/* FormatedDateConverter.java

	Purpose:
		
	Description:
		
	History:
		Jun 22, 2011 11:22:20 AM, Created by henrichen

Copyright (C) 2011 Potix Corporation. All Rights Reserved.
*/
package org.zkoss.bind.converter;

import java.io.Serializable;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;

import org.zkoss.bind.BindContext;
import org.zkoss.bind.Converter;
import org.zkoss.bind.sys.Binding;
import org.zkoss.util.Locales;
import org.zkoss.util.TimeZones;
import org.zkoss.zk.ui.Component;
import org.zkoss.zk.ui.UiException;

/**
 * Converter to convert String to Date.
 * @author henrichen
 * @since 6.0.0
 */
public class FormatedDateConverter implements Converter, Serializable {

	private static final long serialVersionUID = 1463169907348730644L;

	/**
	 * Convert Date to String.
	 * @param val date to be converted
	 * @param comp associated component
	 * @param ctx bind context for associate {@link Binding} and extra parameter (e.g. format)
	 * @return the converted String
	 */
	public Object coerceToUi(Object val, Component comp, BindContext ctx) {
		//user sets format in annotation of binding or args when calling binder.addPropertyBinding()  
		final String format = (String) ctx.getConverterArg("format");
		if (format == null)
			throw new NullPointerException("format attribute not found");
		final Date date = (Date) val;
		return date == null ? null : getLocalizedSimpleDateFormat(format).format(date);
	}

	/**
	 * Convert String to Date.
	 * @param val date in string form
	 * @param comp associated component
	 * @param ctx bind context for associate {@link Binding} and extra parameter (e.g. format)
	 * @return the converted Date
	 */
	public Object coerceToBean(Object val, Component comp, BindContext ctx) {
		final String format = (String) ctx.getConverterArg("format");
		if (format == null)
			throw new NullPointerException("format attribute not found");
		final String date = (String) val;
		try {
			return date == null ? null : getLocalizedSimpleDateFormat(format).parse(date);
		} catch (ParseException e) {
			throw UiException.Aide.wrap(e);
		}
	}

	private static SimpleDateFormat getLocalizedSimpleDateFormat(String formatPtn) {
		SimpleDateFormat sdf = new SimpleDateFormat(formatPtn, Locales.getCurrent());
		sdf.setTimeZone(TimeZones.getCurrent());
		return sdf;
	}
}