Merge pull request 'improved logging + autotests' (#189) from mntx-188 into main

Reviewed-on: #189

api/gateway/chain/internal/service/gateway/commands/transfer/destination.go

@@ -17,21 +17,21 @@ func resolveDestination(ctx context.Context, deps Deps, dest *chainv1.TransferDe
 	managedRef := strings.TrimSpace(dest.GetManagedWalletRef())
 	external := strings.TrimSpace(dest.GetExternalAddress())
 	if managedRef != "" && external != "" {
-		deps.Logger.Warn("both managed and external destination provided")
+		deps.Logger.Warn("Both managed and external destination provided")
 		return model.TransferDestination{}, merrors.InvalidArgument("destination must be managed_wallet_ref or external_address")
 	}
 	if managedRef != "" {
 		wallet, err := deps.Storage.Wallets().Get(ctx, managedRef)
 		if err != nil {
-			deps.Logger.Warn("destination wallet lookup failed", zap.Error(err), zap.String("managed_wallet_ref", managedRef))
+			deps.Logger.Warn("Destination wallet lookup failed", zap.Error(err), zap.String("managed_wallet_ref", managedRef))
 			return model.TransferDestination{}, err
 		}
 		if !strings.EqualFold(wallet.Network, source.Network) {
-			deps.Logger.Warn("destination wallet network mismatch", zap.String("source_network", source.Network), zap.String("dest_network", wallet.Network))
+			deps.Logger.Warn("Destination wallet network mismatch", zap.String("source_network", source.Network), zap.String("dest_network", wallet.Network))
 			return model.TransferDestination{}, merrors.InvalidArgument("destination wallet network mismatch")
 		}
 		if strings.TrimSpace(wallet.DepositAddress) == "" {
-			deps.Logger.Warn("destination wallet missing deposit address", zap.String("managed_wallet_ref", managedRef))
+			deps.Logger.Warn("Destination wallet missing deposit address", zap.String("managed_wallet_ref", managedRef))
 			return model.TransferDestination{}, merrors.InvalidArgument("destination wallet missing deposit address")
 		}
 		return model.TransferDestination{
@@ -40,21 +40,21 @@ func resolveDestination(ctx context.Context, deps Deps, dest *chainv1.TransferDe
 		}, nil
 	}
 	if external == "" {
-		deps.Logger.Warn("destination external address missing")
+		deps.Logger.Warn("Destination external address missing")
 		return model.TransferDestination{}, merrors.InvalidArgument("destination is required")
 	}
 	if deps.Drivers == nil {
-		deps.Logger.Warn("chain drivers missing", zap.String("network", source.Network))
+		deps.Logger.Warn("Chain drivers missing", zap.String("network", source.Network))
 		return model.TransferDestination{}, merrors.Internal("chain drivers not configured")
 	}
 	chainDriver, err := deps.Drivers.Driver(source.Network)
 	if err != nil {
-		deps.Logger.Warn("unsupported chain driver", zap.String("network", source.Network), zap.Error(err))
+		deps.Logger.Warn("Unsupported chain driver", zap.String("network", source.Network), zap.Error(err))
 		return model.TransferDestination{}, merrors.InvalidArgument("unsupported chain for wallet")
 	}
 	normalized, err := chainDriver.NormalizeAddress(external)
 	if err != nil {
-		deps.Logger.Warn("invalid external address", zap.Error(err))
+		deps.Logger.Warn("Invalid external address", zap.Error(err))
 		return model.TransferDestination{}, err
 	}
 	return model.TransferDestination{

api/gateway/chain/internal/service/gateway/commands/transfer/fee.go

@@ -6,6 +6,7 @@ import (
 	"strings"
 
 	"github.com/tech/sendico/gateway/chain/internal/service/gateway/driver"
+	"github.com/tech/sendico/gateway/chain/internal/service/gateway/shared"
 	"github.com/tech/sendico/pkg/api/routers/gsresponse"
 	"github.com/tech/sendico/pkg/merrors"
 	"github.com/tech/sendico/pkg/mservice"
@@ -23,11 +24,11 @@ func NewEstimateTransfer(deps Deps) *estimateTransferFeeCommand {
 
 func (c *estimateTransferFeeCommand) Execute(ctx context.Context, req *chainv1.EstimateTransferFeeRequest) gsresponse.Responder[chainv1.EstimateTransferFeeResponse] {
 	if err := c.deps.EnsureRepository(ctx); err != nil {
-		c.deps.Logger.Warn("repository unavailable", zap.Error(err))
+		c.deps.Logger.Warn("Repository unavailable", zap.Error(err))
 		return gsresponse.Unavailable[chainv1.EstimateTransferFeeResponse](c.deps.Logger, mservice.ChainGateway, err)
 	}
 	if req == nil {
-		c.deps.Logger.Warn("nil request")
+		c.deps.Logger.Warn("Empty request received")
 		return gsresponse.InvalidArgument[chainv1.EstimateTransferFeeResponse](c.deps.Logger, mservice.ChainGateway, merrors.InvalidArgument("request is required"))
 	}
 
@@ -45,58 +46,67 @@ func (c *estimateTransferFeeCommand) Execute(ctx context.Context, req *chainv1.E
 	sourceWallet, err := c.deps.Storage.Wallets().Get(ctx, sourceWalletRef)
 	if err != nil {
 		if errors.Is(err, merrors.ErrNoData) {
-			c.deps.Logger.Warn("source wallet not found", zap.String("source_wallet_ref", sourceWalletRef))
+			c.deps.Logger.Warn("Source wallet not found", zap.String("source_wallet_ref", sourceWalletRef))
 			return gsresponse.NotFound[chainv1.EstimateTransferFeeResponse](c.deps.Logger, mservice.ChainGateway, err)
 		}
-		c.deps.Logger.Warn("storage get wallet failed", zap.Error(err), zap.String("source_wallet_ref", sourceWalletRef))
+		c.deps.Logger.Warn("Storage get wallet failed", zap.Error(err), zap.String("source_wallet_ref", sourceWalletRef))
 		return gsresponse.Auto[chainv1.EstimateTransferFeeResponse](c.deps.Logger, mservice.ChainGateway, err)
 	}
 
 	networkKey := strings.ToLower(strings.TrimSpace(sourceWallet.Network))
 	networkCfg, ok := c.deps.Networks.Network(networkKey)
 	if !ok {
-		c.deps.Logger.Warn("unsupported chain", zap.String("network", networkKey))
+		c.deps.Logger.Warn("Unsupported chain", zap.String("network", networkKey))
 		return gsresponse.InvalidArgument[chainv1.EstimateTransferFeeResponse](c.deps.Logger, mservice.ChainGateway, merrors.InvalidArgument("unsupported chain for wallet"))
 	}
 	if c.deps.Drivers == nil {
-		c.deps.Logger.Warn("chain drivers missing", zap.String("network", networkKey))
+		c.deps.Logger.Warn("Chain drivers missing", zap.String("network", networkKey))
 		return gsresponse.Internal[chainv1.EstimateTransferFeeResponse](c.deps.Logger, mservice.ChainGateway, merrors.Internal("chain drivers not configured"))
 	}
 	chainDriver, err := c.deps.Drivers.Driver(networkKey)
 	if err != nil {
-		c.deps.Logger.Warn("unsupported chain driver", zap.String("network", networkKey), zap.Error(err))
+		c.deps.Logger.Warn("Unsupported chain driver", zap.String("network", networkKey), zap.Error(err))
 		return gsresponse.InvalidArgument[chainv1.EstimateTransferFeeResponse](c.deps.Logger, mservice.ChainGateway, merrors.InvalidArgument("unsupported chain for wallet"))
 	}
 
 	dest, err := resolveDestination(ctx, c.deps, req.GetDestination(), sourceWallet)
 	if err != nil {
 		if errors.Is(err, merrors.ErrNoData) {
-			c.deps.Logger.Warn("destination not found", zap.String("destination_wallet_ref", req.GetDestination().GetManagedWalletRef()))
+			c.deps.Logger.Warn("Destination not found", zap.String("destination_wallet_ref", req.GetDestination().GetManagedWalletRef()))
 			return gsresponse.NotFound[chainv1.EstimateTransferFeeResponse](c.deps.Logger, mservice.ChainGateway, err)
 		}
-		c.deps.Logger.Warn("invalid destination", zap.Error(err))
+		c.deps.Logger.Warn("Invalid destination", zap.Error(err))
 		return gsresponse.InvalidArgument[chainv1.EstimateTransferFeeResponse](c.deps.Logger, mservice.ChainGateway, err)
 	}
 
 	destinationAddress, err := destinationAddress(ctx, c.deps, chainDriver, dest)
 	if err != nil {
-		c.deps.Logger.Warn("failed to resolve destination address", zap.Error(err))
+		c.deps.Logger.Warn("Failed to resolve destination address", zap.Error(err))
 		return gsresponse.InvalidArgument[chainv1.EstimateTransferFeeResponse](c.deps.Logger, mservice.ChainGateway, err)
 	}
 
+	walletForFee := sourceWallet
+	nativeCurrency := shared.NativeCurrency(networkCfg)
+	if nativeCurrency != "" && strings.EqualFold(nativeCurrency, amount.GetCurrency()) {
+		copyWallet := *sourceWallet
+		copyWallet.ContractAddress = ""
+		copyWallet.TokenSymbol = nativeCurrency
+		walletForFee = &copyWallet
+	}
+
 	driverDeps := driver.Deps{
 		Logger:     c.deps.Logger,
 		Registry:   c.deps.Networks,
 		RPCTimeout: c.deps.RPCTimeout,
 	}
-	feeMoney, err := chainDriver.EstimateFee(ctx, driverDeps, networkCfg, sourceWallet, destinationAddress, amount)
+	feeMoney, err := chainDriver.EstimateFee(ctx, driverDeps, networkCfg, walletForFee, destinationAddress, amount)
 	if err != nil {
-		c.deps.Logger.Warn("fee estimation failed", zap.Error(err))
+		c.deps.Logger.Warn("Fee estimation failed", zap.Error(err))
 		return gsresponse.Auto[chainv1.EstimateTransferFeeResponse](c.deps.Logger, mservice.ChainGateway, err)
 	}
 
 	contextLabel := "erc20_transfer"
-	if strings.TrimSpace(sourceWallet.ContractAddress) == "" {
+	if strings.TrimSpace(walletForFee.ContractAddress) == "" {
 		contextLabel = "native_transfer"
 	}
 	resp := &chainv1.EstimateTransferFeeResponse{

api/gateway/chain/internal/service/gateway/commands/transfer/submit.go

@@ -25,7 +25,7 @@ func NewSubmitTransfer(deps Deps) *submitTransferCommand {
 
 func (c *submitTransferCommand) Execute(ctx context.Context, req *chainv1.SubmitTransferRequest) gsresponse.Responder[chainv1.SubmitTransferResponse] {
 	if err := c.deps.EnsureRepository(ctx); err != nil {
-		c.deps.Logger.Warn("repository unavailable", zap.Error(err))
+		c.deps.Logger.Warn("Repository unavailable", zap.Error(err))
 		return gsresponse.Unavailable[chainv1.SubmitTransferResponse](c.deps.Logger, mservice.ChainGateway, err)
 	}
 	if req == nil {
@@ -35,84 +35,92 @@ func (c *submitTransferCommand) Execute(ctx context.Context, req *chainv1.Submit
 
 	idempotencyKey := strings.TrimSpace(req.GetIdempotencyKey())
 	if idempotencyKey == "" {
-		c.deps.Logger.Warn("missing idempotency key")
+		c.deps.Logger.Warn("Missing idempotency key")
 		return gsresponse.InvalidArgument[chainv1.SubmitTransferResponse](c.deps.Logger, mservice.ChainGateway, merrors.InvalidArgument("idempotency_key is required"))
 	}
 	organizationRef := strings.TrimSpace(req.GetOrganizationRef())
 	if organizationRef == "" {
-		c.deps.Logger.Warn("missing organization ref")
+		c.deps.Logger.Warn("mMssing organization ref")
 		return gsresponse.InvalidArgument[chainv1.SubmitTransferResponse](c.deps.Logger, mservice.ChainGateway, merrors.InvalidArgument("organization_ref is required"))
 	}
 	sourceWalletRef := strings.TrimSpace(req.GetSourceWalletRef())
 	if sourceWalletRef == "" {
-		c.deps.Logger.Warn("missing source wallet ref")
+		c.deps.Logger.Warn("Missing source wallet ref")
 		return gsresponse.InvalidArgument[chainv1.SubmitTransferResponse](c.deps.Logger, mservice.ChainGateway, merrors.InvalidArgument("source_wallet_ref is required"))
 	}
 	amount := req.GetAmount()
 	if amount == nil {
-		c.deps.Logger.Warn("missing amount")
+		c.deps.Logger.Warn("Missing amount")
 		return gsresponse.InvalidArgument[chainv1.SubmitTransferResponse](c.deps.Logger, mservice.ChainGateway, merrors.InvalidArgument("amount is required"))
 	}
 	amountCurrency := strings.ToUpper(strings.TrimSpace(amount.GetCurrency()))
 	if amountCurrency == "" {
-		c.deps.Logger.Warn("missing amount currency")
+		c.deps.Logger.Warn("Missing amount currency")
 		return gsresponse.InvalidArgument[chainv1.SubmitTransferResponse](c.deps.Logger, mservice.ChainGateway, merrors.InvalidArgument("amount.currency is required"))
 	}
 	amountValue := strings.TrimSpace(amount.GetAmount())
 	if amountValue == "" {
-		c.deps.Logger.Warn("missing amount value")
+		c.deps.Logger.Warn("Missing amount value")
 		return gsresponse.InvalidArgument[chainv1.SubmitTransferResponse](c.deps.Logger, mservice.ChainGateway, merrors.InvalidArgument("amount.amount is required"))
 	}
 
 	sourceWallet, err := c.deps.Storage.Wallets().Get(ctx, sourceWalletRef)
 	if err != nil {
 		if errors.Is(err, merrors.ErrNoData) {
-			c.deps.Logger.Warn("source wallet not found", zap.String("source_wallet_ref", sourceWalletRef))
+			c.deps.Logger.Warn("Source wallet not found", zap.String("source_wallet_ref", sourceWalletRef))
 			return gsresponse.NotFound[chainv1.SubmitTransferResponse](c.deps.Logger, mservice.ChainGateway, err)
 		}
-		c.deps.Logger.Warn("storage get wallet failed", zap.Error(err), zap.String("source_wallet_ref", sourceWalletRef))
+		c.deps.Logger.Warn("Storage get wallet failed", zap.Error(err), zap.String("source_wallet_ref", sourceWalletRef))
 		return gsresponse.Auto[chainv1.SubmitTransferResponse](c.deps.Logger, mservice.ChainGateway, err)
 	}
 	if !strings.EqualFold(sourceWallet.OrganizationRef, organizationRef) {
-		c.deps.Logger.Warn("organization mismatch", zap.String("wallet_org", sourceWallet.OrganizationRef), zap.String("req_org", organizationRef))
+		c.deps.Logger.Warn("Organization mismatch", zap.String("wallet_org", sourceWallet.OrganizationRef), zap.String("req_org", organizationRef))
 		return gsresponse.InvalidArgument[chainv1.SubmitTransferResponse](c.deps.Logger, mservice.ChainGateway, merrors.InvalidArgument("organization_ref mismatch with wallet"))
 	}
 	networkKey := strings.ToLower(strings.TrimSpace(sourceWallet.Network))
 	networkCfg, ok := c.deps.Networks.Network(networkKey)
 	if !ok {
-		c.deps.Logger.Warn("unsupported chain", zap.String("network", networkKey))
+		c.deps.Logger.Warn("Unsupported chain", zap.String("network", networkKey))
 		return gsresponse.InvalidArgument[chainv1.SubmitTransferResponse](c.deps.Logger, mservice.ChainGateway, merrors.InvalidArgument("unsupported chain for wallet"))
 	}
 
 	destination, err := resolveDestination(ctx, c.deps, req.GetDestination(), sourceWallet)
 	if err != nil {
 		if errors.Is(err, merrors.ErrNoData) {
-			c.deps.Logger.Warn("destination not found", zap.String("destination_wallet_ref", req.GetDestination().GetManagedWalletRef()))
+			c.deps.Logger.Warn("Destination not found", zap.String("destination_wallet_ref", req.GetDestination().GetManagedWalletRef()))
 			return gsresponse.NotFound[chainv1.SubmitTransferResponse](c.deps.Logger, mservice.ChainGateway, err)
 		}
-		c.deps.Logger.Warn("invalid destination", zap.Error(err))
+		c.deps.Logger.Warn("Invalid destination", zap.Error(err))
 		return gsresponse.InvalidArgument[chainv1.SubmitTransferResponse](c.deps.Logger, mservice.ChainGateway, err)
 	}
 
 	fees, feeSum, err := convertFees(req.GetFees(), amountCurrency)
 	if err != nil {
-		c.deps.Logger.Warn("fee conversion failed", zap.Error(err))
+		c.deps.Logger.Warn("Fee conversion failed", zap.Error(err))
 		return gsresponse.InvalidArgument[chainv1.SubmitTransferResponse](c.deps.Logger, mservice.ChainGateway, err)
 	}
 	amountDec, err := decimal.NewFromString(amountValue)
 	if err != nil {
-		c.deps.Logger.Warn("invalid amount", zap.Error(err))
+		c.deps.Logger.Warn("Invalid amount", zap.Error(err))
 		return gsresponse.InvalidArgument[chainv1.SubmitTransferResponse](c.deps.Logger, mservice.ChainGateway, merrors.InvalidArgument("invalid amount"))
 	}
 	netDec := amountDec.Sub(feeSum)
 	if netDec.IsNegative() {
-		c.deps.Logger.Warn("fees exceed amount", zap.String("amount", amountValue), zap.String("fee_sum", feeSum.String()))
+		c.deps.Logger.Warn("Fees exceed amount", zap.String("amount", amountValue), zap.String("fee_sum", feeSum.String()))
 		return gsresponse.InvalidArgument[chainv1.SubmitTransferResponse](c.deps.Logger, mservice.ChainGateway, merrors.InvalidArgument("fees exceed amount"))
 	}
 
 	netAmount := shared.CloneMoney(amount)
 	netAmount.Amount = netDec.String()
 
+	effectiveTokenSymbol := sourceWallet.TokenSymbol
+	effectiveContractAddress := sourceWallet.ContractAddress
+	nativeCurrency := shared.NativeCurrency(networkCfg)
+	if nativeCurrency != "" && strings.EqualFold(nativeCurrency, amountCurrency) {
+		effectiveTokenSymbol = nativeCurrency
+		effectiveContractAddress = ""
+	}
+
 	transfer := &model.Transfer{
 		IdempotencyKey:  idempotencyKey,
 		TransferRef:     shared.GenerateTransferRef(),
@@ -120,8 +128,8 @@ func (c *submitTransferCommand) Execute(ctx context.Context, req *chainv1.Submit
 		SourceWalletRef: sourceWalletRef,
 		Destination:     destination,
 		Network:         sourceWallet.Network,
-		TokenSymbol:     sourceWallet.TokenSymbol,
-		ContractAddress: sourceWallet.ContractAddress,
+		TokenSymbol:     effectiveTokenSymbol,
+		ContractAddress: effectiveContractAddress,
 		RequestedAmount: shared.CloneMoney(amount),
 		NetAmount:       netAmount,
 		Fees:            fees,
@@ -133,10 +141,10 @@ func (c *submitTransferCommand) Execute(ctx context.Context, req *chainv1.Submit
 	saved, err := c.deps.Storage.Transfers().Create(ctx, transfer)
 	if err != nil {
 		if errors.Is(err, merrors.ErrDataConflict) {
-			c.deps.Logger.Debug("transfer already exists", zap.String("transfer_ref", transfer.TransferRef), zap.String("idempotency_key", idempotencyKey))
+			c.deps.Logger.Debug("Transfer already exists", zap.String("transfer_ref", transfer.TransferRef), zap.String("idempotency_key", idempotencyKey))
 			return gsresponse.Success(&chainv1.SubmitTransferResponse{Transfer: toProtoTransfer(saved)})
 		}
-		c.deps.Logger.Warn("storage create failed", zap.Error(err), zap.String("transfer_ref", transfer.TransferRef))
+		c.deps.Logger.Warn("Storage create failed", zap.Error(err), zap.String("transfer_ref", transfer.TransferRef))
 		return gsresponse.Auto[chainv1.SubmitTransferResponse](c.deps.Logger, mservice.ChainGateway, err)
 	}
 

api/gateway/chain/internal/service/gateway/driver/arbitrum/driver.go

@@ -95,7 +95,7 @@ func (d *Driver) NativeBalance(ctx context.Context, deps driver.Deps, network sh
 }
 
 func (d *Driver) EstimateFee(ctx context.Context, deps driver.Deps, network shared.Network, wallet *model.ManagedWallet, destination string, amount *moneyv1.Money) (*moneyv1.Money, error) {
-	d.logger.Debug("estimate fee request",
+	d.logger.Debug("Estimate fee request",
 		zap.String("wallet_ref", wallet.WalletRef),
 		zap.String("network", network.Name),
 		zap.String("destination", destination),
@@ -104,13 +104,13 @@ func (d *Driver) EstimateFee(ctx context.Context, deps driver.Deps, network shar
 	driverDeps.Logger = d.logger
 	result, err := evm.EstimateFee(ctx, driverDeps, network, wallet, wallet.DepositAddress, destination, amount)
 	if err != nil {
-		d.logger.Warn("estimate fee failed",
+		d.logger.Warn("Estimate fee failed",
 			zap.String("wallet_ref", wallet.WalletRef),
 			zap.String("network", network.Name),
 			zap.Error(err),
 		)
 	} else if result != nil {
-		d.logger.Debug("estimate fee result",
+		d.logger.Debug("Estimate fee result",
 			zap.String("wallet_ref", wallet.WalletRef),
 			zap.String("network", network.Name),
 			zap.String("amount", result.Amount),

api/gateway/chain/internal/service/gateway/driver/ethereum/driver.go

@@ -95,7 +95,7 @@ func (d *Driver) NativeBalance(ctx context.Context, deps driver.Deps, network sh
 }
 
 func (d *Driver) EstimateFee(ctx context.Context, deps driver.Deps, network shared.Network, wallet *model.ManagedWallet, destination string, amount *moneyv1.Money) (*moneyv1.Money, error) {
-	d.logger.Debug("estimate fee request",
+	d.logger.Debug("Estimate fee request",
 		zap.String("wallet_ref", wallet.WalletRef),
 		zap.String("network", network.Name),
 		zap.String("destination", destination),
@@ -104,13 +104,13 @@ func (d *Driver) EstimateFee(ctx context.Context, deps driver.Deps, network shar
 	driverDeps.Logger = d.logger
 	result, err := evm.EstimateFee(ctx, driverDeps, network, wallet, wallet.DepositAddress, destination, amount)
 	if err != nil {
-		d.logger.Warn("estimate fee failed",
+		d.logger.Warn("Estimate fee failed",
 			zap.String("wallet_ref", wallet.WalletRef),
 			zap.String("network", network.Name),
 			zap.Error(err),
 		)
 	} else if result != nil {
-		d.logger.Debug("estimate fee result",
+		d.logger.Debug("Estimate fee result",
 			zap.String("wallet_ref", wallet.WalletRef),
 			zap.String("network", network.Name),
 			zap.String("amount", result.Amount),

api/gateway/chain/internal/service/gateway/driver/evm/estimate_gas_test.go

@@ -0,0 +1,31 @@
+package evm
+
+import (
+	"math/big"
+	"strings"
+	"testing"
+
+	"github.com/ethereum/go-ethereum"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/stretchr/testify/require"
+)
+
+func TestTronEstimateCallUsesData(t *testing.T) {
+	from := common.HexToAddress("0xfa89b4d534bdeb2713d4ffd893e79d6535fb58f8")
+	to := common.HexToAddress("0xa614f803b6fd780986a42c78ec9c7f77e6ded13c")
+	callMsg := ethereum.CallMsg{
+		From:     from,
+		To:       &to,
+		GasPrice: big.NewInt(100),
+		Data:     []byte{0xa9, 0x05, 0x9c, 0xbb},
+	}
+
+	call := tronEstimateCall(callMsg)
+
+	require.Equal(t, strings.ToLower(from.Hex()), call["from"])
+	require.Equal(t, strings.ToLower(to.Hex()), call["to"])
+	require.Equal(t, "0x64", call["gasPrice"])
+	require.Equal(t, "0xa9059cbb", call["data"])
+	_, hasInput := call["input"]
+	require.False(t, hasInput)
+}

api/gateway/chain/internal/service/gateway/driver/evm/evm.go

@@ -10,6 +10,7 @@ import (
 	"github.com/ethereum/go-ethereum"
 	"github.com/ethereum/go-ethereum/accounts/abi"
 	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/common/hexutil"
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/ethereum/go-ethereum/rpc"
 	"github.com/shopspring/decimal"
@@ -95,7 +96,7 @@ func parseBaseUnitAmount(amount string) (*big.Int, error) {
 
 // Balance fetches ERC20 token balance for the provided address.
 func Balance(ctx context.Context, deps driver.Deps, network shared.Network, wallet *model.ManagedWallet, address string) (*moneyv1.Money, error) {
-	logger := deps.Logger
+	logger := deps.Logger.Named("evm")
 	registry := deps.Registry
 
 	if registry == nil {
@@ -175,7 +176,7 @@ func Balance(ctx context.Context, deps driver.Deps, network shared.Network, wall
 
 // NativeBalance fetches native token balance for the provided address.
 func NativeBalance(ctx context.Context, deps driver.Deps, network shared.Network, wallet *model.ManagedWallet, address string) (*moneyv1.Money, error) {
-	logger := deps.Logger
+	logger := deps.Logger.Named("evm")
 	registry := deps.Registry
 
 	if registry == nil {
@@ -233,7 +234,7 @@ func NativeBalance(ctx context.Context, deps driver.Deps, network shared.Network
 
 // EstimateFee estimates ERC20 transfer fees for the given parameters.
 func EstimateFee(ctx context.Context, deps driver.Deps, network shared.Network, wallet *model.ManagedWallet, fromAddress, destination string, amount *moneyv1.Money) (*moneyv1.Money, error) {
-	logger := deps.Logger
+	logger := deps.Logger.Named("evm")
 	registry := deps.Registry
 
 	if registry == nil {
@@ -259,10 +260,12 @@ func EstimateFee(ctx context.Context, deps driver.Deps, network shared.Network,
 
 	client, err := registry.Client(network.Name)
 	if err != nil {
+		logger.Warn("Failed to resolve client", zap.Error(err), zap.String("network_name", network.Name))
 		return nil, err
 	}
 	rpcClient, err := registry.RPCClient(network.Name)
 	if err != nil {
+		logger.Warn("Failed to resolve RPC client", zap.Error(err), zap.String("network_name", network.Name))
 		return nil, err
 	}
 
@@ -280,10 +283,12 @@ func EstimateFee(ctx context.Context, deps driver.Deps, network shared.Network,
 	if contract == "" {
 		amountBase, err := parseBaseUnitAmount(amount.GetAmount())
 		if err != nil {
+			logger.Warn("Failed to parse base unit amount", zap.Error(err), zap.String("amount", amount.GetAmount()))
 			return nil, err
 		}
 		gasPrice, err := client.SuggestGasPrice(timeoutCtx)
 		if err != nil {
+			logger.Warn("Failed to suggest gas price", zap.Error(err))
 			return nil, merrors.Internal("failed to suggest gas price: " + err.Error())
 		}
 		callMsg := ethereum.CallMsg{
@@ -292,8 +297,9 @@ func EstimateFee(ctx context.Context, deps driver.Deps, network shared.Network,
 			GasPrice: gasPrice,
 			Value:    amountBase,
 		}
-		gasLimit, err := client.EstimateGas(timeoutCtx, callMsg)
+		gasLimit, err := estimateGas(timeoutCtx, network, client, rpcClient, callMsg)
 		if err != nil {
+			logger.Warn("Failed to estimate gas", zap.Error(err), zap.Any("call_mesasge", callMsg))
 			return nil, merrors.Internal("failed to estimate gas: " + err.Error())
 		}
 		fee := new(big.Int).Mul(gasPrice, new(big.Int).SetUint64(gasLimit))
@@ -304,6 +310,7 @@ func EstimateFee(ctx context.Context, deps driver.Deps, network shared.Network,
 		}, nil
 	}
 	if !common.IsHexAddress(contract) {
+		logger.Warn("Failed to validate contract", zap.String("contract", contract))
 		return nil, merrors.InvalidArgument("invalid token contract address")
 	}
 
@@ -322,11 +329,13 @@ func EstimateFee(ctx context.Context, deps driver.Deps, network shared.Network,
 
 	input, err := erc20ABI.Pack("transfer", toAddr, amountBase)
 	if err != nil {
+		logger.Warn("Failed to encode transfer call", zap.Error(err))
 		return nil, merrors.Internal("failed to encode transfer call: " + err.Error())
 	}
 
 	gasPrice, err := client.SuggestGasPrice(timeoutCtx)
 	if err != nil {
+		logger.Warn("Failed to suggest gas price", zap.Error(err))
 		return nil, merrors.Internal("failed to suggest gas price: " + err.Error())
 	}
 
@@ -336,8 +345,9 @@ func EstimateFee(ctx context.Context, deps driver.Deps, network shared.Network,
 		GasPrice: gasPrice,
 		Data:     input,
 	}
-	gasLimit, err := client.EstimateGas(timeoutCtx, callMsg)
+	gasLimit, err := estimateGas(timeoutCtx, network, client, rpcClient, callMsg)
 	if err != nil {
+		logger.Warn("Failed to estimate gas", zap.Error(err), zap.Any("call_message", callMsg))
 		return nil, merrors.Internal("failed to estimate gas: " + err.Error())
 	}
 
@@ -352,7 +362,7 @@ func EstimateFee(ctx context.Context, deps driver.Deps, network shared.Network,
 
 // SubmitTransfer submits an ERC20 transfer on an EVM-compatible chain.
 func SubmitTransfer(ctx context.Context, deps driver.Deps, network shared.Network, transfer *model.Transfer, source *model.ManagedWallet, fromAddress, destination string) (string, error) {
-	logger := deps.Logger
+	logger := deps.Logger.Named("evm")
 	registry := deps.Registry
 
 	if deps.KeyManager == nil {
@@ -384,7 +394,7 @@ func SubmitTransfer(ctx context.Context, deps driver.Deps, network shared.Networ
 		return "", executorInvalid("invalid destination address " + destination)
 	}
 
-	logger.Info("submitting transfer",
+	logger.Info("Submitting transfer",
 		zap.String("transfer_ref", transfer.TransferRef),
 		zap.String("source_wallet_ref", source.WalletRef),
 		zap.String("network", network.Name),
@@ -393,12 +403,12 @@ func SubmitTransfer(ctx context.Context, deps driver.Deps, network shared.Networ
 
 	client, err := registry.Client(network.Name)
 	if err != nil {
-		logger.Warn("Failed to initialise rpc client", zap.Error(err), zap.String("network", network.Name))
+		logger.Warn("Failed to initialise RPC client", zap.Error(err), zap.String("network", network.Name))
 		return "", err
 	}
 	rpcClient, err := registry.RPCClient(network.Name)
 	if err != nil {
-		logger.Warn("failed to initialise rpc client", zap.String("network", network.Name))
+		logger.Warn("Failed to initialise RPC client", zap.String("network", network.Name))
 		return "", err
 	}
 
@@ -448,7 +458,7 @@ func SubmitTransfer(ctx context.Context, deps driver.Deps, network shared.Networ
 			GasPrice: gasPrice,
 			Value:    amountInt,
 		}
-		gasLimit, err := client.EstimateGas(ctx, callMsg)
+		gasLimit, err := estimateGas(ctx, network, client, rpcClient, callMsg)
 		if err != nil {
 			logger.Warn("Failed to estimate gas", zap.Error(err),
 				zap.String("transfer_ref", transfer.TransferRef),
@@ -498,7 +508,7 @@ func SubmitTransfer(ctx context.Context, deps driver.Deps, network shared.Networ
 			GasPrice: gasPrice,
 			Data:     input,
 		}
-		gasLimit, err := client.EstimateGas(ctx, callMsg)
+		gasLimit, err := estimateGas(ctx, network, client, rpcClient, callMsg)
 		if err != nil {
 			logger.Warn("Failed to estimate gas", zap.Error(err),
 				zap.String("transfer_ref", transfer.TransferRef),
@@ -537,7 +547,7 @@ func SubmitTransfer(ctx context.Context, deps driver.Deps, network shared.Networ
 
 // AwaitConfirmation waits for the transaction receipt.
 func AwaitConfirmation(ctx context.Context, deps driver.Deps, network shared.Network, txHash string) (*types.Receipt, error) {
-	logger := deps.Logger
+	logger := deps.Logger.Named("evm")
 	registry := deps.Registry
 
 	if strings.TrimSpace(txHash) == "" {
@@ -652,6 +662,63 @@ func erc20Decimals(ctx context.Context, client *rpc.Client, token common.Address
 	return val, nil
 }
 
+type gasEstimator interface {
+	EstimateGas(ctx context.Context, msg ethereum.CallMsg) (uint64, error)
+}
+
+func estimateGas(ctx context.Context, network shared.Network, client gasEstimator, rpcClient *rpc.Client, callMsg ethereum.CallMsg) (uint64, error) {
+	if isTronNetwork(network) {
+		if rpcClient == nil {
+			return 0, merrors.Internal("rpc client not initialised")
+		}
+		return estimateGasTron(ctx, rpcClient, callMsg)
+	}
+	return client.EstimateGas(ctx, callMsg)
+}
+
+func estimateGasTron(ctx context.Context, rpcClient *rpc.Client, callMsg ethereum.CallMsg) (uint64, error) {
+	call := tronEstimateCall(callMsg)
+	var hexResp string
+	if err := rpcClient.CallContext(ctx, &hexResp, "eth_estimateGas", call); err != nil {
+		return 0, err
+	}
+	val, err := shared.DecodeHexBig(hexResp)
+	if err != nil {
+		return 0, err
+	}
+	if val == nil {
+		return 0, merrors.Internal("failed to decode gas estimate")
+	}
+	return val.Uint64(), nil
+}
+
+func tronEstimateCall(callMsg ethereum.CallMsg) map[string]string {
+	call := make(map[string]string)
+	if callMsg.From != (common.Address{}) {
+		call["from"] = strings.ToLower(callMsg.From.Hex())
+	}
+	if callMsg.To != nil {
+		call["to"] = strings.ToLower(callMsg.To.Hex())
+	}
+	if callMsg.Gas > 0 {
+		call["gas"] = hexutil.EncodeUint64(callMsg.Gas)
+	}
+	if callMsg.GasPrice != nil {
+		call["gasPrice"] = hexutil.EncodeBig(callMsg.GasPrice)
+	}
+	if callMsg.Value != nil {
+		call["value"] = hexutil.EncodeBig(callMsg.Value)
+	}
+	if len(callMsg.Data) > 0 {
+		call["data"] = hexutil.Encode(callMsg.Data)
+	}
+	return call
+}
+
+func isTronNetwork(network shared.Network) bool {
+	return strings.HasPrefix(strings.ToLower(strings.TrimSpace(network.Name)), "tron")
+}
+
 func toBaseUnits(amount string, decimals uint8) (*big.Int, error) {
 	value, err := decimal.NewFromString(strings.TrimSpace(amount))
 	if err != nil {

api/gateway/chain/internal/service/gateway/driver/tron/driver.go

@@ -2,6 +2,7 @@ package tron
 
 import (
 	"context"
+	"strings"
 
 	"github.com/ethereum/go-ethereum/core/types"
 	"github.com/tech/sendico/gateway/chain/internal/service/gateway/driver"
@@ -113,6 +114,9 @@ func (d *Driver) EstimateFee(ctx context.Context, deps driver.Deps, network shar
 	if wallet == nil {
 		return nil, merrors.InvalidArgument("wallet is required")
 	}
+	if amount == nil {
+		return nil, merrors.InvalidArgument("amount is required")
+	}
 	d.logger.Debug("Estimate fee request",
 		zap.String("wallet_ref", wallet.WalletRef),
 		zap.String("network", network.Name),
@@ -134,6 +138,12 @@ func (d *Driver) EstimateFee(ctx context.Context, deps driver.Deps, network shar
 		)
 		return nil, err
 	}
+	if rpcFrom == rpcTo {
+		return &moneyv1.Money{
+			Currency: nativeCurrency(network),
+			Amount:   "0",
+		}, nil
+	}
 	driverDeps := deps
 	driverDeps.Logger = d.logger
 	result, err := evm.EstimateFee(ctx, driverDeps, network, wallet, rpcFrom, rpcTo, amount)
@@ -141,6 +151,10 @@ func (d *Driver) EstimateFee(ctx context.Context, deps driver.Deps, network shar
 		d.logger.Warn("Estimate fee failed", zap.Error(err),
 			zap.String("wallet_ref", wallet.WalletRef),
 			zap.String("network", network.Name),
+			zap.String("from_address", wallet.DepositAddress),
+			zap.String("from_rpc", rpcFrom),
+			zap.String("to_address", destination),
+			zap.String("to_rpc", rpcTo),
 		)
 	} else if result != nil {
 		d.logger.Debug("Estimate fee result",
@@ -220,4 +234,12 @@ func (d *Driver) AwaitConfirmation(ctx context.Context, deps driver.Deps, networ
 	return receipt, err
 }
 
+func nativeCurrency(network shared.Network) string {
+	currency := strings.ToUpper(strings.TrimSpace(network.NativeToken))
+	if currency == "" {
+		currency = strings.ToUpper(strings.TrimSpace(network.Name))
+	}
+	return currency
+}
+
 var _ driver.Driver = (*Driver)(nil)

api/gateway/chain/internal/service/gateway/driver/tron/driver_test.go

@@ -0,0 +1,33 @@
+package tron
+
+import (
+	"context"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	"github.com/tech/sendico/gateway/chain/internal/service/gateway/driver"
+	"github.com/tech/sendico/gateway/chain/internal/service/gateway/shared"
+	"github.com/tech/sendico/gateway/chain/storage/model"
+	moneyv1 "github.com/tech/sendico/pkg/proto/common/money/v1"
+	"go.uber.org/zap"
+)
+
+func TestEstimateFeeSelfTransferReturnsZero(t *testing.T) {
+	logger := zap.NewNop()
+	d := New(logger)
+	wallet := &model.ManagedWallet{
+		WalletRef:      "wallet_ref",
+		DepositAddress: "TGBDXEg9rxSqGFJDcb889zqTjDwx1bmLRF",
+	}
+	network := shared.Network{
+		Name:        "tron_mainnet",
+		NativeToken: "TRX",
+	}
+	amount := &moneyv1.Money{Currency: "TRX", Amount: "1000000"}
+
+	fee, err := d.EstimateFee(context.Background(), driver.Deps{}, network, wallet, wallet.DepositAddress, amount)
+	require.NoError(t, err)
+	require.NotNil(t, fee)
+	require.Equal(t, "TRX", fee.GetCurrency())
+	require.Equal(t, "0", fee.GetAmount())
+}

api/gateway/chain/internal/service/gateway/executor.go

@@ -81,12 +81,12 @@ func (o *onChainExecutor) SubmitTransfer(ctx context.Context, transfer *model.Tr
 
 	client, err := o.clients.Client(network.Name)
 	if err != nil {
-		o.logger.Warn("failed to initialise rpc client", zap.Error(err), zap.String("network", network.Name))
+		o.logger.Warn("Failed to initialise RPC client", zap.Error(err), zap.String("network", network.Name))
 		return "", err
 	}
 	rpcClient, err := o.clients.RPCClient(network.Name)
 	if err != nil {
-		o.logger.Warn("failed to initialise rpc client",
+		o.logger.Warn("Failed to initialise RPC client",
 			zap.String("network", network.Name),
 			zap.Error(err),
 		)
@@ -101,7 +101,7 @@ func (o *onChainExecutor) SubmitTransfer(ctx context.Context, transfer *model.Tr
 
 	nonce, err := client.PendingNonceAt(ctx, sourceAddress)
 	if err != nil {
-		o.logger.Warn("failed to fetch nonce", zap.Error(err),
+		o.logger.Warn("Failed to fetch nonce", zap.Error(err),
 			zap.String("transfer_ref", transfer.TransferRef),
 			zap.String("wallet_ref", source.WalletRef),
 		)
@@ -110,7 +110,7 @@ func (o *onChainExecutor) SubmitTransfer(ctx context.Context, transfer *model.Tr
 
 	gasPrice, err := client.SuggestGasPrice(ctx)
 	if err != nil {
-		o.logger.Warn("failed to suggest gas price",
+		o.logger.Warn("Failed to suggest gas price",
 			zap.String("transfer_ref", transfer.TransferRef),
 			zap.String("network", network.Name),
 			zap.Error(err),
@@ -124,12 +124,12 @@ func (o *onChainExecutor) SubmitTransfer(ctx context.Context, transfer *model.Tr
 	chainID := new(big.Int).SetUint64(network.ChainID)
 
 	if strings.TrimSpace(transfer.ContractAddress) == "" {
-		o.logger.Warn("native token transfer requested but not supported", zap.String("transfer_ref", transfer.TransferRef))
+		o.logger.Warn("Native token transfer requested but not supported", zap.String("transfer_ref", transfer.TransferRef))
 		return "", merrors.NotImplemented("executor: native token transfers not yet supported")
 	}
 
 	if !common.IsHexAddress(transfer.ContractAddress) {
-		o.logger.Warn("invalid token contract address",
+		o.logger.Warn("Invalid token contract address",
 			zap.String("transfer_ref", transfer.TransferRef),
 			zap.String("contract", transfer.ContractAddress),
 		)
@@ -139,7 +139,7 @@ func (o *onChainExecutor) SubmitTransfer(ctx context.Context, transfer *model.Tr
 
 	decimals, err := erc20Decimals(ctx, rpcClient, tokenAddress)
 	if err != nil {
-		o.logger.Warn("failed to read token decimals", zap.Error(err),
+		o.logger.Warn("Failed to read token decimals", zap.Error(err),
 			zap.String("transfer_ref", transfer.TransferRef),
 			zap.String("contract", transfer.ContractAddress),
 		)
@@ -148,12 +148,12 @@ func (o *onChainExecutor) SubmitTransfer(ctx context.Context, transfer *model.Tr
 
 	amount := transfer.NetAmount
 	if amount == nil || strings.TrimSpace(amount.Amount) == "" {
-		o.logger.Warn("transfer missing net amount", zap.String("transfer_ref", transfer.TransferRef))
+		o.logger.Warn("Transfer missing net amount", zap.String("transfer_ref", transfer.TransferRef))
 		return "", executorInvalid("transfer missing net amount")
 	}
 	amountInt, err := toBaseUnits(amount.Amount, decimals)
 	if err != nil {
-		o.logger.Warn("failed to convert amount to base units", zap.Error(err),
+		o.logger.Warn("Failed to convert amount to base units", zap.Error(err),
 			zap.String("transfer_ref", transfer.TransferRef),
 			zap.String("amount", amount.Amount),
 		)
@@ -177,7 +177,7 @@ func (o *onChainExecutor) SubmitTransfer(ctx context.Context, transfer *model.Tr
 	}
 	gasLimit, err := client.EstimateGas(ctx, callMsg)
 	if err != nil {
-		o.logger.Warn("failed to estimate gas",
+		o.logger.Warn("Failed to estimate gas",
 			zap.String("transfer_ref", transfer.TransferRef),
 			zap.Error(err),
 		)
@@ -188,7 +188,7 @@ func (o *onChainExecutor) SubmitTransfer(ctx context.Context, transfer *model.Tr
 
 	signedTx, err := o.keyManager.SignTransaction(ctx, source.KeyReference, tx, chainID)
 	if err != nil {
-		o.logger.Warn("failed to sign transaction", zap.Error(err),
+		o.logger.Warn("Failed to sign transaction", zap.Error(err),
 			zap.String("transfer_ref", transfer.TransferRef),
 			zap.String("wallet_ref", source.WalletRef),
 		)
@@ -196,14 +196,14 @@ func (o *onChainExecutor) SubmitTransfer(ctx context.Context, transfer *model.Tr
 	}
 
 	if err := client.SendTransaction(ctx, signedTx); err != nil {
-		o.logger.Warn("failed to send transaction", zap.Error(err),
+		o.logger.Warn("Failed to send transaction", zap.Error(err),
 			zap.String("transfer_ref", transfer.TransferRef),
 		)
 		return "", executorInternal("failed to send transaction", err)
 	}
 
 	txHash = signedTx.Hash().Hex()
-	o.logger.Info("transaction submitted",
+	o.logger.Info("Transaction submitted",
 		zap.String("transfer_ref", transfer.TransferRef),
 		zap.String("tx_hash", txHash),
 		zap.String("network", network.Name),
@@ -214,12 +214,12 @@ func (o *onChainExecutor) SubmitTransfer(ctx context.Context, transfer *model.Tr
 
 func (o *onChainExecutor) AwaitConfirmation(ctx context.Context, network shared.Network, txHash string) (*types.Receipt, error) {
 	if strings.TrimSpace(txHash) == "" {
-		o.logger.Warn("missing transaction hash for confirmation", zap.String("network", network.Name))
+		o.logger.Warn("Missing transaction hash for confirmation", zap.String("network", network.Name))
 		return nil, executorInvalid("tx hash is required")
 	}
 	rpcURL := strings.TrimSpace(network.RPCURL)
 	if rpcURL == "" {
-		o.logger.Warn("network rpc url missing while awaiting confirmation", zap.String("tx_hash", txHash))
+		o.logger.Warn("Network RPC url missing while awaiting confirmation", zap.String("tx_hash", txHash))
 		return nil, executorInvalid("network rpc url is not configured")
 	}
 
@@ -238,27 +238,27 @@ func (o *onChainExecutor) AwaitConfirmation(ctx context.Context, network shared.
 			if errors.Is(err, ethereum.NotFound) {
 				select {
 				case <-ticker.C:
-					o.logger.Debug("transaction not yet mined",
+					o.logger.Debug("Transaction not yet mined",
 						zap.String("tx_hash", txHash),
 						zap.String("network", network.Name),
 					)
 					continue
 				case <-ctx.Done():
-					o.logger.Warn("context cancelled while awaiting confirmation",
+					o.logger.Warn("Context cancelled while awaiting confirmation",
 						zap.String("tx_hash", txHash),
 						zap.String("network", network.Name),
 					)
 					return nil, ctx.Err()
 				}
 			}
-			o.logger.Warn("failed to fetch transaction receipt",
+			o.logger.Warn("Failed to fetch transaction receipt",
 				zap.String("tx_hash", txHash),
 				zap.String("network", network.Name),
 				zap.Error(err),
 			)
 			return nil, executorInternal("failed to fetch transaction receipt", err)
 		}
-		o.logger.Info("transaction confirmed",
+		o.logger.Info("Transaction confirmed",
 			zap.String("tx_hash", txHash),
 			zap.String("network", network.Name),
 			zap.Uint64("block_number", receipt.BlockNumber.Uint64()),

api/gateway/chain/internal/service/gateway/rpcclient/clients.go

@@ -2,6 +2,7 @@ package rpcclient
 
 import (
 	"context"
+	"encoding/json"
 	"fmt"
 	"io"
 	"net/http"
@@ -70,7 +71,7 @@ func Prepare(ctx context.Context, logger mlogger.Logger, networks []shared.Netwo
 		cancel()
 		if err != nil {
 			result.Close()
-			clientLogger.Warn("failed to dial rpc endpoint", append(fields, zap.Error(err))...)
+			clientLogger.Warn("Failed to dial rpc endpoint", append(fields, zap.Error(err))...)
 			return nil, merrors.Internal(fmt.Sprintf("rpc dial failed for %s: %s", name, err.Error()))
 		}
 		client := ethclient.NewClient(rpcCli)
@@ -78,7 +79,7 @@ func Prepare(ctx context.Context, logger mlogger.Logger, networks []shared.Netwo
 			eth: client,
 			rpc: rpcCli,
 		}
-		clientLogger.Info("rpc client ready", fields...)
+		clientLogger.Info("RPC client ready", fields...)
 	}
 
 	if len(result.clients) == 0 {
@@ -94,12 +95,12 @@ func Prepare(ctx context.Context, logger mlogger.Logger, networks []shared.Netwo
 // Client returns a prepared client for the given network name.
 func (c *Clients) Client(network string) (*ethclient.Client, error) {
 	if c == nil {
-		return nil, merrors.Internal("rpc clients not initialised")
+		return nil, merrors.Internal("RPC clients not initialised")
 	}
 	name := strings.ToLower(strings.TrimSpace(network))
 	entry, ok := c.clients[name]
 	if !ok || entry.eth == nil {
-		return nil, merrors.InvalidArgument(fmt.Sprintf("rpc client not configured for network %s", name))
+		return nil, merrors.InvalidArgument(fmt.Sprintf("RPC client not configured for network %s", name))
 	}
 	return entry.eth, nil
 }
@@ -129,7 +130,7 @@ func (c *Clients) Close() {
 			entry.eth.Close()
 		}
 		if c.logger != nil {
-			c.logger.Info("rpc client closed", zap.String("network", name))
+			c.logger.Info("RPC client closed", zap.String("network", name))
 		}
 	}
 }
@@ -155,16 +156,15 @@ func (l *loggingRoundTripper) RoundTrip(req *http.Request) (*http.Response, erro
 
 	fields := []zap.Field{
 		zap.String("network", l.network),
-		zap.String("rpc_endpoint", l.endpoint),
 	}
 	if len(reqBody) > 0 {
 		fields = append(fields, zap.String("rpc_request", truncate(string(reqBody), 2048)))
 	}
-	l.logger.Debug("rpc request", fields...)
+	l.logger.Debug("RPC request", fields...)
 
 	resp, err := l.base.RoundTrip(req)
 	if err != nil {
-		l.logger.Warn("rpc http request failed", append(fields, zap.Error(err))...)
+		l.logger.Warn("RPC http request failed", append(fields, zap.Error(err))...)
 		return nil, err
 	}
 
@@ -175,11 +175,19 @@ func (l *loggingRoundTripper) RoundTrip(req *http.Request) (*http.Response, erro
 	respFields := append(fields,
 		zap.Int("status_code", resp.StatusCode),
 	)
+	if contentType := strings.TrimSpace(resp.Header.Get("Content-Type")); contentType != "" {
+		respFields = append(respFields, zap.String("content_type", contentType))
+	}
 	if len(bodyBytes) > 0 {
 		respFields = append(respFields, zap.String("rpc_response", truncate(string(bodyBytes), 2048)))
 	}
+	l.logger.Debug("RPC response", respFields...)
 	if resp.StatusCode >= 400 {
 		l.logger.Warn("RPC response error", respFields...)
+	} else if len(bodyBytes) == 0 {
+		l.logger.Warn("RPC response empty body", respFields...)
+	} else if len(bodyBytes) > 0 && !json.Valid(bodyBytes) {
+		l.logger.Warn("RPC response invalid JSON", respFields...)
 	}
 
 	return resp, nil

api/gateway/chain/internal/service/gateway/shared/helpers.go

@@ -119,6 +119,15 @@ func TransferStatusToProto(status model.TransferStatus) chainv1.TransferStatus {
 	}
 }
 
+// NativeCurrency returns the canonical native token symbol for a network.
+func NativeCurrency(network Network) string {
+	currency := strings.ToUpper(strings.TrimSpace(network.NativeToken))
+	if currency == "" {
+		currency = strings.ToUpper(strings.TrimSpace(network.Name))
+	}
+	return currency
+}
+
 // Network describes a supported blockchain network and known token contracts.
 type Network struct {
 	Name           string

api/gateway/chain/internal/service/gateway/transfer_execution.go

@@ -24,7 +24,7 @@ func (s *Service) launchTransferExecution(transferRef, sourceWalletRef string, n
 		defer cancel()
 
 		if err := s.executeTransfer(ctx, ref, walletRef, net); err != nil {
-			s.logger.Warn("failed to execute transfer", zap.String("transfer_ref", ref), zap.Error(err))
+			s.logger.Warn("Failed to execute transfer", zap.String("transfer_ref", ref), zap.Error(err))
 		}
 	}(transferRef, sourceWalletRef, network)
 }
@@ -57,6 +57,23 @@ func (s *Service) executeTransfer(ctx context.Context, transferRef, sourceWallet
 		return err
 	}
 
+	sourceAddress, err := chainDriver.NormalizeAddress(sourceWallet.DepositAddress)
+	if err != nil {
+		_, _ = s.storage.Transfers().UpdateStatus(ctx, transferRef, model.TransferStatusFailed, err.Error(), "")
+		return err
+	}
+	if chainDriver.Name() == "tron" && sourceAddress == destinationAddress {
+		s.logger.Info("Self transfer detected; skipping submission",
+			zap.String("transfer_ref", transferRef),
+			zap.String("wallet_ref", sourceWalletRef),
+			zap.String("network", network.Name),
+		)
+		if _, err := s.storage.Transfers().UpdateStatus(ctx, transferRef, model.TransferStatusConfirmed, "", ""); err != nil {
+			s.logger.Warn("Failed to update transfer status to confirmed", zap.String("transfer_ref", transferRef), zap.Error(err))
+		}
+		return nil
+	}
+
 	txHash, err := chainDriver.SubmitTransfer(ctx, driverDeps, network, transfer, sourceWallet, destinationAddress)
 	if err != nil {
 		_, _ = s.storage.Transfers().UpdateStatus(ctx, transferRef, model.TransferStatusFailed, err.Error(), "")

api/gateway/chain/storage/mongo/store/wallets.go

@@ -99,24 +99,49 @@ func (w *Wallets) Create(ctx context.Context, wallet *model.ManagedWallet) (*mod
 	if strings.TrimSpace(wallet.IdempotencyKey) == "" {
 		return nil, merrors.InvalidArgument("walletsStore: empty idempotencyKey")
 	}
+	fields := []zap.Field{
+		zap.String("wallet_ref", wallet.WalletRef),
+		zap.String("idempotency_key", wallet.IdempotencyKey),
+	}
+	if wallet.OrganizationRef != "" {
+		fields = append(fields, zap.String("organization_ref", wallet.OrganizationRef))
+	}
+	if wallet.OwnerRef != "" {
+		fields = append(fields, zap.String("owner_ref", wallet.OwnerRef))
+	}
+	if wallet.Network != "" {
+		fields = append(fields, zap.String("network", wallet.Network))
+	}
+	if wallet.TokenSymbol != "" {
+		fields = append(fields, zap.String("token_symbol", wallet.TokenSymbol))
+	}
 	if err := w.walletRepo.Insert(ctx, wallet, repository.Filter("idempotencyKey", wallet.IdempotencyKey)); err != nil {
 		if errors.Is(err, merrors.ErrDataConflict) {
-			w.logger.Debug("wallet already exists", zap.String("wallet_ref", wallet.WalletRef), zap.String("idempotency_key", wallet.IdempotencyKey))
+			w.logger.Debug("wallet already exists", fields...)
 			return wallet, nil
 		}
+		w.logger.Warn("wallet create failed", append(fields, zap.Error(err))...)
 		return nil, err
 	}
-	w.logger.Debug("wallet created", zap.String("wallet_ref", wallet.WalletRef))
+	w.logger.Debug("wallet created", fields...)
 	return wallet, nil
 }
 
-func (w *Wallets) Get(ctx context.Context, walletRef string) (*model.ManagedWallet, error) {
-	walletRef = strings.TrimSpace(walletRef)
-	if walletRef == "" {
+func (w *Wallets) Get(ctx context.Context, walletID string) (*model.ManagedWallet, error) {
+	walletID = strings.TrimSpace(walletID)
+	if walletID == "" {
 		return nil, merrors.InvalidArgument("walletsStore: empty walletRef")
 	}
+	fields := []zap.Field{
+		zap.String("wallet_id", walletID),
+	}
 	wallet := &model.ManagedWallet{}
-	if err := w.walletRepo.FindOneByFilter(ctx, repository.Filter("walletRef", walletRef), wallet); err != nil {
+	if err := w.balanceRepo.FindOneByFilter(ctx, repository.Filter("walletRef", walletID), wallet); err != nil {
+		if errors.Is(err, merrors.ErrNoData) {
+			w.logger.Debug("wallet not found", fields...)
+		} else {
+			w.logger.Warn("wallet lookup failed", append(fields, zap.Error(err))...)
+		}
 		return nil, err
 	}
 	return wallet, nil
@@ -124,29 +149,38 @@ func (w *Wallets) Get(ctx context.Context, walletRef string) (*model.ManagedWall
 
 func (w *Wallets) List(ctx context.Context, filter model.ManagedWalletFilter) (*model.ManagedWalletList, error) {
 	query := repository.Query()
+	fields := make([]zap.Field, 0, 6)
 
 	if org := strings.TrimSpace(filter.OrganizationRef); org != "" {
 		query = query.Filter(repository.Field("organizationRef"), org)
+		fields = append(fields, zap.String("organization_ref", org))
 	}
 	if owner := strings.TrimSpace(filter.OwnerRef); owner != "" {
 		query = query.Filter(repository.Field("ownerRef"), owner)
+		fields = append(fields, zap.String("owner_ref", owner))
 	}
 	if network := strings.TrimSpace(filter.Network); network != "" {
-		query = query.Filter(repository.Field("network"), strings.ToLower(network))
+		normalized := strings.ToLower(network)
+		query = query.Filter(repository.Field("network"), normalized)
+		fields = append(fields, zap.String("network", normalized))
 	}
 	if token := strings.TrimSpace(filter.TokenSymbol); token != "" {
-		query = query.Filter(repository.Field("tokenSymbol"), strings.ToUpper(token))
+		normalized := strings.ToUpper(token)
+		query = query.Filter(repository.Field("tokenSymbol"), normalized)
+		fields = append(fields, zap.String("token_symbol", normalized))
 	}
 
 	if cursor := strings.TrimSpace(filter.Cursor); cursor != "" {
 		if oid, err := primitive.ObjectIDFromHex(cursor); err == nil {
 			query = query.Comparison(repository.IDField(), builder.Gt, oid)
+			fields = append(fields, zap.String("cursor", cursor))
 		} else {
 			w.logger.Warn("ignoring invalid wallet cursor", zap.String("cursor", cursor), zap.Error(err))
 		}
 	}
 
 	limit := sanitizeWalletLimit(filter.Limit)
+	fields = append(fields, zap.Int64("limit", limit))
 	fetchLimit := limit + 1
 	query = query.Sort(repository.IDField(), true).Limit(&fetchLimit)
 
@@ -160,8 +194,10 @@ func (w *Wallets) List(ctx context.Context, filter model.ManagedWalletFilter) (*
 		return nil
 	}
 
-	if err := w.walletRepo.FindManyByFilter(ctx, query, decoder); err != nil && !errors.Is(err, merrors.ErrNoData) {
-		return nil, err
+	listErr := w.walletRepo.FindManyByFilter(ctx, query, decoder)
+	if listErr != nil && !errors.Is(listErr, merrors.ErrNoData) {
+		w.logger.Warn("wallet list failed", append(fields, zap.Error(listErr))...)
+		return nil, listErr
 	}
 
 	nextCursor := ""
@@ -171,10 +207,21 @@ func (w *Wallets) List(ctx context.Context, filter model.ManagedWalletFilter) (*
 		wallets = wallets[:len(wallets)-1]
 	}
 
-	return &model.ManagedWalletList{
+	result := &model.ManagedWalletList{
 		Items:      wallets,
 		NextCursor: nextCursor,
-	}, nil
+	}
+
+	fields = append(fields,
+		zap.Int("count", len(result.Items)),
+		zap.String("next_cursor", result.NextCursor),
+	)
+	if errors.Is(listErr, merrors.ErrNoData) {
+		w.logger.Debug("wallet list empty", fields...)
+	} else {
+		w.logger.Debug("wallet list fetched", fields...)
+	}
+	return result, nil
 }
 
 func (w *Wallets) SaveBalance(ctx context.Context, balance *model.WalletBalance) error {
@@ -188,6 +235,7 @@ func (w *Wallets) SaveBalance(ctx context.Context, balance *model.WalletBalance)
 	if balance.CalculatedAt.IsZero() {
 		balance.CalculatedAt = time.Now().UTC()
 	}
+	fields := []zap.Field{zap.String("wallet_ref", balance.WalletRef)}
 
 	existing := &model.WalletBalance{}
 	err := w.balanceRepo.FindOneByFilter(ctx, repository.Filter("walletRef", balance.WalletRef), existing)
@@ -198,28 +246,40 @@ func (w *Wallets) SaveBalance(ctx context.Context, balance *model.WalletBalance)
 		existing.PendingOutbound = balance.PendingOutbound
 		existing.CalculatedAt = balance.CalculatedAt
 		if err := w.balanceRepo.Update(ctx, existing); err != nil {
+			w.logger.Warn("wallet balance update failed", append(fields, zap.Error(err))...)
 			return err
 		}
+		w.logger.Debug("wallet balance updated", fields...)
 		return nil
 	case errors.Is(err, merrors.ErrNoData):
 		if err := w.balanceRepo.Insert(ctx, balance, repository.Filter("walletRef", balance.WalletRef)); err != nil {
+			w.logger.Warn("wallet balance create failed", append(fields, zap.Error(err))...)
 			return err
 		}
+		w.logger.Debug("wallet balance created", fields...)
 		return nil
 	default:
+		w.logger.Warn("wallet balance lookup failed", append(fields, zap.Error(err))...)
 		return err
 	}
 }
 
-func (w *Wallets) GetBalance(ctx context.Context, walletRef string) (*model.WalletBalance, error) {
-	walletRef = strings.TrimSpace(walletRef)
-	if walletRef == "" {
+func (w *Wallets) GetBalance(ctx context.Context, walletID string) (*model.WalletBalance, error) {
+	walletID = strings.TrimSpace(walletID)
+	if walletID == "" {
 		return nil, merrors.InvalidArgument("walletsStore: empty walletRef")
 	}
+	fields := []zap.Field{zap.String("wallet_ref", walletID)}
 	balance := &model.WalletBalance{}
-	if err := w.balanceRepo.FindOneByFilter(ctx, repository.Filter("walletRef", walletRef), balance); err != nil {
+	if err := w.balanceRepo.FindOneByFilter(ctx, repository.Filter("walletRef", walletID), balance); err != nil {
+		if errors.Is(err, merrors.ErrNoData) {
+			w.logger.Debug("wallet balance not found", fields...)
+		} else {
+			w.logger.Warn("wallet balance lookup failed", append(fields, zap.Error(err))...)
+		}
 		return nil, err
 	}
+	w.logger.Debug("wallet balance fetched", fields...)
 	return balance, nil
 }
 

api/gateway/mntx/config.yml

@@ -26,7 +26,7 @@ monetix:
   base_url_env: MONETIX_BASE_URL
   project_id_env: MONETIX_PROJECT_ID
   secret_key_env: MONETIX_SECRET_KEY
-  allowed_currencies: ["USD", "EUR"]
+  allowed_currencies: ["RUB"]
   require_customer_address: false
   request_timeout_seconds: 15
   status_success: "success"

api/gateway/mntx/internal/server/internal/serverimp.go

@@ -95,22 +95,49 @@ func (i *Imp) Shutdown() {
 }
 
 func (i *Imp) Start() error {
+	i.logger.Info("Starting Monetix gateway", zap.String("config_file", i.file), zap.Bool("debug", i.debug))
+
 	cfg, err := i.loadConfig()
 	if err != nil {
 		return err
 	}
 	i.config = cfg
 
+	i.logger.Info("Configuration loaded",
+		zap.String("grpc_address", cfg.GRPC.Address),
+		zap.String("metrics_address", cfg.Metrics.Address),
+	)
+
 	monetixCfg, err := i.resolveMonetixConfig(cfg.Monetix)
 	if err != nil {
+		i.logger.Error("Failed to resolve Monetix configuration", zap.Error(err))
 		return err
 	}
 
 	callbackCfg, err := i.resolveCallbackConfig(cfg.HTTP.Callback)
 	if err != nil {
+		i.logger.Error("Failed to resolve callback configuration", zap.Error(err))
 		return err
 	}
 
+	i.logger.Info("Monetix configuration resolved",
+		zap.Bool("base_url_set", strings.TrimSpace(monetixCfg.BaseURL) != ""),
+		zap.Int64("project_id", monetixCfg.ProjectID),
+		zap.Bool("secret_key_set", strings.TrimSpace(monetixCfg.SecretKey) != ""),
+		zap.Int("allowed_currencies", len(monetixCfg.AllowedCurrencies)),
+		zap.Bool("require_customer_address", monetixCfg.RequireCustomerAddress),
+		zap.Duration("request_timeout", monetixCfg.RequestTimeout),
+		zap.String("status_success", monetixCfg.SuccessStatus()),
+		zap.String("status_processing", monetixCfg.ProcessingStatus()),
+	)
+
+	i.logger.Info("Callback configuration resolved",
+		zap.String("address", callbackCfg.Address),
+		zap.String("path", callbackCfg.Path),
+		zap.Int("allowed_cidrs", len(callbackCfg.AllowedCIDRs)),
+		zap.Int64("max_body_bytes", callbackCfg.MaxBodyBytes),
+	)
+
 	serviceFactory := func(logger mlogger.Logger, _ struct{}, producer msg.Producer) (grpcapp.Service, error) {
 		svc := mntxservice.NewService(logger,
 			mntxservice.WithProducer(producer),
@@ -137,7 +164,7 @@ func (i *Imp) Start() error {
 func (i *Imp) loadConfig() (*config, error) {
 	data, err := os.ReadFile(i.file)
 	if err != nil {
-		i.logger.Error("could not read configuration file", zap.String("config_file", i.file), zap.Error(err))
+		i.logger.Error("Could not read configuration file", zap.String("config_file", i.file), zap.Error(err))
 		return nil, err
 	}
 
@@ -145,7 +172,7 @@ func (i *Imp) loadConfig() (*config, error) {
 		Config: &grpcapp.Config{},
 	}
 	if err := yaml.Unmarshal(data, cfg); err != nil {
-		i.logger.Error("failed to parse configuration", zap.Error(err))
+		i.logger.Error("Failed to parse configuration", zap.Error(err))
 		return nil, err
 	}
 
@@ -245,7 +272,7 @@ func (i *Imp) resolveCallbackConfig(cfg callbackConfig) (callbackRuntimeConfig,
 		}
 		_, block, err := net.ParseCIDR(clean)
 		if err != nil {
-			i.logger.Warn("invalid callback allowlist CIDR skipped", zap.String("cidr", clean), zap.Error(err))
+			i.logger.Warn("Invalid callback allowlist CIDR skipped", zap.String("cidr", clean), zap.Error(err))
 			continue
 		}
 		cidrs = append(cidrs, block)
@@ -270,20 +297,36 @@ func (i *Imp) startHTTPCallbackServer(svc *mntxservice.Service, cfg callbackRunt
 
 	router := chi.NewRouter()
 	router.Post(cfg.Path, func(w http.ResponseWriter, r *http.Request) {
+		log := i.logger.Named("callback_http")
+		log.Debug("Callback request received",
+			zap.String("remote_addr", strings.TrimSpace(r.RemoteAddr)),
+			zap.String("path", r.URL.Path),
+			zap.String("method", r.Method),
+		)
+
 		if len(cfg.AllowedCIDRs) > 0 && !clientAllowed(r, cfg.AllowedCIDRs) {
+			ip := clientIPFromRequest(r)
+			remoteIP := ""
+			if ip != nil {
+				remoteIP = ip.String()
+			}
+			log.Warn("Callback rejected by CIDR allowlist", zap.String("remote_ip", remoteIP))
 			http.Error(w, "forbidden", http.StatusForbidden)
 			return
 		}
 		body, err := io.ReadAll(io.LimitReader(r.Body, cfg.MaxBodyBytes))
 		if err != nil {
+			log.Warn("Callback body read failed", zap.Error(err))
 			http.Error(w, "failed to read body", http.StatusBadRequest)
 			return
 		}
 		status, err := svc.ProcessMonetixCallback(r.Context(), body)
 		if err != nil {
+			log.Warn("Callback processing failed", zap.Error(err), zap.Int("status", status))
 			http.Error(w, err.Error(), status)
 			return
 		}
+		log.Debug("Callback processed", zap.Int("status", status))
 		w.WriteHeader(status)
 	})
 
@@ -301,7 +344,7 @@ func (i *Imp) startHTTPCallbackServer(svc *mntxservice.Service, cfg callbackRunt
 
 	go func() {
 		if err := server.Serve(ln); err != nil && !errors.Is(err, http.ErrServerClosed) {
-			i.logger.Error("Monetix callback server stopped with error", zap.Error(err))
+			i.logger.Warn("Monetix callback server stopped with error", zap.Error(err))
 		}
 	}()
 

api/gateway/mntx/internal/server/internal/serverimp_test.go

@@ -0,0 +1,52 @@
+package serverimp
+
+import (
+	"net"
+	"net/http"
+	"testing"
+)
+
+func TestClientIPFromRequest(t *testing.T) {
+	req := &http.Request{
+		Header:     http.Header{"X-Forwarded-For": []string{"1.2.3.4, 5.6.7.8"}},
+		RemoteAddr: "9.8.7.6:1234",
+	}
+	ip := clientIPFromRequest(req)
+	if ip == nil || ip.String() != "1.2.3.4" {
+		t.Fatalf("expected forwarded ip, got %v", ip)
+	}
+
+	req = &http.Request{RemoteAddr: "9.8.7.6:1234"}
+	ip = clientIPFromRequest(req)
+	if ip == nil || ip.String() != "9.8.7.6" {
+		t.Fatalf("expected remote addr ip, got %v", ip)
+	}
+
+	req = &http.Request{RemoteAddr: "invalid"}
+	ip = clientIPFromRequest(req)
+	if ip != nil {
+		t.Fatalf("expected nil ip, got %v", ip)
+	}
+}
+
+func TestClientAllowed(t *testing.T) {
+	_, cidr, err := net.ParseCIDR("10.0.0.0/8")
+	if err != nil {
+		t.Fatalf("failed to parse cidr: %v", err)
+	}
+
+	allowedReq := &http.Request{RemoteAddr: "10.1.2.3:1234"}
+	if !clientAllowed(allowedReq, []*net.IPNet{cidr}) {
+		t.Fatalf("expected allowed request")
+	}
+
+	deniedReq := &http.Request{RemoteAddr: "8.8.8.8:1234"}
+	if clientAllowed(deniedReq, []*net.IPNet{cidr}) {
+		t.Fatalf("expected denied request")
+	}
+
+	openReq := &http.Request{RemoteAddr: "8.8.8.8:1234"}
+	if !clientAllowed(openReq, nil) {
+		t.Fatalf("expected allow when no cidrs are configured")
+	}
+}

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

@@ -10,6 +10,7 @@ import (
 	clockpkg "github.com/tech/sendico/pkg/clock"
 	"github.com/tech/sendico/pkg/merrors"
 	mntxv1 "github.com/tech/sendico/pkg/proto/gateway/mntx/v1"
+	"go.uber.org/zap"
 	"google.golang.org/protobuf/types/known/timestamppb"
 )
 
@@ -66,9 +67,12 @@ type monetixCallback struct {
 
 // ProcessMonetixCallback ingests Monetix provider callbacks and updates payout state.
 func (s *Service) ProcessMonetixCallback(ctx context.Context, payload []byte) (int, error) {
+	log := s.logger.Named("callback")
 	if s.card == nil {
+		log.Warn("Card payout processor not initialised")
 		return http.StatusInternalServerError, merrors.Internal("card payout processor not initialised")
 	}
+	log.Debug("Callback processing requested", zap.Int("payload_bytes", len(payload)))
 	return s.card.ProcessCallback(ctx, payload)
 }
 

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

@@ -0,0 +1,130 @@
+package gateway
+
+import (
+	"testing"
+	"time"
+
+	"github.com/tech/sendico/gateway/mntx/internal/service/monetix"
+	mntxv1 "github.com/tech/sendico/pkg/proto/gateway/mntx/v1"
+)
+
+type fixedClock struct {
+	now time.Time
+}
+
+func (f fixedClock) Now() time.Time {
+	return f.now
+}
+
+func baseCallback() monetixCallback {
+	cb := monetixCallback{
+		ProjectID: 42,
+	}
+	cb.Payment.ID = "payout-1"
+	cb.Payment.Status = "success"
+	cb.Payment.Sum.Amount = 5000
+	cb.Payment.Sum.Currency = "usd"
+	cb.Customer.ID = "cust-1"
+	cb.Operation.Status = "success"
+	cb.Operation.Code = ""
+	cb.Operation.Message = "ok"
+	cb.Operation.RequestID = "req-1"
+	cb.Operation.Provider.PaymentID = "prov-1"
+	return cb
+}
+
+func TestMapCallbackToState_StatusMapping(t *testing.T) {
+	now := time.Date(2024, 1, 2, 3, 4, 5, 0, time.UTC)
+	cfg := monetix.DefaultConfig()
+
+	cases := []struct {
+		name           string
+		paymentStatus  string
+		operationStatus string
+		code           string
+		expectedStatus mntxv1.PayoutStatus
+		expectedOutcome string
+	}{
+		{
+			name:            "success",
+			paymentStatus:   "success",
+			operationStatus: "success",
+			code:            "0",
+			expectedStatus:  mntxv1.PayoutStatus_PAYOUT_STATUS_PROCESSED,
+			expectedOutcome: monetix.OutcomeSuccess,
+		},
+		{
+			name:            "processing",
+			paymentStatus:   "processing",
+			operationStatus: "success",
+			code:            "",
+			expectedStatus:  mntxv1.PayoutStatus_PAYOUT_STATUS_PENDING,
+			expectedOutcome: monetix.OutcomeProcessing,
+		},
+		{
+			name:            "decline",
+			paymentStatus:   "failed",
+			operationStatus: "failed",
+			code:            "1",
+			expectedStatus:  mntxv1.PayoutStatus_PAYOUT_STATUS_FAILED,
+			expectedOutcome: monetix.OutcomeDecline,
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			cb := baseCallback()
+			cb.Payment.Status = tc.paymentStatus
+			cb.Operation.Status = tc.operationStatus
+			cb.Operation.Code = tc.code
+
+			state, outcome := mapCallbackToState(fixedClock{now: now}, cfg, cb)
+			if state.Status != tc.expectedStatus {
+				t.Fatalf("expected status %v, got %v", tc.expectedStatus, state.Status)
+			}
+			if outcome != tc.expectedOutcome {
+				t.Fatalf("expected outcome %q, got %q", tc.expectedOutcome, outcome)
+			}
+			if state.Currency != "USD" {
+				t.Fatalf("expected currency USD, got %q", state.Currency)
+			}
+			if !state.UpdatedAt.AsTime().Equal(now) {
+				t.Fatalf("expected updated_at %v, got %v", now, state.UpdatedAt.AsTime())
+			}
+		})
+	}
+}
+
+func TestFallbackProviderPaymentID(t *testing.T) {
+	cb := baseCallback()
+	if got := fallbackProviderPaymentID(cb); got != "prov-1" {
+		t.Fatalf("expected provider payment id, got %q", got)
+	}
+	cb.Operation.Provider.PaymentID = ""
+	if got := fallbackProviderPaymentID(cb); got != "req-1" {
+		t.Fatalf("expected request id fallback, got %q", got)
+	}
+	cb.Operation.RequestID = ""
+	if got := fallbackProviderPaymentID(cb); got != "payout-1" {
+		t.Fatalf("expected payment id fallback, got %q", got)
+	}
+}
+
+func TestVerifyCallbackSignature(t *testing.T) {
+	secret := "secret"
+	cb := baseCallback()
+
+	sig, err := monetix.SignPayload(cb, secret)
+	if err != nil {
+		t.Fatalf("failed to sign payload: %v", err)
+	}
+	cb.Signature = sig
+	if err := verifyCallbackSignature(cb, secret); err != nil {
+		t.Fatalf("expected valid signature, got %v", err)
+	}
+
+	cb.Signature = "invalid"
+	if err := verifyCallbackSignature(cb, secret); err == nil {
+		t.Fatalf("expected signature mismatch error")
+	}
+}

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

@@ -9,6 +9,7 @@ import (
 	"github.com/tech/sendico/pkg/merrors"
 	"github.com/tech/sendico/pkg/mservice"
 	mntxv1 "github.com/tech/sendico/pkg/proto/gateway/mntx/v1"
+	"go.uber.org/zap"
 	"google.golang.org/protobuf/proto"
 )
 
@@ -17,14 +18,24 @@ func (s *Service) CreateCardPayout(ctx context.Context, req *mntxv1.CardPayoutRe
 }
 
 func (s *Service) handleCreateCardPayout(ctx context.Context, req *mntxv1.CardPayoutRequest) gsresponse.Responder[mntxv1.CardPayoutResponse] {
+	log := s.logger.Named("card_payout")
+	log.Info("Create card payout request received",
+		zap.String("payout_id", strings.TrimSpace(req.GetPayoutId())),
+		zap.String("customer_id", strings.TrimSpace(req.GetCustomerId())),
+		zap.Int64("amount_minor", req.GetAmountMinor()),
+		zap.String("currency", strings.ToUpper(strings.TrimSpace(req.GetCurrency()))),
+	)
 	if s.card == nil {
+		log.Warn("Card payout processor not initialised")
 		return gsresponse.Internal[mntxv1.CardPayoutResponse](s.logger, mservice.MntxGateway, merrors.Internal("card payout processor not initialised"))
 	}
 
 	resp, err := s.card.Submit(ctx, req)
 	if err != nil {
+		log.Warn("Card payout submission failed", zap.Error(err))
 		return gsresponse.Auto[mntxv1.CardPayoutResponse](s.logger, mservice.MntxGateway, err)
 	}
+	log.Info("Card payout submission completed", zap.String("payout_id", resp.GetPayout().GetPayoutId()), zap.Bool("accepted", resp.GetAccepted()))
 	return gsresponse.Success(resp)
 }
 
@@ -33,14 +44,24 @@ func (s *Service) CreateCardTokenPayout(ctx context.Context, req *mntxv1.CardTok
 }
 
 func (s *Service) handleCreateCardTokenPayout(ctx context.Context, req *mntxv1.CardTokenPayoutRequest) gsresponse.Responder[mntxv1.CardTokenPayoutResponse] {
+	log := s.logger.Named("card_token_payout")
+	log.Info("Create card token payout request received",
+		zap.String("payout_id", strings.TrimSpace(req.GetPayoutId())),
+		zap.String("customer_id", strings.TrimSpace(req.GetCustomerId())),
+		zap.Int64("amount_minor", req.GetAmountMinor()),
+		zap.String("currency", strings.ToUpper(strings.TrimSpace(req.GetCurrency()))),
+	)
 	if s.card == nil {
+		log.Warn("Card payout processor not initialised")
 		return gsresponse.Internal[mntxv1.CardTokenPayoutResponse](s.logger, mservice.MntxGateway, merrors.Internal("card payout processor not initialised"))
 	}
 
 	resp, err := s.card.SubmitToken(ctx, req)
 	if err != nil {
+		log.Warn("Card token payout submission failed", zap.Error(err))
 		return gsresponse.Auto[mntxv1.CardTokenPayoutResponse](s.logger, mservice.MntxGateway, err)
 	}
+	log.Info("Card token payout submission completed", zap.String("payout_id", resp.GetPayout().GetPayoutId()), zap.Bool("accepted", resp.GetAccepted()))
 	return gsresponse.Success(resp)
 }
 
@@ -49,14 +70,22 @@ func (s *Service) CreateCardToken(ctx context.Context, req *mntxv1.CardTokenizeR
 }
 
 func (s *Service) handleCreateCardToken(ctx context.Context, req *mntxv1.CardTokenizeRequest) gsresponse.Responder[mntxv1.CardTokenizeResponse] {
+	log := s.logger.Named("card_tokenize")
+	log.Info("Create card token request received",
+		zap.String("request_id", strings.TrimSpace(req.GetRequestId())),
+		zap.String("customer_id", strings.TrimSpace(req.GetCustomerId())),
+	)
 	if s.card == nil {
+		log.Warn("Card payout processor not initialised")
 		return gsresponse.Internal[mntxv1.CardTokenizeResponse](s.logger, mservice.MntxGateway, merrors.Internal("card payout processor not initialised"))
 	}
 
 	resp, err := s.card.Tokenize(ctx, req)
 	if err != nil {
+		log.Warn("Card tokenization failed", zap.Error(err))
 		return gsresponse.Auto[mntxv1.CardTokenizeResponse](s.logger, mservice.MntxGateway, err)
 	}
+	log.Info("Card tokenization completed", zap.String("request_id", resp.GetRequestId()), zap.Bool("success", resp.GetSuccess()))
 	return gsresponse.Success(resp)
 }
 
@@ -65,14 +94,19 @@ func (s *Service) GetCardPayoutStatus(ctx context.Context, req *mntxv1.GetCardPa
 }
 
 func (s *Service) handleGetCardPayoutStatus(_ context.Context, req *mntxv1.GetCardPayoutStatusRequest) gsresponse.Responder[mntxv1.GetCardPayoutStatusResponse] {
+	log := s.logger.Named("card_payout_status")
+	log.Info("Get card payout status request received", zap.String("payout_id", strings.TrimSpace(req.GetPayoutId())))
 	if s.card == nil {
+		log.Warn("Card payout processor not initialised")
 		return gsresponse.Internal[mntxv1.GetCardPayoutStatusResponse](s.logger, mservice.MntxGateway, merrors.Internal("card payout processor not initialised"))
 	}
 
 	state, err := s.card.Status(context.Background(), req.GetPayoutId())
 	if err != nil {
+		log.Warn("Card payout status lookup failed", zap.Error(err))
 		return gsresponse.Auto[mntxv1.GetCardPayoutStatusResponse](s.logger, mservice.MntxGateway, err)
 	}
+	log.Info("Card payout status retrieved", zap.String("payout_id", state.GetPayoutId()), zap.String("status", state.GetStatus().String()))
 	return gsresponse.Success(&mntxv1.GetCardPayoutStatusResponse{Payout: state})
 }
 

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

@@ -0,0 +1,103 @@
+package gateway
+
+import (
+	"testing"
+
+	"github.com/tech/sendico/gateway/mntx/internal/service/monetix"
+	mntxv1 "github.com/tech/sendico/pkg/proto/gateway/mntx/v1"
+)
+
+func TestValidateCardPayoutRequest_Valid(t *testing.T) {
+	cfg := testMonetixConfig()
+	req := validCardPayoutRequest()
+	if err := validateCardPayoutRequest(req, cfg); err != nil {
+		t.Fatalf("expected no error, got %v", err)
+	}
+}
+
+func TestValidateCardPayoutRequest_Errors(t *testing.T) {
+	baseCfg := testMonetixConfig()
+	cases := []struct {
+		name     string
+		mutate   func(*mntxv1.CardPayoutRequest)
+		config   func(monetix.Config) monetix.Config
+		expected string
+	}{
+		{
+			name:     "missing_payout_id",
+			mutate:   func(r *mntxv1.CardPayoutRequest) { r.PayoutId = "" },
+			expected: "missing_payout_id",
+		},
+		{
+			name:     "missing_customer_id",
+			mutate:   func(r *mntxv1.CardPayoutRequest) { r.CustomerId = "" },
+			expected: "missing_customer_id",
+		},
+		{
+			name:     "missing_customer_ip",
+			mutate:   func(r *mntxv1.CardPayoutRequest) { r.CustomerIp = "" },
+			expected: "missing_customer_ip",
+		},
+		{
+			name:     "invalid_amount",
+			mutate:   func(r *mntxv1.CardPayoutRequest) { r.AmountMinor = 0 },
+			expected: "invalid_amount",
+		},
+		{
+			name:     "missing_currency",
+			mutate:   func(r *mntxv1.CardPayoutRequest) { r.Currency = "" },
+			expected: "missing_currency",
+		},
+		{
+			name:   "unsupported_currency",
+			mutate: func(r *mntxv1.CardPayoutRequest) { r.Currency = "EUR" },
+			config: func(cfg monetix.Config) monetix.Config {
+				cfg.AllowedCurrencies = []string{"USD"}
+				return cfg
+			},
+			expected: "unsupported_currency",
+		},
+		{
+			name:     "missing_card_pan",
+			mutate:   func(r *mntxv1.CardPayoutRequest) { r.CardPan = "" },
+			expected: "missing_card_pan",
+		},
+		{
+			name:     "missing_card_holder",
+			mutate:   func(r *mntxv1.CardPayoutRequest) { r.CardHolder = "" },
+			expected: "missing_card_holder",
+		},
+		{
+			name:     "invalid_expiry_month",
+			mutate:   func(r *mntxv1.CardPayoutRequest) { r.CardExpMonth = 13 },
+			expected: "invalid_expiry_month",
+		},
+		{
+			name:     "invalid_expiry_year",
+			mutate:   func(r *mntxv1.CardPayoutRequest) { r.CardExpYear = 0 },
+			expected: "invalid_expiry_year",
+		},
+		{
+			name:   "missing_customer_country_when_required",
+			mutate: func(r *mntxv1.CardPayoutRequest) { r.CustomerCountry = "" },
+			config: func(cfg monetix.Config) monetix.Config {
+				cfg.RequireCustomerAddress = true
+				return cfg
+			},
+			expected: "missing_customer_country",
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			req := validCardPayoutRequest()
+			tc.mutate(req)
+			cfg := baseCfg
+			if tc.config != nil {
+				cfg = tc.config(cfg)
+			}
+			err := validateCardPayoutRequest(req, cfg)
+			requireReason(t, err, tc.expected)
+		})
+	}
+}

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

@@ -45,14 +45,20 @@ func (p *cardPayoutProcessor) Submit(ctx context.Context, req *mntxv1.CardPayout
 	if p == nil {
 		return nil, merrors.Internal("card payout processor not initialised")
 	}
+	p.logger.Info("Submitting card payout",
+		zap.String("payout_id", strings.TrimSpace(req.GetPayoutId())),
+		zap.String("customer_id", strings.TrimSpace(req.GetCustomerId())),
+		zap.Int64("amount_minor", req.GetAmountMinor()),
+		zap.String("currency", strings.ToUpper(strings.TrimSpace(req.GetCurrency()))),
+	)
 	if strings.TrimSpace(p.config.BaseURL) == "" || strings.TrimSpace(p.config.SecretKey) == "" {
-		p.logger.Warn("monetix configuration is incomplete for payout submission")
+		p.logger.Warn("Monetix configuration is incomplete for payout submission")
 		return nil, merrors.Internal("monetix configuration is incomplete")
 	}
 
 	req = sanitizeCardPayoutRequest(req)
 	if err := validateCardPayoutRequest(req, p.config); err != nil {
-		p.logger.Warn("card payout validation failed",
+		p.logger.Warn("Card payout validation failed",
 			zap.String("payout_id", req.GetPayoutId()),
 			zap.String("customer_id", req.GetCustomerId()),
 			zap.Error(err),
@@ -65,7 +71,7 @@ func (p *cardPayoutProcessor) Submit(ctx context.Context, req *mntxv1.CardPayout
 		projectID = p.config.ProjectID
 	}
 	if projectID == 0 {
-		p.logger.Warn("monetix project_id is not configured", zap.String("payout_id", req.GetPayoutId()))
+		p.logger.Warn("Monetix project_id is not configured", zap.String("payout_id", req.GetPayoutId()))
 		return nil, merrors.Internal("monetix project_id is not configured")
 	}
 
@@ -95,7 +101,7 @@ func (p *cardPayoutProcessor) Submit(ctx context.Context, req *mntxv1.CardPayout
 		state.ProviderMessage = err.Error()
 		state.UpdatedAt = timestamppb.New(p.clock.Now())
 		p.store.Save(state)
-		p.logger.Warn("monetix payout submission failed",
+		p.logger.Warn("Monetix payout submission failed",
 			zap.String("payout_id", req.GetPayoutId()),
 			zap.String("customer_id", req.GetCustomerId()),
 			zap.Error(err),
@@ -122,6 +128,13 @@ func (p *cardPayoutProcessor) Submit(ctx context.Context, req *mntxv1.CardPayout
 		ErrorMessage:      result.ErrorMessage,
 	}
 
+	p.logger.Info("Card payout submission stored",
+		zap.String("payout_id", state.GetPayoutId()),
+		zap.String("status", state.GetStatus().String()),
+		zap.Bool("accepted", result.Accepted),
+		zap.String("provider_request_id", result.ProviderRequestID),
+	)
+
 	return resp, nil
 }
 
@@ -129,14 +142,20 @@ func (p *cardPayoutProcessor) SubmitToken(ctx context.Context, req *mntxv1.CardT
 	if p == nil {
 		return nil, merrors.Internal("card payout processor not initialised")
 	}
+	p.logger.Info("Submitting card token payout",
+		zap.String("payout_id", strings.TrimSpace(req.GetPayoutId())),
+		zap.String("customer_id", strings.TrimSpace(req.GetCustomerId())),
+		zap.Int64("amount_minor", req.GetAmountMinor()),
+		zap.String("currency", strings.ToUpper(strings.TrimSpace(req.GetCurrency()))),
+	)
 	if strings.TrimSpace(p.config.BaseURL) == "" || strings.TrimSpace(p.config.SecretKey) == "" {
-		p.logger.Warn("monetix configuration is incomplete for token payout submission")
+		p.logger.Warn("Monetix configuration is incomplete for token payout submission")
 		return nil, merrors.Internal("monetix configuration is incomplete")
 	}
 
 	req = sanitizeCardTokenPayoutRequest(req)
 	if err := validateCardTokenPayoutRequest(req, p.config); err != nil {
-		p.logger.Warn("card token payout validation failed",
+		p.logger.Warn("Card token payout validation failed",
 			zap.String("payout_id", req.GetPayoutId()),
 			zap.String("customer_id", req.GetCustomerId()),
 			zap.Error(err),
@@ -149,7 +168,7 @@ func (p *cardPayoutProcessor) SubmitToken(ctx context.Context, req *mntxv1.CardT
 		projectID = p.config.ProjectID
 	}
 	if projectID == 0 {
-		p.logger.Warn("monetix project_id is not configured", zap.String("payout_id", req.GetPayoutId()))
+		p.logger.Warn("Monetix project_id is not configured", zap.String("payout_id", req.GetPayoutId()))
 		return nil, merrors.Internal("monetix project_id is not configured")
 	}
 
@@ -179,7 +198,7 @@ func (p *cardPayoutProcessor) SubmitToken(ctx context.Context, req *mntxv1.CardT
 		state.ProviderMessage = err.Error()
 		state.UpdatedAt = timestamppb.New(p.clock.Now())
 		p.store.Save(state)
-		p.logger.Warn("monetix token payout submission failed",
+		p.logger.Warn("Monetix token payout submission failed",
 			zap.String("payout_id", req.GetPayoutId()),
 			zap.String("customer_id", req.GetCustomerId()),
 			zap.Error(err),
@@ -206,6 +225,13 @@ func (p *cardPayoutProcessor) SubmitToken(ctx context.Context, req *mntxv1.CardT
 		ErrorMessage:      result.ErrorMessage,
 	}
 
+	p.logger.Info("Card token payout submission stored",
+		zap.String("payout_id", state.GetPayoutId()),
+		zap.String("status", state.GetStatus().String()),
+		zap.Bool("accepted", result.Accepted),
+		zap.String("provider_request_id", result.ProviderRequestID),
+	)
+
 	return resp, nil
 }
 
@@ -213,9 +239,13 @@ func (p *cardPayoutProcessor) Tokenize(ctx context.Context, req *mntxv1.CardToke
 	if p == nil {
 		return nil, merrors.Internal("card payout processor not initialised")
 	}
+	p.logger.Info("Submitting card tokenization",
+		zap.String("request_id", strings.TrimSpace(req.GetRequestId())),
+		zap.String("customer_id", strings.TrimSpace(req.GetCustomerId())),
+	)
 	cardInput, err := validateCardTokenizeRequest(req, p.config)
 	if err != nil {
-		p.logger.Warn("card tokenization validation failed",
+		p.logger.Warn("Card tokenization validation failed",
 			zap.String("request_id", req.GetRequestId()),
 			zap.String("customer_id", req.GetCustomerId()),
 			zap.Error(err),
@@ -228,7 +258,7 @@ func (p *cardPayoutProcessor) Tokenize(ctx context.Context, req *mntxv1.CardToke
 		projectID = p.config.ProjectID
 	}
 	if projectID == 0 {
-		p.logger.Warn("monetix project_id is not configured", zap.String("request_id", req.GetRequestId()))
+		p.logger.Warn("Monetix project_id is not configured", zap.String("request_id", req.GetRequestId()))
 		return nil, merrors.Internal("monetix project_id is not configured")
 	}
 
@@ -238,7 +268,7 @@ func (p *cardPayoutProcessor) Tokenize(ctx context.Context, req *mntxv1.CardToke
 	apiReq := buildCardTokenizeRequest(projectID, req, cardInput)
 	result, err := client.CreateCardTokenization(ctx, apiReq)
 	if err != nil {
-		p.logger.Warn("monetix tokenization request failed",
+		p.logger.Warn("Monetix tokenization request failed",
 			zap.String("request_id", req.GetRequestId()),
 			zap.String("customer_id", req.GetCustomerId()),
 			zap.Error(err),
@@ -258,6 +288,12 @@ func (p *cardPayoutProcessor) Tokenize(ctx context.Context, req *mntxv1.CardToke
 	resp.ExpiryYear = result.ExpiryYear
 	resp.CardBrand = result.CardBrand
 
+	p.logger.Info("Card tokenization completed",
+		zap.String("request_id", resp.GetRequestId()),
+		zap.Bool("success", resp.GetSuccess()),
+		zap.String("provider_request_id", result.ProviderRequestID),
+	)
+
 	return resp, nil
 }
 
@@ -267,16 +303,18 @@ func (p *cardPayoutProcessor) Status(_ context.Context, payoutID string) (*mntxv
 	}
 
 	id := strings.TrimSpace(payoutID)
+	p.logger.Info("Card payout status requested", zap.String("payout_id", id))
 	if id == "" {
-		p.logger.Warn("payout status requested with empty payout_id")
+		p.logger.Warn("Payout status requested with empty payout_id")
 		return nil, merrors.InvalidArgument("payout_id is required", "payout_id")
 	}
 
 	state, ok := p.store.Get(id)
 	if !ok || state == nil {
-		p.logger.Warn("payout status not found", zap.String("payout_id", id))
+		p.logger.Warn("Payout status not found", zap.String("payout_id", id))
 		return nil, merrors.NoData("payout not found")
 	}
+	p.logger.Info("Card payout status resolved", zap.String("payout_id", state.GetPayoutId()), zap.String("status", state.GetStatus().String()))
 	return state, nil
 }
 
@@ -284,18 +322,19 @@ func (p *cardPayoutProcessor) ProcessCallback(ctx context.Context, payload []byt
 	if p == nil {
 		return http.StatusInternalServerError, merrors.Internal("card payout processor not initialised")
 	}
+	p.logger.Debug("Processing Monetix callback", zap.Int("payload_bytes", len(payload)))
 	if len(payload) == 0 {
-		p.logger.Warn("received empty Monetix callback payload")
+		p.logger.Warn("Received empty Monetix callback payload")
 		return http.StatusBadRequest, merrors.InvalidArgument("callback body is empty")
 	}
 	if strings.TrimSpace(p.config.SecretKey) == "" {
-		p.logger.Warn("monetix secret key is not configured; cannot verify callback")
+		p.logger.Warn("Monetix secret key is not configured; cannot verify callback")
 		return http.StatusInternalServerError, merrors.Internal("monetix secret key is not configured")
 	}
 
 	var cb monetixCallback
 	if err := json.Unmarshal(payload, &cb); err != nil {
-		p.logger.Warn("failed to unmarshal Monetix callback", zap.Error(err))
+		p.logger.Warn("Failed to unmarshal Monetix callback", zap.Error(err))
 		return http.StatusBadRequest, err
 	}
 
@@ -318,7 +357,7 @@ func (p *cardPayoutProcessor) ProcessCallback(ctx context.Context, payload []byt
 	p.emitCardPayoutEvent(state)
 	monetix.ObserveCallback(statusLabel)
 
-	p.logger.Info("Monetix payout callback processed",
+	p.logger.Debug("Monetix payout callback processed",
 		zap.String("payout_id", state.GetPayoutId()),
 		zap.String("status", statusLabel),
 		zap.String("provider_code", state.GetProviderCode()),
@@ -337,16 +376,16 @@ func (p *cardPayoutProcessor) emitCardPayoutEvent(state *mntxv1.CardPayoutState)
 	event := &mntxv1.CardPayoutStatusChangedEvent{Payout: state}
 	payload, err := protojson.Marshal(event)
 	if err != nil {
-		p.logger.Warn("failed to marshal payout callback event", zap.Error(err))
+		p.logger.Warn("Failed to marshal payout callback event", zap.Error(err))
 		return
 	}
 
 	env := messaging.CreateEnvelope(string(mservice.MntxGateway), model.NewNotification(mservice.MntxGateway, nm.NAUpdated))
 	if _, err := env.Wrap(payload); err != nil {
-		p.logger.Warn("failed to wrap payout callback event payload", zap.Error(err))
+		p.logger.Warn("Failed to wrap payout callback event payload", zap.Error(err))
 		return
 	}
 	if err := p.producer.SendMessage(env); err != nil {
-		p.logger.Warn("failed to publish payout callback event", zap.Error(err))
+		p.logger.Warn("Failed to publish payout callback event", zap.Error(err))
 	}
 }

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

@@ -0,0 +1,149 @@
+package gateway
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"errors"
+	"io"
+	"net/http"
+	"testing"
+	"time"
+
+	"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"
+	"go.uber.org/zap"
+	"google.golang.org/protobuf/types/known/timestamppb"
+)
+
+type roundTripperFunc func(*http.Request) (*http.Response, error)
+
+func (f roundTripperFunc) RoundTrip(r *http.Request) (*http.Response, error) {
+	return f(r)
+}
+
+type staticClock struct {
+	now time.Time
+}
+
+func (s staticClock) Now() time.Time {
+	return s.now
+}
+
+func TestCardPayoutProcessor_Submit_Success(t *testing.T) {
+	cfg := monetix.Config{
+		BaseURL:           "https://monetix.test",
+		SecretKey:         "secret",
+		ProjectID:         99,
+		AllowedCurrencies: []string{"RUB"},
+	}
+
+	existingCreated := timestamppb.New(time.Date(2020, 2, 3, 0, 0, 0, 0, time.UTC))
+	store := newCardPayoutStore()
+	store.Save(&mntxv1.CardPayoutState{
+		PayoutId:  "payout-1",
+		CreatedAt: existingCreated,
+	})
+
+	httpClient := &http.Client{
+		Transport: roundTripperFunc(func(r *http.Request) (*http.Response, error) {
+			resp := monetix.APIResponse{}
+			resp.Operation.RequestID = "req-123"
+			body, _ := json.Marshal(resp)
+			return &http.Response{
+				StatusCode: http.StatusOK,
+				Body:       io.NopCloser(bytes.NewReader(body)),
+				Header:     http.Header{"Content-Type": []string{"application/json"}},
+			}, nil
+		}),
+	}
+
+	now := time.Date(2024, 1, 1, 12, 0, 0, 0, time.UTC)
+	processor := newCardPayoutProcessor(zap.NewNop(), cfg, staticClock{now: now}, store, httpClient, nil)
+
+	req := validCardPayoutRequest()
+	req.ProjectId = 0
+
+	resp, err := processor.Submit(context.Background(), req)
+	if err != nil {
+		t.Fatalf("expected no error, got %v", err)
+	}
+	if !resp.GetAccepted() {
+		t.Fatalf("expected accepted payout response")
+	}
+	if resp.GetPayout().GetProjectId() != cfg.ProjectID {
+		t.Fatalf("expected project id %d, got %d", cfg.ProjectID, resp.GetPayout().GetProjectId())
+	}
+	if resp.GetPayout().GetStatus() != mntxv1.PayoutStatus_PAYOUT_STATUS_PENDING {
+		t.Fatalf("expected pending status, got %v", resp.GetPayout().GetStatus())
+	}
+	if !resp.GetPayout().GetCreatedAt().AsTime().Equal(existingCreated.AsTime()) {
+		t.Fatalf("expected created_at preserved, got %v", resp.GetPayout().GetCreatedAt().AsTime())
+	}
+
+	stored, ok := store.Get(req.GetPayoutId())
+	if !ok || stored == nil {
+		t.Fatalf("expected payout state stored")
+	}
+	if stored.GetProviderPaymentId() == "" {
+		t.Fatalf("expected provider payment id")
+	}
+}
+
+func TestCardPayoutProcessor_Submit_MissingConfig(t *testing.T) {
+	cfg := monetix.Config{
+		AllowedCurrencies: []string{"RUB"},
+	}
+	processor := newCardPayoutProcessor(zap.NewNop(), cfg, clockpkg.NewSystem(), newCardPayoutStore(), &http.Client{}, nil)
+
+	_, err := processor.Submit(context.Background(), validCardPayoutRequest())
+	if err == nil {
+		t.Fatalf("expected error")
+	}
+	if !errors.Is(err, merrors.ErrInternal) {
+		t.Fatalf("expected internal error, got %v", err)
+	}
+}
+
+func TestCardPayoutProcessor_ProcessCallback(t *testing.T) {
+	cfg := monetix.Config{
+		SecretKey:         "secret",
+		StatusSuccess:     "success",
+		StatusProcessing:  "processing",
+		AllowedCurrencies: []string{"RUB"},
+	}
+	store := newCardPayoutStore()
+	processor := newCardPayoutProcessor(zap.NewNop(), cfg, staticClock{now: time.Date(2024, 1, 2, 3, 4, 5, 0, time.UTC)}, store, &http.Client{}, nil)
+
+	cb := baseCallback()
+	cb.Payment.Sum.Currency = "RUB"
+	cb.Signature = ""
+	sig, err := monetix.SignPayload(cb, cfg.SecretKey)
+	if err != nil {
+		t.Fatalf("failed to sign callback: %v", err)
+	}
+	cb.Signature = sig
+
+	payload, err := json.Marshal(cb)
+	if err != nil {
+		t.Fatalf("failed to marshal callback: %v", err)
+	}
+
+	status, err := processor.ProcessCallback(context.Background(), payload)
+	if err != nil {
+		t.Fatalf("expected no error, got %v", err)
+	}
+	if status != http.StatusOK {
+		t.Fatalf("expected status ok, got %d", status)
+	}
+
+	state, ok := store.Get(cb.Payment.ID)
+	if !ok || state == nil {
+		t.Fatalf("expected payout state stored")
+	}
+	if state.GetStatus() != mntxv1.PayoutStatus_PAYOUT_STATUS_PROCESSED {
+		t.Fatalf("expected processed status, got %v", state.GetStatus())
+	}
+}

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

@@ -0,0 +1,93 @@
+package gateway
+
+import (
+	"testing"
+
+	"github.com/tech/sendico/gateway/mntx/internal/service/monetix"
+	mntxv1 "github.com/tech/sendico/pkg/proto/gateway/mntx/v1"
+)
+
+func TestValidateCardTokenPayoutRequest_Valid(t *testing.T) {
+	cfg := testMonetixConfig()
+	req := validCardTokenPayoutRequest()
+	if err := validateCardTokenPayoutRequest(req, cfg); err != nil {
+		t.Fatalf("expected no error, got %v", err)
+	}
+}
+
+func TestValidateCardTokenPayoutRequest_Errors(t *testing.T) {
+	baseCfg := testMonetixConfig()
+	cases := []struct {
+		name     string
+		mutate   func(*mntxv1.CardTokenPayoutRequest)
+		config   func(monetix.Config) monetix.Config
+		expected string
+	}{
+		{
+			name:     "missing_payout_id",
+			mutate:   func(r *mntxv1.CardTokenPayoutRequest) { r.PayoutId = "" },
+			expected: "missing_payout_id",
+		},
+		{
+			name:     "missing_customer_id",
+			mutate:   func(r *mntxv1.CardTokenPayoutRequest) { r.CustomerId = "" },
+			expected: "missing_customer_id",
+		},
+		{
+			name:     "missing_customer_ip",
+			mutate:   func(r *mntxv1.CardTokenPayoutRequest) { r.CustomerIp = "" },
+			expected: "missing_customer_ip",
+		},
+		{
+			name:     "invalid_amount",
+			mutate:   func(r *mntxv1.CardTokenPayoutRequest) { r.AmountMinor = 0 },
+			expected: "invalid_amount",
+		},
+		{
+			name:     "missing_currency",
+			mutate:   func(r *mntxv1.CardTokenPayoutRequest) { r.Currency = "" },
+			expected: "missing_currency",
+		},
+		{
+			name:   "unsupported_currency",
+			mutate: func(r *mntxv1.CardTokenPayoutRequest) { r.Currency = "EUR" },
+			config: func(cfg monetix.Config) monetix.Config {
+				cfg.AllowedCurrencies = []string{"USD"}
+				return cfg
+			},
+			expected: "unsupported_currency",
+		},
+		{
+			name:     "missing_card_token",
+			mutate:   func(r *mntxv1.CardTokenPayoutRequest) { r.CardToken = "" },
+			expected: "missing_card_token",
+		},
+		{
+			name:   "missing_customer_city_when_required",
+			mutate: func(r *mntxv1.CardTokenPayoutRequest) {
+				r.CustomerCountry = "US"
+				r.CustomerCity = ""
+				r.CustomerAddress = "Main St"
+				r.CustomerZip = "12345"
+			},
+			config: func(cfg monetix.Config) monetix.Config {
+				cfg.RequireCustomerAddress = true
+				return cfg
+			},
+			expected: "missing_customer_city",
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			req := validCardTokenPayoutRequest()
+			tc.mutate(req)
+			cfg := baseCfg
+			if tc.config != nil {
+				cfg = tc.config(cfg)
+			}
+			err := validateCardTokenPayoutRequest(req, cfg)
+			requireReason(t, err, tc.expected)
+		})
+	}
+}

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

@@ -0,0 +1,76 @@
+package gateway
+
+import (
+	"testing"
+	"time"
+
+	mntxv1 "github.com/tech/sendico/pkg/proto/gateway/mntx/v1"
+)
+
+func TestValidateCardTokenizeRequest_ValidTopLevel(t *testing.T) {
+	cfg := testMonetixConfig()
+	req := validCardTokenizeRequest()
+	if _, err := validateCardTokenizeRequest(req, cfg); err != nil {
+		t.Fatalf("expected no error, got %v", err)
+	}
+}
+
+func TestValidateCardTokenizeRequest_ValidNestedCard(t *testing.T) {
+	cfg := testMonetixConfig()
+	req := validCardTokenizeRequest()
+	req.Card = &mntxv1.CardDetails{
+		Pan:        "4111111111111111",
+		ExpMonth:   req.CardExpMonth,
+		ExpYear:    req.CardExpYear,
+		CardHolder: req.CardHolder,
+		Cvv:        req.CardCvv,
+	}
+	req.CardPan = ""
+	req.CardExpMonth = 0
+	req.CardExpYear = 0
+	req.CardHolder = ""
+	req.CardCvv = ""
+
+	if _, err := validateCardTokenizeRequest(req, cfg); err != nil {
+		t.Fatalf("expected no error, got %v", err)
+	}
+}
+
+func TestValidateCardTokenizeRequest_Expired(t *testing.T) {
+	cfg := testMonetixConfig()
+	req := validCardTokenizeRequest()
+	now := time.Now().UTC()
+	req.CardExpMonth = uint32(now.Month())
+	req.CardExpYear = uint32(now.Year() - 1)
+
+	_, err := validateCardTokenizeRequest(req, cfg)
+	requireReason(t, err, "expired_card")
+}
+
+func TestValidateCardTokenizeRequest_MissingCvv(t *testing.T) {
+	cfg := testMonetixConfig()
+	req := validCardTokenizeRequest()
+	req.CardCvv = ""
+
+	_, err := validateCardTokenizeRequest(req, cfg)
+	requireReason(t, err, "missing_cvv")
+}
+
+func TestValidateCardTokenizeRequest_MissingCardPan(t *testing.T) {
+	cfg := testMonetixConfig()
+	req := validCardTokenizeRequest()
+	req.CardPan = ""
+
+	_, err := validateCardTokenizeRequest(req, cfg)
+	requireReason(t, err, "missing_card_pan")
+}
+
+func TestValidateCardTokenizeRequest_AddressRequired(t *testing.T) {
+	cfg := testMonetixConfig()
+	cfg.RequireCustomerAddress = true
+	req := validCardTokenizeRequest()
+	req.CustomerCountry = ""
+
+	_, err := validateCardTokenizeRequest(req, cfg)
+	requireReason(t, err, "missing_customer_country")
+}

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

@@ -9,6 +9,7 @@ import (
 	"github.com/tech/sendico/pkg/merrors"
 	"github.com/tech/sendico/pkg/mservice"
 	mntxv1 "github.com/tech/sendico/pkg/proto/gateway/mntx/v1"
+	"go.uber.org/zap"
 )
 
 func (s *Service) GetPayout(ctx context.Context, req *mntxv1.GetPayoutRequest) (*mntxv1.GetPayoutResponse, error) {
@@ -17,14 +18,19 @@ func (s *Service) GetPayout(ctx context.Context, req *mntxv1.GetPayoutRequest) (
 
 func (s *Service) handleGetPayout(_ context.Context, req *mntxv1.GetPayoutRequest) gsresponse.Responder[mntxv1.GetPayoutResponse] {
 	ref := strings.TrimSpace(req.GetPayoutRef())
+	log := s.logger.Named("payout")
+	log.Info("Get payout request received", zap.String("payout_ref", ref))
 	if ref == "" {
+		log.Warn("Get payout request missing payout_ref")
 		return gsresponse.InvalidArgument[mntxv1.GetPayoutResponse](s.logger, mservice.MntxGateway, merrors.InvalidArgument("payout_ref is required", "payout_ref"))
 	}
 
 	payout, ok := s.store.Get(ref)
 	if !ok {
+		log.Warn("Payout not found", zap.String("payout_ref", ref))
 		return gsresponse.NotFound[mntxv1.GetPayoutResponse](s.logger, mservice.MntxGateway, merrors.NoData(fmt.Sprintf("payout %s not found", ref)))
 	}
 
+	log.Info("Payout retrieved", zap.String("payout_ref", ref), zap.String("status", payout.GetStatus().String()))
 	return gsresponse.Success(&mntxv1.GetPayoutResponse{Payout: payout})
 }

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

@@ -22,8 +22,17 @@ func (s *Service) SubmitPayout(ctx context.Context, req *mntxv1.SubmitPayoutRequ
 }
 
 func (s *Service) handleSubmitPayout(_ context.Context, req *mntxv1.SubmitPayoutRequest) gsresponse.Responder[mntxv1.SubmitPayoutResponse] {
+	log := s.logger.Named("payout")
+	log.Info("Submit payout request received",
+		zap.String("idempotency_key", strings.TrimSpace(req.GetIdempotencyKey())),
+		zap.String("organization_ref", strings.TrimSpace(req.GetOrganizationRef())),
+		zap.String("currency", strings.TrimSpace(req.GetAmount().GetCurrency())),
+		zap.String("amount", strings.TrimSpace(req.GetAmount().GetAmount())),
+	)
+
 	payout, err := s.buildPayout(req)
 	if err != nil {
+		log.Warn("Submit payout validation failed", zap.Error(err))
 		return gsresponse.Auto[mntxv1.SubmitPayoutResponse](s.logger, mservice.MntxGateway, err)
 	}
 
@@ -31,6 +40,7 @@ func (s *Service) handleSubmitPayout(_ context.Context, req *mntxv1.SubmitPayout
 	s.emitEvent(payout, nm.NAPending)
 	go s.completePayout(payout, strings.TrimSpace(req.GetSimulatedFailureReason()))
 
+	log.Info("Payout accepted", zap.String("payout_ref", payout.GetPayoutRef()), zap.String("status", payout.GetStatus().String()))
 	return gsresponse.Success(&mntxv1.SubmitPayoutResponse{Payout: payout})
 }
 
@@ -79,6 +89,7 @@ func (s *Service) buildPayout(req *mntxv1.SubmitPayoutRequest) (*mntxv1.Payout,
 }
 
 func (s *Service) completePayout(original *mntxv1.Payout, simulatedFailure string) {
+	log := s.logger.Named("payout")
 	outcome := clonePayout(original)
 	if outcome == nil {
 		return
@@ -95,6 +106,7 @@ func (s *Service) completePayout(original *mntxv1.Payout, simulatedFailure strin
 		observePayoutError(simulatedFailure, outcome.Amount)
 		s.store.Save(outcome)
 		s.emitEvent(outcome, nm.NAUpdated)
+		log.Info("Payout completed", zap.String("payout_ref", outcome.GetPayoutRef()), zap.String("status", outcome.GetStatus().String()), zap.String("failure_reason", simulatedFailure))
 		return
 	}
 
@@ -102,6 +114,7 @@ func (s *Service) completePayout(original *mntxv1.Payout, simulatedFailure strin
 	observePayoutSuccess(outcome.Amount)
 	s.store.Save(outcome)
 	s.emitEvent(outcome, nm.NAUpdated)
+	log.Info("Payout completed", zap.String("payout_ref", outcome.GetPayoutRef()), zap.String("status", outcome.GetStatus().String()))
 }
 
 func (s *Service) emitEvent(payout *mntxv1.Payout, action nm.NotificationAction) {
@@ -111,18 +124,18 @@ func (s *Service) emitEvent(payout *mntxv1.Payout, action nm.NotificationAction)
 
 	payload, err := protojson.Marshal(&mntxv1.PayoutStatusChangedEvent{Payout: payout})
 	if err != nil {
-		s.logger.Warn("failed to marshal payout event", zapError(err))
+		s.logger.Warn("Failed to marshal payout event", zapError(err))
 		return
 	}
 
 	env := messaging.CreateEnvelope(string(mservice.MntxGateway), model.NewNotification(mservice.MntxGateway, action))
 	if _, err := env.Wrap(payload); err != nil {
-		s.logger.Warn("failed to wrap payout event payload", zapError(err))
+		s.logger.Warn("Failed to wrap payout event payload", zapError(err))
 		return
 	}
 
 	if err := s.producer.SendMessage(env); err != nil {
-		s.logger.Warn("failed to publish payout event", zapError(err))
+		s.logger.Warn("Failed to publish payout event", zapError(err))
 	}
 }
 

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

@@ -14,6 +14,7 @@ import (
 	"github.com/tech/sendico/pkg/mlogger"
 	"github.com/tech/sendico/pkg/mservice"
 	mntxv1 "github.com/tech/sendico/pkg/proto/gateway/mntx/v1"
+	"go.uber.org/zap"
 	"google.golang.org/grpc"
 )
 
@@ -97,9 +98,19 @@ func (s *Service) Register(router routers.GRPC) error {
 }
 
 func executeUnary[TReq any, TResp any](ctx context.Context, svc *Service, method string, handler func(context.Context, *TReq) gsresponse.Responder[TResp], req *TReq) (*TResp, error) {
+	log := svc.logger.Named("rpc")
+	log.Info("RPC request started", zap.String("method", method))
+
 	start := svc.clock.Now()
 	resp, err := gsresponse.Unary(svc.logger, mservice.MntxGateway, handler)(ctx, req)
-	observeRPC(method, err, svc.clock.Now().Sub(start))
+	duration := svc.clock.Now().Sub(start)
+	observeRPC(method, err, duration)
+
+	if err != nil {
+		log.Warn("RPC request failed", zap.String("method", method), zap.Duration("duration", duration), zap.Error(err))
+	} else {
+		log.Info("RPC request completed", zap.String("method", method), zap.Duration("duration", duration))
+	}
 	return resp, err
 }
 

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

@@ -0,0 +1,84 @@
+package gateway
+
+import (
+	"errors"
+	"testing"
+	"time"
+
+	"github.com/tech/sendico/gateway/mntx/internal/service/monetix"
+	"github.com/tech/sendico/pkg/merrors"
+	mntxv1 "github.com/tech/sendico/pkg/proto/gateway/mntx/v1"
+)
+
+func requireReason(t *testing.T, err error, reason string) {
+	t.Helper()
+	if err == nil {
+		t.Fatalf("expected error")
+	}
+	if !errors.Is(err, merrors.ErrInvalidArg) {
+		t.Fatalf("expected invalid argument error, got %v", err)
+	}
+	reasoned, ok := err.(payoutFailure)
+	if !ok {
+		t.Fatalf("expected payout failure reason, got %T", err)
+	}
+	if reasoned.Reason() != reason {
+		t.Fatalf("expected reason %q, got %q", reason, reasoned.Reason())
+	}
+}
+
+func testMonetixConfig() monetix.Config {
+	return monetix.Config{
+		AllowedCurrencies: []string{"RUB", "USD"},
+	}
+}
+
+func validCardPayoutRequest() *mntxv1.CardPayoutRequest {
+	return &mntxv1.CardPayoutRequest{
+		PayoutId:          "payout-1",
+		CustomerId:        "cust-1",
+		CustomerFirstName: "Jane",
+		CustomerLastName:  "Doe",
+		CustomerIp:        "203.0.113.10",
+		AmountMinor:       1500,
+		Currency:          "RUB",
+		CardPan:           "4111111111111111",
+		CardHolder:        "JANE DOE",
+		CardExpMonth:      12,
+		CardExpYear:       2035,
+	}
+}
+
+func validCardTokenPayoutRequest() *mntxv1.CardTokenPayoutRequest {
+	return &mntxv1.CardTokenPayoutRequest{
+		PayoutId:          "payout-1",
+		CustomerId:        "cust-1",
+		CustomerFirstName: "Jane",
+		CustomerLastName:  "Doe",
+		CustomerIp:        "203.0.113.11",
+		AmountMinor:       2500,
+		Currency:          "USD",
+		CardToken:         "tok_123",
+	}
+}
+
+func validCardTokenizeRequest() *mntxv1.CardTokenizeRequest {
+	month, year := futureExpiry()
+	return &mntxv1.CardTokenizeRequest{
+		RequestId:         "req-1",
+		CustomerId:        "cust-1",
+		CustomerFirstName: "Jane",
+		CustomerLastName:  "Doe",
+		CustomerIp:        "203.0.113.12",
+		CardPan:           "4111111111111111",
+		CardHolder:        "JANE DOE",
+		CardCvv:           "123",
+		CardExpMonth:      month,
+		CardExpYear:       year,
+	}
+}
+
+func futureExpiry() (uint32, uint32) {
+	now := time.Now().UTC()
+	return uint32(now.Month()), uint32(now.Year() + 1)
+}

api/gateway/mntx/internal/service/monetix/client.go

@@ -2,10 +2,6 @@ package monetix
 
 import (
 	"context"
-	"crypto/hmac"
-	"crypto/sha256"
-	"encoding/hex"
-	"encoding/json"
 	"net/http"
 
 	"github.com/tech/sendico/pkg/mlogger"
@@ -45,21 +41,3 @@ func (c *Client) CreateCardTokenPayout(ctx context.Context, req CardTokenPayoutR
 func (c *Client) CreateCardTokenization(ctx context.Context, req CardTokenizeRequest) (*TokenizationResult, error) {
 	return c.sendTokenization(ctx, req)
 }
-
-func signPayload(payload any, secret string) (string, error) {
-	data, err := json.Marshal(payload)
-	if err != nil {
-		return "", err
-	}
-
-	h := hmac.New(sha256.New, []byte(secret))
-	if _, err := h.Write(data); err != nil {
-		return "", err
-	}
-	return hex.EncodeToString(h.Sum(nil)), nil
-}
-
-// SignPayload exposes signature calculation for callback verification.
-func SignPayload(payload any, secret string) (string, error) {
-	return signPayload(payload, secret)
-}

api/gateway/mntx/internal/service/monetix/mask_test.go

@@ -0,0 +1,23 @@
+package monetix
+
+import "testing"
+
+func TestMaskPAN(t *testing.T) {
+	cases := []struct {
+		input    string
+		expected string
+	}{
+		{input: "1234", expected: "****"},
+		{input: "1234567890", expected: "12******90"},
+		{input: "1234567890123456", expected: "123456******3456"},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.input, func(t *testing.T) {
+			got := MaskPAN(tc.input)
+			if got != tc.expected {
+				t.Fatalf("expected %q, got %q", tc.expected, got)
+			}
+		})
+	}
+}

api/gateway/mntx/internal/service/monetix/sender.go

@@ -24,7 +24,7 @@ func (c *Client) sendCardPayout(ctx context.Context, req CardPayoutRequest) (*Ca
 	maskedPAN := MaskPAN(req.Card.PAN)
 	return c.send(ctx, &req, "/v2/payment/card/payout",
 		func() {
-			c.logger.Info("dispatching Monetix card payout",
+			c.logger.Info("Dispatching Monetix card payout",
 				zap.String("payout_id", req.General.PaymentID),
 				zap.Int64("amount_minor", req.Payment.Amount),
 				zap.String("currency", req.Payment.Currency),
@@ -47,7 +47,7 @@ func (c *Client) sendCardPayout(ctx context.Context, req CardPayoutRequest) (*Ca
 func (c *Client) sendCardTokenPayout(ctx context.Context, req CardTokenPayoutRequest) (*CardPayoutSendResult, error) {
 	return c.send(ctx, &req, "/v2/payment/card/payout/token",
 		func() {
-			c.logger.Info("dispatching Monetix card token payout",
+			c.logger.Info("Dispatching Monetix card token payout",
 				zap.String("payout_id", req.General.PaymentID),
 				zap.Int64("amount_minor", req.Payment.Amount),
 				zap.String("currency", req.Payment.Currency),
@@ -101,7 +101,7 @@ func (c *Client) sendTokenization(ctx context.Context, req CardTokenizeRequest)
 	httpReq.Header.Set("Content-Type", "application/json")
 	httpReq.Header.Set("Accept", "application/json")
 
-	c.logger.Info("dispatching Monetix card tokenization",
+	c.logger.Info("Dispatching Monetix card tokenization",
 		zap.String("request_id", req.General.PaymentID),
 		zap.String("masked_pan", MaskPAN(req.Card.PAN)),
 	)
@@ -111,7 +111,7 @@ func (c *Client) sendTokenization(ctx context.Context, req CardTokenizeRequest)
 	duration := time.Since(start)
 	if err != nil {
 		observeRequest(outcomeNetworkError, duration)
-		c.logger.Warn("monetix tokenization request failed", zap.Error(err))
+		c.logger.Warn("Monetix tokenization request failed", zap.Error(err))
 		return nil, merrors.Internal("monetix tokenization request failed: " + err.Error())
 	}
 	defer resp.Body.Close()
@@ -133,7 +133,7 @@ func (c *Client) sendTokenization(ctx context.Context, req CardTokenizeRequest)
 	var apiResp APIResponse
 	if len(body) > 0 {
 		if err := json.Unmarshal(body, &apiResp); err != nil {
-			c.logger.Warn("failed to decode Monetix tokenization response", zap.String("request_id", req.General.PaymentID), zap.Int("status_code", resp.StatusCode), zap.Error(err))
+			c.logger.Warn("Failed to decode Monetix tokenization response", zap.String("request_id", req.General.PaymentID), zap.Int("status_code", resp.StatusCode), zap.Error(err))
 		} else {
 			var tokenData struct {
 				Token       string `json:"token"`
@@ -245,7 +245,7 @@ func (c *Client) send(ctx context.Context, req any, path string, dispatchLog fun
 	var apiResp APIResponse
 	if len(body) > 0 {
 		if err := json.Unmarshal(body, &apiResp); err != nil {
-			c.logger.Warn("failed to decode Monetix response", zap.Int("status_code", resp.StatusCode), zap.Error(err))
+			c.logger.Warn("Failed to decode Monetix response", zap.Int("status_code", resp.StatusCode), zap.Error(err))
 		}
 	}
 

api/gateway/mntx/internal/service/monetix/sender_test.go

@@ -0,0 +1,128 @@
+package monetix
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"io"
+	"net/http"
+	"strings"
+	"testing"
+
+	"go.uber.org/zap"
+)
+
+type roundTripperFunc func(*http.Request) (*http.Response, error)
+
+func (f roundTripperFunc) RoundTrip(r *http.Request) (*http.Response, error) {
+	return f(r)
+}
+
+func TestSendCardPayout_SignsPayload(t *testing.T) {
+	secret := "secret"
+	var captured CardPayoutRequest
+
+	httpClient := &http.Client{
+		Transport: roundTripperFunc(func(r *http.Request) (*http.Response, error) {
+			if r.URL.Path != "/v2/payment/card/payout" {
+				t.Fatalf("expected payout path, got %q", r.URL.Path)
+			}
+			body, _ := io.ReadAll(r.Body)
+			if err := json.Unmarshal(body, &captured); err != nil {
+				t.Fatalf("failed to decode request: %v", err)
+			}
+			resp := APIResponse{}
+			resp.Operation.RequestID = "req-1"
+			payload, _ := json.Marshal(resp)
+			return &http.Response{
+				StatusCode: http.StatusOK,
+				Body:       io.NopCloser(bytes.NewReader(payload)),
+				Header:     http.Header{"Content-Type": []string{"application/json"}},
+			}, nil
+		}),
+	}
+
+	cfg := Config{
+		BaseURL:   "https://monetix.test",
+		SecretKey: secret,
+	}
+	client := NewClient(cfg, httpClient, zap.NewNop())
+
+	req := CardPayoutRequest{
+		General: General{ProjectID: 1, PaymentID: "payout-1"},
+		Customer: Customer{
+			ID:        "cust-1",
+			FirstName: "Jane",
+			LastName:  "Doe",
+			IP:        "203.0.113.10",
+		},
+		Payment: Payment{Amount: 1000, Currency: "RUB"},
+		Card:    Card{PAN: "4111111111111111", Year: 2030, Month: 12, CardHolder: "JANE DOE"},
+	}
+
+	result, err := client.CreateCardPayout(context.Background(), req)
+	if err != nil {
+		t.Fatalf("expected no error, got %v", err)
+	}
+	if !result.Accepted {
+		t.Fatalf("expected accepted response")
+	}
+	if captured.General.Signature == "" {
+		t.Fatalf("expected signature in request")
+	}
+
+	signed := captured
+	signed.General.Signature = ""
+	expectedSig, err := SignPayload(signed, secret)
+	if err != nil {
+		t.Fatalf("failed to compute signature: %v", err)
+	}
+	if captured.General.Signature != expectedSig {
+		t.Fatalf("expected signature %q, got %q", expectedSig, captured.General.Signature)
+	}
+}
+
+func TestSendCardPayout_HTTPError(t *testing.T) {
+	httpClient := &http.Client{
+		Transport: roundTripperFunc(func(r *http.Request) (*http.Response, error) {
+			body := `{"code":"E100","message":"denied"}`
+			return &http.Response{
+				StatusCode: http.StatusBadRequest,
+				Body:       io.NopCloser(strings.NewReader(body)),
+				Header:     http.Header{"Content-Type": []string{"application/json"}},
+			}, nil
+		}),
+	}
+
+	cfg := Config{
+		BaseURL:   "https://monetix.test",
+		SecretKey: "secret",
+	}
+	client := NewClient(cfg, httpClient, zap.NewNop())
+
+	req := CardPayoutRequest{
+		General: General{ProjectID: 1, PaymentID: "payout-1"},
+		Customer: Customer{
+			ID:        "cust-1",
+			FirstName: "Jane",
+			LastName:  "Doe",
+			IP:        "203.0.113.10",
+		},
+		Payment: Payment{Amount: 1000, Currency: "RUB"},
+		Card:    Card{PAN: "4111111111111111", Year: 2030, Month: 12, CardHolder: "JANE DOE"},
+	}
+
+	result, err := client.CreateCardPayout(context.Background(), req)
+	if err != nil {
+		t.Fatalf("expected no error, got %v", err)
+	}
+	if result.Accepted {
+		t.Fatalf("expected rejected response")
+	}
+	if result.ErrorCode != "E100" {
+		t.Fatalf("expected error code E100, got %q", result.ErrorCode)
+	}
+	if result.ErrorMessage != "denied" {
+		t.Fatalf("expected error message denied, got %q", result.ErrorMessage)
+	}
+}

api/gateway/mntx/internal/service/monetix/signature.go

@@ -0,0 +1,112 @@
+package monetix
+
+import (
+	"bytes"
+	"crypto/hmac"
+	"crypto/sha512"
+	"encoding/base64"
+	"encoding/json"
+	"fmt"
+	"sort"
+	"strconv"
+	"strings"
+)
+
+func signPayload(payload any, secret string) (string, error) {
+	canonical, err := signaturePayloadString(payload)
+	if err != nil {
+		return "", err
+	}
+
+	mac := hmac.New(sha512.New, []byte(secret))
+	if _, err := mac.Write([]byte(canonical)); err != nil {
+		return "", err
+	}
+	return base64.StdEncoding.EncodeToString(mac.Sum(nil)), nil
+}
+
+// SignPayload exposes signature calculation for callback verification.
+func SignPayload(payload any, secret string) (string, error) {
+	return signPayload(payload, secret)
+}
+
+func signaturePayloadString(payload any) (string, error) {
+	data, err := json.Marshal(payload)
+	if err != nil {
+		return "", err
+	}
+
+	var root any
+	decoder := json.NewDecoder(bytes.NewReader(data))
+	decoder.UseNumber()
+	if err := decoder.Decode(&root); err != nil {
+		return "", err
+	}
+
+	lines := make([]string, 0)
+	collectSignatureLines(nil, root, &lines)
+	sort.Strings(lines)
+
+	return strings.Join(lines, ";"), nil
+}
+
+func collectSignatureLines(path []string, value any, lines *[]string) {
+	switch v := value.(type) {
+	case map[string]any:
+		for key, child := range v {
+			if strings.EqualFold(key, "signature") {
+				continue
+			}
+			collectSignatureLines(append(path, key), child, lines)
+		}
+	case []any:
+		if len(v) == 0 {
+			return
+		}
+		for idx, child := range v {
+			collectSignatureLines(append(path, strconv.Itoa(idx)), child, lines)
+		}
+	default:
+		line := formatSignatureLine(path, v)
+		if line != "" {
+			*lines = append(*lines, line)
+		}
+	}
+}
+
+func formatSignatureLine(path []string, value any) string {
+	if len(path) == 0 {
+		return ""
+	}
+	val := signatureValueString(value)
+	segments := append(append([]string{}, path...), val)
+	return strings.Join(segments, ":")
+}
+
+func signatureValueString(value any) string {
+	switch v := value.(type) {
+	case nil:
+		return "null"
+	case string:
+		return v
+	case json.Number:
+		return v.String()
+	case bool:
+		if v {
+			return "1"
+		}
+		return "0"
+	case float64:
+		return strconv.FormatFloat(v, 'f', -1, 64)
+	case float32:
+		return strconv.FormatFloat(float64(v), 'f', -1, 32)
+	case int:
+		return strconv.Itoa(v)
+	case int8, int16, int32, int64:
+		return fmt.Sprint(v)
+	case uint, uint8, uint16, uint32, uint64:
+		return fmt.Sprint(v)
+	default:
+		return fmt.Sprint(v)
+	}
+}

api/gateway/mntx/internal/service/monetix/signature_test.go

@@ -0,0 +1,148 @@
+package monetix
+
+import "testing"
+
+func TestSignaturePayloadString_Example(t *testing.T) {
+	payload := map[string]any{
+		"general": map[string]any{
+			"project_id": 3254,
+			"payment_id": "id_38202316",
+			"signature":  "<ignored>",
+		},
+		"customer": map[string]any{
+			"id":         "585741",
+			"email":      "johndoe@example.com",
+			"first_name": "John",
+			"last_name":  "Doe",
+			"address":    "Downing str., 23",
+			"identify": map[string]any{
+				"doc_number": "54122312544",
+			},
+			"ip_address": "198.51.100.47",
+		},
+		"payment": map[string]any{
+			"amount":      10800,
+			"currency":    "USD",
+			"description": "Computer keyboards",
+		},
+		"receipt_data": map[string]any{
+			"positions": []any{
+				map[string]any{
+					"quantity":    "10",
+					"amount":      "108",
+					"description": "Computer keyboard",
+				},
+			},
+		},
+		"return_url": map[string]any{
+			"success": "https://paymentpage.example.com/complete-redirect?id=success",
+			"decline": "https://paymentpage.example.com/complete-redirect?id=decline",
+		},
+	}
+
+	got, err := signaturePayloadString(payload)
+	if err != nil {
+		t.Fatalf("failed to build signature string: %v", err)
+	}
+
+	expected := "customer:address:Downing str., 23;customer:email:johndoe@example.com;customer:first_name:John;customer:id:585741;customer:identify:doc_number:54122312544;customer:ip_address:198.51.100.47;customer:last_name:Doe;general:payment_id:id_38202316;general:project_id:3254;payment:amount:10800;payment:currency:USD;payment:description:Computer keyboards;receipt_data:positions:0:amount:108;receipt_data:positions:0:description:Computer keyboard;receipt_data:positions:0:quantity:10;return_url:decline:https://paymentpage.example.com/complete-redirect?id=decline;return_url:success:https://paymentpage.example.com/complete-redirect?id=success"
+	if got != expected {
+		t.Fatalf("unexpected signature string\nexpected: %s\ngot: %s", expected, got)
+	}
+}
+
+func TestSignPayload_Example(t *testing.T) {
+	payload := map[string]any{
+		"general": map[string]any{
+			"project_id": 3254,
+			"payment_id": "id_38202316",
+			"signature":  "<ignored>",
+		},
+		"customer": map[string]any{
+			"id":         "585741",
+			"email":      "johndoe@example.com",
+			"first_name": "John",
+			"last_name":  "Doe",
+			"address":    "Downing str., 23",
+			"identify": map[string]any{
+				"doc_number": "54122312544",
+			},
+			"ip_address": "198.51.100.47",
+		},
+		"payment": map[string]any{
+			"amount":      10800,
+			"currency":    "USD",
+			"description": "Computer keyboards",
+		},
+		"receipt_data": map[string]any{
+			"positions": []any{
+				map[string]any{
+					"quantity":    "10",
+					"amount":      "108",
+					"description": "Computer keyboard",
+				},
+			},
+		},
+		"return_url": map[string]any{
+			"success": "https://paymentpage.example.com/complete-redirect?id=success",
+			"decline": "https://paymentpage.example.com/complete-redirect?id=decline",
+		},
+	}
+
+	got, err := SignPayload(payload, "secret")
+	if err != nil {
+		t.Fatalf("failed to sign payload: %v", err)
+	}
+	expected := "lagSnuspAn+F6XkmQISqwtBg0PsiTy62fF9x33TM+278mnufIDZyi1yP0BQALuCxyikkIxIMbodBn2F8hMdRwA=="
+	if got != expected {
+		t.Fatalf("unexpected signature\nexpected: %s\ngot: %s", expected, got)
+	}
+}
+
+func TestSignaturePayloadString_BooleansAndArrays(t *testing.T) {
+	payload := map[string]any{
+		"flag":       true,
+		"false_flag": false,
+		"empty":      "",
+		"zero":       0,
+		"nested": map[string]any{
+			"list":  []any{},
+			"items": []any{"alpha", "beta"},
+		},
+	}
+
+	got, err := signaturePayloadString(payload)
+	if err != nil {
+		t.Fatalf("failed to build signature string: %v", err)
+	}
+
+	expected := "empty:;false_flag:0;flag:1;nested:items:0:alpha;nested:items:1:beta;zero:0"
+	if got != expected {
+		t.Fatalf("unexpected signature string\nexpected: %s\ngot: %s", expected, got)
+	}
+}
+
+func TestSignPayload_EthEstimateGasExample(t *testing.T) {
+	payload := map[string]any{
+		"jsonrpc": "2.0",
+		"id":      3,
+		"method":  "eth_estimateGas",
+		"params": []any{
+			map[string]any{
+				"from":     "0xfa89b4d534bdeb2713d4ffd893e79d6535fb58f8",
+				"to":       "0x44162e39eefd9296231e772663a92e72958e182f",
+				"gasPrice": "0x64",
+				"data":     "0xa9059cbb00000000000000000000000044162e39eefd9296231e772663a92e72958e182f00000000000000000000000000000000000000000000000000000000000f4240",
+			},
+		},
+	}
+
+	got, err := SignPayload(payload, "1")
+	if err != nil {
+		t.Fatalf("failed to sign payload: %v", err)
+	}
+	expected := "C4WbSvXKSMyX8yLamQcUe/Nzr6nSt9m3HYn4jHSyA7yi/FaTiqk0r8BlfIzfxSCoDaRgrSd82ihgZW+DxELhdQ=="
+	if got != expected {
+		t.Fatalf("unexpected signature\nexpected: %s\ngot: %s", expected, got)
+	}
+}

api/payments/orchestrator/config.yml

@@ -51,6 +51,12 @@ gateway:
   call_timeout_seconds: 3
   insecure: true
 
+mntx:
+  address: "sendico_mntx_gateway:50075"
+  dial_timeout_seconds: 5
+  call_timeout_seconds: 3
+  insecure: true
+
 oracle:
   address: "sendico_fx_oracle:50051"
   dial_timeout_seconds: 5
@@ -60,7 +66,7 @@ oracle:
 card_gateways:
   monetix:
     funding_address: "TGBDXEg9rxSqGFJDcb889zqTjDwx1bmLRF"
-    fee_wallet_ref: "694c124fd76f9f811ac57134"
+    fee_wallet_ref: "694c124ed76f9f811ac57133"
 
 fee_ledger_accounts:
   monetix: "ledger:fees:monetix"

api/payments/orchestrator/internal/server/internal/serverimp.go

@@ -9,6 +9,7 @@ import (
 
 	oracleclient "github.com/tech/sendico/fx/oracle/client"
 	chainclient "github.com/tech/sendico/gateway/chain/client"
+	mntxclient "github.com/tech/sendico/gateway/mntx/client"
 	ledgerclient "github.com/tech/sendico/ledger/client"
 	"github.com/tech/sendico/payments/orchestrator/internal/service/orchestrator"
 	"github.com/tech/sendico/payments/orchestrator/storage"
@@ -36,6 +37,7 @@ type Imp struct {
 	feesConn      *grpc.ClientConn
 	ledgerClient  ledgerclient.Client
 	gatewayClient chainclient.Client
+	mntxClient    mntxclient.Client
 	oracleClient  oracleclient.Client
 }
 
@@ -44,6 +46,7 @@ type config struct {
 	Fees            clientConfig                      `yaml:"fees"`
 	Ledger          clientConfig                      `yaml:"ledger"`
 	Gateway         clientConfig                      `yaml:"gateway"`
+	Mntx            clientConfig                      `yaml:"mntx"`
 	Oracle          clientConfig                      `yaml:"oracle"`
 	CardGateways    map[string]cardGatewayRouteConfig `yaml:"card_gateways"`
 	FeeAccounts     map[string]string                 `yaml:"fee_ledger_accounts"`
@@ -105,6 +108,9 @@ func (i *Imp) Shutdown() {
 	if i.gatewayClient != nil {
 		_ = i.gatewayClient.Close()
 	}
+	if i.mntxClient != nil {
+		_ = i.mntxClient.Close()
+	}
 	if i.oracleClient != nil {
 		_ = i.oracleClient.Close()
 	}
@@ -139,6 +145,11 @@ func (i *Imp) Start() error {
 		i.gatewayClient = gatewayClient
 	}
 
+	mntxClient := i.initMntxClient(cfg.Mntx)
+	if mntxClient != nil {
+		i.mntxClient = mntxClient
+	}
+
 	oracleClient := i.initOracleClient(cfg.Oracle)
 	if oracleClient != nil {
 		i.oracleClient = oracleClient
@@ -155,6 +166,9 @@ func (i *Imp) Start() error {
 		if gatewayClient != nil {
 			opts = append(opts, orchestrator.WithChainGatewayClient(gatewayClient))
 		}
+		if mntxClient != nil {
+			opts = append(opts, orchestrator.WithMntxGateway(mntxClient))
+		}
 		if oracleClient != nil {
 			opts = append(opts, orchestrator.WithOracleClient(oracleClient))
 		}
@@ -192,11 +206,11 @@ func (i *Imp) initFeesClient(cfg clientConfig) (feesv1.FeeEngineClient, *grpc.Cl
 
 	conn, err := grpc.DialContext(dialCtx, addr, grpc.WithTransportCredentials(creds))
 	if err != nil {
-		i.logger.Warn("failed to connect to fees service", zap.String("address", addr), zap.Error(err))
+		i.logger.Warn("Failed to connect to fees service", zap.String("address", addr), zap.Error(err))
 		return nil, nil
 	}
 
-	i.logger.Info("connected to fees service", zap.String("address", addr))
+	i.logger.Info("Connected to fees service", zap.String("address", addr))
 	return feesv1.NewFeeEngineClient(conn), conn
 }
 
@@ -216,10 +230,10 @@ func (i *Imp) initLedgerClient(cfg clientConfig) ledgerclient.Client {
 		Insecure:    cfg.InsecureTransport,
 	})
 	if err != nil {
-		i.logger.Warn("failed to connect to ledger service", zap.String("address", addr), zap.Error(err))
+		i.logger.Warn("Failed to connect to ledger service", zap.String("address", addr), zap.Error(err))
 		return nil
 	}
-	i.logger.Info("connected to ledger service", zap.String("address", addr))
+	i.logger.Info("Connected to ledger service", zap.String("address", addr))
 	return client
 }
 
@@ -246,6 +260,28 @@ func (i *Imp) initGatewayClient(cfg clientConfig) chainclient.Client {
 	return client
 }
 
+func (i *Imp) initMntxClient(cfg clientConfig) mntxclient.Client {
+	addr := cfg.address()
+	if addr == "" {
+		return nil
+	}
+
+	ctx, cancel := context.WithTimeout(context.Background(), cfg.dialTimeout())
+	defer cancel()
+
+	client, err := mntxclient.New(ctx, mntxclient.Config{
+		Address:     addr,
+		DialTimeout: cfg.dialTimeout(),
+		CallTimeout: cfg.callTimeout(),
+	})
+	if err != nil {
+		i.logger.Warn("Failed to connect to mntx gateway service", zap.String("address", addr), zap.Error(err))
+		return nil
+	}
+	i.logger.Info("Connected to mntx gateway service", zap.String("address", addr))
+	return client
+}
+
 func (i *Imp) initOracleClient(cfg clientConfig) oracleclient.Client {
 	addr := cfg.address()
 	if addr == "" {
@@ -262,10 +298,10 @@ func (i *Imp) initOracleClient(cfg clientConfig) oracleclient.Client {
 		Insecure:    cfg.InsecureTransport,
 	})
 	if err != nil {
-		i.logger.Warn("failed to connect to oracle service", zap.String("address", addr), zap.Error(err))
+		i.logger.Warn("Failed to connect to oracle service", zap.String("address", addr), zap.Error(err))
 		return nil
 	}
-	i.logger.Info("connected to oracle service", zap.String("address", addr))
+	i.logger.Info("Connected to oracle service", zap.String("address", addr))
 	return client
 }
 

api/payments/orchestrator/internal/service/orchestrator/command_factory.go

@@ -13,7 +13,7 @@ import (
 type paymentEngine interface {
 	EnsureRepository(ctx context.Context) error
 	BuildPaymentQuote(ctx context.Context, orgRef string, req *orchestratorv1.QuotePaymentRequest) (*orchestratorv1.PaymentQuote, time.Time, error)
-	ResolvePaymentQuote(ctx context.Context, in quoteResolutionInput) (*orchestratorv1.PaymentQuote, error)
+	ResolvePaymentQuote(ctx context.Context, in quoteResolutionInput) (*orchestratorv1.PaymentQuote, *orchestratorv1.PaymentIntent, error)
 	ExecutePayment(ctx context.Context, store storage.PaymentsStore, payment *model.Payment, quote *orchestratorv1.PaymentQuote) error
 	Repository() storage.Repository
 }
@@ -30,7 +30,7 @@ func (e defaultPaymentEngine) BuildPaymentQuote(ctx context.Context, orgRef stri
 	return e.svc.buildPaymentQuote(ctx, orgRef, req)
 }
 
-func (e defaultPaymentEngine) ResolvePaymentQuote(ctx context.Context, in quoteResolutionInput) (*orchestratorv1.PaymentQuote, error) {
+func (e defaultPaymentEngine) ResolvePaymentQuote(ctx context.Context, in quoteResolutionInput) (*orchestratorv1.PaymentQuote, *orchestratorv1.PaymentIntent, error) {
 	return e.svc.resolvePaymentQuote(ctx, in)
 }
 

api/payments/orchestrator/internal/service/orchestrator/handlers_commands.go

@@ -12,6 +12,7 @@ import (
 	"github.com/tech/sendico/pkg/merrors"
 	"github.com/tech/sendico/pkg/mlogger"
 	"github.com/tech/sendico/pkg/mservice"
+	"github.com/tech/sendico/pkg/mutil/mzap"
 	orchestratorv1 "github.com/tech/sendico/pkg/proto/payments/orchestrator/v1"
 	"go.mongodb.org/mongo-driver/bson/primitive"
 	"go.uber.org/zap"
@@ -61,7 +62,13 @@ func (h *quotePaymentCommand) Execute(ctx context.Context, req *orchestratorv1.Q
 		if err := quotesStore.Create(ctx, record); err != nil {
 			return gsresponse.Auto[orchestratorv1.QuotePaymentResponse](h.logger, mservice.PaymentOrchestrator, err)
 		}
-		h.logger.Info("stored payment quote", zap.String("quote_ref", quoteRef), zap.String("org_ref", orgID.Hex()))
+		h.logger.Info(
+			"Stored payment quote",
+			zap.String("quote_ref", quoteRef),
+			mzap.ObjRef("org_ref", orgID),
+			zap.String("idempotency_key", strings.TrimSpace(req.GetIdempotencyKey())),
+			zap.String("kind", intent.GetKind().String()),
+		)
 	}
 
 	return gsresponse.Success(&orchestratorv1.QuotePaymentResponse{Quote: quote})
@@ -79,7 +86,7 @@ func (h *quotePaymentsCommand) Execute(ctx context.Context, req *orchestratorv1.
 	if req == nil {
 		return gsresponse.InvalidArgument[orchestratorv1.QuotePaymentsResponse](h.logger, mservice.PaymentOrchestrator, merrors.InvalidArgument("nil request"))
 	}
-	orgRef, orgID, err := validateMetaAndOrgRef(req.GetMeta())
+	orgID, orgRef, err := validateMetaAndOrgRef(req.GetMeta())
 	if err != nil {
 		return gsresponse.InvalidArgument[orchestratorv1.QuotePaymentsResponse](h.logger, mservice.PaymentOrchestrator, err)
 	}
@@ -101,7 +108,7 @@ func (h *quotePaymentsCommand) Execute(ctx context.Context, req *orchestratorv1.
 			Intent:         intent,
 			PreviewOnly:    req.GetPreviewOnly(),
 		}
-		quote, expiresAt, err := h.engine.BuildPaymentQuote(ctx, orgRef, quoteReq)
+		quote, expiresAt, err := h.engine.BuildPaymentQuote(ctx, orgID, quoteReq)
 		if err != nil {
 			return gsresponse.Auto[orchestratorv1.QuotePaymentsResponse](h.logger, mservice.PaymentOrchestrator, err)
 		}
@@ -132,11 +139,14 @@ func (h *quotePaymentsCommand) Execute(ctx context.Context, req *orchestratorv1.
 			ExpiresAt: expiresAt,
 		}
 		record.SetID(primitive.NewObjectID())
-		record.SetOrganizationRef(orgID)
+		record.SetOrganizationRef(orgRef)
 		if err := quotesStore.Create(ctx, record); err != nil {
 			return gsresponse.Auto[orchestratorv1.QuotePaymentsResponse](h.logger, mservice.PaymentOrchestrator, err)
 		}
-		h.logger.Info("stored payment quotes", zap.String("quote_ref", quoteRef), zap.String("org_ref", orgID.Hex()))
+		h.logger.Info("Stored payment quotes",
+			zap.String("quote_ref", quoteRef), mzap.ObjRef("org_ref", orgRef),
+			zap.String("idempotency_key", baseKey), zap.Int("quote_count", len(quotes)),
+		)
 	}
 
 	return gsresponse.Success(&orchestratorv1.QuotePaymentsResponse{
@@ -158,7 +168,7 @@ func (h *initiatePaymentsCommand) Execute(ctx context.Context, req *orchestrator
 	if req == nil {
 		return gsresponse.InvalidArgument[orchestratorv1.InitiatePaymentsResponse](h.logger, mservice.PaymentOrchestrator, merrors.InvalidArgument("nil request"))
 	}
-	_, orgID, err := validateMetaAndOrgRef(req.GetMeta())
+	_, orgRef, err := validateMetaAndOrgRef(req.GetMeta())
 	if err != nil {
 		return gsresponse.InvalidArgument[orchestratorv1.InitiatePaymentsResponse](h.logger, mservice.PaymentOrchestrator, err)
 	}
@@ -175,7 +185,7 @@ func (h *initiatePaymentsCommand) Execute(ctx context.Context, req *orchestrator
 	if err != nil {
 		return gsresponse.Unavailable[orchestratorv1.InitiatePaymentsResponse](h.logger, mservice.PaymentOrchestrator, err)
 	}
-	record, err := quotesStore.GetByRef(ctx, orgID, quoteRef)
+	record, err := quotesStore.GetByRef(ctx, orgRef, quoteRef)
 	if err != nil {
 		if errors.Is(err, storage.ErrQuoteNotFound) {
 			return gsresponse.FailedPrecondition[orchestratorv1.InitiatePaymentsResponse](h.logger, mservice.PaymentOrchestrator, "quote_not_found", merrors.InvalidArgument("quote_ref not found or expired"))
@@ -213,14 +223,14 @@ func (h *initiatePaymentsCommand) Execute(ctx context.Context, req *orchestrator
 		quoteProto.QuoteRef = quoteRef
 
 		perKey := perIntentIdempotencyKey(idempotencyKey, i, len(intents))
-		if existing, err := getPaymentByIdempotencyKey(ctx, store, orgID, perKey); err == nil && existing != nil {
+		if existing, err := getPaymentByIdempotencyKey(ctx, store, orgRef, perKey); err == nil && existing != nil {
 			payments = append(payments, toProtoPayment(existing))
 			continue
 		} else if err != nil && !errors.Is(err, storage.ErrPaymentNotFound) {
 			return gsresponse.Auto[orchestratorv1.InitiatePaymentsResponse](h.logger, mservice.PaymentOrchestrator, err)
 		}
 
-		entity := newPayment(orgID, intentProto, perKey, req.GetMetadata(), quoteProto)
+		entity := newPayment(orgRef, intentProto, perKey, req.GetMetadata(), quoteProto)
 		if err = store.Create(ctx, entity); err != nil {
 			if errors.Is(err, storage.ErrDuplicatePayment) {
 				return gsresponse.Auto[orchestratorv1.InitiatePaymentsResponse](h.logger, mservice.PaymentOrchestrator, merrors.DataConflict("payment already exists"))
@@ -235,6 +245,13 @@ func (h *initiatePaymentsCommand) Execute(ctx context.Context, req *orchestrator
 		payments = append(payments, toProtoPayment(entity))
 	}
 
+	h.logger.Info(
+		"Payments initiated",
+		mzap.ObjRef("org_ref", orgRef),
+		zap.String("quote_ref", quoteRef),
+		zap.String("idempotency_key", idempotencyKey),
+		zap.Int("payment_count", len(payments)),
+	)
 	return gsresponse.Success(&orchestratorv1.InitiatePaymentsResponse{Payments: payments})
 }
 
@@ -255,13 +272,31 @@ func (h *initiatePaymentCommand) Execute(ctx context.Context, req *orchestratorv
 		return gsresponse.InvalidArgument[orchestratorv1.InitiatePaymentResponse](h.logger, mservice.PaymentOrchestrator, err)
 	}
 	intent := req.GetIntent()
-	if err := requireNonNilIntent(intent); err != nil {
-		return gsresponse.InvalidArgument[orchestratorv1.InitiatePaymentResponse](h.logger, mservice.PaymentOrchestrator, err)
+	quoteRef := strings.TrimSpace(req.GetQuoteRef())
+	hasIntent := intent != nil
+	hasQuote := quoteRef != ""
+	switch {
+	case !hasIntent && !hasQuote:
+		return gsresponse.InvalidArgument[orchestratorv1.InitiatePaymentResponse](h.logger, mservice.PaymentOrchestrator, merrors.InvalidArgument("intent or quote_ref is required"))
+	case hasIntent && hasQuote:
+		return gsresponse.InvalidArgument[orchestratorv1.InitiatePaymentResponse](h.logger, mservice.PaymentOrchestrator, merrors.InvalidArgument("intent and quote_ref are mutually exclusive"))
+	}
+	if hasIntent {
+		if err := requireNonNilIntent(intent); err != nil {
+			return gsresponse.InvalidArgument[orchestratorv1.InitiatePaymentResponse](h.logger, mservice.PaymentOrchestrator, err)
+		}
 	}
 	idempotencyKey, err := requireIdempotencyKey(req.GetIdempotencyKey())
 	if err != nil {
 		return gsresponse.InvalidArgument[orchestratorv1.InitiatePaymentResponse](h.logger, mservice.PaymentOrchestrator, err)
 	}
+	h.logger.Debug(
+		"Initiate payment request accepted",
+		zap.String("org_ref", orgID.Hex()),
+		zap.String("idempotency_key", idempotencyKey),
+		zap.String("quote_ref", quoteRef),
+		zap.Bool("has_intent", hasIntent),
+	)
 
 	store, err := ensurePaymentsStore(h.engine.Repository())
 	if err != nil {
@@ -269,18 +304,24 @@ func (h *initiatePaymentCommand) Execute(ctx context.Context, req *orchestratorv
 	}
 
 	if existing, err := getPaymentByIdempotencyKey(ctx, store, orgID, idempotencyKey); err == nil && existing != nil {
-		h.logger.Debug("idempotent payment request reused", zap.String("payment_ref", existing.PaymentRef), zap.String("org_ref", orgID.Hex()))
+		h.logger.Debug(
+			"idempotent payment request reused",
+			zap.String("payment_ref", existing.PaymentRef),
+			zap.String("org_ref", orgID.Hex()),
+			zap.String("idempotency_key", idempotencyKey),
+			zap.String("quote_ref", quoteRef),
+		)
 		return gsresponse.Success(&orchestratorv1.InitiatePaymentResponse{Payment: toProtoPayment(existing)})
 	} else if err != nil && !errors.Is(err, storage.ErrPaymentNotFound) {
 		return gsresponse.Auto[orchestratorv1.InitiatePaymentResponse](h.logger, mservice.PaymentOrchestrator, err)
 	}
 
-	quoteSnapshot, err := h.engine.ResolvePaymentQuote(ctx, quoteResolutionInput{
+	quoteSnapshot, resolvedIntent, err := h.engine.ResolvePaymentQuote(ctx, quoteResolutionInput{
 		OrgRef:         orgRef,
 		OrgID:          orgID,
 		Meta:           req.GetMeta(),
 		Intent:         intent,
-		QuoteRef:       req.GetQuoteRef(),
+		QuoteRef:       quoteRef,
 		IdempotencyKey: req.GetIdempotencyKey(),
 	})
 	if err != nil {
@@ -301,8 +342,17 @@ func (h *initiatePaymentCommand) Execute(ctx context.Context, req *orchestratorv
 	if quoteSnapshot == nil {
 		quoteSnapshot = &orchestratorv1.PaymentQuote{}
 	}
+	if err := requireNonNilIntent(resolvedIntent); err != nil {
+		return gsresponse.InvalidArgument[orchestratorv1.InitiatePaymentResponse](h.logger, mservice.PaymentOrchestrator, err)
+	}
+	h.logger.Debug(
+		"Payment quote resolved",
+		zap.String("org_ref", orgID.Hex()),
+		zap.String("quote_ref", quoteRef),
+		zap.Bool("quote_ref_used", quoteRef != ""),
+	)
 
-	entity := newPayment(orgID, intent, idempotencyKey, req.GetMetadata(), quoteSnapshot)
+	entity := newPayment(orgID, resolvedIntent, idempotencyKey, req.GetMetadata(), quoteSnapshot)
 
 	if err = store.Create(ctx, entity); err != nil {
 		if errors.Is(err, storage.ErrDuplicatePayment) {
@@ -315,7 +365,14 @@ func (h *initiatePaymentCommand) Execute(ctx context.Context, req *orchestratorv
 		return gsresponse.Auto[orchestratorv1.InitiatePaymentResponse](h.logger, mservice.PaymentOrchestrator, err)
 	}
 
-	h.logger.Info("payment initiated", zap.String("payment_ref", entity.PaymentRef), zap.String("org_ref", orgID.Hex()), zap.String("kind", intent.GetKind().String()))
+	h.logger.Info(
+		"Payment initiated",
+		zap.String("payment_ref", entity.PaymentRef),
+		zap.String("org_ref", orgID.Hex()),
+		zap.String("kind", resolvedIntent.GetKind().String()),
+		zap.String("quote_ref", quoteSnapshot.GetQuoteRef()),
+		zap.String("idempotency_key", idempotencyKey),
+	)
 	return gsresponse.Success(&orchestratorv1.InitiatePaymentResponse{
 		Payment: toProtoPayment(entity),
 	})
@@ -355,7 +412,7 @@ func (h *cancelPaymentCommand) Execute(ctx context.Context, req *orchestratorv1.
 	if err := store.Update(ctx, payment); err != nil {
 		return gsresponse.Auto[orchestratorv1.CancelPaymentResponse](h.logger, mservice.PaymentOrchestrator, err)
 	}
-	h.logger.Info("payment cancelled", zap.String("payment_ref", payment.PaymentRef), zap.String("org_ref", payment.OrganizationRef.Hex()))
+	h.logger.Info("Payment cancelled", zap.String("payment_ref", payment.PaymentRef), zap.String("org_ref", payment.OrganizationRef.Hex()))
 	return gsresponse.Success(&orchestratorv1.CancelPaymentResponse{Payment: toProtoPayment(payment)})
 }
 
@@ -396,7 +453,7 @@ func (h *initiateConversionCommand) Execute(ctx context.Context, req *orchestrat
 	}
 
 	if existing, err := getPaymentByIdempotencyKey(ctx, store, orgID, idempotencyKey); err == nil && existing != nil {
-		h.logger.Debug("idempotent conversion request reused", zap.String("payment_ref", existing.PaymentRef), zap.String("org_ref", orgID.Hex()))
+		h.logger.Debug("Idempotent conversion request reused", zap.String("payment_ref", existing.PaymentRef), zap.String("org_ref", orgID.Hex()))
 		return gsresponse.Success(&orchestratorv1.InitiateConversionResponse{Conversion: toProtoPayment(existing)})
 	} else if err != nil && !errors.Is(err, storage.ErrPaymentNotFound) {
 		return gsresponse.Auto[orchestratorv1.InitiateConversionResponse](h.logger, mservice.PaymentOrchestrator, err)
@@ -439,7 +496,7 @@ func (h *initiateConversionCommand) Execute(ctx context.Context, req *orchestrat
 		return gsresponse.Auto[orchestratorv1.InitiateConversionResponse](h.logger, mservice.PaymentOrchestrator, err)
 	}
 
-	h.logger.Info("conversion initiated", zap.String("payment_ref", entity.PaymentRef), zap.String("org_ref", orgID.Hex()))
+	h.logger.Info("Conversion initiated", zap.String("payment_ref", entity.PaymentRef), zap.String("org_ref", orgID.Hex()))
 	return gsresponse.Success(&orchestratorv1.InitiateConversionResponse{
 		Conversion: toProtoPayment(entity),
 	})

api/payments/orchestrator/internal/service/orchestrator/service_helpers.go

@@ -103,33 +103,40 @@ type quoteResolutionError struct {
 
 func (e quoteResolutionError) Error() string { return e.err.Error() }
 
-func (s *Service) resolvePaymentQuote(ctx context.Context, in quoteResolutionInput) (*orchestratorv1.PaymentQuote, error) {
+func (s *Service) resolvePaymentQuote(ctx context.Context, in quoteResolutionInput) (*orchestratorv1.PaymentQuote, *orchestratorv1.PaymentIntent, error) {
 	if ref := strings.TrimSpace(in.QuoteRef); ref != "" {
 		quotesStore, err := ensureQuotesStore(s.storage)
 		if err != nil {
-			return nil, err
+			return nil, nil, err
 		}
 		record, err := quotesStore.GetByRef(ctx, in.OrgID, ref)
 		if err != nil {
 			if errors.Is(err, storage.ErrQuoteNotFound) {
-				return nil, quoteResolutionError{code: "quote_not_found", err: merrors.InvalidArgument("quote_ref not found or expired")}
+				return nil, nil, quoteResolutionError{code: "quote_not_found", err: merrors.InvalidArgument("quote_ref not found or expired")}
 			}
-			return nil, err
+			return nil, nil, err
 		}
 		if !record.ExpiresAt.IsZero() && s.clock.Now().After(record.ExpiresAt) {
-			return nil, quoteResolutionError{code: "quote_expired", err: merrors.InvalidArgument("quote_ref expired")}
+			return nil, nil, quoteResolutionError{code: "quote_expired", err: merrors.InvalidArgument("quote_ref expired")}
 		}
-		if !proto.Equal(protoIntentFromModel(record.Intent), in.Intent) {
-			return nil, quoteResolutionError{code: "quote_intent_mismatch", err: merrors.InvalidArgument("quote_ref does not match intent")}
+		intent, err := recordIntentFromQuote(record)
+		if err != nil {
+			return nil, nil, err
 		}
-		quote := modelQuoteToProto(record.Quote)
-		if quote == nil {
-			return nil, merrors.InvalidArgument("stored quote is empty")
+		if in.Intent != nil && !proto.Equal(intent, in.Intent) {
+			return nil, nil, quoteResolutionError{code: "quote_intent_mismatch", err: merrors.InvalidArgument("quote_ref does not match intent")}
+		}
+		quote, err := recordQuoteFromQuote(record)
+		if err != nil {
+			return nil, nil, err
 		}
 		quote.QuoteRef = ref
-		return quote, nil
+		return quote, intent, nil
 	}
 
+	if in.Intent == nil {
+		return nil, nil, merrors.InvalidArgument("intent is required")
+	}
 	req := &orchestratorv1.QuotePaymentRequest{
 		Meta:           in.Meta,
 		IdempotencyKey: in.IdempotencyKey,
@@ -138,9 +145,41 @@ func (s *Service) resolvePaymentQuote(ctx context.Context, in quoteResolutionInp
 	}
 	quote, _, err := s.buildPaymentQuote(ctx, in.OrgRef, req)
 	if err != nil {
-		return nil, err
+		return nil, nil, err
 	}
-	return quote, nil
+	return quote, in.Intent, nil
+}
+
+func recordIntentFromQuote(record *model.PaymentQuoteRecord) (*orchestratorv1.PaymentIntent, error) {
+	if record == nil {
+		return nil, merrors.InvalidArgument("stored quote payload is incomplete")
+	}
+	if len(record.Intents) > 0 {
+		if len(record.Intents) != 1 {
+			return nil, merrors.InvalidArgument("stored quote payload is incomplete")
+		}
+		return protoIntentFromModel(record.Intents[0]), nil
+	}
+	if record.Intent.Amount == nil && (record.Intent.Kind == "" || record.Intent.Kind == model.PaymentKindUnspecified) {
+		return nil, merrors.InvalidArgument("stored quote payload is incomplete")
+	}
+	return protoIntentFromModel(record.Intent), nil
+}
+
+func recordQuoteFromQuote(record *model.PaymentQuoteRecord) (*orchestratorv1.PaymentQuote, error) {
+	if record == nil {
+		return nil, merrors.InvalidArgument("stored quote is empty")
+	}
+	if record.Quote != nil {
+		return modelQuoteToProto(record.Quote), nil
+	}
+	if len(record.Quotes) > 0 {
+		if len(record.Quotes) != 1 {
+			return nil, merrors.InvalidArgument("stored quote payload is incomplete")
+		}
+		return modelQuoteToProto(record.Quotes[0]), nil
+	}
+	return nil, merrors.InvalidArgument("stored quote is empty")
 }
 
 func newPayment(orgID primitive.ObjectID, intent *orchestratorv1.PaymentIntent, idempotencyKey string, metadata map[string]string, quote *orchestratorv1.PaymentQuote) *model.Payment {

api/payments/orchestrator/internal/service/orchestrator/service_helpers_test.go

@@ -73,7 +73,7 @@ func TestResolvePaymentQuote_NotFound(t *testing.T) {
 		storage: stubRepo{quotes: &helperQuotesStore{}},
 		clock:   clockpkg.NewSystem(),
 	}
-	_, err := svc.resolvePaymentQuote(context.Background(), quoteResolutionInput{
+	_, _, err := svc.resolvePaymentQuote(context.Background(), quoteResolutionInput{
 		OrgRef:   org.Hex(),
 		OrgID:    org,
 		Meta:     &orchestratorv1.RequestMeta{OrganizationRef: org.Hex()},
@@ -98,7 +98,7 @@ func TestResolvePaymentQuote_Expired(t *testing.T) {
 		storage: stubRepo{quotes: &helperQuotesStore{records: map[string]*model.PaymentQuoteRecord{"q1": record}}},
 		clock:   clockpkg.NewSystem(),
 	}
-	_, err := svc.resolvePaymentQuote(context.Background(), quoteResolutionInput{
+	_, _, err := svc.resolvePaymentQuote(context.Background(), quoteResolutionInput{
 		OrgRef:   org.Hex(),
 		OrgID:    org,
 		Meta:     &orchestratorv1.RequestMeta{OrganizationRef: org.Hex()},
@@ -110,6 +110,35 @@ func TestResolvePaymentQuote_Expired(t *testing.T) {
 	}
 }
 
+func TestResolvePaymentQuote_QuoteRefUsesStoredIntent(t *testing.T) {
+	org := primitive.NewObjectID()
+	intent := &orchestratorv1.PaymentIntent{Amount: &moneyv1.Money{Currency: "USD", Amount: "1"}}
+	record := &model.PaymentQuoteRecord{
+		QuoteRef: "q1",
+		Intent:   intentFromProto(intent),
+		Quote:    &model.PaymentQuoteSnapshot{},
+	}
+	svc := &Service{
+		storage: stubRepo{quotes: &helperQuotesStore{records: map[string]*model.PaymentQuoteRecord{"q1": record}}},
+		clock:   clockpkg.NewSystem(),
+	}
+	quote, resolvedIntent, err := svc.resolvePaymentQuote(context.Background(), quoteResolutionInput{
+		OrgRef:   org.Hex(),
+		OrgID:    org,
+		Meta:     &orchestratorv1.RequestMeta{OrganizationRef: org.Hex()},
+		QuoteRef: "q1",
+	})
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if quote == nil || quote.GetQuoteRef() != "q1" {
+		t.Fatalf("expected quote_ref q1, got %#v", quote)
+	}
+	if resolvedIntent == nil || resolvedIntent.GetAmount().GetAmount() != "1" {
+		t.Fatalf("expected resolved intent with amount, got %#v", resolvedIntent)
+	}
+}
+
 func TestInitiatePaymentIdempotency(t *testing.T) {
 	logger := mloggerfactory.NewLogger(false)
 	org := primitive.NewObjectID()
@@ -140,6 +169,42 @@ func TestInitiatePaymentIdempotency(t *testing.T) {
 	}
 }
 
+func TestInitiatePaymentByQuoteRef(t *testing.T) {
+	logger := mloggerfactory.NewLogger(false)
+	org := primitive.NewObjectID()
+	store := newHelperPaymentStore()
+	intent := &orchestratorv1.PaymentIntent{Amount: &moneyv1.Money{Currency: "USD", Amount: "1"}}
+	record := &model.PaymentQuoteRecord{
+		QuoteRef: "q1",
+		Intent:   intentFromProto(intent),
+		Quote:    &model.PaymentQuoteSnapshot{},
+	}
+	svc := NewService(logger, stubRepo{
+		payments: store,
+		quotes:   &helperQuotesStore{records: map[string]*model.PaymentQuoteRecord{"q1": record}},
+	}, WithClock(clockpkg.NewSystem()))
+	svc.ensureHandlers()
+
+	req := &orchestratorv1.InitiatePaymentRequest{
+		Meta:           &orchestratorv1.RequestMeta{OrganizationRef: org.Hex()},
+		QuoteRef:       "q1",
+		IdempotencyKey: "k1",
+	}
+	resp, err := svc.h.commands.InitiatePayment().Execute(context.Background(), req)(context.Background())
+	if err != nil {
+		t.Fatalf("initiate by quote_ref failed: %v", err)
+	}
+	if resp == nil || resp.GetPayment() == nil {
+		t.Fatalf("expected payment response")
+	}
+	if resp.GetPayment().GetIntent().GetAmount().GetAmount() != "1" {
+		t.Fatalf("expected intent amount to be resolved from quote")
+	}
+	if resp.GetPayment().GetLastQuote().GetQuoteRef() != "q1" {
+		t.Fatalf("expected last quote_ref to be set from stored quote")
+	}
+}
+
 // --- test doubles ---
 
 type stubRepo struct {

api/server/internal/server/paymentapiimp/pay.go

@@ -8,6 +8,7 @@ import (
 	"github.com/tech/sendico/pkg/api/http/response"
 	"github.com/tech/sendico/pkg/merrors"
 	"github.com/tech/sendico/pkg/model"
+	"github.com/tech/sendico/pkg/mutil/mzap"
 	orchestratorv1 "github.com/tech/sendico/pkg/proto/payments/orchestrator/v1"
 	"github.com/tech/sendico/server/interface/api/srequest"
 	"github.com/tech/sendico/server/interface/api/sresponse"
@@ -20,7 +21,7 @@ import (
 func (a *PaymentAPI) initiatePayment(r *http.Request, account *model.Account, token *sresponse.TokenData, expectQuote bool) http.HandlerFunc {
 	orgRef, err := a.oph.GetRef(r)
 	if err != nil {
-		a.logger.Warn("Failed to parse organization reference for payment initiation", zap.Error(err), zap.String(a.oph.Name(), a.oph.GetID(r)))
+		a.logger.Warn("Failed to parse organization reference for payment initiation", zap.Error(err), mutil.PLog(a.oph, r))
 		return response.BadReference(a.logger, a.Name(), a.oph.Name(), a.oph.GetID(r), err)
 	}
 
@@ -76,7 +77,7 @@ func (a *PaymentAPI) initiatePayment(r *http.Request, account *model.Account, to
 
 	resp, err := a.client.InitiatePayment(ctx, req)
 	if err != nil {
-		a.logger.Warn("Failed to initiate payment", zap.Error(err), zap.String("organization_ref", orgRef.Hex()))
+		a.logger.Warn("Failed to initiate payment", zap.Error(err), mzap.ObjRef("organization_ref", orgRef))
 		return response.Auto(a.logger, a.Name(), err)
 	}
 

frontend/pshared/lib/api/responses/payment/payment.dart

@@ -0,0 +1,20 @@
+import 'package:json_annotation/json_annotation.dart';
+
+import 'package:pshared/api/responses/base.dart';
+import 'package:pshared/api/responses/token.dart';
+import 'package:pshared/data/dto/payment/payment.dart';
+
+part 'payment.g.dart';
+
+
+@JsonSerializable(explicitToJson: true)
+class PaymentResponse extends BaseAuthorizedResponse {
+
+  final PaymentDTO payment;
+
+  const PaymentResponse({required super.accessToken, required this.payment});
+
+  factory PaymentResponse.fromJson(Map<String, dynamic> json) => _$PaymentResponseFromJson(json);
+  @override
+  Map<String, dynamic> toJson() => _$PaymentResponseToJson(this);
+}

frontend/pshared/lib/provider/payment/provider.dart

@@ -0,0 +1,64 @@
+import 'package:flutter/foundation.dart';
+
+import 'package:pshared/models/payment/payment.dart';
+import 'package:pshared/provider/organizations.dart';
+import 'package:pshared/provider/payment/quotation.dart';
+import 'package:pshared/provider/resource.dart';
+import 'package:pshared/service/payment/service.dart';
+
+
+class PaymentProvider extends ChangeNotifier {
+  late OrganizationsProvider _organization;
+  late QuotationProvider _quotation;
+
+  Resource<Payment> _payment = Resource(data: null, isLoading: false, error: null);
+  bool _isLoaded = false;
+
+  void update(OrganizationsProvider organization, QuotationProvider quotation) {
+    _quotation = quotation;
+    _organization = organization;
+  }
+
+  Payment? get payment => _payment.data;
+  bool get isLoading => _payment.isLoading;
+  Exception? get error => _payment.error;
+  bool get isReady => _isLoaded && !_payment.isLoading && _payment.error == null;
+
+  void _setResource(Resource<Payment> payment) {
+    _payment = payment;
+    notifyListeners();
+  }
+
+  Future<Payment?> pay({String? idempotencyKey, Map<String, String>? metadata}) async {
+    if (!_organization.isOrganizationSet) throw StateError('Organization is not set');
+    if (!_quotation.isReady) throw StateError('Quotation is not ready');
+    final quoteRef = _quotation.quotation?.quoteRef;
+    if (quoteRef == null || quoteRef.isEmpty) {
+      throw StateError('Quotation reference is not set');
+    }
+
+    _setResource(_payment.copyWith(isLoading: true, error: null));
+    try {
+      final response = await PaymentService.pay(
+        _organization.current.id,
+        quoteRef,
+        idempotencyKey: idempotencyKey,
+        metadata: metadata,
+      );
+      _isLoaded = true;
+      _setResource(_payment.copyWith(data: response, isLoading: false, error: null));
+    } catch (e) {
+      _setResource(_payment.copyWith(
+        data: null,
+        error: e is Exception ? e : Exception(e.toString()),
+        isLoading: false,
+      ));
+    }
+    return _payment.data;
+  }
+
+  void reset() {
+    _setResource(Resource(data: null, isLoading: false, error: null));
+    _isLoaded = false;
+  }
+}

frontend/pshared/lib/service/payment/service.dart

@@ -0,0 +1,36 @@
+import 'package:logging/logging.dart';
+
+import 'package:uuid/uuid.dart';
+
+import 'package:pshared/api/requests/payment/initiate.dart';
+import 'package:pshared/api/responses/payment/payment.dart';
+import 'package:pshared/data/mapper/payment/payment_response.dart';
+import 'package:pshared/models/payment/payment.dart';
+import 'package:pshared/service/authorization/service.dart';
+import 'package:pshared/service/services.dart';
+
+
+class PaymentService {
+  static final _logger = Logger('service.payment');
+  static const String _objectType = Services.payments;
+
+  static Future<Payment> pay(
+    String organizationRef,
+    String quotationRef, {
+    String? idempotencyKey,
+    Map<String, String>? metadata,
+  }) async {
+    _logger.fine('Executing payment for quotation $quotationRef in $organizationRef');
+    final request = InitiatePaymentRequest(
+      idempotencyKey: idempotencyKey ?? Uuid().v4(),
+      quoteRef: quotationRef,
+      metadata: metadata,
+    );
+    final response = await AuthorizationService.getPOSTResponse(
+      _objectType, 
+      '/by-quote/$organizationRef', 
+      request.toJson(),
+    );
+    return PaymentResponse.fromJson(response).payment.toDomain();
+  }  
+}

frontend/pweb/lib/pages/dashboard/payouts/widget.dart

@@ -1,31 +0,0 @@
-import 'package:flutter/material.dart';
-
-import 'package:provider/provider.dart';
-
-import 'package:pshared/provider/organizations.dart';
-import 'package:pshared/provider/payment/amount.dart';
-import 'package:pshared/provider/payment/flow.dart';
-import 'package:pshared/provider/payment/quotation.dart';
-import 'package:pshared/provider/payment/wallets.dart';
-import 'package:pshared/provider/recipient/pmethods.dart';
-
-import 'package:pweb/pages/dashboard/payouts/form.dart';
-
-
-class PaymentFromWrappingWidget extends StatelessWidget {
-  const PaymentFromWrappingWidget({super.key});
-
-  @override
-  Widget build(BuildContext context) => MultiProvider(
-    providers: [
-      ChangeNotifierProvider(
-        create: (_) => PaymentAmountProvider(),
-      ),
-      ChangeNotifierProxyProvider5<OrganizationsProvider, PaymentAmountProvider, WalletsProvider, PaymentFlowProvider, PaymentMethodsProvider, QuotationProvider>(
-        create: (_) => QuotationProvider(),
-        update: (context, orgnization, payment, wallet, flow, methods, provider) => provider!..update(orgnization, payment, wallet, flow, methods),
-      ),
-    ],
-    child: const PaymentFormWidget(),
-  );
-}

frontend/pweb/lib/pages/payment_methods/page.dart

@@ -8,7 +8,11 @@ import 'package:pshared/models/payment/methods/data.dart';
 import 'package:pshared/models/payment/methods/type.dart';
 import 'package:pshared/models/payment/type.dart';
 import 'package:pshared/models/recipient/recipient.dart';
+import 'package:pshared/provider/organizations.dart';
+import 'package:pshared/provider/payment/amount.dart';
 import 'package:pshared/provider/payment/flow.dart';
+import 'package:pshared/provider/payment/provider.dart';
+import 'package:pshared/provider/payment/quotation.dart';
 import 'package:pshared/provider/recipient/pmethods.dart';
 import 'package:pshared/provider/recipient/provider.dart';
 
@@ -38,16 +42,12 @@ class PaymentPage extends StatefulWidget {
 class _PaymentPageState extends State<PaymentPage> {
   late final TextEditingController _searchController;
   late final FocusNode _searchFocusNode;
-  late final PaymentFlowProvider _flowProvider;
 
   @override
   void initState() {
     super.initState();
     _searchController = TextEditingController();
     _searchFocusNode = FocusNode();
-    _flowProvider = PaymentFlowProvider(
-      initialType: widget.initialPaymentType ?? PaymentType.bankAccount,
-    );
 
     WidgetsBinding.instance.addPostFrameCallback((_) => _initializePaymentPage());
   }
@@ -56,45 +56,30 @@ class _PaymentPageState extends State<PaymentPage> {
   void dispose() {
     _searchController.dispose();
     _searchFocusNode.dispose();
-    _flowProvider.dispose();
     super.dispose();
   }
 
   void _initializePaymentPage() {
     final methodsProvider = context.read<PaymentMethodsProvider>();
     _handleWalletAutoSelection(methodsProvider);
-
-    final recipient = context.read<RecipientsProvider>().currentObject;
-    _syncFlowProvider(
-      recipient: recipient,
-      methodsProvider: methodsProvider,
-      preferredType: widget.initialPaymentType,
-    );
   }
 
   void _handleSearchChanged(String query) {
     context.read<RecipientsProvider>().setQuery(query);
   }
 
-  void _handleRecipientSelected(Recipient recipient) {
+  void _handleRecipientSelected(BuildContext context, Recipient recipient) {
     final recipientProvider = context.read<RecipientsProvider>();
-    final methodsProvider = context.read<PaymentMethodsProvider>();
-
     recipientProvider.setCurrentObject(recipient.id);
-    _flowProvider.reset(
-      recipient: recipient,
-      availableTypes: _availablePaymentTypes(recipient, methodsProvider),
-      preferredType: widget.initialPaymentType,
-    );
     _clearSearchField();
   }
 
-  void _handleRecipientCleared() {
+  void _handleRecipientCleared(BuildContext context) {
     final recipientProvider = context.read<RecipientsProvider>();
     final methodsProvider = context.read<PaymentMethodsProvider>();
 
     recipientProvider.setCurrentObject(null);
-    _flowProvider.reset(
+    context.read<PaymentFlowProvider>().reset(
       recipient: null,
       availableTypes: _availablePaymentTypes(null, methodsProvider),
       preferredType: widget.initialPaymentType,
@@ -108,9 +93,13 @@ class _PaymentPageState extends State<PaymentPage> {
     context.read<RecipientsProvider>().setQuery('');
   }
 
-  void _handleSendPayment() {
-    // TODO: Handle Payment logic
-    PosthogService.paymentInitiated(method: _flowProvider.selectedType);
+  void _handleSendPayment(BuildContext context) {
+    if (context.read<QuotationProvider>().isReady) {
+      context.read<PaymentProvider>().pay();
+      PosthogService.paymentInitiated(
+        method: context.read<PaymentFlowProvider>().selectedType,
+      );
+    }
   }
 
   @override
@@ -120,27 +109,49 @@ class _PaymentPageState extends State<PaymentPage> {
     final recipient = recipientProvider.currentObject;
     final availableTypes = _availablePaymentTypes(recipient, methodsProvider);
 
-    _syncFlowProvider(
-      recipient: recipient,
-      methodsProvider: methodsProvider,
-      preferredType: recipient != null ? widget.initialPaymentType : null,
-    );
-
-    return ChangeNotifierProvider.value(
-      value: _flowProvider,
-      child: PaymentPageBody(
-        onBack: widget.onBack,
-        fallbackDestination: widget.fallbackDestination,
-        recipient: recipient,
-        recipientProvider: recipientProvider,
-        methodsProvider: methodsProvider,
-        availablePaymentTypes: availableTypes,
-        searchController: _searchController,
-        searchFocusNode: _searchFocusNode,
-        onSearchChanged: _handleSearchChanged,
-        onRecipientSelected: _handleRecipientSelected,
-        onRecipientCleared: _handleRecipientCleared,
-        onSend: _handleSendPayment,
+    return MultiProvider(
+      providers: [
+        ChangeNotifierProxyProvider2<RecipientsProvider, PaymentMethodsProvider, PaymentFlowProvider>(
+          create: (_) => PaymentFlowProvider(
+            initialType: widget.initialPaymentType ?? PaymentType.bankAccount,
+          ),
+          update: (_, recipients, methods, flow) {
+            final currentRecipient = recipients.currentObject;
+            flow!.sync(
+              recipient: currentRecipient,
+              availableTypes: _availablePaymentTypes(currentRecipient, methods),
+              preferredType: currentRecipient != null ? widget.initialPaymentType : null,
+            );
+            return flow;
+          },
+        ),
+        ChangeNotifierProvider(
+          create: (_) => PaymentAmountProvider(),
+        ),
+        ChangeNotifierProxyProvider5<OrganizationsProvider, PaymentAmountProvider, WalletsProvider, PaymentFlowProvider, PaymentMethodsProvider, QuotationProvider>(
+          create: (_) => QuotationProvider(),
+          update: (_, organization, payment, wallet, flow, methods, provider) => provider!..update(organization, payment, wallet, flow, methods),
+        ),
+        ChangeNotifierProxyProvider2<OrganizationsProvider, QuotationProvider, PaymentProvider>(
+          create: (_) => PaymentProvider(), 
+          update: (_, organization, quotation, provider) => provider!..update(organization, quotation),
+        ),
+      ],
+      child: Builder(
+        builder: (innerContext) => PaymentPageBody(
+          onBack: widget.onBack,
+          fallbackDestination: widget.fallbackDestination,
+          recipient: recipient,
+          recipientProvider: recipientProvider,
+          methodsProvider: methodsProvider,
+          availablePaymentTypes: availableTypes,
+          searchController: _searchController,
+          searchFocusNode: _searchFocusNode,
+          onSearchChanged: _handleSearchChanged,
+          onRecipientSelected: (selected) => _handleRecipientSelected(innerContext, selected),
+          onRecipientCleared: () => _handleRecipientCleared(innerContext),
+          onSend: () => _handleSendPayment(innerContext),
+        ),
       ),
     );
   }
@@ -155,18 +166,6 @@ class _PaymentPageState extends State<PaymentPage> {
     }
   }
 
-  void _syncFlowProvider({
-    required Recipient? recipient,
-    required PaymentMethodsProvider methodsProvider,
-    PaymentType? preferredType,
-  }) {
-    _flowProvider.sync(
-      recipient: recipient,
-      availableTypes: _availablePaymentTypes(recipient, methodsProvider),
-      preferredType: preferredType,
-    );
-  }
-
   MethodMap _availablePaymentTypes(
     Recipient? recipient,
     PaymentMethodsProvider methodsProvider,

frontend/pweb/lib/pages/payment_methods/payment_page/page.dart

@@ -8,7 +8,7 @@ import 'package:pshared/provider/recipient/pmethods.dart';
 import 'package:pshared/provider/recipient/provider.dart';
 import 'package:pshared/provider/payment/flow.dart';
 
-import 'package:pweb/pages/dashboard/payouts/widget.dart';
+import 'package:pweb/pages/dashboard/payouts/form.dart';
 import 'package:pweb/pages/payment_methods/payment_page/back_button.dart';
 import 'package:pweb/pages/payment_methods/payment_page/header.dart';
 import 'package:pweb/pages/payment_methods/payment_page/method_selector.dart';
@@ -105,7 +105,7 @@ class PaymentPageContent extends StatelessWidget {
                     availableTypes: availablePaymentTypes,
                   ),
                   SizedBox(height: dimensions.paddingLarge),
-                  const PaymentFromWrappingWidget(),
+                  const PaymentFormWidget(),
                   SizedBox(height: dimensions.paddingXXXLarge),
                   SendButton(onPressed: onSend),
                   SizedBox(height: dimensions.paddingLarge),

frontend/pweb/lib/services/amplitude.dart

@@ -1,210 +0,0 @@
-import 'package:amplitude_flutter/amplitude.dart';
-import 'package:amplitude_flutter/configuration.dart';
-import 'package:amplitude_flutter/constants.dart' as amp;
-import 'package:amplitude_flutter/events/base_event.dart';
-import 'package:flutter/widgets.dart';
-import 'package:pshared/models/account/account.dart';
-import 'package:pshared/models/payment/type.dart';
-import 'package:pshared/models/recipient/status.dart';
-import 'package:pshared/models/recipient/type.dart';
-import 'package:pweb/widgets/sidebar/destinations.dart';
-
-
-class AmplitudeService {
-  static late Amplitude _analytics;
-
-  static Amplitude _amp() => _analytics;
-
-  static Future<void> initialize() async {
-    _analytics = Amplitude(Configuration(
-      apiKey: '12345', //TODO define through App Contants
-      serverZone: amp.ServerZone.eu, //TODO define through App Contants
-    ));
-    await _analytics.isBuilt;
-  }
-
-  static Future<void> identify(Account account) async =>
-      _amp().setUserId(account.id);
-
-  
-  static Future<void> login(Account account) async =>
-      _logEvent(
-        'login',
-        userProperties: {
-          // 'email': account.email, TODO Add email into account
-          'locale': account.locale,
-        },
-      );
-
-  static Future<void> logout() async => _logEvent("logout");
-
-  static Future<void> pageOpened(PayoutDestination page, {String? path, String? uiSource}) async {
-    return _logEvent("pageOpened", eventProperties: {
-      "page": page,
-      if (path != null) "path": path,
-      if (uiSource != null) "uiSource": uiSource,
-    });
-  }
-
-  //TODO Add when registration is ready. User properties {user_id, registration_date, has_wallet (true/false), wallet_balance (should concider loggin it as: 0 / <100 / 100–500 / 500+), preferred_method (Wallet/Card/Bank/IBAN), total_transactions, total_amount, last_payout_date, last_login_date , marketing_source}
-  
-  // static Future<void> registrationStarted(String method, String country) async =>
-  //   _logEvent("registrationStarted", eventProperties: {"method": method, "country": country});
-
-  // static Future<void> registrationCompleted(String method, String country) async =>
-  //     _logEvent("registrationCompleted", eventProperties: {"method": method, "country": country});
-
-  static Future<void> pageNotFound(String url) async =>
-      _logEvent("pageNotFound", eventProperties: {"url": url});
-
-  static Future<void> localeChanged(Locale locale) async =>
-      _logEvent("localeChanged", eventProperties: {"locale": locale.toString()});
-
-  static Future<void> localeMatched(String locale, bool haveRequested) async => //DO we need it?
-      _logEvent("localeMatched", eventProperties: {
-        "locale": locale,
-        "have_requested_locale": haveRequested
-      });
-
-  static Future<void> recipientAddStarted() async =>
-      _logEvent("recipientAddStarted");
-
-  static Future<void> recipientAddCompleted(
-    RecipientType type, 
-    RecipientStatus status, 
-    Set<PaymentType> methods,
-  ) async {
-    _logEvent(
-      "recipientAddCompleted", 
-      eventProperties: {
-        "methods": methods.map((m) => m.name).toList(),
-        "type": type.name,
-        "status": status.name,
-      },
-    );
-  }
-
-  static Future<void> _paymentEvent(
-    String evt,
-    double amount,
-    double fee,
-    bool payerCoversFee,
-    PaymentType source,
-    PaymentType recpientPaymentMethod, {
-    String? message,
-    String? errorType,
-    Map<String, dynamic>? extraProps,
-  }) async {
-    final props = {
-      "amount": amount,
-      "fee": fee,
-      "feeCoveredBy": payerCoversFee ? 'payer' : 'recipient',
-      "source": source,
-      "recipient_method": recpientPaymentMethod,
-      if (message != null) "message": message,
-      if (errorType != null) "error_type": errorType,
-      if (extraProps != null) ...extraProps,
-    };
-    return _logEvent(evt, eventProperties: props);
-  }
-
-  static Future<void> paymentPrepared(double amount, double fee,
-          bool payerCoversFee, PaymentType source, PaymentType recpientPaymentMethod) async =>
-      _paymentEvent("paymentPrepared", amount, fee, payerCoversFee, source, recpientPaymentMethod);
-  //TODO Rework paymentStarted (do i need all those properties or is the event enough? Mb properties should be passed at paymentPrepared)
-  static Future<void> paymentStarted(double amount, double fee,
-          bool payerCoversFee, PaymentType source, PaymentType recpientPaymentMethod) async =>
-      _paymentEvent("paymentStarted", amount, fee, payerCoversFee, source, recpientPaymentMethod);
-
-  static Future<void> paymentFailed(double amount, double fee, bool payerCoversFee,
-      PaymentType source, PaymentType recpientPaymentMethod, String errorType, String message) async =>
-      _paymentEvent("paymentFailed", amount, fee, payerCoversFee, source, recpientPaymentMethod,
-          errorType: errorType, message: message);
-
-  static Future<void> paymentError(double amount, double fee, bool payerCoversFee,
-      PaymentType source,PaymentType recpientPaymentMethod, String message) async =>
-      _paymentEvent("paymentError", amount, fee, payerCoversFee, source, recpientPaymentMethod,
-          message: message);
-
-  static Future<void> paymentSuccess({
-    required double amount,
-    required double fee,
-    required bool payerCoversFee,
-    required PaymentType source, 
-    required PaymentType recpientPaymentMethod,
-    required String transactionId,
-    String? comment,
-    required int durationMs,
-  }) async {
-    return _paymentEvent(
-      "paymentSuccess",
-      amount,
-      fee,
-      payerCoversFee,
-      source,
-      recpientPaymentMethod,
-      message: comment,
-      extraProps: {
-        "transaction_id": transactionId,
-        "duration_ms": durationMs, //How do i calculate duration here?
-        "\$revenue": amount, //How do i calculate revenue here?
-        "\$revenueType": "payment", //Do we need to get revenue type?
-      },
-    );
-  }
-
-  //TODO add when support is ready
-  // static Future<void> supportOpened(String fromPage, String trigger) async =>
-  //     _logEvent("supportOpened", eventProperties: {"from_page": fromPage, "trigger": trigger});
-
-  // static Future<void> supportMessageSent(String category, bool resolved) async =>
-  //     _logEvent("supportMessageSent", eventProperties: {"category": category, "resolved": resolved});
-
-
-  static Future<void> walletTopUp(double amount, PaymentType method) async =>
-      _logEvent("walletTopUp", eventProperties: {"amount": amount, "method": method});
-
-
-  //TODO Decide do we need uiElementClicked or pageOpened is enough?
-  static Future<void> uiElementClicked(String elementName, String page, String uiSource) async =>
-      _logEvent("uiElementClicked", eventProperties: {
-        "element_name": elementName,
-        "page": page,
-        "uiSource": uiSource
-      });
-
-  static final Map<String, int> _stepStartTimes = {};
-  //TODO Consider it as part of payment flow or registration flow or adding recipient and rework accordingly
-  static Future<void> stepStarted(String stepName, {String? context}) async {
-    _stepStartTimes[stepName] = DateTime.now().millisecondsSinceEpoch;
-    return _logEvent("stepStarted", eventProperties: {
-      "step_name": stepName,
-      if (context != null) "context": context,
-    });
-  }
-
-  static Future<void> stepCompleted(String stepName, bool success) async {
-    final now = DateTime.now().millisecondsSinceEpoch;
-    final start = _stepStartTimes[stepName] ?? now;
-    final duration = now - start;
-    return _logEvent("stepCompleted", eventProperties: {
-      "step_name": stepName,
-      "duration_ms": duration,
-      "success": success
-    });
-  }
-
-  static Future<void> _logEvent(
-    String eventType, {
-    Map<String, dynamic>? eventProperties,
-    Map<String, dynamic>? userProperties,
-  }) async {
-    final event = BaseEvent(
-      eventType,
-      eventProperties: eventProperties,
-      userProperties: userProperties,
-    );
-    _amp().track(event);
-    print(event.toString()); //TODO delete when everything is ready
-  }
-}