/* -*- tab-width: 4 -*-
 *
 * Electric(tm) VLSI Design System
 *
 * File: ElapseTimer.java
 *
 * Copyright (c) 2010, Static Free Software. All rights reserved.
 *
 * Electric(tm) 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 3 of the License, or
 * (at your option) any later version.
 *
 * Electric(tm) 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 this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package com.sun.electric.api.minarea.launcher;

import java.io.Serializable;

/**
 * @author Felix Schmidt
 * 
 */
public class ElapseTimer implements Serializable {

    private long start = 0;
    private long end = 0;

    private long now() {
        return System.currentTimeMillis();
    }

    public long getStart() {
        return start;
    }

    public long getEnd() {
        return end;
    }

    public long getTime() {
        return end - start;
    }

    public static ElapseTimer createInstance() {
        return new ElapseTimer();
    }

    public static ElapseTimer createInstanceByValues(long start, long end) {
        ElapseTimer result = new ElapseTimer();
        result.start = start;
        result.end = end;
        return result;
    }

    public ElapseTimer start() {
        this.start = now();
        return this;
    }

    public ElapseTimer end() {
        this.end = now();
        return this;
    }

    /*
     * (non-Javadoc)
     * 
     * @see java.lang.Object#toString()
     */
    @Override
    public String toString() {
        return this.getElapsedTime(getTime());
    }

    public Long toLong() {
        return this.end - this.start;
    }

    public void print(String preText) {
        System.out.println(preText + this.toString());
    }

    /**
     * Method to describe a time value as a String.
     * 
     * @param milliseconds
     *            the time span in milli-seconds.
     * @return a String describing the time span with the format: days : hours :
     *         minutes : seconds
     */
    private String getElapsedTime(long milliseconds) {
        if (milliseconds < 60000) {
            // less than a minute: show fractions of a second
            return (milliseconds / 1000.0) + " secs";
        }
        StringBuffer buf = new StringBuffer();
        int seconds = (int) milliseconds / 1000;
        if (seconds < 0) {
            seconds = 0;
        }
        int days = seconds / 86400;
        if (days > 0) {
            buf.append(days + " days, ");
        }
        seconds = seconds - (days * 86400);
        int hours = seconds / 3600;
        if (hours > 0) {
            buf.append(hours + " hrs, ");
        }
        seconds = seconds - (hours * 3600);
        int minutes = seconds / 60;
        if (minutes > 0) {
            buf.append(minutes + " mins, ");
        }
        seconds = seconds - (minutes * 60);
        buf.append(seconds + " secs");
        return buf.toString();
    }
}
