timethat/lib/timethat.js

print time from one date to another

/*
Copyright (c) 2012, Yahoo! Inc. All rights reserved.
Code licensed under the BSD License:
http://yuilibrary.com/license/
*/
var plural = function(n) {
    return ((n < 1 || n > 1) ? 's' : '');
};

exports.calc = function(start, end) {

    if (!start) {
        start = new Date();
    }
    if (!end) {
        end = new Date();
    }
    if (start instanceof Date) {
        start = start.getTime();
    }
    if (end instanceof Date) {
        end = end.getTime();
    }
    var total = end - start,
        diff = {}, str = '';

    diff.seconds_raw = (total / 1000) || 0;

    diff.days = Math.floor(total / 1000 / 60 / 60 / 24);
    total -= diff.days * 1000 * 60 * 60 * 24;

    diff.hours = Math.floor(total / 1000 / 60 /60);
    total -= diff.hours * 1000 * 60 * 60;

    diff.minutes = Math.floor(total/ 1000 / 60);
    total -= diff.minutes * 1000 * 60;

    diff.seconds = Math.floor(total / 1000) || 0;

    if (diff.days) {
        str = diff.days + ' day' + plural(diff.days) + ', ';
        str += diff.hours + ' hour' + plural(diff.hours) + ', ';
        str += diff.minutes + ' minute' + plural(diff.minutes) + ', ';
        str += diff.seconds + ' second' + plural(diff.seconds);
    } else if (diff.hours) {
        str = diff.hours + ' hour' + plural(diff.hours) + ', ';
        str += diff.minutes + ' minute' + plural(diff.minutes) + ', ';
        str += diff.seconds + ' second' + plural(diff.seconds);
    } else if (diff.minutes) {
        str = diff.minutes + ' minute' + plural(diff.minutes) + ', ' + diff.seconds + ' second' + plural(diff.seconds);
    } else {
        str = diff.seconds_raw + ' second' + plural(diff.seconds_raw);
    }

    return str;
};