.Entry entry = (Map.Entry)it.next();
                 stateMap.put(entry.getKey(),
                              saveAttachedState(context, entry.getValue()));
             }
             return stateMap;
         }
         else
         {
             return null;
         }
     }
 
     private void restoreValueExpressionMap(FacesContext context, Object stateObj)
     {
         if (stateObj != null)
         {
             Map stateMap = (Map)stateObj;
             int initCapacity = (stateMap.size() * 4 + 3) / 3;
             _valueExpressionMap = new HashMap(initCapacity);
             for (Iterator it = stateMap.entrySet().iterator(); it.hasNext(); )
             {
                 Map.Entry entry = (Map.Entry)it.next();
                 _valueExpressionMap.put(entry.getKey(),
                                      restoreAttachedState(context, entry.getValue()));
             }
         }
         else
         {
             _valueExpressionMap = null;
         }
     }
 
     /**
      * Serializes objects which are "attached" to this component but which are
      * not UIComponent children of it. Examples are validator and listener
      * objects. To be precise, it returns an object which implements
      * java.io.Serializable, and which when serialized will persist the
      * state of the provided object.
      * <p>
      * If the attachedObject is a List then every object in the list is saved
      * via a call to this method, and the returned wrapper object contains
      * a List object.
      * <p>
      * If the object implements StateHolder then the object's saveState is
      * called immediately, and a wrapper is returned which contains both
      * this saved state and the original class name. However in the case
      * where the StateHolder.isTransient method returns true, null is
      * returned instead.
      * <p>
      * If the object implements java.io.Serializable then the object is simply
      * returned immediately; standard java serialization will later be used
      * to store this object.
      * <p>
      * In all other cases, a wrapper is returned which simply stores the type
      * of the provided object. When deserialized, a default instance of that
      * type will be recreated.
      */
     public static Object saveAttachedState(FacesContext context,
                                            Object attachedObject)
     {
         if (attachedObject == null) return null;
         if (attachedObject instanceof List)
         {
             List lst = new ArrayList(((List)attachedObject).size());
             for (Iterator it = ((List)attachedObject).iterator(); it.hasNext(); )
             {
                 lst.add(saveAttachedState(context, it.next()));
             }
             return new _AttachedListStateWrapper(lst);
         }
         else if (attachedObject instanceof StateHolder)
         {
             if (((StateHolder)attachedObject).isTransient())
             {
                 return null;
             }
             else
             {
                 return new _AttachedStateWrapper(attachedObject.getClass(),
                                                  ((StateHolder)attachedObject).saveState(context));
             }
         }
         else if (attachedObject instanceof Serializable)
         {
             return attachedObject;
         }
         else
         {
             return new _AttachedStateWrapper(attachedObject.getClass(), null);
         }
     }
 
     public static Object restoreAttachedState(FacesContext context,
                                               Object stateObj)
             throws IllegalStateException
     {
         if (context == null) throw new NullPointerException("context");
         if (stateObj == null) return null;
         if (stateObj instanceof _AttachedListStateWrapper)
         {
             List lst = ((_AttachedListStateWrapper)stateObj).getWrappedStateList();
             List restoredList = new ArrayList(lst.size());
             for (Iterator it = lst.iterator(); it.hasNext(); )
             {
                 restoredList.add(restoreAttachedState(context, it.next()));
             }
             return restoredList;
         }
         else if (stateObj instanceof _AttachedStateWrapper)
         {
             Class clazz = ((_AttachedStateWrapper)stateObj).getClazz();
             Object restoredObject;
             try
             {
                 restoredObject = clazz.newInstance();
             }
             catch (InstantiationException e)
             {
                 throw new RuntimeException("Could not restore StateHolder of type " + clazz.getName() + " (missing no-args constructor?)", e);
             }
             catch (IllegalAccessException e)
             {
                 throw new RuntimeException(e);
             }
             if (restoredObject instanceof StateHolder)
             {
                 Object wrappedState = ((_AttachedStateWrapper)stateObj).getWrappedStateObject();
                 ((StateHolder)restoredObject).restoreState(context, wrappedState);
             }
             return restoredObject;
         }
         else
         {
             return stateObj;
         }
     }
 
 
     protected FacesContext getFacesContext()
     {
         return FacesContext.getCurrentInstance();
     }
     protected String getStringValue(FacesContext context, ValueExpression vb)
     {
         Object value = vb.getValue(context.getELContext());
         if (value != null)
         {
             return value.toString();
         }
         return null;
     }
 }