<?php

class FddCryptUtil
{


    public function signature($timestamp,$appSecret,$values){
        $keys = array_keys($values);
        array_multisort($keys, SORT_ASC, SORT_STRING);
        $sortParam = $this->arrayParamToStr($values, $keys);
//        print_r($sortParam."\n");
        //计算签名
        $signText = strtolower(hash("sha256", $sortParam));
        $hash = hash_hmac("sha256", $timestamp, $appSecret, true);
        return hash_hmac("sha256", $signText, $hash);
    }

    private function arrayParamToStr($array, $keys){
        $Str = "";
        foreach($keys as $k => $v){
            if(!empty($array[$v])){
                $Str .= $v."=".$array[$v]."&";
            }
        }
        return trim($Str,"&");
    }

    public function msectime(){
        list($msec, $sec) = explode(' ', microtime());
        $msectime = (float)sprintf('%.0f', (floatval($msec) + floatval($sec)) * 1000);
        return $msectime;
    }
}