package config

import (
	"fmt"
	"strings"

	"lone-services/pkg/utils"
	wxpay "lone-services/pkg/wechat/pay"
)

func NewWechatPayConfig(clientCode string) (wxpay.Config, error) {
	if clientCode == utils.StringEmpty {
		return wxpay.Config{}, fmt.Errorf("wechat pay client_code empty")
	}

	prefix := "wechat." + clientCode
	alias := clientAppAlias(clientCode)

	appID := firstNonEmpty(
		utils.GetConfigString(prefix+".app_id"),
		utils.GetConfigString(prefix+".appid"),
		utils.GetConfigString("wechat."+alias+"_appid"),
		utils.GetConfigString("wechat.appid"),
		utils.GetConfigString("wechat.app_id"),
	)
	mchID := firstNonEmpty(
		utils.GetConfigString(prefix+".pay_mchid"),
		utils.GetConfigString("wechat.pay_mchid"),
	)
	serialNo := firstNonEmpty(
		utils.GetConfigString(prefix+".pay_serial_no"),
		utils.GetConfigString("wechat.pay_serial_no"),
	)
	privateKeyPath := firstNonEmpty(
		utils.GetConfigString(prefix+".pay_private_key_path"),
		utils.GetConfigString("wechat.pay_private_key_path"),
	)
	platformCertPath := firstNonEmpty(
		utils.GetConfigString(prefix+".pay_platform_cert_path"),
		utils.GetConfigString("wechat.pay_platform_cert_path"),
	)
	apiV3Key := firstNonEmpty(
		utils.GetConfigString(prefix+".pay_apiv3_key"),
		utils.GetConfigString("wechat.pay_apiv3_key"),
	)
	notifyURL := firstNonEmpty(
		utils.GetConfigString(prefix+".pay_notify_url"),
		utils.GetConfigString("wechat.pay_notify_url"),
	)

	if appID == utils.StringEmpty || mchID == utils.StringEmpty || serialNo == utils.StringEmpty ||
		privateKeyPath == utils.StringEmpty || apiV3Key == utils.StringEmpty {
		return wxpay.Config{}, fmt.Errorf("wechat pay config missing for client %s", clientCode)
	}

	return wxpay.Config{
		AppID:               appID,
		MchID:               mchID,
		CertificateSerialNo: serialNo,
		PrivateKeyPath:      privateKeyPath,
		PlatformCertPath:    platformCertPath,
		APIv3Key:            apiV3Key,
		NotifyURL:           notifyURL,
	}, nil
}

func clientAppAlias(clientCode string) string {
	if i := strings.IndexByte(clientCode, '_'); i > 0 {
		return clientCode[:i]
	}
	return clientCode
}

func firstNonEmpty(values ...string) string {
	for _, v := range values {
		if v != utils.StringEmpty {
			return v
		}
	}
	return utils.StringEmpty
}