package zhios_pay_utils

import (
	"crypto"
	"crypto/rand"
	"crypto/rsa"
	"crypto/sha1"
	"crypto/x509"
	"encoding/base64"
	"encoding/pem"
	"errors"
	"fmt"
	"golang.org/x/crypto/ssh"
	"sort"
	"strings"
)

func GetSign(privateKeyStr, data string) (string, error) {
	privateKey, err := ssh.ParseRawPrivateKey([]byte(privateKeyStr))
	if err != nil {
		return "", err
	}
	fmt.Println(privateKey.(*rsa.PrivateKey))
	fmt.Println(data)
	h := crypto.Hash.New(crypto.SHA256)
	h.Write([]byte(data))
	hashed := h.Sum(nil)
	sign, err := rsa.SignPKCS1v15(rand.Reader, privateKey.(*rsa.PrivateKey), crypto.SHA256, hashed)
	if err != nil {
		return "", nil
	}
	return base64.StdEncoding.EncodeToString(sign), nil
}

func GetSignV2(privateKeyStr, data string, hash crypto.Hash) (string, error) {
	privateKey, err := ssh.ParseRawPrivateKey([]byte(privateKeyStr))
	if err != nil {
		return "", err
	}
	h := crypto.Hash.New(hash)
	h.Write([]byte(data))
	hashed := h.Sum(nil)
	sign, err := rsa.SignPKCS1v15(rand.Reader, privateKey.(*rsa.PrivateKey), hash, hashed)
	if err != nil {
		return "", nil
	}
	return base64.StdEncoding.EncodeToString(sign), nil
}

// RSA2公钥验证签名
func Rsa2PubCheckSign(signContent, sign, publicKey string, hash crypto.Hash) bool {
	hashed := sha1.Sum([]byte(signContent))
	pubKey, err := ParsePublicKey(publicKey)
	if err != nil {
		return false
	}
	sig, _ := base64.StdEncoding.DecodeString(sign)
	err = rsa.VerifyPKCS1v15(pubKey, hash, hashed[:], sig)
	if err != nil {
		return false
	}
	return true
}

// 解析公钥
func ParsePublicKey(publicKey string) (*rsa.PublicKey, error) {
	block, _ := pem.Decode([]byte(publicKey))
	if block == nil {
		return nil, errors.New("公钥信息错误！")
	}
	pubKey, err := x509.ParsePKIXPublicKey(block.Bytes)
	if err != nil {
		return nil, err
	}
	return pubKey.(*rsa.PublicKey), nil
}

//◆ 参数名ASCII码从小到大排序（字典序）；
//◆ 如果参数的值为空不参与签名；
//◆ 参数名区分大小写；
//◆ 接口請求成功時，需對返回參數使用平台提供的公鑰進行驗簽，传送的sign参数不参与签名，将生成的签名与该sign值作校验。
//
//  JoinStringsInASCII
//  @Description: 按照规则，参数名ASCII码从小到大排序后拼接
//  @param data 待拼接的数据
//  @param sep 连接符
//  @param onlyValues 是否只包含参数值，true则不包含参数名，否则参数名和参数值均有
//  @param includeEmpty 是否包含空值，true则包含空值，否则不包含，注意此参数不影响参数名的存在
//  @param exceptKeys 被排除的参数名，不参与排序及拼接
//  @return string
//
func JoinStringsInASCII(data map[string]string, sep, KeyValueSep string, onlyValues, includeEmpty bool, exceptKeys ...string) string {
	var list []string
	var keyList []string
	m := make(map[string]int)
	if len(exceptKeys) > 0 {
		for _, except := range exceptKeys {
			m[except] = 1
		}
	}
	for k := range data {
		if _, ok := m[k]; ok {
			continue
		}
		value := data[k]
		if !includeEmpty && value == "" {
			continue
		}
		if onlyValues {
			keyList = append(keyList, k)
		} else {
			list = append(list, fmt.Sprintf("%s%s%s", k, KeyValueSep, value))
		}
	}
	if onlyValues {
		sort.Strings(keyList)
		for _, v := range keyList {
			list = append(list, data[v])
		}
	} else {
		sort.Strings(list)
	}
	return strings.Join(list, sep)
}