feat: fire openCashLink eagerly on cold start instead of waiting for nav transition (#970)

On cold launch with a cash link deep link, openCashLink was deferred
until the Loading → Scanner nav transition completed and App.kt's
LaunchedEffect re-fired. This added visible latency before the bill
appeared.

Now buildNavGraphForLaunch carries a pendingAction for OpenCashLink
and Login deep links, and MainRoot fires it immediately alongside
the nav transition so the claim starts in parallel with the Scanner
screen appearing.

Signed-off-by: Brandon McAnsh <git@bmcreations.dev>

Author: bmc08gt

apps/flipcash/app/src/main/kotlin/com/flipcash/app/internal/ui/App.kt

@@ -227,6 +227,28 @@ internal fun App(
                                                 resultStateRegistry = resultStateRegistry,
                                                 barManager = barManager,
                                                 deepLink = { deepLink },
+                                                onPendingAction = { action ->
+                                                    deeplinkHandled = true
+                                                    when (action) {
+                                                        is DeeplinkAction.OpenCashLink ->
+                                                            session.openCashLink(action.entropy)
+                                                        is DeeplinkAction.Login ->
+                                                            viewModel.handleLoginEntropy(
+                                                                action.entropy,
+                                                                onSwitchAccount = {
+                                                                    codeNavigator.replaceAll(
+                                                                        AppRoute.OnboardingFlow(
+                                                                            seed = action.entropy,
+                                                                            fromDeeplink = true
+                                                                        )
+                                                                    )
+                                                                },
+                                                                onDismissed = { }
+                                                            )
+                                                        else -> {}
+                                                    }
+                                                    deepLink = null
+                                                },
                                             ),
                                         )
 

apps/flipcash/app/src/main/kotlin/com/flipcash/app/internal/ui/navigation/AppScreenContent.kt

@@ -27,6 +27,7 @@ import com.flipcash.app.cash.CashScreen
 import com.flipcash.app.contact.verification.VerificationFlowScreen
 import com.flipcash.app.currencycreator.CurrencyCreatorFlowScreen
 import com.flipcash.app.core.AppRoute
+import com.flipcash.app.core.navigation.DeeplinkAction
 import com.flipcash.app.currency.RegionSelectionScreen
 import com.flipcash.app.deposit.DepositFlowScreen
 import com.flipcash.app.directsend.SendFlowScreen
@@ -67,10 +68,11 @@ fun appEntryProvider(
     resultStateRegistry: NavResultStateRegistry,
     barManager: BarManager,
     deepLink: () -> DeepLink?,
+    onPendingAction: (DeeplinkAction) -> Unit = {},
 ): (NavKey) -> NavEntry<NavKey> = entryProvider {
 
     // Loading / splash
-    annotatedEntry<AppRoute.Loading> { MainRoot(deepLink) }
+    annotatedEntry<AppRoute.Loading> { MainRoot(deepLink, onPendingAction) }
 
     // Onboarding flow
     annotatedEntry<AppRoute.OnboardingFlow> { key ->

apps/flipcash/app/src/main/kotlin/com/flipcash/app/internal/ui/navigation/MainRoot.kt

@@ -44,7 +44,10 @@ import kotlinx.coroutines.flow.onEach
 import kotlin.time.Duration.Companion.seconds
 
 @Composable
-internal fun MainRoot(deepLink: () -> DeepLink?) {
+internal fun MainRoot(
+    deepLink: () -> DeepLink?,
+    onPendingAction: (DeeplinkAction) -> Unit = {},
+) {
     val navigator = LocalCodeNavigator.current
     val userManager = LocalUserManager.current!!
     var showLoading by remember { mutableStateOf(false) }
@@ -129,6 +132,13 @@ internal fun MainRoot(deepLink: () -> DeepLink?) {
                             navigator.navigateAll(launch.deeplinkRoutes)
                         }
                     }
+
+                    // Fire eagerly so the claim/login starts in parallel
+                    // with the nav transition instead of waiting for
+                    // App.kt's LaunchedEffect to see a non-Loading route.
+                    if (launch.pendingAction != null) {
+                        onPendingAction(launch.pendingAction)
+                    }
                 }
             }.launchIn(this)
     }
@@ -144,6 +154,7 @@ internal fun MainRoot(deepLink: () -> DeepLink?) {
 internal data class LaunchNavGraph(
     val baseRoutes: List<NavKey>,
     val deeplinkRoutes: List<AppRoute> = emptyList(),
+    val pendingAction: DeeplinkAction? = null,
 ) {
     /**
      * Predict the final backstack that [baseRoutes] + [navigateTo(deeplinkRoutes)] will produce.
@@ -192,8 +203,13 @@ internal fun buildNavGraphForLaunch(
                         baseRoutes = listOf(AppRoute.Main.Scanner),
                         deeplinkRoutes = action.routes,
                     )
-                    // OpenCashLink/Login/ExternalWallet are handled by App.kt's
-                    // LaunchedEffect(deepLink, currentRoute) once we leave Loading.
+
+                    is DeeplinkAction.OpenCashLink,
+                    is DeeplinkAction.Login -> LaunchNavGraph(
+                        baseRoutes = listOf(AppRoute.Main.Scanner),
+                        pendingAction = action,
+                    )
+
                     else -> LaunchNavGraph(listOf(AppRoute.Main.Scanner))
                 }
             } else {

apps/flipcash/app/src/test/kotlin/com/flipcash/app/internal/ui/navigation/BuildNavGraphForLaunchTest.kt

@@ -56,25 +56,29 @@ class BuildNavGraphForLaunchTest {
     }
 
     @Test
-    fun `logged in with OpenCashLink defers to App for dispatch`() {
+    fun `logged in with OpenCashLink fires eagerly via pendingAction`() {
+        val action = DeeplinkAction.OpenCashLink("testEntropy")
         val result = build(
             state = AuthState.Ready,
-            action = DeeplinkAction.OpenCashLink("testEntropy"),
+            action = action,
             deepLink = dummyLink,
         )!!
         assertEquals(listOf(AppRoute.Main.Scanner), result.baseRoutes)
-        assertTrue(result.deeplinkRoutes.isEmpty(), "OpenCashLink must not be consumed by MainRoot")
+        assertTrue(result.deeplinkRoutes.isEmpty())
+        assertEquals(action, result.pendingAction)
     }
 
     @Test
-    fun `logged in with Login action defers to App for dispatch`() {
+    fun `logged in with Login action fires eagerly via pendingAction`() {
+        val action = DeeplinkAction.Login("seed")
         val result = build(
             state = AuthState.Ready,
-            action = DeeplinkAction.Login("seed"),
+            action = action,
             deepLink = dummyLink,
         )!!
         assertEquals(listOf(AppRoute.Main.Scanner), result.baseRoutes)
-        assertTrue(result.deeplinkRoutes.isEmpty(), "Login must not be consumed by MainRoot")
+        assertTrue(result.deeplinkRoutes.isEmpty())
+        assertEquals(action, result.pendingAction)
     }
 
     @Test