/*
 * Copyright 2012-2015 Red Hat, Inc.
 *
 * This file is part of Thermostat.
 *
 * Thermostat is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published
 * by the Free Software Foundation; either version 2, or (at your
 * option) any later version.
 *
 * Thermostat is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Thermostat; see the file COPYING.  If not see
 * <http://www.gnu.org/licenses/>.
 *
 * Linking this code with other modules is making a combined work
 * based on this code.  Thus, the terms and conditions of the GNU
 * General Public License cover the whole combination.
 *
 * As a special exception, the copyright holders of this code give
 * you permission to link this code with independent modules to
 * produce an executable, regardless of the license terms of these
 * independent modules, and to copy and distribute the resulting
 * executable under terms of your choice, provided that you also
 * meet, for each linked independent module, the terms and conditions
 * of the license of that module.  An independent module is a module
 * which is not derived from or based on this code.  If you modify
 * this code, you may extend this exception to your version of the
 * library, but you are not obligated to do so.  If you do not wish
 * to do so, delete this exception statement from your version.
 */

package com.redhat.thermostat.shared.perflog.internal;

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

class TimeStampProvider {
    
    static final String SEPARATOR = "|";

    static final String ISO_FORMAT_WITH_MILLIS = "yyyy-MM-dd'T'HH:mm:ss.SSSZ";
    private final DateSource source;
    private final DateFormat dateFormat;
    
    TimeStampProvider() {
        this(new DateSource());
    }
    
    // for testing
    TimeStampProvider(DateSource source) {
        this.source = source; 
        this.dateFormat = new SimpleDateFormat(ISO_FORMAT_WITH_MILLIS);
    }

    public String getTimeStamp() {
        return dateFormat.format(source.getDate()) + SEPARATOR;
    }
    
    static class DateSource {
        Date getDate() {
            return new Date();
        }
    }

}