Human Readable Time String with PHP

common.php

<?php
/**
 * Get time elapsed string from given between dates by human readable format
 *
 * @param string $date_now: current date
 * @param string $date_old: target old date
 * @param bool $full: need full date ago string
 *
 * @see source: https://stackoverflow.com/a/18602474
 *
 * @return array|bool
 */
function timeElapsed($date_now, $date_old)
{
    $old = new DateTime($date_old);
    $now = new DateTime($date_now);
    $diff = $now->diff($old);

    $diff->w = floor($diff->d / 7);
    $diff->d -= $diff->w * 7;

    $string = array(
        'y' => 'year',
        'm' => 'month',
        'w' => 'week',
        'd' => 'day',
        'h' => 'hour',
        'i' => 'minute',
        's' => 'second',
    );
    foreach ($string as $k => &$v) {
        if ($diff->$k) {
            $v = $diff->$k . ',' . $v . ($diff->$k > 1 ? 's' : '');
        } else {
            unset($string[$k]);
        }
    }

    if ($string && is_array($string) && count($string) > 0) {
        $parse_ago = explode(',', $string[key(array_slice($string, 0, 1))]);

        return [
            'count' => $parse_ago[0],
            'time_part' => $parse_ago[1],
        ];
    } else {
        return [
            'count' => false,
            'time_part' => 'just_now',
        ];
    }

    return false;
}

// returns only one unit, x years, 5 months, 1 day
print_r(timeElapsed(date('Y-m-d H:i:s', time()), '2012-12-12 12:12:12'));