<?php

namespace XuanChen\UnionPay\Action;


use Illuminate\Http\Request;

class Init
{
    public $params;
    public $sign;

    /**
     * RSA验签
     * @param $params 待签名数据
     * @param $public_key 公钥字符串
     * @param $sign 要校对的的签名结果
     * return 验证结果
     */
    public function checkSign($self = false)
    {
        $sign = $this->sign;
        $sign = base64_decode($sign);
        
        $public_key = $this->getPublic($self);

        $pub_key_id = openssl_get_publickey($public_key);

        $signStr = $this->getSignString($this->params);

        if ($pub_key_id) {
            $result = (bool)openssl_verify($signStr, $sign, $pub_key_id);
            openssl_free_key($pub_key_id);
        } else {
            return '公钥格式有误!';
        }

        return $result;
    }

    /**
     * Notes: 签名
     * @Author: 玄尘
     * @Date: 2020/9/29 9:56
     * @return string
     */
    public function getSign()
    {
        $signStr = $this->getSignString();
        $private_key = $this->getPrivate();

        $privKeyId = openssl_pkey_get_private($private_key);
        if (!$privKeyId) {
            return '私钥格式有误';
        }

        openssl_sign($signStr, $signature, $privKeyId);
        openssl_free_key($privKeyId);

        return base64_encode($signature);
    }

    /**
     * 获取待签名字符串
     * @param array $params 参数数组
     * @return   string
     */
    public function getSignString()
    {
        $params = array_filter($this->params);
        ksort($params);
        $signStr = http_build_query($params);
        return $signStr;
    }

    //获取私钥
    public function getPrivate()
    {
        $private = config('unionpay.check.self.private');

        if (!file_exists($private)) {
            throw new \Exception('缺少私钥文件');
        }

        return file_get_contents($private);
    }

    //获取公钥
    public function getPublic($self = false)
    {
        $public = config('unionpay.check.unionpay.public');

        if ($self) {
            $public = config('unionpay.check.self.public');
        }

        return file_get_contents($public);
    }

}