/*
    * 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 javax.faces.convert;
  
  import java.text.DateFormat;
  import java.text.ParseException;
  import java.text.SimpleDateFormat;
  import java.util.Date;
  import java.util.Locale;
  import java.util.TimeZone;
  
  import javax.faces.component.PartialStateHolder;
  import javax.faces.component.UIComponent;
  import javax.faces.context.FacesContext;
  
  import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFConverter;
  import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFJspProperty;
  import org.apache.myfaces.buildtools.maven2.plugin.builder.annotation.JSFProperty;
  
  /**
   * This tag associates a date time converter with the nearest parent UIComponent.
   * 
   * Unless otherwise specified, all attributes accept static values or EL expressions.
   * 
   * see Javadoc of <a href="http://java.sun.com/javaee/javaserverfaces/1.2/docs/api/index.html">JSF Specification</a>
   *
   * @author Thomas Spiegl (latest modification by $Author: bommel $)
   * @version $Revision: 1187700 $ $Date: 2011-10-22 07:19:37 -0500 (Sat, 22 Oct 2011) $
   */
  @JSFConverter(
      name="f:convertDateTime",
      bodyContent="empty",
      tagClass="org.apache.myfaces.taglib.core.ConvertDateTimeTag")
  @JSFJspProperty(
      name="binding", 
      returnType = "javax.faces.convert.DateTimeConverter",
      longDesc = "A ValueExpression that evaluates to a DateTimeConverter.")
  public class DateTimeConverter
          implements Converter, PartialStateHolder
  {
  
      // API field
      public static final String CONVERTER_ID = "javax.faces.DateTime";
      public static final String DATE_ID = "javax.faces.converter.DateTimeConverter.DATE";
      public static final String DATETIME_ID = "javax.faces.converter.DateTimeConverter.DATETIME";
      public static final String STRING_ID = "javax.faces.converter.STRING";
      public static final String TIME_ID = "javax.faces.converter.DateTimeConverter.TIME";
  
      // internal constants
      private static final String TYPE_DATE = "date";
      private static final String TYPE_TIME = "time";
      private static final String TYPE_BOTH = "both";
      private static final String STYLE_DEFAULT = "default";
      private static final String STYLE_MEDIUM = "medium";
      private static final String STYLE_SHORT = "short";
      private static final String STYLE_LONG = "long";
      private static final String STYLE_FULL = "full";
      private static final TimeZone TIMEZONE_DEFAULT = TimeZone.getTimeZone("GMT");
  
      private String _dateStyle;
      private Locale _locale;
      private String _pattern;
      private String _timeStyle;
      private TimeZone _timeZone;
      private String _type;
      private boolean _transient;
  
      // CONSTRUCTORS
      public DateTimeConverter()
      {
      }
  
      // METHODS
      public Object getAsObject(FacesContext facesContext, UIComponent uiComponent, String value)
      {
          if (facesContext == null) throw new NullPointerException("facesContext");
          if (uiComponent == null) throw new NullPointerException("uiComponent");
  
          if (value != null)
          {
              value = value.trim();
              if (value.length() > 0)
              {
                 DateFormat format = getDateFormat();
                 TimeZone tz = getTimeZone();
                 if( tz != null )
                     format.setTimeZone( tz );
                 try
                 {
                     return format.parse(value);
                 }
                 catch (ParseException e)
                 {
                     String type = getType();
                     Object[] args = new Object[]{value,format.format(new Date()),_MessageUtils.getLabel(facesContext, uiComponent)};
                     
                     if(type.equals(TYPE_DATE))
                         throw new ConverterException(_MessageUtils.getErrorMessage(facesContext,DATE_ID,args));
                     else if (type.equals(TYPE_TIME))
                         throw new ConverterException(_MessageUtils.getErrorMessage(facesContext,TIME_ID,args));
                     else if (type.equals(TYPE_BOTH))
                         throw new ConverterException(_MessageUtils.getErrorMessage(facesContext,DATETIME_ID,args));
                     else
                         throw new ConverterException("invalid type '" + _type + "'");
                 }
             }
         }
         return null;
     }
 
     public String getAsString(FacesContext facesContext, UIComponent uiComponent, Object value)
     {
         if (facesContext == null) throw new NullPointerException("facesContext");
         if (uiComponent == null) throw new NullPointerException("uiComponent");
 
         if (value == null)
         {
             return "";
         }
         if (value instanceof String)
         {
             return (String)value;
         }
 
         DateFormat format = getDateFormat();
         TimeZone tz = getTimeZone(); 
         if (tz != null)
         {
             format.setTimeZone(tz);
         }
         try
         {
             return format.format(value);
         }
         catch (Exception e)
         {
             throw new ConverterException(_MessageUtils.getErrorMessage(facesContext, STRING_ID, new Object[]{value,_MessageUtils.getLabel(facesContext, uiComponent)}),e);
         }
     }
 
     private DateFormat getDateFormat()
     {
         String type = getType();
         DateFormat format;
         if (_pattern != null)
         {
             try 
             {
                 format = new SimpleDateFormat(_pattern, getLocale());
             } 
                 catch (IllegalArgumentException iae)
             {
                 throw new ConverterException("Invalid pattern", iae);    
             }
         }
         else if (type.equals(TYPE_DATE))
         {
             format = DateFormat.getDateInstance(calcStyle(getDateStyle()), getLocale());
         }
         else if (type.equals(TYPE_TIME))
         {
             format = DateFormat.getTimeInstance(calcStyle(getTimeStyle()), getLocale());
         }
         else if (type.equals(TYPE_BOTH))
         {
             format = DateFormat.getDateTimeInstance(calcStyle(getDateStyle()),
                                                     calcStyle(getTimeStyle()),
                                                     getLocale());
         }
         else
         {
             throw new ConverterException("invalid type '" + _type + "'");
         }
         
         // format cannot be lenient (JSR-127)
         format.setLenient(false);
         return format;
     }
 
     private int calcStyle(String name)
     {
         if (name.equals(STYLE_DEFAULT))
         {
             return DateFormat.DEFAULT;
         }
         if (name.equals(STYLE_MEDIUM))
         {
             return DateFormat.MEDIUM;
         }
         if (name.equals(STYLE_SHORT))
         {
             return DateFormat.SHORT;
         }
         if (name.equals(STYLE_LONG))
         {
             return DateFormat.LONG;
         }
         if (name.equals(STYLE_FULL))
         {
             return DateFormat.FULL;
         }
 
         throw new ConverterException("invalid style '" + name + "'");
     }
 
     // STATE SAVE/RESTORE
     public void restoreState(FacesContext facesContext, Object state)
     {
         if (state != null)
         {
             Object[] values = (Object[])state;
             _dateStyle = (String)values[0];
             _locale = (Locale)values[1];
             _pattern = (String)values[2];
             _timeStyle = (String)values[3];
             _timeZone = (TimeZone)values[4];
             _type = (String)values[5];
         }
     }
 
     public Object saveState(FacesContext facesContext)
     {
         if (!initialStateMarked())
         {
             Object[] values = new Object[6];
             values[0] = _dateStyle;
             values[1] = _locale;
             values[2] = _pattern;
             values[3] = _timeStyle;
             values[4] = _timeZone;
             values[5] = _type;
             return values;
         }
         return null;
     }
 
     // GETTER & SETTER
     
     /**
      * The style of the date.  Values include: default, short, medium, 
      * long, and full.
      * 
      */
     @JSFProperty
     public String getDateStyle()
     {
         return _dateStyle != null ? _dateStyle : STYLE_DEFAULT;
     }
 
     public void setDateStyle(String dateStyle)
     {
         //TODO: validate timeStyle
         _dateStyle = dateStyle;
         clearInitialState();
     }
 
     /**
      * The name of the locale to be used, instead of the default.
      * 
      */
     @JSFProperty
     public Locale getLocale()
     {
         if (_locale != null) return _locale;
         FacesContext context = FacesContext.getCurrentInstance();
         return context.getViewRoot().getLocale();
     }
 
     public void setLocale(Locale locale)
     {
         _locale = locale;
         clearInitialState();
     }
 
     /**
      * A custom Date formatting pattern, in the format used by java.text.SimpleDateFormat.
      * 
      */
     @JSFProperty
     public String getPattern()
     {
         return _pattern;
     }
 
     public void setPattern(String pattern)
     {
         _pattern = pattern;
         clearInitialState();
     }
 
     /**
      * The style of the time.  Values include:  default, short, medium, long, 
      * and full.
      * 
      */
     @JSFProperty
     public String getTimeStyle()
     {
         return _timeStyle != null ? _timeStyle : STYLE_DEFAULT;
     }
 
     public void setTimeStyle(String timeStyle)
     {
         //TODO: validate timeStyle
         _timeStyle = timeStyle;
         clearInitialState();
     }
 
     /**
      * The time zone to use instead of GMT (the default timezone). When
      * this value is a value-binding to a TimeZone instance, that
      * timezone is used. Otherwise this value is treated as a String
      * containing a timezone id, ie as the ID parameter of method
      * java.util.TimeZone.getTimeZone(String).
      * 
      */
     @JSFProperty
     public TimeZone getTimeZone()
     {
         return _timeZone != null ? _timeZone : TIMEZONE_DEFAULT;
     }
 
     public void setTimeZone(TimeZone timeZone)
     {
         _timeZone = timeZone;
         clearInitialState();
     }
 
     public boolean isTransient()
     {
         return _transient;
     }
 
     public void setTransient(boolean aTransient)
     {
         _transient = aTransient;
     }
 
     /**
      * Specifies whether the date, time, or both should be 
      * parsed/formatted.  Values include:  date, time, and both.
      * Default based on setting of timeStyle and dateStyle.
      * 
      */
     @JSFProperty
     public String getType()
     {
         return _type != null ? _type : TYPE_DATE;
     }
 
     public void setType(String type)
     {
         //TODO: validate type
         _type = type;
         clearInitialState();
     }
     
     private boolean _initialStateMarked = false;
 
     public void clearInitialState()
     {
         _initialStateMarked = false;
     }
 
     public boolean initialStateMarked()
     {
         return _initialStateMarked;
     }
 
     public void markInitialState()
     {
         _initialStateMarked = true;
     }
 }