full/module/finance/wallet/internal/logic/wechat/wx_callback.go

package wechat

import (
	"context"
	"encoding/json"

	"bsm/full/module/finance/wallet/internal/config"
	"bsm/full/module/finance/wallet/internal/models"
	pb "bsm/full/module/finance/wallet/pb"
	"git.apinb.com/bsm-sdk/core/errcode"
	"git.apinb.com/bsm-sdk/core/printer"
	"github.com/go-pay/gopay/wechat/v3"
)

// 微信支付回调
// 完成验签与解密后，按商户订单号反查本地支付单、核对金额，
// 条件更新为支付成功并在同一事务内入账写流水。
func WxCallback(ctx context.Context, in *pb.WxCallBackRequest) (reply *pb.CallBackReply, err error) {
	var notifyReq = &wechat.V3NotifyReq{}
	data, err := json.Marshal(in)
	if err != nil {
		return nil, errcode.ErrJsonMarshal
	}
	err = json.Unmarshal(data, &notifyReq)
	if err != nil {
		return nil, errcode.ErrJsonUnmarshal
	}

	wx, err := NewWechat()
	if err != nil {
		printer.Error(err.Error())
		return &pb.CallBackReply{Code: "FAIL", Message: "支付客户端初始化失败"}, nil
	}
	pubKey := wx.Client.WxPublicKeyMap()
	err = notifyReq.VerifySignByPKMap(pubKey)
	if err != nil {
		printer.Error(err.Error())
		return &pb.CallBackReply{Code: "FAIL", Message: "验签失败"}, nil
	}
	res, err := notifyReq.DecryptPayCipherText(config.Spec.WeChat.APIV3Key)
	if err != nil {
		printer.Error(err.Error())
		return &pb.CallBackReply{Code: "FAIL", Message: "解密失败"}, err
	}

	// 仅处理支付成功通知，其余状态直接应答，避免渠道重复推送
	if res.TradeState != "SUCCESS" {
		return &pb.CallBackReply{Code: "SUCCESS", Message: res.TradeState}, nil
	}
	if res.Amount == nil {
		return &pb.CallBackReply{Code: "FAIL", Message: "金额缺失"}, nil
	}

	// 结算：金额核对 + 条件更新为成功 + 事务内入账写流水（幂等）
	if err := models.SettlePaymentSuccess(res.OutTradeNo, res.TransactionId, int64(res.Amount.Total)); err != nil {
		printer.Error(err.Error())
		return &pb.CallBackReply{Code: "FAIL", Message: "结算失败"}, nil
	}

	return &pb.CallBackReply{Code: "SUCCESS", Message: "SUCCESS"}, nil
}