<?php
class WxpayModel
{
//介面API URL字首
    const API_URL_PREFIX = 'https://api.mch.weixin.qq.com';
//下單地址URL
    const UNIFIEDORDER_URL = "/pay/unifiedorder";
//查詢訂單URL
    const ORDERQUERY_URL = "/pay/orderquery";
//關閉訂單URL
    const CLOSEORDER_URL = "/pay/closeorder";
//公眾賬號ID
    private $appid;
//商戶號
    private $mch_id;
//隨機字串
    private $nonce_str;
//簽名
    private $sign;
//商品描述
    private $body;
//商戶訂單號
    private $out_trade_no;
//支付總金額
    private $total_fee;
//終端IP
    private $spbill_create_ip;
//支付結果回撥通知地址
    private $notify_url;
//交易型別
    private $trade_type;
//支付金鑰
    private $key;
//證書路徑
    private $SSLCERT_PATH;
    private $SSLKEY_PATH;
//所有引數
    private $params = array();
    public function __construct($appid, $mch_id, $notify_url, $key)
    {
        $this->appid = $appid;
        $this->mch_id = $mch_id;
        $this->notify_url = $notify_url;
        $this->key = $key;
    }


    /**
     * 隨機數
     * @param $length
     * @param int $numeric
     * @return string
     */
    public function random($length, $numeric = 0)
    {
        PHP_VERSION < '4.2.0' ? mt_srand((double)microtime() * 1000000) : mt_srand();
        $seed = base_convert(md5(print_r($_SERVER, 1) . microtime()), 16, $numeric ? 10 : 35);
        $seed = $numeric ? (str_replace('0', '', $seed) . '012340567890') : ($seed . 'zZ' . strtoupper($seed));
        $hash = '';
        $max = strlen($seed) - 1;
        for ($i = 0; $i < $length; $i++) {
            $hash .= $seed[mt_rand(0, $max)];
        }
        return $hash;
    }




    /**
     * 自定義訂單
     * @return string
     */
    public function setout_trade_no(){


        $time = date("YmdHis",time());
        $random = $this->random(8,0);
        $out_trade_no = '12121'.$time.$random;
        return $out_trade_no;


    }


    /**
     * 下單方法
     * @param $params 下單引數2
     */
    public function unifiedOrder2( $params ){
        $this->body = $params['body'];
        $this->out_trade_no = $params['out_trade_no'];
        $this->total_fee = $params['total_fee'];
        $this->trade_type = $params['trade_type'];
        $this->nonce_str = $this->genRandomString();
        $this->spbill_create_ip = $_SERVER['REMOTE_ADDR'];
        $this->params['appid'] = $this->appid;
        $this->params['mch_id'] = $this->mch_id;
        $this->params['nonce_str'] = $this->nonce_str;
        $this->params['body'] = $this->body;
        $this->params['out_trade_no'] = $this->out_trade_no;
        $this->params['total_fee'] = $this->total_fee;
        $this->params['spbill_create_ip'] = $this->spbill_create_ip;
        $this->params['notify_url'] = $this->notify_url;
        $this->params['openid'] = $params['openid'];


        $this->params['trade_type'] = $this->trade_type;


//獲取簽名資料
        $this->sign = $this->MakeSign( $this->params );
        $this->params['sign'] = $this->sign;
        $xml = $this->data_to_xml($this->params);
        $response = $this->postXmlCurl($xml, self::API_URL_PREFIX.self::UNIFIEDORDER_URL);
        if( !$response ){
            return false;
        }
        $result = $this->xml_to_data( $response );
        if( !empty($result['result_code']) && !empty($result['err_code']) ){
            $result['err_msg'] = $this->error_code( $result['err_code'] );
        }
        return $result;
    }






    /**
     * 下單方法
     * @param $params 下單引數
     */
    public function unifiedOrder( $params ){


        $this->body = $params['body'];
        $this->out_trade_no = $params['out_trade_no'];
        $this->total_fee = $params['total_fee'];
        $this->trade_type = $params['trade_type'];
        $this->nonce_str = $this->genRandomString();
        $this->spbill_create_ip = $_SERVER['REMOTE_ADDR'];
        $this->params['appid'] = $this->appid;
        $this->params['mch_id'] = $this->mch_id;
        $this->params['nonce_str'] = $this->nonce_str;
        $this->params['body'] = $this->body;
        $this->params['out_trade_no'] = $this->out_trade_no;
        $this->params['total_fee'] = $this->total_fee;
        $this->params['spbill_create_ip'] = $this->spbill_create_ip;
        $this->params['notify_url'] = $this->notify_url;
        $this->params['trade_type'] = $this->trade_type;
//獲取簽名資料
        $this->sign = $this->MakeSign( $this->params );
        $this->params['sign'] = $this->sign;
        $xml = $this->data_to_xml($this->params);
        $response = $this->postXmlCurl($xml, self::API_URL_PREFIX.self::UNIFIEDORDER_URL);
        if( !$response ){
            return false;
        }
        $result = $this->xml_to_data( $response );
        if( !empty($result['result_code']) && !empty($result['err_code']) ){
            $result['err_msg'] = $this->error_code( $result['err_code'] );
        }
        return $result;
    }
    /**
     * 查詢訂單資訊
     * @param $out_trade_no 訂單號
     * @return array
     */
    public function orderQuery( $out_trade_no ){


        $this->params['appid'] = $this->appid;
        $this->params['mch_id'] = $this->mch_id;
        $this->params['nonce_str'] = $this->genRandomString();
        $this->params['out_trade_no'] = $out_trade_no;
//獲取簽名資料
        $this->sign = $this->MakeSign( $this->params );
        $this->params['sign'] = $this->sign;
        $xml = $this->data_to_xml($this->params);
        $response = $this->postXmlCurl($xml, self::API_URL_PREFIX.self::ORDERQUERY_URL);
        if( !$response ){
            return false;
        }
        $result = $this->xml_to_data( $response );
        if( !empty($result['result_code']) && !empty($result['err_code']) ){
            $result['err_msg'] = $this->error_code( $result['err_code'] );
        }
        return $result;
    }
    /**
     * 關閉訂單
     * @param $out_trade_no 訂單號
     * @return array
     */
    public function closeOrder( $out_trade_no ){
        $this->params['appid'] = $this->appid;
        $this->params['mch_id'] = $this->mch_id;
        $this->params['nonce_str'] = $this->genRandomString();
        $this->params['out_trade_no'] = $out_trade_no;
//獲取簽名資料
        $this->sign = $this->MakeSign( $this->params );
        $this->params['sign'] = $this->sign;
        $xml = $this->data_to_xml($this->params);
        $response = $this->postXmlCurl($xml, self::API_URL_PREFIX.self::CLOSEORDER_URL);
        if( !$response ){
            return false;
        }
        $result = $this->xml_to_data( $response );
        return $result;
    }
    /**
     *
     * 獲取支付結果通知資料
     * return array
     */
    public function getNotifyData(){
//獲取通知的資料
        $xml = $GLOBALS['HTTP_RAW_POST_DATA'];
        //$xml = file_get_contents('php://input');
        $data = array();
        if( empty($xml) ){
            return false;
        }
        $data = $this->xml_to_data( $xml );
        if( !empty($data['return_code']) ){
            if( $data['return_code'] == 'FAIL' ){
                return false;
            }
        }
        return $data;
    }
    /**
     * 接收通知成功後應答輸出XML資料
     * @param string $xml
     */
    public function replyNotify(){
        /*  ksort($data);
          $buff = '';
          foreach ($data as $k => $v){
              if($k != 'sign'){
                  $buff .= $k . '=' . $v . '&';
              }
          }
          $stringSignTemp = $buff . 'key=a1M5s4s6a4r8t4g2h3Md36AlJ8s7f5sd';//key為證書金鑰
          $sign = strtoupper(md5($stringSignTemp));
  //判斷算出的簽名和通知資訊的簽名是否一致
          if($sign == $data['sign']){
              //處理完成之後，告訴微信成功結果
              echo '<xml>
                <return_code><![CDATA[SUCCESS]]></return_code>
                <return_msg><![CDATA[OK]]></return_msg>
            </xml>';
              exit();
          }
  */
        $data['return_code'] = 'SUCCESS';
        $data['return_msg'] = 'OK';
        $xml = $this->data_to_xml( $data );
        echo $xml;
        die();
    }
    /**
     * 生成APP端支付引數
     * @param $prepayid 預支付id
     */
    public function getAppPayParams( $prepayid ){
        $data['appid'] = $this->appid;
        $data['partnerid'] = $this->mch_id;
        $data['prepayid'] = $prepayid;
        $data['package'] = 'Sign=WXPay';
        $data['noncestr'] = $this->genRandomString();
        $data['timestamp'] = time();
        $data['sign'] = $this->MakeSign( $data );
        return $data;
    }
    /**
     * 生成簽名
     * @return 簽名
     */
    public function MakeSign( $params ){
//簽名步驟一：按字典序排序陣列引數
        ksort($params);
        $string = $this->ToUrlParams($params);
//簽名步驟二：在string後加入KEY
        $string = $string . "&key=".$this->key;
//簽名步驟三：MD5加密
        $string = md5($string);
//簽名步驟四：所有字元轉為大寫
        $result = strtoupper($string);
        return $result;
    }
    /**
     * 將引數拼接為url: key=value&key=value
     * @param $params
     * @return string
     */
    public function ToUrlParams( $params ){
        $string = '';
        if( !empty($params) ){
            $array = array();
            foreach( $params as $key => $value ){
                $array[] = $key.'='.$value;
            }
            $string = implode("&",$array);
        }
        return $string;
    }
    /**
     * 輸出xml字元
     * @param $params 引數名稱
     * return string 返回組裝的xml
     **/
    public function data_to_xml( $params ){
        if(!is_array($params)|| count($params) <= 0)
        {
            return false;
        }
        $xml = "<xml>";
        foreach ($params as $key=>$val)
        {
            if (is_numeric($val)){
                $xml.="<".$key.">".$val."</".$key.">";
            }else{
                $xml.="<".$key."><![CDATA[".$val."]]></".$key.">";
            }
        }
        $xml.="</xml>";
        return $xml;
    }
    /**
     * 將xml轉為array
     * @param string $xml
     * return array
     */
    public function xml_to_data($xml){
        if(!$xml){
            return false;
        }
//將XML轉為array
//禁止引用外部xml實體
        libxml_disable_entity_loader(true);
        $data = json_decode(json_encode(simplexml_load_string($xml, 'SimpleXMLElement', LIBXML_NOCDATA)), true);
        return $data;
    }
    /**
     * 獲取毫秒級別的時間戳
     */
    public static function getMillisecond(){
//獲取毫秒的時間戳
        $time = explode ( " ", microtime () );
        $time = $time[1] . ($time[0] * 1000);
        $time2 = explode( ".", $time );
        $time = $time2[0];
        return $time;
    }
    /**
     * 產生一個指定長度的隨機字串,並返回給使用者
     * @param type $len 產生字串的長度
     * @return string 隨機字串
     */
    public function genRandomString($len = 32) {
        $chars = array(
            "a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k",
            "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v",
            "w", "x", "y", "z", "A", "B", "C", "D", "E", "F", "G",
            "H", "I", "J", "K", "L", "M", "N", "O", "P", "Q", "R",
            "S", "T", "U", "V", "W", "X", "Y", "Z", "0", "1", "2",
            "3", "4", "5", "6", "7", "8", "9"
        );
        $charsLen = count($chars) - 1;
// 將陣列打亂
        shuffle($chars);
        $output = "";
        for ($i = 0; $i < $len; $i++) {
            $output .= $chars[mt_rand(0, $charsLen)];
        }
        return $output;
    }
    /**
     * 以post方式提交xml到對應的介面url
     *
     * @param string $xml 需要post的xml資料
     * @param string $url url
     * @param bool $useCert 是否需要證書，預設不需要
     * @param int $second url執行超時時間，預設30s
     * @throws WxPayException
     */
    public function postXmlCurl($xml, $url, $useCert = false, $second = 30){
        $ch = curl_init();
//設定超時
        curl_setopt($ch, CURLOPT_TIMEOUT, $second);
        curl_setopt($ch,CURLOPT_URL, $url);
        curl_setopt($ch,CURLOPT_SSL_VERIFYPEER,FALSE);
        curl_setopt($ch,CURLOPT_SSL_VERIFYHOST,2);
//設定header
        curl_setopt($ch, CURLOPT_HEADER, FALSE);
//要求結果為字串且輸出到螢幕上
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
        if($useCert == true){
//設定證書
//使用證書：cert 與 key 分別屬於兩個.pem檔案
            curl_setopt($ch,CURLOPT_SSLCERTTYPE,'PEM');
//curl_setopt($ch,CURLOPT_SSLCERT, WxPayConfig::SSLCERT_PATH);
            curl_setopt($ch,CURLOPT_SSLKEYTYPE,'PEM');
//curl_setopt($ch,CURLOPT_SSLKEY, WxPayConfig::SSLKEY_PATH);
        }
//post提交方式
        curl_setopt($ch, CURLOPT_POST, TRUE);
        curl_setopt($ch, CURLOPT_POSTFIELDS, $xml);
//執行curl
        $data = curl_exec($ch);
//返回結果
        if($data){
            curl_close($ch);
            return $data;
        } else {
            $error = curl_errno($ch);
            curl_close($ch);
            return false;
        }
    }
    /**
     * 錯誤程式碼
     * @param $code 伺服器輸出的錯誤程式碼
     * return string
     */
    public function error_code( $code ){
        $errList = array(
            'NOAUTH' => '商戶未開通此介面許可權',
            'NOTENOUGH' => '使用者帳號餘額不足',
            'ORDERNOTEXIST' => '訂單號不存在',
            'ORDERPAID' => '商戶訂單已支付，無需重複操作',
            'ORDERCLOSED' => '當前訂單已關閉，無法支付',
            'SYSTEMERROR' => '系統錯誤!系統超時',
            'APPID_NOT_EXIST' => '引數中缺少APPID',
            'MCHID_NOT_EXIST' => '引數中缺少MCHID',
            'APPID_MCHID_NOT_MATCH' => 'appid和mch_id不匹配',
            'LACK_PARAMS' => '缺少必要的請求引數',
            'OUT_TRADE_NO_USED' => '同一筆交易不能多次提交',
            'SIGNERROR' => '引數簽名結果不正確',
            'XML_FORMAT_ERROR' => 'XML格式錯誤',
            'REQUIRE_POST_METHOD' => '未使用post傳遞引數 ',
            'POST_DATA_EMPTY' => 'post資料不能為空',
            'NOT_UTF8' => '未使用指定編碼格式',
        );
        if( array_key_exists( $code , $errList ) ){
            return $errList[$code];
        }
    }
}

//微信小程式支付
$total_fee = $total_fee*100;
$wxpay  = new WxpayModel($appid, $mch_id, $notify_url, $key);


$body = '';
$order = $wxpay->setout_trade_no();
$params = array(
    'body'=>$body,
    'out_trade_no'=>$order,
    'total_fee'=>$total_fee,
    'trade_type'=>'JSAPI',
    'openid'=>$openid,
);




$res = $wxpay->unifiedOrder2( $params );


if ($res[return_code]!='SUCCESS'){
    $this->returnData('','失敗',100);
}


$timeStamp = time();
$data = array();


$data['appId'] = $res[appid];
$data['timeStamp'] = "$timeStamp";
$data['nonceStr'] = $wxpay->genRandomString();
$data['package'] = 'prepay_id='.$res[prepay_id];
$data['signType'] = 'MD5';

$data['paySign'] = $wxpay->MakeSign($data);