/*******************************************************************************
 * Copyright (c) 2012 Original authors and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     Original authors and others - initial API and implementation
 ******************************************************************************/
package org.eclipse.nebula.widgets.nattable.data.convert;

import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.TimeZone;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.eclipse.nebula.widgets.nattable.Messages;
import org.eclipse.nebula.widgets.nattable.util.ObjectUtils;

/**
 * Converts a java.util.Date object to a given format and vice versa
 */
public class DefaultDateDisplayConverter extends DisplayConverter {

    private static final Log log = LogFactory
            .getLog(DefaultDateDisplayConverter.class);

    private SimpleDateFormat dateFormat;

    /**
     * Convert {@link Date} to {@link String} using the default format from
     * {@link SimpleDateFormat}
     */
    public DefaultDateDisplayConverter() {
        this(null, null);
    }

    public DefaultDateDisplayConverter(TimeZone timeZone) {
        this(null, timeZone);
    }

    /**
     * @param dateFormat
     *            as specified in {@link SimpleDateFormat}
     */
    public DefaultDateDisplayConverter(String dateFormat) {
        this(dateFormat, null);
    }

    public DefaultDateDisplayConverter(String dateFormat, TimeZone timeZone) {
        if (dateFormat != null) {
            this.dateFormat = new SimpleDateFormat(dateFormat);
        } else {
            this.dateFormat = new SimpleDateFormat();
        }

        if (timeZone != null) {
            this.dateFormat.setTimeZone(timeZone);
        }
    }

    @Override
    public Object canonicalToDisplayValue(Object canonicalValue) {
        try {
            if (ObjectUtils.isNotNull(canonicalValue)) {
                return this.dateFormat.format(canonicalValue);
            }
        } catch (Exception e) {
            log.warn(e);
        }
        return canonicalValue;
    }

    @Override
    public Object displayToCanonicalValue(Object displayValue) {
        try {
            return this.dateFormat.parse(displayValue.toString());
        } catch (Exception e) {
            throw new ConversionFailedException(Messages.getString("DefaultDateDisplayConverter.failure", //$NON-NLS-1$
                    new Object[] { displayValue, this.dateFormat.toPattern() }), e);
        }
    }

}