Sign in with element classic final

appnav/src/main/kotlin/io/element/android/appnav/RootFlowNode.kt

@@ -252,7 +252,8 @@ class RootFlowNode(
             val transitionHandler = rememberDelegateTransitionHandler<NavTarget, BackStack.State> { navTarget ->
                 when (navTarget) {
                     is NavTarget.SplashScreen,
-                    is NavTarget.LoggedInFlow -> backstackFader
+                    is NavTarget.LoggedInFlow,
+                    is NavTarget.NotLoggedInFlow -> backstackFader
                     else -> backstackSlider
                 }
             }

features/login/impl/src/main/kotlin/io/element/android/features/login/impl/LoginFlowNode.kt

@@ -22,6 +22,7 @@ import com.bumble.appyx.core.plugin.Plugin
 import com.bumble.appyx.navmodel.backstack.BackStack
 import com.bumble.appyx.navmodel.backstack.operation.pop
 import com.bumble.appyx.navmodel.backstack.operation.push
+import com.bumble.appyx.navmodel.backstack.operation.replace
 import com.bumble.appyx.navmodel.backstack.operation.singleTop
 import dev.zacsweers.metro.AppScope
 import dev.zacsweers.metro.Assisted
@@ -30,9 +31,11 @@ import io.element.android.annotations.ContributesNode
 import io.element.android.compound.theme.ElementTheme
 import io.element.android.features.login.api.LoginEntryPoint
 import io.element.android.features.login.impl.accountprovider.AccountProviderDataSource
+import io.element.android.features.login.impl.classic.ElementClassicConnection
 import io.element.android.features.login.impl.qrcode.QrCodeLoginFlowNode
 import io.element.android.features.login.impl.screens.changeaccountprovider.ChangeAccountProviderNode
 import io.element.android.features.login.impl.screens.chooseaccountprovider.ChooseAccountProviderNode
+import io.element.android.features.login.impl.screens.classic.ClassicFlowNode
 import io.element.android.features.login.impl.screens.confirmaccountprovider.ConfirmAccountProviderNode
 import io.element.android.features.login.impl.screens.createaccount.CreateAccountNode
 import io.element.android.features.login.impl.screens.loginpassword.LoginPasswordNode
@@ -63,9 +66,10 @@ class LoginFlowNode(
     private val oidcActionFlow: OidcActionFlow,
     @AppCoroutineScope
     private val appCoroutineScope: CoroutineScope,
+    private val elementClassicConnection: ElementClassicConnection,
 ) : BaseFlowNode<LoginFlowNode.NavTarget>(
     backstack = BackStack(
-        initialElement = NavTarget.OnBoarding,
+        initialElement = NavTarget.CheckClassicFlow,
         savedStateMap = buildContext.savedStateMap,
     ),
     buildContext = buildContext,
@@ -103,7 +107,12 @@ class LoginFlowNode(
 
     sealed interface NavTarget : Parcelable {
         @Parcelize
-        data object OnBoarding : NavTarget
+        data object CheckClassicFlow : NavTarget
+
+        @Parcelize
+        data class OnBoarding(
+            val showBackButton: Boolean,
+        ) : NavTarget
 
         @Parcelize
         data object QrCode : NavTarget
@@ -123,15 +132,41 @@ class LoginFlowNode(
         data object SearchAccountProvider : NavTarget
 
         @Parcelize
-        data object LoginPassword : NavTarget
+        data class LoginPassword(
+            val initialLogin: String = "",
+        ) : NavTarget
 
         @Parcelize
         data class CreateAccount(val url: String) : NavTarget
     }
 
     override fun resolve(navTarget: NavTarget, buildContext: BuildContext): Node {
         return when (navTarget) {
-            NavTarget.OnBoarding -> {
+            NavTarget.CheckClassicFlow -> {
+                val callback = object : ClassicFlowNode.Callback {
+                    override fun navigateToOnBoarding(allowBackNavigation: Boolean) {
+                        if (allowBackNavigation) {
+                            backstack.push(NavTarget.OnBoarding(showBackButton = true))
+                        } else {
+                            backstack.replace(NavTarget.OnBoarding(showBackButton = false))
+                        }
+                    }
+
+                    override fun navigateToLoginPassword() {
+                        backstack.push(NavTarget.LoginPassword())
+                    }
+
+                    override fun navigateToOidc(oidcDetails: OidcDetails) {
+                        navigateToMas(oidcDetails)
+                    }
+
+                    override fun navigateToCreateAccount(url: String) {
+                        backstack.push(NavTarget.CreateAccount(url))
+                    }
+                }
+                createNode<ClassicFlowNode>(buildContext, listOf(callback))
+            }
+            is NavTarget.OnBoarding -> {
                 val callback = object : OnBoardingNode.Callback {
                     override fun navigateToSignUpFlow() {
                         backstack.push(
@@ -166,17 +201,22 @@ class LoginFlowNode(
                     }
 
                     override fun navigateToLoginPassword() {
-                        backstack.push(NavTarget.LoginPassword)
+                        backstack.push(NavTarget.LoginPassword())
                     }
 
                     override fun onDone() {
-                        callback.onDone()
+                        if (navTarget.showBackButton) {
+                            backstack.pop()
+                        } else {
+                            callback.onDone()
+                        }
                     }
                 }
                 val params = inputs<Params>()
                 val inputs = OnBoardingNode.Params(
                     accountProvider = params.accountProvider,
                     loginHint = params.loginHint,
+                    showBackButton = navTarget.showBackButton,
                 )
                 createNode<OnBoardingNode>(buildContext, listOf(callback, inputs))
             }
@@ -191,7 +231,7 @@ class LoginFlowNode(
                     }
 
                     override fun navigateToLoginPassword() {
-                        backstack.push(NavTarget.LoginPassword)
+                        backstack.push(NavTarget.LoginPassword())
                     }
                 }
                 createNode<ChooseAccountProviderNode>(buildContext, listOf(callback))
@@ -218,7 +258,7 @@ class LoginFlowNode(
                     }
 
                     override fun navigateToLoginPassword() {
-                        backstack.push(NavTarget.LoginPassword)
+                        backstack.push(NavTarget.LoginPassword())
                     }
 
                     override fun navigateToChangeAccountProvider() {
@@ -257,8 +297,11 @@ class LoginFlowNode(
 
                 createNode<SearchAccountProviderNode>(buildContext, plugins = listOf(callback))
             }
-            NavTarget.LoginPassword -> {
-                createNode<LoginPasswordNode>(buildContext)
+            is NavTarget.LoginPassword -> {
+                val inputs = LoginPasswordNode.Inputs(
+                    initialLogin = navTarget.initialLogin,
+                )
+                createNode<LoginPasswordNode>(buildContext, plugins = listOf(inputs))
             }
             is NavTarget.CreateAccount -> {
                 val inputs = CreateAccountNode.Inputs(
@@ -280,6 +323,14 @@ class LoginFlowNode(
     override fun View(modifier: Modifier) {
         activity = requireNotNull(LocalActivity.current)
         darkTheme = !ElementTheme.isLightTheme
+
+        DisposableEffect(Unit) {
+            elementClassicConnection.start()
+            onDispose {
+                elementClassicConnection.stop()
+            }
+        }
+
         DisposableEffect(Unit) {
             onDispose {
                 activity = null
@@ -288,6 +339,6 @@ class LoginFlowNode(
                 }
             }
         }
-        BackstackView()
+        BackstackView(transitionHandler = rememberLoginFlowTransitionHandler())
     }
 }

features/login/impl/src/main/kotlin/io/element/android/features/login/impl/LoginFlowTransitionHandler.kt

@@ -0,0 +1,54 @@
+/*
+ * Copyright (c) 2026 Element Creations Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial.
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.features.login.impl
+
+import androidx.compose.animation.core.Spring
+import androidx.compose.animation.core.Transition
+import androidx.compose.animation.core.spring
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import com.bumble.appyx.core.navigation.transition.ModifierTransitionHandler
+import com.bumble.appyx.core.navigation.transition.TransitionDescriptor
+import com.bumble.appyx.navmodel.backstack.BackStack
+import com.bumble.appyx.navmodel.backstack.operation.Replace
+import com.bumble.appyx.navmodel.backstack.transitionhandler.rememberBackstackFader
+import com.bumble.appyx.navmodel.backstack.transitionhandler.rememberBackstackSlider
+import io.element.android.libraries.architecture.appyx.rememberDelegateTransitionHandler
+
+/**
+ * A TransitionHandler that uses fade transition when OnBoarding is replacing the current screen,
+ * and slide transition for all other cases.
+ */
+private class LoginFlowTransitionHandler(
+    private val slider: ModifierTransitionHandler<LoginFlowNode.NavTarget, BackStack.State>,
+    private val fader: ModifierTransitionHandler<LoginFlowNode.NavTarget, BackStack.State>,
+) : ModifierTransitionHandler<LoginFlowNode.NavTarget, BackStack.State>() {
+    override fun createModifier(
+        modifier: Modifier,
+        transition: Transition<BackStack.State>,
+        descriptor: TransitionDescriptor<LoginFlowNode.NavTarget, BackStack.State>
+    ): Modifier {
+        val useFader = descriptor.element is LoginFlowNode.NavTarget.OnBoarding &&
+            descriptor.operation is Replace
+        val handler = if (useFader) fader else slider
+        return handler.createModifier(modifier, transition, descriptor)
+    }
+}
+
+@Composable
+fun rememberLoginFlowTransitionHandler(): ModifierTransitionHandler<LoginFlowNode.NavTarget, BackStack.State> {
+    val slider = rememberBackstackSlider<LoginFlowNode.NavTarget>(
+        transitionSpec = { spring(stiffness = Spring.StiffnessMediumLow) },
+    )
+    val fader = rememberBackstackFader<LoginFlowNode.NavTarget>(
+        transitionSpec = { spring(stiffness = Spring.StiffnessMediumLow) },
+    )
+    return rememberDelegateTransitionHandler {
+        LoginFlowTransitionHandler(slider, fader)
+    }
+}