<?php
/**
 * Created by PhpStorm.
 * User: Administrator
 * Date: 15-5-14
 * Time: 上午9:36
 */
class LangUtils
{
    private static $REGEX = '/^(?:(?!0000)[0-9]{4}(?:(?:0[1-9]|1[0-2])(?:0[1-9]|1[0-9]|2[0-8])|(?:0[13-9]|1[0-2])(?:29|30)|(?:0[13578]|1[02])31)|(?:[0-9]{2}(?:0[48]|[2468][048]|[13579][26])|(?:0[48]|[2468][048]|[13579][26])00)0229)$/i';
    public static function validateDate($date)
    {
        if($date == null)
        {
            return false;
        }
        if(!preg_match(LangUtils::$REGEX,$date))
        {
            return false;
        }
        return strtotime($date) < time();
    }

    public static function randomUUID() {    //可以指定前缀
        $str = md5(uniqid(mt_rand(), true));
        $uuid  = substr($str,0,8) . '-';
        $uuid .= substr($str,8,4) . '-';
        $uuid .= substr($str,12,4) . '-';
        $uuid .= substr($str,16,4) . '-';
        $uuid .= substr($str,20,12);
        return $uuid;
    }
}