monetix gateway

api/gateway/mntx/internal/service/gateway/callback.go

@@ -0,0 +1,134 @@
+package gateway
+
+import (
+	"context"
+	"crypto/hmac"
+	"net/http"
+	"strings"
+
+	"github.com/tech/sendico/gateway/mntx/internal/service/monetix"
+	clockpkg "github.com/tech/sendico/pkg/clock"
+	"github.com/tech/sendico/pkg/merrors"
+	mntxv1 "github.com/tech/sendico/pkg/proto/gateway/mntx/v1"
+	"google.golang.org/protobuf/types/known/timestamppb"
+)
+
+type callbackPayment struct {
+	ID          string `json:"id"`
+	Type        string `json:"type"`
+	Status      string `json:"status"`
+	Date        string `json:"date"`
+	Method      string `json:"method"`
+	Description string `json:"description"`
+	Sum         struct {
+		Amount   int64  `json:"amount"`
+		Currency string `json:"currency"`
+	} `json:"sum"`
+}
+
+type callbackOperation struct {
+	ID          int64  `json:"id"`
+	Type        string `json:"type"`
+	Status      string `json:"status"`
+	Date        string `json:"date"`
+	CreatedDate string `json:"created_date"`
+	RequestID   string `json:"request_id"`
+	SumInitial  struct {
+		Amount   int64  `json:"amount"`
+		Currency string `json:"currency"`
+	} `json:"sum_initial"`
+	SumConverted struct {
+		Amount   int64  `json:"amount"`
+		Currency string `json:"currency"`
+	} `json:"sum_converted"`
+	Provider struct {
+		ID        int64  `json:"id"`
+		PaymentID string `json:"payment_id"`
+		Date      string `json:"date"`
+		AuthCode  string `json:"auth_code"`
+	} `json:"provider"`
+	Code    string `json:"code"`
+	Message string `json:"message"`
+}
+
+type monetixCallback struct {
+	ProjectID int64           `json:"project_id"`
+	Payment   callbackPayment `json:"payment"`
+	Account   struct {
+		Number string `json:"number"`
+	} `json:"account"`
+	Customer struct {
+		ID string `json:"id"`
+	} `json:"customer"`
+	Operation callbackOperation `json:"operation"`
+	Signature string            `json:"signature"`
+}
+
+// ProcessMonetixCallback ingests Monetix provider callbacks and updates payout state.
+func (s *Service) ProcessMonetixCallback(ctx context.Context, payload []byte) (int, error) {
+	if s.card == nil {
+		return http.StatusInternalServerError, merrors.Internal("card payout processor not initialised")
+	}
+	return s.card.ProcessCallback(ctx, payload)
+}
+
+func mapCallbackToState(clock clockpkg.Clock, cfg monetix.Config, cb monetixCallback) (*mntxv1.CardPayoutState, string) {
+	status := strings.ToLower(strings.TrimSpace(cb.Payment.Status))
+	opStatus := strings.ToLower(strings.TrimSpace(cb.Operation.Status))
+	code := strings.TrimSpace(cb.Operation.Code)
+
+	outcome := monetix.OutcomeDecline
+	internalStatus := mntxv1.PayoutStatus_PAYOUT_STATUS_FAILED
+
+	if status == cfg.SuccessStatus() && opStatus == cfg.SuccessStatus() && (code == "" || code == "0") {
+		internalStatus = mntxv1.PayoutStatus_PAYOUT_STATUS_PROCESSED
+		outcome = monetix.OutcomeSuccess
+	} else if status == cfg.ProcessingStatus() || opStatus == cfg.ProcessingStatus() {
+		internalStatus = mntxv1.PayoutStatus_PAYOUT_STATUS_PENDING
+		outcome = monetix.OutcomeProcessing
+	}
+
+	now := timestamppb.New(clock.Now())
+	state := &mntxv1.CardPayoutState{
+		PayoutId:          cb.Payment.ID,
+		ProjectId:         cb.ProjectID,
+		CustomerId:        cb.Customer.ID,
+		AmountMinor:       cb.Payment.Sum.Amount,
+		Currency:          strings.ToUpper(strings.TrimSpace(cb.Payment.Sum.Currency)),
+		Status:            internalStatus,
+		ProviderCode:      cb.Operation.Code,
+		ProviderMessage:   cb.Operation.Message,
+		ProviderPaymentId: fallbackProviderPaymentID(cb),
+		UpdatedAt:         now,
+		CreatedAt:         now,
+	}
+
+	return state, outcome
+}
+
+func fallbackProviderPaymentID(cb monetixCallback) string {
+	if cb.Operation.Provider.PaymentID != "" {
+		return cb.Operation.Provider.PaymentID
+	}
+	if cb.Operation.RequestID != "" {
+		return cb.Operation.RequestID
+	}
+	return cb.Payment.ID
+}
+
+func verifyCallbackSignature(cb monetixCallback, secret string) error {
+	expected := cb.Signature
+	cb.Signature = ""
+	calculated, err := monetix.SignPayload(cb, secret)
+	if err != nil {
+		return err
+	}
+	if subtleConstantTimeCompare(expected, calculated) {
+		return nil
+	}
+	return merrors.DataConflict("signature mismatch")
+}
+
+func subtleConstantTimeCompare(a, b string) bool {
+	return hmac.Equal([]byte(strings.TrimSpace(a)), []byte(strings.TrimSpace(b)))
+}