fix: show the amount that leaves on spending confirm

Bitkit/Utilities/SpendingConfirmTotal.swift

@@ -0,0 +1,18 @@
+import Foundation
+
+/// Confirm total for the spending transfer screen: the amount of bitcoin that leaves the wallet.
+enum SpendingConfirmTotal {
+    /// When send-all funds the order, the sweep spends `maxSendable + networkFee` (the spendable balance).
+    /// Otherwise the total is the order fee plus the miner fee.
+    static func leavingAmount(
+        orderFeeSat: UInt64,
+        networkFeeSat: UInt64,
+        shouldUseSendAll: Bool,
+        maxSendable: UInt64?
+    ) -> UInt64 {
+        if shouldUseSendAll, let maxSendable {
+            return maxSendable.saturatingAdd(networkFeeSat)
+        }
+        return orderFeeSat.saturatingAdd(networkFeeSat)
+    }
+}

Bitkit/ViewModels/TransferViewModel.swift

@@ -399,7 +399,12 @@ class TransferViewModel: ObservableObject {
             isMaxAmount: isMaxAmount
         )
 
-        let txTotalSats = order.feeSat + txFee
+        let txTotalSats = SpendingConfirmTotal.leavingAmount(
+            orderFeeSat: order.feeSat,
+            networkFeeSat: txFee,
+            shouldUseSendAll: isMaxAmount,
+            maxSendable: maxSendableAmount
+        )
 
         // Pre-activity metadata lets the LDK activity sync recognize this send as a transfer.
         let currentTime = UInt64(Date().timeIntervalSince1970)

Bitkit/Views/Transfer/SpendingConfirm.swift

@@ -26,7 +26,12 @@ struct SpendingConfirm: View {
     }
 
     var total: UInt64 {
-        transfer.uiState.feeSat + transactionFee
+        SpendingConfirmTotal.leavingAmount(
+            orderFeeSat: transfer.uiState.feeSat,
+            networkFeeSat: transactionFee,
+            shouldUseSendAll: shouldUseSendAll,
+            maxSendable: maxSendableAmount
+        )
     }
 
     var body: some View {

BitkitTests/SpendingConfirmTotalTests.swift

@@ -0,0 +1,77 @@
+@testable import Bitkit
+import XCTest
+
+final class SpendingConfirmTotalTests: XCTestCase {
+    func testNormalPath_UsesOrderFeePlusNetworkFee() {
+        XCTAssertEqual(
+            SpendingConfirmTotal.leavingAmount(
+                orderFeeSat: 50_000,
+                networkFeeSat: 250,
+                shouldUseSendAll: false,
+                maxSendable: nil
+            ),
+            50_250
+        )
+    }
+
+    func testNormalPath_IgnoresStaleMaxSendable() {
+        XCTAssertEqual(
+            SpendingConfirmTotal.leavingAmount(
+                orderFeeSat: 50_000,
+                networkFeeSat: 250,
+                shouldUseSendAll: false,
+                maxSendable: 99_750
+            ),
+            50_250
+        )
+    }
+
+    func testSendAllPath_UsesMaxSendablePlusNetworkFee() {
+        // balance 100_000, send-all fee 250 → maxSendable 99_750; amount leaving = 100_000
+        XCTAssertEqual(
+            SpendingConfirmTotal.leavingAmount(
+                orderFeeSat: 50_000,
+                networkFeeSat: 250,
+                shouldUseSendAll: true,
+                maxSendable: 99_750
+            ),
+            100_000
+        )
+    }
+
+    func testNormalPath_SaturatesOnOverflow() {
+        XCTAssertEqual(
+            SpendingConfirmTotal.leavingAmount(
+                orderFeeSat: UInt64.max,
+                networkFeeSat: 1,
+                shouldUseSendAll: false,
+                maxSendable: nil
+            ),
+            UInt64.max
+        )
+    }
+
+    func testSendAllPath_SaturatesOnOverflow() {
+        XCTAssertEqual(
+            SpendingConfirmTotal.leavingAmount(
+                orderFeeSat: 1,
+                networkFeeSat: 1,
+                shouldUseSendAll: true,
+                maxSendable: UInt64.max
+            ),
+            UInt64.max
+        )
+    }
+
+    func testSendAllPath_WithoutMaxSendable_FallsBackToOrderPlusFee() {
+        XCTAssertEqual(
+            SpendingConfirmTotal.leavingAmount(
+                orderFeeSat: 50_000,
+                networkFeeSat: 250,
+                shouldUseSendAll: true,
+                maxSendable: nil
+            ),
+            50_250
+        )
+    }
+}

changelog.d/next/772.fixed.md

@@ -0,0 +1 @@
+Spending confirm now shows the amount of bitcoin that leaves the wallet when a transfer uses send-all funding, and the transfer record uses that same amount.