bindbox-game/internal/pkg/pay/client.go

package pay

import (
    "context"
    "errors"

    "bindbox-game/configs"

    "github.com/wechatpay-apiv3/wechatpay-go/core"
    "github.com/wechatpay-apiv3/wechatpay-go/core/option"
    "github.com/wechatpay-apiv3/wechatpay-go/services/payments/jsapi"
    refundsvc "github.com/wechatpay-apiv3/wechatpay-go/services/refunddomestic"
    "github.com/wechatpay-apiv3/wechatpay-go/utils"
)

type WechatPayClient struct {
    client *core.Client
}

// NewWechatPayClient 初始化微信支付客户端
// 入参：context.Context
// 返回：WechatPayClient实例，或错误（配置缺失/私钥加载失败/客户端创建失败）
func NewWechatPayClient(ctx context.Context) (*WechatPayClient, error) {
    cfg := configs.Get()
    if cfg.WechatPay.ApiV3Key == "" {
        return nil, errors.New("wechat pay config incomplete")
    }
    var opts []core.ClientOption
    if cfg.WechatPay.PublicKeyID != "" && cfg.WechatPay.PublicKeyPath != "" {
        if cfg.WechatPay.MchID == "" || cfg.WechatPay.SerialNo == "" || cfg.WechatPay.PrivateKeyPath == "" {
            return nil, errors.New("wechat pay config incomplete")
        }
        mchPrivateKey, err := utils.LoadPrivateKeyWithPath(cfg.WechatPay.PrivateKeyPath)
        if err != nil {
            return nil, err
        }
        pubKey, err := utils.LoadPublicKeyWithPath(cfg.WechatPay.PublicKeyPath)
        if err != nil {
            return nil, err
        }
        opts = []core.ClientOption{option.WithWechatPayPublicKeyAuthCipher(cfg.WechatPay.MchID, cfg.WechatPay.SerialNo, mchPrivateKey, cfg.WechatPay.PublicKeyID, pubKey)}
    } else {
        if cfg.WechatPay.MchID == "" || cfg.WechatPay.SerialNo == "" || cfg.WechatPay.PrivateKeyPath == "" {
            return nil, errors.New("wechat pay config incomplete")
        }
        mchPrivateKey, err := utils.LoadPrivateKeyWithPath(cfg.WechatPay.PrivateKeyPath)
        if err != nil {
            return nil, err
        }
        opts = []core.ClientOption{option.WithWechatPayAutoAuthCipher(cfg.WechatPay.MchID, cfg.WechatPay.SerialNo, mchPrivateKey, cfg.WechatPay.ApiV3Key)}
    }
    client, err := core.NewClient(ctx, opts...)
    if err != nil {
        return nil, err
    }
    return &WechatPayClient{client: client}, nil
}

// JSAPIPrepay 直连商户JSAPI预下单，返回prepay_id
// 入参：appid、mchid、描述、商户订单号、总金额(分)、openid、回调URL
// 返回：prepay_id 或错误
func (c *WechatPayClient) JSAPIPrepay(ctx context.Context, appid, mchid, description, outTradeNo string, total int64, openid, notifyURL string) (string, error) {
    svc := jsapi.JsapiApiService{Client: c.client}
    resp, _, err := svc.Prepay(ctx, jsapi.PrepayRequest{
        Appid:       core.String(appid),
        Mchid:       core.String(mchid),
        Description: core.String(description),
        OutTradeNo:  core.String(outTradeNo),
        NotifyUrl:   core.String(notifyURL),
        Amount: &jsapi.Amount{
            Total: core.Int64(total),
        },
        Payer: &jsapi.Payer{
            Openid: core.String(openid),
        },
    })
    if err != nil {
        return "", err
    }
    if resp == nil || resp.PrepayId == nil {
        return "", errors.New("missing prepay_id in response")
    }
    return *resp.PrepayId, nil
}

// RefundOrder 直连商户退款
// 入参：outTradeNo(商户订单号)、refundNo(商户退款单号)、amountRefund(退款金额分)、total(原订单金额分)、reason(退款原因，可空)
// 返回：微信退款单ID与状态，或错误
func (c *WechatPayClient) RefundOrder(ctx context.Context, outTradeNo, refundNo string, amountRefund, total int64, reason string) (string, string, error) {
    svc := refundsvc.RefundsApiService{Client: c.client}
    req := refundsvc.CreateRequest{
        OutTradeNo: core.String(outTradeNo),
        OutRefundNo: core.String(refundNo),
        Amount: &refundsvc.AmountReq{
            Refund: core.Int64(amountRefund),
            Total: core.Int64(total),
            Currency: core.String("CNY"),
        },
    }
    if reason != "" {
        req.Reason = core.String(reason)
    }
    resp, _, err := svc.Create(ctx, req)
    if err != nil {
        return "", "", err
    }
    var refundID, status string
    if resp != nil {
        if resp.RefundId != nil {
            refundID = *resp.RefundId
        }
        if resp.Status != nil {
            status = string(*resp.Status)
        }
    }
    if refundID == "" {
        return "", status, errors.New("missing refund_id in response")
    }
    return refundID, status, nil
}