package payCenter

import (
	"crypto/md5"
	"crypto/subtle"
	"encoding/hex"
	"errors"
	"net/url"
	"strconv"
	"strings"
	"time"
)

// Conf 与 girl 的 newPayCenter 配置保持一致，App 和 Web 各自加载本进程配置。
type Conf struct {
	AppName     string `yaml:"appName"`
	CallbackUrl string `yaml:"callbackUrl"`
	ApiUrl      string `yaml:"apiUrl"`
	MercID      string `yaml:"mercID"`
	MercSecret  string `yaml:"mercSecret"`
}

var payCenterConf Conf

func Init(c Conf) {
	c.ApiUrl = strings.TrimRight(strings.TrimSpace(c.ApiUrl), "/")
	c.CallbackUrl = strings.TrimRight(strings.TrimSpace(c.CallbackUrl), "/")
	payCenterConf = c
}

// validateConfig 仅在支付请求时校验，配置暂未填写不影响其他业务启动。
func validateConfig(requireCallback bool) error {
	if payCenterConf.MercID == "" || payCenterConf.MercSecret == "" || !validHTTPURL(payCenterConf.ApiUrl) {
		return errors.New("新支付中心配置不完整：请配置 newPayCenter.apiUrl、mercID、mercSecret")
	}
	if requireCallback && (payCenterConf.AppName == "" || !validHTTPURL(payCenterConf.CallbackUrl)) {
		return errors.New("新支付中心配置不完整：请配置 newPayCenter.appName、callbackUrl")
	}
	return nil
}

func validHTTPURL(value string) bool {
	u, err := url.Parse(value)
	return err == nil && (u.Scheme == "http" || u.Scheme == "https") && u.Host != "" && u.User == nil && u.RawQuery == "" && u.Fragment == ""
}

func Generate13DigitString() string {
	return strconv.FormatInt(time.Now().UnixMilli(), 10)
}

func md5Sign(value string) string {
	hash := md5.Sum([]byte(value))
	return hex.EncodeToString(hash[:])
}

func VerifySign(sign, value string) bool {
	return subtle.ConstantTimeCompare([]byte(md5Sign(value)), []byte(sign)) == 1
}

func RChgIDDisassemble(transNo string) string {
	parts := strings.Split(transNo, "-")
	return parts[len(parts)-1]
}