package org.andromda.cartridges.jsf.converters;
   
   import java.text.DateFormat;
   import java.text.SimpleDateFormat;
   import java.util.Calendar;
   import java.util.Date;
   import java.util.TimeZone;
   import javax.faces.component.UIComponent;
   import javax.faces.context.FacesContext;
  import javax.faces.convert.ConverterException;
  import javax.faces.el.ValueBinding;
  import org.apache.myfaces.custom.calendar.HtmlCalendarRenderer.DateConverter;
  
  /**
   * Overrides the default DateTimeConverter to include conversion of Calendar
   * instances as well as Date instances.
   *
   * <p>
   * Unfortunately because of poor design in myfaces's calendar component, we have to implement
   * DateConverter so that we can correctly convert to a date in the inputCalendar implementation.
   * </p>
   *
   * @author Chad Brandon
   */
  public class JSFDateTimeConverter
      extends javax.faces.convert.DateTimeConverter
      implements DateConverter
  {
      /**
       * @see javax.faces.convert.DateTimeConverter#getAsString(javax.faces.context.FacesContext, javax.faces.component.UIComponent, java.lang.Object)
       * @throws ConverterException
       */
      @Override
      public String getAsString(
          FacesContext context,
          UIComponent component,
          Object value)
      {
          if (value instanceof Calendar)
          {
              // - if the time zone is not explicitly set, use the one from the calendar
              if (!this.timeZoneIsSet)
              {
                  // - use the time zone from the calendar
                  this.setTimeZone(((Calendar)value).getTimeZone());
              }
              value = ((Calendar)value).getTime();
          }
          final String pattern = this.getPattern();
          String result = null;
          if (value != null && pattern != null && pattern.trim().length() > 0)
          {
              DateFormat format = new SimpleDateFormat(pattern);
              format.setTimeZone(this.getTimeZone());
              result = format.format((Date)value);
          }
          return result;
      }
  
      /**
       * @see javax.faces.convert.DateTimeConverter#getAsObject(javax.faces.context.FacesContext, javax.faces.component.UIComponent, String)
       */
      @Override
      public Object getAsObject(
          FacesContext context,
          UIComponent component,
          String value)
          throws ConverterException
      {
          Object asObject = null;
          final Class componentType = this.getComponentType(
                  context,
                  component);
          if (componentType != null)
          {
              asObject = super.getAsObject(
                      context,
                      component,
                      value);
              if (Calendar.class.isAssignableFrom(componentType) && asObject instanceof Date)
              {
                  final Calendar calendar = Calendar.getInstance();
                  calendar.setTimeZone(this.getTimeZone());
                  calendar.setTime((Date)asObject);
                  asObject = calendar;
              }
          }
          return asObject;
      }
  
      /**
       * Gets the component type for the given <code>component</code>.
       * @param context the current faces context.
       * @param component the component from which to retrieve the type.
       * @return true/false
       */
      protected Class getComponentType(
          final FacesContext context,
          final UIComponent component)
     {
         Class type = null;
         final ValueBinding binding = component.getValueBinding("value");
         if (binding != null)
         {
             type = binding.getType(context);
         }
         return type;
     }
 
     /**
      * Gets the component Value for the given <code>component</code>.
      * @param context the current faces context.
      * @param component the component from which to retrieve the value.
      * @return true/false
      */
     protected Object getComponentValue(
         final FacesContext context,
         final UIComponent component)
     {
         Object value = null;
         final ValueBinding binding = component.getValueBinding("value");
         if (binding != null)
         {
             value = binding.getValue(context);
         }
         return value;
     }
 
     private TimeZone timeZone;
 
     /**
      * @see #getTimeZone()
      */
     @Override
     public void restoreState(FacesContext facesContext, Object state)
     {
         super.restoreState(facesContext, state);
         Object[] values = (Object[])state;
         this.timeZone = (TimeZone)values[4];
     }
 
     /**
      * @see #getTimeZone()
      */
     @Override
     public Object saveState(FacesContext facesContext)
     {
         Object[] values = (Object[])super.saveState(facesContext);
         values[4] = this.timeZone;
         return values;
     }
 
     /**
      * Keeps track of whether or not the time zone was explicitly set.
      */
     private boolean timeZoneIsSet;
 
     /**
      * @see #getTimeZone()
      */
     @Override
     public void setTimeZone(TimeZone timeZone)
     {
         this.timeZone = timeZone;
         this.timeZoneIsSet = true;
     }
 
     /**
      * Overridden because the default timeZone is set as GMT, whereas it should be the default
      * for the operating system.
      */
     @Override
     public TimeZone getTimeZone()
     {
         return this.timeZone == null ? TimeZone.getDefault() : this.timeZone;
     }
 
     /**
      * andromda.faces.DateTime
      */
     public static final String CONVERTER_ID = "andromda.faces.DateTime";
 
     /**
      * @see org.apache.myfaces.custom.calendar.HtmlCalendarRenderer.DateConverter
      * #getAsDate(javax.faces.context.FacesContext, javax.faces.component.UIComponent)
      */
     @Override
     public Date getAsDate(
         FacesContext context,
         UIComponent component)
     {
         Object value = this.getComponentValue(
                 context,
                 component);
         if (value instanceof Calendar)
         {
             value = ((Calendar)value).getTime();
         }
         return (Date)value;
     }
 }