unified gateway interfaces

api/server/interface/api/srequest/payment_intent.go

@@ -1,19 +1,22 @@
 package srequest
 
 import (
+	"strings"
+
 	"github.com/tech/sendico/pkg/merrors"
 	"github.com/tech/sendico/pkg/model"
 )
 
 type PaymentIntent struct {
-	Kind           PaymentKind       `json:"kind,omitempty"`
-	Source         *Endpoint         `json:"source,omitempty"`
-	Destination    *Endpoint         `json:"destination,omitempty"`
-	Amount         *model.Money      `json:"amount,omitempty"`
-	FX             *FXIntent         `json:"fx,omitempty"`
-	SettlementMode SettlementMode    `json:"settlement_mode,omitempty"`
-	Attributes     map[string]string `json:"attributes,omitempty"`
-	Customer       *Customer         `json:"customer,omitempty"`
+	Kind               PaymentKind       `json:"kind,omitempty"`
+	Source             *Endpoint         `json:"source,omitempty"`
+	Destination        *Endpoint         `json:"destination,omitempty"`
+	Amount             *model.Money      `json:"amount,omitempty"`
+	FX                 *FXIntent         `json:"fx,omitempty"`
+	SettlementMode     SettlementMode    `json:"settlement_mode,omitempty"`
+	SettlementCurrency string            `json:"settlement_currency,omitempty"`
+	Attributes         map[string]string `json:"attributes,omitempty"`
+	Customer           *Customer         `json:"customer,omitempty"`
 }
 
 type AssetResolverStub struct{}
@@ -51,5 +54,11 @@ func (p *PaymentIntent) Validate() error {
 		}
 	}
 
+	if strings.TrimSpace(p.SettlementCurrency) != "" {
+		if err := ValidateCurrency(p.SettlementCurrency, &AssetResolverStub{}); err != nil {
+			return err
+		}
+	}
+
 	return nil
 }

api/server/internal/server/paymentapiimp/mapper.go

@@ -26,6 +26,10 @@ func mapPaymentIntent(intent *srequest.PaymentIntent) (*orchestratorv1.PaymentIn
 	if err != nil {
 		return nil, err
 	}
+	settlementCurrency := strings.TrimSpace(intent.SettlementCurrency)
+	if settlementCurrency == "" {
+		settlementCurrency = resolveSettlementCurrency(intent)
+	}
 
 	source, err := mapPaymentEndpoint(intent.Source, "source")
 	if err != nil {
@@ -42,18 +46,66 @@ func mapPaymentIntent(intent *srequest.PaymentIntent) (*orchestratorv1.PaymentIn
 	}
 
 	return &orchestratorv1.PaymentIntent{
-		Kind:           kind,
-		Source:         source,
-		Destination:    destination,
-		Amount:         mapMoney(intent.Amount),
-		RequiresFx:     fx != nil,
-		Fx:             fx,
-		SettlementMode: settlementMode,
-		Attributes:     copyStringMap(intent.Attributes),
-		Customer:       mapCustomer(intent.Customer),
+		Kind:               kind,
+		Source:             source,
+		Destination:        destination,
+		Amount:             mapMoney(intent.Amount),
+		RequiresFx:         fx != nil,
+		Fx:                 fx,
+		SettlementMode:     settlementMode,
+		SettlementCurrency: settlementCurrency,
+		Attributes:         copyStringMap(intent.Attributes),
+		Customer:           mapCustomer(intent.Customer),
 	}, nil
 }
 
+func resolveSettlementCurrency(intent *srequest.PaymentIntent) string {
+	if intent == nil {
+		return ""
+	}
+
+	fx := intent.FX
+	if fx != nil && fx.Pair != nil {
+		base := strings.TrimSpace(fx.Pair.Base)
+		quote := strings.TrimSpace(fx.Pair.Quote)
+		switch strings.TrimSpace(string(fx.Side)) {
+		case string(srequest.FXSideBuyBaseSellQuote):
+			if base != "" {
+				return base
+			}
+		case string(srequest.FXSideSellBaseBuyQuote):
+			if quote != "" {
+				return quote
+			}
+		}
+		if intent.Amount != nil {
+			amountCurrency := strings.TrimSpace(intent.Amount.Currency)
+			if amountCurrency != "" {
+				switch {
+				case strings.EqualFold(amountCurrency, base) && quote != "":
+					return quote
+				case strings.EqualFold(amountCurrency, quote) && base != "":
+					return base
+				default:
+					return amountCurrency
+				}
+			}
+		}
+		if quote != "" {
+			return quote
+		}
+		if base != "" {
+			return base
+		}
+	}
+
+	if intent.Amount != nil {
+		return strings.TrimSpace(intent.Amount.Currency)
+	}
+
+	return ""
+}
+
 func mapPaymentEndpoint(endpoint *srequest.Endpoint, field string) (*orchestratorv1.PaymentEndpoint, error) {
 	if endpoint == nil {
 		return nil, nil