<?php

namespace app\common\library\wechat;

use app\common\model\Wxapp as WxappModel;
use app\task\model\Setting as SettingModel;
use app\common\library\sms\Driver as SmsDriver;
use app\common\exception\BaseException;

/**
 * 微信支付
 * Class WxPay
 * @package app\common\library\wechat
 */
class WxPay
{
    private $config; // 微信支付配置
    private $error;

    /**
     * 构造方法
     * WxPay constructor.
     * @param $config
     */
    public function __construct($config)
    {
        $this->config = $config;
    }

    /**
     * 统一下单API
     * @param $order_no
     * @param $openid
     * @param $total_fee
     * @return array
     * @throws BaseException
     */
    public function unifiedorder($order_no, $openid, $total_fee)
    {
        // 当前时间
        $time = time();
        // 生成随机字符串
        $nonceStr = md5($time . $openid);
        // API参数
        $params = [
            'appid' => $this->config['app_id'],
            'attach' => 'test',
            'body' => $order_no,
            'mch_id' => $this->config['mchid'],
            'nonce_str' => $nonceStr,
            'notify_url' => base_url() . 'notice.php',  // 异步通知地址
            'openid' => $openid,
            'out_trade_no' => $order_no,
            'spbill_create_ip' => \request()->ip(),
            'total_fee' => $total_fee * 100, // 价格:单位分
            'trade_type' => 'JSAPI',
        ];
        // 生成签名
        $params['sign'] = $this->makeSign($params);
        // 请求API
        $url = 'https://api.mch.weixin.qq.com/pay/unifiedorder';
        $result = $this->postXmlCurl($this->toXml($params), $url);
        $prepay = $this->fromXml($result);
        // 请求失败
        if ($prepay['return_code'] === 'FAIL') {
            $this->error = $prepay['return_msg'];
            return false;
        }
        if ($prepay['result_code'] === 'FAIL') {
            $this->error = $prepay['return_msg'];
            return false;
        }
        // 生成 nonce_str 供前端使用
        $paySign = $this->makePaySign($params['nonce_str'], $prepay['prepay_id'], $time);
        return [
            'prepay_id' => $prepay['prepay_id'],
            'nonceStr' => $nonceStr,
            'timeStamp' => (string)$time,
            'paySign' => $paySign
        ];
    }

    /**
     * 支付成功异步通知
     * @param \app\task\model\Order $OrderModel
     * @throws BaseException
     * @throws \Exception
     * @throws \think\exception\DbException
     */
    public function notify($OrderModel)
    {
        if (!$xml = file_get_contents('php://input')) {
            $this->returnCode(false, 'Not found DATA');
        }
        // 将服务器返回的XML数据转化为数组
        $data = $this->fromXml($xml);
        // 记录日志
        $this->doLogs($xml);
        $this->doLogs($data);
        // 订单信息
        $order = $OrderModel->payDetail($data['out_trade_no']);
        empty($order) && $this->returnCode(true, '订单不存在');
        // 保存微信服务器返回的签名sign
        $dataSign = $data['sign'];
        // sign不参与签名算法
        unset($data['sign']);
        // 生成签名
        $sign = $this->makeSign($data);
        // 判断签名是否正确  判断支付状态
        if (($sign === $dataSign)
            && ($data['return_code'] == 'SUCCESS')
            && ($data['result_code'] == 'SUCCESS')) {
            // 更新订单状态
            $order->updatePayStatus($data['transaction_id']);
            // 返回状态
            $this->returnCode(true, 'OK');
        }
        // 返回状态
        $this->returnCode(false, '签名失败');
    }

    /**
     * 返回状态给微信服务器
     * @param bool $is_success
     * @param string $msg
     */
    private function returnCode($is_success = true, $msg = null)
    {
        $xml_post = $this->toXml([
            'return_code' => $is_success ? $msg ?: 'SUCCESS' : 'FAIL',
            'return_msg' => $is_success ? 'OK' : $msg,
        ]);
        die($xml_post);
    }

    /**
     * 写入日志记录
     * @param $values
     * @return bool|int
     */
    private function doLogs($values)
    {
        return write_log($values, __DIR__);
    }

    /**
     * 生成paySign
     * @param $nonceStr
     * @param $prepay_id
     * @param $timeStamp
     * @return string
     */
    private function makePaySign($nonceStr, $prepay_id, $timeStamp)
    {
        $data = [
            'appId' => $this->config['app_id'],
            'nonceStr' => $nonceStr,
            'package' => 'prepay_id=' . $prepay_id,
            'signType' => 'MD5',
            'timeStamp' => $timeStamp,
        ];

        //签名步骤一：按字典序排序参数
        ksort($data);

        $string = $this->toUrlParams($data);

        //签名步骤二：在string后加入KEY
        $string = $string . '&key=' . $this->config['apikey'];

        //签名步骤三：MD5加密
        $string = md5($string);

        //签名步骤四：所有字符转为大写
        $result = strtoupper($string);

        return $result;
    }

    /**
     * 将xml转为array
     * @param $xml
     * @return mixed
     */
    private function fromXml($xml)
    {
        // 禁止引用外部xml实体
        libxml_disable_entity_loader(true);
        return json_decode(json_encode(simplexml_load_string($xml, 'SimpleXMLElement', LIBXML_NOCDATA)), true);
    }

    /**
     * 以post方式提交xml到对应的接口url
     * @param $xml
     * @param $url
     * @param int $second
     * @return mixed
     */
    private function postXmlCurl($xml, $url, $second = 30)
    {
        $ch = curl_init();
        // 设置超时
        curl_setopt($ch, CURLOPT_TIMEOUT, $second);
        curl_setopt($ch, CURLOPT_URL, $url);
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, FALSE);
        curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, FALSE);//严格校验
        // 设置header
        curl_setopt($ch, CURLOPT_HEADER, FALSE);
        // 要求结果为字符串且输出到屏幕上
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
        // post提交方式
        curl_setopt($ch, CURLOPT_POST, TRUE);
        curl_setopt($ch, CURLOPT_POSTFIELDS, $xml);
        // 运行curl
        $data = curl_exec($ch);
        curl_close($ch);
        return $data;
    }

    /**
     * 生成签名
     * @param $values
     * @return string 本函数不覆盖sign成员变量，如要设置签名需要调用SetSign方法赋值
     */
    private function makeSign($values)
    {
        //签名步骤一：按字典序排序参数
        ksort($values);
        $string = $this->toUrlParams($values);
        //签名步骤二：在string后加入KEY
        $string = $string . '&key=' . $this->config['apikey'];
        //签名步骤三：MD5加密
        $string = md5($string);
        //签名步骤四：所有字符转为大写
        $result = strtoupper($string);
        return $result;
    }

    /**
     * 格式化参数格式化成url参数
     * @param $values
     * @return string
     */
    private function toUrlParams($values)
    {
        $buff = '';
        foreach ($values as $k => $v) {
            if ($k != 'sign' && $v != '' && !is_array($v)) {
                $buff .= $k . '=' . $v . '&';
            }
        }
        return trim($buff, '&');
    }

    /**
     * 输出xml字符
     * @param $values
     * @return bool|string
     */
    private function toXml($values)
    {
        if (!is_array($values)
            || count($values) <= 0
        ) {
            return false;
        }

        $xml = "<xml>";
        foreach ($values as $key => $val) {
            if (is_numeric($val)) {
                $xml .= "<" . $key . ">" . $val . "</" . $key . ">";
            } else {
                $xml .= "<" . $key . "><![CDATA[" . $val . "]]></" . $key . ">";
            }
        }
        $xml .= "</xml>";
        return $xml;
    }

    public function getError()
    {
        return $this->error;
    }

}