Time.php

<?php
namespace SmartData;

abstract class Time
{
    // Microsecond
    const uSECOND = 1;
    const mSECOND = self::uSECOND * 1000;
    const SECOND  = self::mSECOND * 1000;
    const MINUTE  = self::SECOND  * 60;
    const HOUR    = self::MINUTE  * 60;
    const DAY     = self::HOUR    * 24;
    const WEEK    = self::DAY     * 7;
    const MONTH   = self::DAY     * 30;
    const YEAR    = self::DAY     * 365;

    public static function now() {
        return (int)round(microtime(true)*1000*1000);
    }

    public static function time_to_date($time) {
        return date('d/m/Y H:i:s', $time/1000000);
    }
}