/*
    *  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.trinidad.webapp;
  
  import java.text.DateFormat;
  import java.text.ParseException;
  import java.text.SimpleDateFormat;
  
  import java.util.ArrayList;
  import java.util.Calendar;
  import java.util.Date;
  import java.util.HashSet;
  import java.util.List;
  import java.util.Set;
  import java.util.TimeZone;
  
  import javax.el.MethodExpression;
  import javax.el.ValueExpression;
  
  import javax.faces.component.UIComponent;
  import javax.faces.component.UIViewRoot;
  import javax.faces.context.ExternalContext;
  import javax.faces.context.FacesContext;
  import javax.faces.webapp.UIComponentELTag;
  
  import javax.servlet.jsp.JspException;
  
  import org.apache.myfaces.trinidad.bean.FacesBean;
  import org.apache.myfaces.trinidad.bean.PropertyKey;
  import org.apache.myfaces.trinidad.change.ChangeManager;
  import org.apache.myfaces.trinidad.component.UIXComponent;
  import org.apache.myfaces.trinidad.component.UIXDocument;
  import org.apache.myfaces.trinidad.context.RequestContext;
  import org.apache.myfaces.trinidad.logging.TrinidadLogger;
  
  
  /**
   * Subclass of UIComponentTag to add convenience methods,
   * and optimize where appropriate.
   */
  abstract public class UIXComponentELTag extends UIComponentELTag
  {
    public UIXComponentELTag()
    {
    }
  
    public void setAttributeChangeListener(MethodExpression attributeChangeListener)
    {
      _attributeChangeListener = attributeChangeListener;
    }
  
    @Override
    public int doStartTag() throws JspException
    {
      int retVal = super.doStartTag();
  
      //pu: There could have been some validation error during property setting
      //  on the bean, this is the closest opportunity to burst out.
      if (_validationError != null)
        throw new JspException(_validationError);
  
      return retVal;
    }
  
    @Override
    public int doEndTag() throws JspException
    {
      UIComponent component = getComponentInstance();
      
      // Apply changes once we have a stable UIComponent subtree is completely 
      //  created. End of document tag is a best bet.
      if (component instanceof UIXDocument)
      {
        if (getCreated()) 
        {
          ExternalContext ec = FacesContext.getCurrentInstance().getExternalContext();
          // Used by SessionChangeManager to confirm that the state was not restored.
          ec.getRequestMap().put(DOCUMENT_CREATED_KEY, Boolean.TRUE);
        }
        ChangeManager cm = RequestContext.getCurrentInstance().getChangeManager();
        cm.applyComponentChangesForCurrentView(FacesContext.getCurrentInstance());
      }
      return super.doEndTag();
   }
 
 
   @Override
   protected final void setProperties(UIComponent component)
   {
     if (component instanceof UIViewRoot)
     {
       throw new IllegalStateException(
          "<f:view> was not present on this page; tag " + this +
          "encountered without an <f:view> being processed.");
     }
 
     super.setProperties(component);
 
     UIXComponent uixComponent = (UIXComponent) component;
 
     if (_attributeChangeListener != null)
     {
       uixComponent.setAttributeChangeListener(_attributeChangeListener);
     }
 
     setProperties(uixComponent.getFacesBean());
   }
 
   protected void setProperty(
     FacesBean   bean,
     PropertyKey key,
     ValueExpression expression)
   {
     if (expression == null)
       return;
 
     if (expression.isLiteralText())
     {
       bean.setProperty(key, expression.getValue(null));
     }
     else
     {
       bean.setValueExpression(key, expression);
     }
   }
 
   /**
    * Set a property of type java.lang.String[].  If the value
    * is an EL expression, it will be stored as a ValueExpression.
    * Otherwise, it will parsed as a whitespace-separated series
    * of strings.
    * Null values are ignored.
    */
   protected void setStringArrayProperty(
     FacesBean       bean,
     PropertyKey     key,
     ValueExpression expression)
   {
     if (expression == null)
       return;
 
     if (expression.isLiteralText())
     {
       bean.setProperty(key, _parseNameTokens(expression.getValue(null)));
     }
     else
     {
       bean.setValueExpression(key, expression);
     }
   }
 
   /**
    * Set a property of type java.util.List<java.lang.String>.  If the value
    * is an EL expression, it will be stored as a ValueExpression.
    * Otherwise, it will parsed as a whitespace-separated series
    * of strings.
    * Null values are ignored.
    */
   protected void setStringListProperty(
     FacesBean       bean,
     PropertyKey     key,
     ValueExpression expression)
   {
     if (expression == null)
       return;
 
     if (expression.isLiteralText())
     {
       bean.setProperty(key, 
                        _parseNameTokensAsList(expression.getValue(null)));
     }
     else
     {
       bean.setValueExpression(key, expression);
     }
   }
 
   /**
    * Set a property of type java.util.Set<java.lang.String>.  If the value
    * is an EL expression, it will be stored as a ValueExpression.
    * Otherwise, it will parsed as a whitespace-separated series
    * of strings.
    * Null values are ignored.
    */
   protected void setStringSetProperty(
     FacesBean       bean,
     PropertyKey     key,
     ValueExpression expression)
   {
     if (expression == null)
       return;
 
     if (expression.isLiteralText())
     {
       bean.setProperty(key, 
                        _parseNameTokensAsSet(expression.getValue(null)));
     }
     else
     {
       bean.setValueExpression(key, expression);
     }
   }
 
   /**
    * Set a property of type java.lang.Number.  If the value
    * is an EL expression, it will be stored as a ValueBinding.
    * Otherwise, it will parsed with Integer.valueOf() or Double.valueOf() .
    * Null values are ignored.
    */
   protected void setNumberProperty(
     FacesBean   bean,
     PropertyKey key,
     ValueExpression expression)
   {
     if (expression == null)
       return;
 
     if (expression.isLiteralText())
     {
       Object value = expression.getValue(null);
       if (value != null)
       { 
         if (value instanceof Number)
         {
           bean.setProperty(key, value);
         }
         else
         {
           String valueStr = value.toString();
           if(valueStr.indexOf('.') == -1)
             bean.setProperty(key, Integer.valueOf(valueStr));
           else
             bean.setProperty(key, Double.valueOf(valueStr));
         }
       }
     }
     else
     {
       bean.setValueExpression(key, expression);
     }
   }
 
   /**
    * Set a property of type int[].  If the value
    * is an EL expression, it will be stored as a ValueExpression.
    * Otherwise, it will parsed as a whitespace-separated series
    * of ints.
    * Null values are ignored.
    */
   protected void setIntArrayProperty(
     FacesBean   bean,
     PropertyKey key,
     ValueExpression expression)
   {
     if (expression == null)
       return;
 
     if (expression.isLiteralText())
     {
       Object value = expression.getValue(null);
       if (value != null)
       {
         String[] strings = _parseNameTokens(value);
         final int[] ints;
         if (strings != null)
         {
           try
           {
             ints = new int[strings.length];
             for(int i=0; i<strings.length; i++)
             {
               int j = Integer.parseInt(strings[i]);
               ints[i] = j;
             }
           }
           catch (NumberFormatException e)
           {
             _LOG.severe("CANNOT_CONVERT_INTO_INT_ARRAY",value);
             _LOG.severe(e);
             return;
           }
         }
       }
     }
     else
     {
       bean.setValueExpression(key, expression);
     }
   }
 
   /**
    * Set a property of type java.util.Date.  If the value
    * is an EL expression, it will be stored as a ValueExpression.
    * Otherwise, it will parsed as an ISO 8601 date (yyyy-MM-dd).
    * Null values are ignored.
    */
   protected void setDateProperty(
     FacesBean   bean,
     PropertyKey key,
     ValueExpression expression)
   {
     if (expression == null)
       return;
 
     if (expression.isLiteralText())
     {
       bean.setProperty(key, _parseISODate(expression.getValue(null)));
     }
     else
     {
       bean.setValueExpression(key, expression);
     }
   }
 
     /**
    * Set a property of type java.util.Date.  If the value
    * is an EL expression, it will be stored as a ValueBinding.
    * Otherwise, it will parsed as an ISO 8601 date (yyyy-MM-dd)
    * and the time components (hour, min, second, millisecond) maximized.
    * Null values are ignored.
    */
     protected void setMaxDateProperty(
     FacesBean   bean,
     PropertyKey key,
     ValueExpression expression)
   {
     if (expression == null)
       return;
 
     if (expression.isLiteralText())
     {
       Date d = _parseISODate(expression.getValue(null));
       Calendar c = Calendar.getInstance();
       TimeZone tz = RequestContext.getCurrentInstance().getTimeZone();
       if (tz != null)
         c.setTimeZone(tz);
       c.setTime(d);
       // Original value had 00:00:00 for hours,mins, seconds now maximize those
       // to get the latest time value for the date supplied.
       c.set (Calendar.HOUR_OF_DAY, 23);
       c.set (Calendar.MINUTE, 59);
       c.set (Calendar.SECOND, 59);
       c.set (Calendar.MILLISECOND, 999);
       bean.setProperty(key, c.getTime());
     }
     else
     {
       bean.setValueExpression(key, expression);
     }
   }
 
   protected void setProperties(FacesBean bean)
   {
     // Could be abstract, but it's easier to *always* call super.setProperties(),
     // and perhaps we'll have something generic in here, esp. if we take
     // over "rendered" from UIComponentTag
   }
 
   /**
    * Sets any fatal validation error that could have happened during property
    *  setting. If this is set, tag execution aborts with a JspException at the
    *  end of doStartTag().
    * @param validationError
    */
   protected void setValidationError(String validationError)
   {
     _validationError = validationError;
   }
 
   /**
    * Parse a string into a java.util.Date object.  The
    * string must be in ISO 9601 format (yyyy-MM-dd).
    */
   static private final Date _parseISODate(Object o)
   {
     if (o == null)
       return null;
 
     String stringValue = o.toString();
     try
     {
       return _getDateFormat().parse(stringValue);
     }
     catch (ParseException pe)
     {
       _LOG.info("CANNOT_PARSE_VALUE_INTO_DATE", stringValue);
       return null;
     }
   }
 
   /**
    * Parses a whitespace separated series of name tokens.
    * @param stringValue the full string
    * @return an array of each constituent value, or null
    *  if there are no tokens (that is, the string is empty or
    *  all whitespace)
    * @todo Move to utility function somewhere (ADF Share?)
    */
   static private final String[] _parseNameTokens(Object o)
   {
     List<String> list = _parseNameTokensAsList (o);
 
     if (list == null)
       return null;
 
     return list.toArray(new String[list.size()]);
   }
 
   static private final List<String> _parseNameTokensAsList (Object o)
   {
     if (o == null)
       return null;
 
     String stringValue = o.toString();
     ArrayList<String> list = new ArrayList<String>(5);
 
     int     length = stringValue.length();
     boolean inSpace = true;
     int     start = 0;
     for (int i = 0; i < length; i++)
     {
       char ch = stringValue.charAt(i);
 
       // We're in whitespace;  if we've just departed
       // a run of non-whitespace, append a string.
       // Now, why do we use the supposedly deprecated "Character.isSpace()"
       // function instead of "isWhitespace"?  We're following XML rules
       // here for the meaning of whitespace, which specifically
       // EXCLUDES general Unicode spaces.
       if (Character.isWhitespace(ch))
       {
         if (!inSpace)
         {
           list.add(stringValue.substring(start, i));
           inSpace = true;
         }
       }
       // We're out of whitespace;  if we've just departed
       // a run of whitespace, start keeping track of this string
       else
       {
         if (inSpace)
         {
           start = i;
           inSpace = false;
         }
       }
     }
 
     if (!inSpace)
       list.add(stringValue.substring(start));
 
     if (list.isEmpty())
       return null;
 
     return list;
   }
 
   static private final Set<String> _parseNameTokensAsSet (Object o)
   {
     List<String> list = _parseNameTokensAsList(o);
 
     if (list == null)
       return null;
     else
       return new HashSet(list);
   }
 
   private static final TrinidadLogger _LOG = 
     TrinidadLogger.createTrinidadLogger(UIXComponentELTag.class);
 
   // We rely strictly on ISO 8601 formats
   private static DateFormat _getDateFormat()
   {
     SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
     TimeZone tz = RequestContext.getCurrentInstance().getTimeZone();
     if (tz != null)
       sdf.setTimeZone(tz);
     return sdf;
   }
 
   public static final String DOCUMENT_CREATED_KEY = "org.apache.myfaces.trinidad.DOCUMENTCREATED";
 
   private MethodExpression  _attributeChangeListener;
   private String            _validationError;
   
 }