package org.eclipse.osbp.vaaclipse.addons.app.converter;

import java.text.DateFormat;
import java.text.ParsePosition;
import java.util.Date;
import java.util.Locale;

import com.vaadin.data.util.converter.Converter;

@SuppressWarnings("serial")
public class VaaclipseDateConverter implements Converter<String, Date> {

	/**
	 * Returns the format used by
	 * {@link #convertToPresentation(Date, Class,Locale)} and
	 * {@link #convertToModel(String, Class, Locale)}.
	 *
	 * @param locale
	 *            The locale to use
	 * @return A DateFormat instance
	 */
	protected DateFormat getFormat(Locale locale) {
		if (locale == null) {
			locale = Locale.getDefault();
		}

		DateFormat f = DateFormat.getDateInstance(DateFormat.MEDIUM, locale);
		f.setLenient(false);
		return f;
	}

	/*
	 * (non-Javadoc)
	 *
	 * @see
	 * com.vaadin.data.util.converter.Converter#convertToModel(java.lang.Object,
	 * java.lang.Class, java.util.Locale)
	 */
	@Override
	public Date convertToModel(String value, Class<? extends Date> targetType, Locale locale)
			throws com.vaadin.data.util.converter.Converter.ConversionException {
		if (targetType != getModelType()) {
			throw new ConversionException("Converter only supports " + getModelType().getName() + " (targetType was "
					+ targetType.getName() + ")");
		}

		if (value == null) {
			return null;
		}

		// Remove leading and trailing white space
		value = value.trim();

		ParsePosition parsePosition = new ParsePosition(0);
		Date parsedValue = getFormat(locale).parse(value, parsePosition);
		if (parsePosition.getIndex() != value.length()) {
			throw new ConversionException("Could not convert '" + value + "' to " + getModelType().getName());
		}

		return parsedValue;
	}

	/*
	 * (non-Javadoc)
	 *
	 * @see
	 * com.vaadin.data.util.converter.Converter#convertToPresentation(java.lang
	 * .Object, java.lang.Class, java.util.Locale)
	 */
	@Override
	public String convertToPresentation(Date value, Class<? extends String> targetType, Locale locale)
			throws com.vaadin.data.util.converter.Converter.ConversionException {
		if (value == null) {
			return null;
		}

		return getFormat(locale).format(value);
	}

	/*
	 * (non-Javadoc)
	 *
	 * @see com.vaadin.data.util.converter.Converter#getModelType()
	 */
	@Override
	public Class<Date> getModelType() {
		return Date.class;
	}

	/*
	 * (non-Javadoc)
	 *
	 * @see com.vaadin.data.util.converter.Converter#getPresentationType()
	 */
	@Override
	public Class<String> getPresentationType() {
		return String.class;
	}

}