/* Copyright (C) 2001, 2007 United States Government as represented by
the Administrator of the National Aeronautics and Space Administration.
All Rights Reserved.
*/
package gov.nasa.worldwind.layers.rpf.wizard;

/**
 * @author dcollins
 * @version $Id: TimeFormatter.java 4529 2008-02-20 03:27:48Z dcollins $
 */
public class TimeFormatter
{
    private static final long ONE_HOUR   = 60L * 60L * 1000L;
    private static final long ONE_MINUTE = 60L * 1000L;
    private static final long ONE_SECOND = 1000L;

    public TimeFormatter()
    {}

    public String formatPrecise(long millis)
    {
        long[] hms = millisToHMS(millis);
        return String.format("%02d:%02d:%02d", hms[0], hms[1], hms[2]);
    }

    public String formatEstimate(long millis)
    {
        String result;

        // Less than a minute.
        if (millis < ONE_MINUTE)
        {
            result = "less than 1 minute";
        }
        // Report time in one-minute increments.
        else if (millis < 10L* ONE_MINUTE)
        {
            millis = ONE_MINUTE * Math.round(millis / (double) ONE_MINUTE);
            long m = millis / ONE_MINUTE;
            result = "about " + m + (m > 1 ? " minutes" : " minute");
        }
        // Report time in ten-minute increments.
        else if (millis < 55L * ONE_MINUTE)
        {
            millis = 10L * ONE_MINUTE * Math.round(millis / (10d * ONE_MINUTE));
            long m = millis / ONE_MINUTE;
            result = "about " + m + " minutes";
        }
        // Report time in half-hour increments.
        else
        {
            millis = 30L * ONE_MINUTE * Math.round(millis / (30d * ONE_MINUTE));
            long h = millis / ONE_HOUR;
            result = "about " + h + (h > 1 ? " hours" : " hour");
            long m = (millis / ONE_MINUTE) % 60L;
            if (m > 0)
                result += " " + m + " minutes";
        }

        return result;
    }

    private static long[] millisToHMS(long millis)
    {
        return new long[] {
            (long) (Math.floor(millis / (double) ONE_HOUR)   % 60d),  // hours
            (long) (Math.floor(millis / (double) ONE_MINUTE) % 60d),  // minutes
            (long) (Math.floor(millis / (double) ONE_SECOND) % 60d)}; // seconds

    }
}