/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.activemq.util;

import java.text.DecimalFormat;
import java.text.DecimalFormatSymbols;
import java.text.NumberFormat;
import java.util.Locale;

/**
 * Time utilities.
 */
public final class TimeUtils {

    private TimeUtils() {
    }

    /**
     * Prints the duration in a human readable format as X days Y hours Z minutes etc.
     *
     * @param uptime the up-time in milliseconds
     *
     * @return the time used for displaying on screen or in logs
     */
    public static String printDuration(double uptime) {
        // Code taken from Karaf
        // https://svn.apache.org/repos/asf/karaf/trunk/shell/commands/src/main/java/org/apache/karaf/shell/commands/impl/InfoAction.java

        NumberFormat fmtI = new DecimalFormat("###,###", new DecimalFormatSymbols(Locale.ENGLISH));
        NumberFormat fmtD = new DecimalFormat("###,##0.000", new DecimalFormatSymbols(Locale.ENGLISH));

        uptime /= 1000;
        if (uptime < 60) {
            return fmtD.format(uptime) + " seconds";
        }
        uptime /= 60;
        if (uptime < 60) {
            long minutes = (long) uptime;
            String s = fmtI.format(minutes) + (minutes > 1 ? " minutes" : " minute");
            return s;
        }
        uptime /= 60;
        if (uptime < 24) {
            long hours = (long) uptime;
            long minutes = (long) ((uptime - hours) * 60);
            String s = fmtI.format(hours) + (hours > 1 ? " hours" : " hour");
            if (minutes != 0) {
                s += " " + fmtI.format(minutes) + (minutes > 1 ? " minutes" : " minute");
            }
            return s;
        }
        uptime /= 24;
        long days = (long) uptime;
        long hours = (long) ((uptime - days) * 24);
        String s = fmtI.format(days) + (days > 1 ? " days" : " day");
        if (hours != 0) {
            s += " " + fmtI.format(hours) + (hours > 1 ? " hours" : " hour");
        }

        return s;
    }
}
