looprpc: populate static address swap timing and cost fields

loopd/swapclient_server.go

@@ -1966,6 +1966,10 @@ func (s *swapClientServer) ListStaticAddressSwaps(ctx context.Context,
 
 	var clientSwaps []*looprpc.StaticAddressLoopInSwap
 	for _, swp := range swaps {
+		if swp == nil {
+			continue
+		}
+
 		chainParams, err := s.network.ChainParams()
 		if err != nil {
 			return nil, fmt.Errorf("error getting chain params")
@@ -2005,13 +2009,19 @@ func (s *swapClientServer) ListStaticAddressSwaps(ctx context.Context,
 		if swp.SelectedAmount > 0 {
 			swapAmount = swp.SelectedAmount
 		}
+		costServer := staticAddressLoopInSwapServerCost(swp)
+		initiationTime := staticAddressLoopInTimestamp(swp.InitiationTime)
+		lastUpdateTime := staticAddressLoopInTimestamp(swp.LastUpdateTime)
 		swap := &looprpc.StaticAddressLoopInSwap{
 			SwapHash:                     swp.SwapHash[:],
 			DepositOutpoints:             swp.DepositOutpoints,
 			State:                        state,
 			SwapAmountSatoshis:           int64(swapAmount),
 			PaymentRequestAmountSatoshis: payReqAmount,
 			Deposits:                     protoDeposits,
+			InitiationTime:               initiationTime,
+			LastUpdateTime:               lastUpdateTime,
+			CostServer:                   costServer,
 		}
 
 		clientSwaps = append(clientSwaps, swap)
@@ -2022,6 +2032,31 @@ func (s *swapClientServer) ListStaticAddressSwaps(ctx context.Context,
 	}, nil
 }
 
+func staticAddressLoopInTimestamp(t time.Time) int64 {
+	if t.IsZero() {
+		return 0
+	}
+
+	return t.UnixNano()
+}
+
+// staticAddressLoopInSwapServerCost returns the paid server cost using the
+// legacy ListSwaps cost semantics. Static loop-ins currently only persist the
+// accepted quote fee, and that fee is paid once the swap invoice settles.
+// Timeout-path miner fees are not persisted, so cost_onchain and cost_offchain
+// remain zero instead of returning an estimate as an actual cost.
+func staticAddressLoopInSwapServerCost(swp *loopin.StaticAddressLoopIn) int64 {
+	switch swp.GetState() {
+	case loopin.PaymentReceived, loopin.Succeeded,
+		loopin.SucceededTransitioningFailed:
+
+		return int64(swp.QuotedSwapFee)
+
+	default:
+		return 0
+	}
+}
+
 // GetStaticAddressSummary returns a summary of static address-related
 // information. Amongst deposits and withdrawals and their total values, it also
 // includes a list of detailed deposit information filtered by their state.

loopd/swapclient_server_test.go

@@ -20,6 +20,7 @@ import (
 	"github.com/lightninglabs/loop/looprpc"
 	"github.com/lightninglabs/loop/staticaddr/address"
 	"github.com/lightninglabs/loop/staticaddr/deposit"
+	"github.com/lightninglabs/loop/staticaddr/loopin"
 	"github.com/lightninglabs/loop/staticaddr/script"
 	"github.com/lightninglabs/loop/swap"
 	mock_lnd "github.com/lightninglabs/loop/test"
@@ -306,6 +307,72 @@ func TestSetLiquidityParamsRejectsStaticAutoloopWithoutExperimental(
 	require.ErrorContains(t, err, "--experimental")
 }
 
+// TestStaticAddressLoopInTimestamp verifies that zero timestamps are omitted
+// from static loop-in responses instead of passing a zero time to UnixNano.
+func TestStaticAddressLoopInTimestamp(t *testing.T) {
+	require.Zero(t, staticAddressLoopInTimestamp(time.Time{}))
+
+	timestamp := time.Unix(1_234, 567).UTC()
+	require.Equal(
+		t, timestamp.UnixNano(),
+		staticAddressLoopInTimestamp(timestamp),
+	)
+}
+
+// TestStaticAddressLoopInSwapServerCost verifies that static loop-in server
+// costs are only reported once the invoice payment was received. Timeout path
+// costs are not persisted today, so they are intentionally not estimated here.
+func TestStaticAddressLoopInSwapServerCost(t *testing.T) {
+	const quoteFee = btcutil.Amount(1_234)
+
+	tests := []struct {
+		name       string
+		state      fsm.StateType
+		wantServer int64
+	}{
+		{
+			name:  "pending before payment",
+			state: loopin.SignHtlcTx,
+		},
+		{
+			name:       "payment received",
+			state:      loopin.PaymentReceived,
+			wantServer: int64(quoteFee),
+		},
+		{
+			name:       "succeeded",
+			state:      loopin.Succeeded,
+			wantServer: int64(quoteFee),
+		},
+		{
+			name:       "succeeded transition failed",
+			state:      loopin.SucceededTransitioningFailed,
+			wantServer: int64(quoteFee),
+		},
+		{
+			name:  "timeout swept",
+			state: loopin.HtlcTimeoutSwept,
+		},
+		{
+			name:  "failed",
+			state: loopin.Failed,
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			swap := &loopin.StaticAddressLoopIn{
+				QuotedSwapFee: quoteFee,
+			}
+			swap.SetState(test.state)
+
+			costServer := staticAddressLoopInSwapServerCost(swap)
+
+			require.Equal(t, test.wantServer, costServer)
+		})
+	}
+}
+
 // TestRPCAutoloopReasonStaticLoopInNoCandidate verifies that the new planner
 // reason is exposed over rpc.
 func TestRPCAutoloopReasonStaticLoopInNoCandidate(t *testing.T) {

looprpc/client.proto

@@ -2143,6 +2143,31 @@ message StaticAddressLoopInSwap {
     The deposits that were used for this swap.
     */
     repeated Deposit deposits = 6;
+
+    /*
+    Initiation time of the swap.
+    */
+    int64 initiation_time = 7;
+
+    /*
+    Last update time of the swap.
+    */
+    int64 last_update_time = 8;
+
+    /*
+    Swap server cost.
+    */
+    int64 cost_server = 9;
+
+    /*
+    On-chain transaction cost.
+    */
+    int64 cost_onchain = 10;
+
+    /*
+    Off-chain routing fees.
+    */
+    int64 cost_offchain = 11;
 }
 
 enum StaticAddressLoopInSwapState {

looprpc/client.swagger.json

@@ -2807,6 +2807,31 @@
             "$ref": "#/definitions/looprpcDeposit"
           },
           "description": "The deposits that were used for this swap."
+        },
+        "initiation_time": {
+          "type": "string",
+          "format": "int64",
+          "description": "Initiation time of the swap."
+        },
+        "last_update_time": {
+          "type": "string",
+          "format": "int64",
+          "description": "Last update time of the swap."
+        },
+        "cost_server": {
+          "type": "string",
+          "format": "int64",
+          "description": "Swap server cost."
+        },
+        "cost_onchain": {
+          "type": "string",
+          "format": "int64",
+          "description": "On-chain transaction cost."
+        },
+        "cost_offchain": {
+          "type": "string",
+          "format": "int64",
+          "description": "Off-chain routing fees."
         }
       }
     },