Account Creation using a WebView

features/login/impl/build.gradle.kts

@@ -44,6 +44,7 @@ dependencies {
     implementation(projects.libraries.oidc.api)
     implementation(libs.androidx.browser)
     implementation(platform(libs.network.retrofit.bom))
+    implementation(libs.androidx.webkit)
     implementation(libs.network.retrofit)
     implementation(libs.serialization.json)
     api(projects.features.login.api)

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

@@ -30,6 +30,7 @@ import io.element.android.features.login.impl.accountprovider.AccountProviderDat
 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.confirmaccountprovider.ConfirmAccountProviderNode
+import io.element.android.features.login.impl.screens.createaccount.CreateAccountNode
 import io.element.android.features.login.impl.screens.loginpassword.LoginPasswordNode
 import io.element.android.features.login.impl.screens.searchaccountprovider.SearchAccountProviderNode
 import io.element.android.libraries.architecture.BackstackView
@@ -109,6 +110,9 @@ class LoginFlowNode @AssistedInject constructor(
         @Parcelize
         data object LoginPassword : NavTarget
 
+        @Parcelize
+        data class CreateAccount(val url: String) : NavTarget
+
         @Parcelize
         data class OidcView(val oidcDetails: OidcDetails) : NavTarget
     }
@@ -140,6 +144,10 @@ class LoginFlowNode @AssistedInject constructor(
                         }
                     }
 
+                    override fun onCreateAccountContinue(url: String) {
+                        backstack.push(NavTarget.CreateAccount(url))
+                    }
+
                     override fun onLoginPasswordNeeded() {
                         backstack.push(NavTarget.LoginPassword)
                     }
@@ -180,6 +188,12 @@ class LoginFlowNode @AssistedInject constructor(
             is NavTarget.OidcView -> {
                 oidcEntryPoint.createFallbackWebViewNode(this, buildContext, navTarget.oidcDetails.url)
             }
+            is NavTarget.CreateAccount -> {
+                val inputs = CreateAccountNode.Inputs(
+                    url = navTarget.url,
+                )
+                createNode<CreateAccountNode>(buildContext, listOf(inputs))
+            }
         }
     }
 

features/login/impl/src/main/kotlin/io/element/android/features/login/impl/resolver/network/ElementWellKnown.kt

@@ -0,0 +1,26 @@
+/*
+ * Copyright 2023, 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Please see LICENSE in the repository root for full details.
+ */
+
+package io.element.android.features.login.impl.resolver.network
+
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+
+/**
+ * Example:
+ * <pre>
+ * {
+ *     "registration_helper_url": "https://element.io"
+ * }
+ * </pre>
+ * .
+ */
+@Serializable
+data class ElementWellKnown(
+    @SerialName("registration_helper_url")
+    val registrationHelperUrl: String? = null,
+)

features/login/impl/src/main/kotlin/io/element/android/features/login/impl/resolver/network/WellknownAPI.kt

@@ -12,4 +12,7 @@ import retrofit2.http.GET
 internal interface WellknownAPI {
     @GET(".well-known/matrix/client")
     suspend fun getWellKnown(): WellKnown
+
+    @GET(".well-known/element/element.json")
+    suspend fun getElementWellKnown(): ElementWellKnown
 }

features/login/impl/src/main/kotlin/io/element/android/features/login/impl/screens/confirmaccountprovider/ConfirmAccountProviderNode.kt

@@ -43,6 +43,7 @@ class ConfirmAccountProviderNode @AssistedInject constructor(
     interface Callback : Plugin {
         fun onLoginPasswordNeeded()
         fun onOidcDetails(oidcDetails: OidcDetails)
+        fun onCreateAccountContinue(url: String)
         fun onChangeAccountProvider()
     }
 
@@ -54,6 +55,10 @@ class ConfirmAccountProviderNode @AssistedInject constructor(
         plugins<Callback>().forEach { it.onLoginPasswordNeeded() }
     }
 
+    private fun onCreateAccountContinue(url: String) {
+        plugins<Callback>().forEach { it.onCreateAccountContinue(url) }
+    }
+
     private fun onChangeAccountProvider() {
         plugins<Callback>().forEach { it.onChangeAccountProvider() }
     }
@@ -67,6 +72,7 @@ class ConfirmAccountProviderNode @AssistedInject constructor(
             modifier = modifier,
             onOidcDetails = ::onOidcDetails,
             onNeedLoginPassword = ::onLoginPasswordNeeded,
+            onCreateAccountContinue = ::onCreateAccountContinue,
             onChange = ::onChangeAccountProvider,
             onLearnMoreClick = { openLearnMorePage(context) },
         )

features/login/impl/src/main/kotlin/io/element/android/features/login/impl/screens/confirmaccountprovider/ConfirmAccountProviderPresenter.kt

@@ -21,6 +21,8 @@ import dagger.assisted.AssistedInject
 import io.element.android.features.login.impl.DefaultLoginUserStory
 import io.element.android.features.login.impl.accountprovider.AccountProviderDataSource
 import io.element.android.features.login.impl.error.ChangeServerError
+import io.element.android.features.login.impl.screens.createaccount.AccountCreationNotSupported
+import io.element.android.features.login.impl.web.WebClientUrlForAuthenticationRetriever
 import io.element.android.libraries.architecture.AsyncData
 import io.element.android.libraries.architecture.Presenter
 import io.element.android.libraries.architecture.runCatchingUpdatingState
@@ -36,6 +38,7 @@ class ConfirmAccountProviderPresenter @AssistedInject constructor(
     private val authenticationService: MatrixAuthenticationService,
     private val oidcActionFlow: OidcActionFlow,
     private val defaultLoginUserStory: DefaultLoginUserStory,
+    private val webClientUrlForAuthenticationRetriever: WebClientUrlForAuthenticationRetriever,
 ) : Presenter<ConfirmAccountProviderState> {
     data class Params(
         val isAccountCreation: Boolean,
@@ -90,13 +93,24 @@ class ConfirmAccountProviderPresenter @AssistedInject constructor(
                 if (matrixHomeServerDetails.supportsOidcLogin) {
                     // Retrieve the details right now
                     LoginFlow.OidcFlow(authenticationService.getOidcUrl().getOrThrow())
+                } else if (params.isAccountCreation) {
+                    val url = webClientUrlForAuthenticationRetriever.retrieve(homeserverUrl)
+                    LoginFlow.AccountCreationFlow(url)
                 } else if (matrixHomeServerDetails.supportsPasswordLogin) {
                     LoginFlow.PasswordLogin
                 } else {
                     error("Unsupported login flow")
                 }
             }.getOrThrow()
-        }.runCatchingUpdatingState(loginFlowAction, errorTransform = ChangeServerError::from)
+        }.runCatchingUpdatingState(
+            state = loginFlowAction,
+            errorTransform = {
+                when (it) {
+                    is AccountCreationNotSupported -> it
+                    else -> ChangeServerError.from(it)
+                }
+            }
+        )
     }
 
     private suspend fun onOidcAction(

features/login/impl/src/main/kotlin/io/element/android/features/login/impl/screens/confirmaccountprovider/ConfirmAccountProviderState.kt

@@ -24,4 +24,5 @@ data class ConfirmAccountProviderState(
 sealed interface LoginFlow {
     data object PasswordLogin : LoginFlow
     data class OidcFlow(val oidcDetails: OidcDetails) : LoginFlow
+    data class AccountCreationFlow(val url: String) : LoginFlow
 }

features/login/impl/src/main/kotlin/io/element/android/features/login/impl/screens/confirmaccountprovider/ConfirmAccountProviderStateProvider.kt

@@ -8,20 +8,33 @@
 package io.element.android.features.login.impl.screens.confirmaccountprovider
 
 import androidx.compose.ui.tooling.preview.PreviewParameterProvider
+import io.element.android.features.login.impl.accountprovider.AccountProvider
 import io.element.android.features.login.impl.accountprovider.anAccountProvider
+import io.element.android.features.login.impl.screens.createaccount.AccountCreationNotSupported
 import io.element.android.libraries.architecture.AsyncData
 
 open class ConfirmAccountProviderStateProvider : PreviewParameterProvider<ConfirmAccountProviderState> {
     override val values: Sequence<ConfirmAccountProviderState>
         get() = sequenceOf(
             aConfirmAccountProviderState(),
-            // Add other state here
+            aConfirmAccountProviderState(
+                isAccountCreation = true,
+            ),
+            aConfirmAccountProviderState(
+                isAccountCreation = true,
+                loginFlow = AsyncData.Failure(AccountCreationNotSupported())
+            ),
         )
 }
 
-fun aConfirmAccountProviderState() = ConfirmAccountProviderState(
+private fun aConfirmAccountProviderState(
-    accountProvider = anAccountProvider(),
+    accountProvider: AccountProvider = anAccountProvider(),
-    isAccountCreation = false,
+    isAccountCreation: Boolean = false,
-    loginFlow = AsyncData.Uninitialized,
+    loginFlow: AsyncData<LoginFlow> = AsyncData.Uninitialized,
-    eventSink = {}
+    eventSink: (ConfirmAccountProviderEvents) -> Unit = {},
+) = ConfirmAccountProviderState(
+    accountProvider = accountProvider,
+    isAccountCreation = isAccountCreation,
+    loginFlow = loginFlow,
+    eventSink = eventSink
 )

features/login/impl/src/main/kotlin/io/element/android/features/login/impl/screens/confirmaccountprovider/ConfirmAccountProviderView.kt

@@ -22,6 +22,7 @@ import androidx.compose.ui.unit.dp
 import io.element.android.features.login.impl.R
 import io.element.android.features.login.impl.dialogs.SlidingSyncNotSupportedDialog
 import io.element.android.features.login.impl.error.ChangeServerError
+import io.element.android.features.login.impl.screens.createaccount.AccountCreationNotSupported
 import io.element.android.libraries.architecture.AsyncData
 import io.element.android.libraries.designsystem.atomic.molecules.ButtonColumnMolecule
 import io.element.android.libraries.designsystem.atomic.molecules.IconTitleSubtitleMolecule
@@ -42,6 +43,7 @@ fun ConfirmAccountProviderView(
     onOidcDetails: (OidcDetails) -> Unit,
     onNeedLoginPassword: () -> Unit,
     onLearnMoreClick: () -> Unit,
+    onCreateAccountContinue: (url: String) -> Unit,
     onChange: () -> Unit,
     modifier: Modifier = Modifier,
 ) {
@@ -116,6 +118,14 @@ fun ConfirmAccountProviderView(
                             eventSink(ConfirmAccountProviderEvents.ClearError)
                         })
                     }
+                    is AccountCreationNotSupported -> {
+                        ErrorDialog(
+                            content = stringResource(CommonStrings.error_account_creation_not_possible),
+                            onDismiss = {
+                                eventSink.invoke(ConfirmAccountProviderEvents.ClearError)
+                            }
+                        )
+                    }
                 }
             }
             is AsyncData.Loading -> Unit // The Continue button shows the loading state
@@ -123,6 +133,7 @@ fun ConfirmAccountProviderView(
                 when (val loginFlowState = state.loginFlow.data) {
                     is LoginFlow.OidcFlow -> onOidcDetails(loginFlowState.oidcDetails)
                     LoginFlow.PasswordLogin -> onNeedLoginPassword()
+                    is LoginFlow.AccountCreationFlow -> onCreateAccountContinue(loginFlowState.url)
                 }
             }
             AsyncData.Uninitialized -> Unit
@@ -139,6 +150,7 @@ internal fun ConfirmAccountProviderViewPreview(
         state = state,
         onOidcDetails = {},
         onNeedLoginPassword = {},
+        onCreateAccountContinue = {},
         onLearnMoreClick = {},
         onChange = {},
     )

features/login/impl/src/main/kotlin/io/element/android/features/login/impl/screens/createaccount/AccountCreationNotSupported.kt

@@ -0,0 +1,10 @@
+/*
+ * Copyright 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Please see LICENSE in the repository root for full details.
+ */
+
+package io.element.android.features.login.impl.screens.createaccount
+
+class AccountCreationNotSupported : Exception()

features/login/impl/src/main/kotlin/io/element/android/features/login/impl/screens/createaccount/CreateAccountEvents.kt

@@ -0,0 +1,13 @@
+/*
+ * Copyright 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Please see LICENSE in the repository root for full details.
+ */
+
+package io.element.android.features.login.impl.screens.createaccount
+
+sealed interface CreateAccountEvents {
+    data class SetPageProgress(val progress: Int) : CreateAccountEvents
+    data class OnMessageReceived(val message: String) : CreateAccountEvents
+}

features/login/impl/src/main/kotlin/io/element/android/features/login/impl/screens/createaccount/CreateAccountNode.kt

@@ -0,0 +1,43 @@
+/*
+ * Copyright 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Please see LICENSE in the repository root for full details.
+ */
+
+package io.element.android.features.login.impl.screens.createaccount
+
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import com.bumble.appyx.core.modality.BuildContext
+import com.bumble.appyx.core.node.Node
+import com.bumble.appyx.core.plugin.Plugin
+import dagger.assisted.Assisted
+import dagger.assisted.AssistedInject
+import io.element.android.anvilannotations.ContributesNode
+import io.element.android.libraries.architecture.NodeInputs
+import io.element.android.libraries.architecture.inputs
+import io.element.android.libraries.di.AppScope
+
+@ContributesNode(AppScope::class)
+class CreateAccountNode @AssistedInject constructor(
+    @Assisted buildContext: BuildContext,
+    @Assisted plugins: List<Plugin>,
+    presenterFactory: CreateAccountPresenter.Factory,
+) : Node(buildContext, plugins = plugins) {
+    data class Inputs(
+        val url: String,
+    ) : NodeInputs
+
+    private val presenter = presenterFactory.create(inputs<Inputs>().url)
+
+    @Composable
+    override fun View(modifier: Modifier) {
+        val state = presenter.present()
+        CreateAccountView(
+            state = state,
+            modifier = modifier,
+            onBackClick = ::navigateUp,
+        )
+    }
+}

features/login/impl/src/main/kotlin/io/element/android/features/login/impl/screens/createaccount/CreateAccountPresenter.kt

@@ -0,0 +1,83 @@
+/*
+ * Copyright 2023, 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Please see LICENSE in the repository root for full details.
+ */
+
+package io.element.android.features.login.impl.screens.createaccount
+
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.MutableState
+import androidx.compose.runtime.mutableIntStateOf
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.rememberCoroutineScope
+import dagger.assisted.Assisted
+import dagger.assisted.AssistedFactory
+import dagger.assisted.AssistedInject
+import io.element.android.features.login.impl.DefaultLoginUserStory
+import io.element.android.libraries.architecture.AsyncAction
+import io.element.android.libraries.architecture.Presenter
+import io.element.android.libraries.core.extensions.flatMap
+import io.element.android.libraries.core.meta.BuildMeta
+import io.element.android.libraries.matrix.api.auth.MatrixAuthenticationService
+import io.element.android.libraries.matrix.api.core.SessionId
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.launch
+
+class CreateAccountPresenter @AssistedInject constructor(
+    @Assisted private val url: String,
+    private val authenticationService: MatrixAuthenticationService,
+    private val defaultLoginUserStory: DefaultLoginUserStory,
+    private val messageParser: MessageParser,
+    private val buildMeta: BuildMeta,
+) : Presenter<CreateAccountState> {
+    @AssistedFactory
+    interface Factory {
+        fun create(url: String): CreateAccountPresenter
+    }
+
+    @Composable
+    override fun present(): CreateAccountState {
+        val coroutineScope = rememberCoroutineScope()
+        val pageProgress: MutableState<Int> = remember { mutableIntStateOf(0) }
+        val createAction: MutableState<AsyncAction<SessionId>> = remember { mutableStateOf(AsyncAction.Uninitialized) }
+
+        fun handleEvents(event: CreateAccountEvents) {
+            when (event) {
+                is CreateAccountEvents.SetPageProgress -> {
+                    pageProgress.value = event.progress
+                }
+                is CreateAccountEvents.OnMessageReceived -> {
+                    // Ignore unexpected message
+                    if (event.message.contains("isTrusted")) return
+                    coroutineScope.importSession(event.message, createAction)
+                }
+            }
+        }
+
+        return CreateAccountState(
+            url = url,
+            pageProgress = pageProgress.value,
+            isDebugBuild = buildMeta.isDebuggable,
+            createAction = createAction.value,
+            eventSink = ::handleEvents
+        )
+    }
+
+    private fun CoroutineScope.importSession(message: String, loggedInState: MutableState<AsyncAction<SessionId>>) = launch {
+        loggedInState.value = AsyncAction.Loading
+        runCatching {
+            messageParser.parse(message)
+        }.flatMap { externalSession ->
+            authenticationService.importCreatedSession(externalSession)
+        }.onSuccess { sessionId ->
+            // We will not navigate to the WaitList screen, so the login user story is done
+            defaultLoginUserStory.setLoginFlowIsDone(true)
+            loggedInState.value = AsyncAction.Success(sessionId)
+        }.onFailure { failure ->
+            loggedInState.value = AsyncAction.Failure(failure)
+        }
+    }
+}

features/login/impl/src/main/kotlin/io/element/android/features/login/impl/screens/createaccount/CreateAccountState.kt

@@ -0,0 +1,19 @@
+/*
+ * Copyright 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Please see LICENSE in the repository root for full details.
+ */
+
+package io.element.android.features.login.impl.screens.createaccount
+
+import io.element.android.libraries.architecture.AsyncAction
+import io.element.android.libraries.matrix.api.core.SessionId
+
+data class CreateAccountState(
+    val url: String,
+    val pageProgress: Int,
+    val createAction: AsyncAction<SessionId>,
+    val isDebugBuild: Boolean,
+    val eventSink: (CreateAccountEvents) -> Unit
+)

features/login/impl/src/main/kotlin/io/element/android/features/login/impl/screens/createaccount/CreateAccountStateProvider.kt

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2023, 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Please see LICENSE in the repository root for full details.
+ */
+
+package io.element.android.features.login.impl.screens.createaccount
+
+import androidx.compose.ui.tooling.preview.PreviewParameterProvider
+import io.element.android.libraries.architecture.AsyncAction
+import io.element.android.libraries.matrix.api.core.SessionId
+
+open class CreateAccountStateProvider : PreviewParameterProvider<CreateAccountState> {
+    override val values: Sequence<CreateAccountState>
+        get() = sequenceOf(
+            aCreateAccountState(),
+            aCreateAccountState(pageProgress = 33),
+            aCreateAccountState(createAction = AsyncAction.Loading),
+            aCreateAccountState(createAction = AsyncAction.Failure(Throwable("Failed to create account"))),
+        )
+}
+
+private fun aCreateAccountState(
+    pageProgress: Int = 100,
+    createAction: AsyncAction<SessionId> = AsyncAction.Uninitialized,
+) = CreateAccountState(
+    url = "https://example.com",
+    isDebugBuild = true,
+    pageProgress = pageProgress,
+    createAction = createAction,
+    eventSink = {}
+)

features/login/impl/src/main/kotlin/io/element/android/features/login/impl/screens/createaccount/CreateAccountView.kt

@@ -0,0 +1,166 @@
+/*
+ * Copyright 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Please see LICENSE in the repository root for full details.
+ */
+
+package io.element.android.features.login.impl.screens.createaccount
+
+import android.annotation.SuppressLint
+import android.view.ViewGroup
+import android.webkit.WebChromeClient
+import android.webkit.WebView
+import androidx.compose.animation.AnimatedVisibility
+import androidx.compose.animation.fadeIn
+import androidx.compose.animation.fadeOut
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.consumeWindowInsets
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.padding
+import androidx.compose.material3.ExperimentalMaterial3Api
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.platform.LocalInspectionMode
+import androidx.compose.ui.res.stringResource
+import androidx.compose.ui.tooling.preview.PreviewParameter
+import androidx.compose.ui.unit.dp
+import androidx.compose.ui.viewinterop.AndroidView
+import io.element.android.compound.theme.ElementTheme
+import io.element.android.features.login.impl.R
+import io.element.android.libraries.designsystem.components.async.AsyncActionView
+import io.element.android.libraries.designsystem.components.button.BackButton
+import io.element.android.libraries.designsystem.preview.ElementPreview
+import io.element.android.libraries.designsystem.preview.PreviewsDayNight
+import io.element.android.libraries.designsystem.theme.aliasScreenTitle
+import io.element.android.libraries.designsystem.theme.components.LinearProgressIndicator
+import io.element.android.libraries.designsystem.theme.components.Scaffold
+import io.element.android.libraries.designsystem.theme.components.Text
+import io.element.android.libraries.designsystem.theme.components.TopAppBar
+import io.element.android.libraries.designsystem.theme.progressIndicatorTrackColor
+
+@OptIn(ExperimentalMaterial3Api::class)
+@Composable
+fun CreateAccountView(
+    state: CreateAccountState,
+    onBackClick: () -> Unit,
+    modifier: Modifier = Modifier,
+) {
+    Scaffold(
+        modifier = modifier,
+        topBar = {
+            TopAppBar(
+                title = {
+                    Text(
+                        stringResource(R.string.screen_create_account_title),
+                        style = ElementTheme.typography.aliasScreenTitle,
+                    )
+                },
+                navigationIcon = {
+                    BackButton(onClick = onBackClick)
+                },
+            )
+        }
+    ) { contentPadding ->
+        Box(
+            modifier = Modifier
+                .padding(contentPadding)
+                .consumeWindowInsets(contentPadding)
+                .fillMaxSize()
+        ) {
+            CreateAccountWebView(
+                modifier = Modifier
+                    .fillMaxSize(),
+                state = state,
+                onWebViewCreate = { webView ->
+                    WebViewMessageInterceptor(webView, state.isDebugBuild) {
+                        state.eventSink(CreateAccountEvents.OnMessageReceived(it))
+                    }
+                }
+            )
+            AnimatedVisibility(
+                visible = state.pageProgress != 100,
+                // Disable enter animation
+                enter = fadeIn(initialAlpha = 1f),
+                exit = fadeOut(),
+            ) {
+                LinearProgressIndicator(
+                    modifier = Modifier
+                        .fillMaxWidth()
+                        .height(2.dp),
+                    progress = { state.pageProgress / 100f },
+                    trackColor = ElementTheme.colors.progressIndicatorTrackColor,
+                )
+            }
+        }
+    }
+
+    AsyncActionView(
+        async = state.createAction,
+        onSuccess = {},
+        onErrorDismiss = onBackClick,
+        onRetry = null
+    )
+}
+
+@Composable
+private fun CreateAccountWebView(
+    state: CreateAccountState,
+    onWebViewCreate: (WebView) -> Unit,
+    modifier: Modifier = Modifier,
+) {
+    if (LocalInspectionMode.current) {
+        Box(modifier = modifier, contentAlignment = Alignment.Center) {
+            Text("WebView - can't be previewed")
+        }
+    } else {
+        AndroidView(
+            modifier = modifier,
+            factory = { context ->
+                WebView(context).apply {
+                    onWebViewCreate(this)
+                    setup(state)
+                }
+            },
+            update = { webView ->
+                if (webView.url != state.url) {
+                    webView.loadUrl(state.url)
+                }
+            },
+            onRelease = { webView ->
+                webView.destroy()
+            }
+        )
+    }
+}
+
+@SuppressLint("SetJavaScriptEnabled")
+private fun WebView.setup(state: CreateAccountState) {
+    layoutParams = ViewGroup.LayoutParams(
+        ViewGroup.LayoutParams.MATCH_PARENT,
+        ViewGroup.LayoutParams.MATCH_PARENT
+    )
+    with(settings) {
+        javaScriptEnabled = true
+        domStorageEnabled = true
+    }
+
+    webChromeClient = object : WebChromeClient() {
+        override fun onProgressChanged(view: WebView?, newProgress: Int) {
+            super.onProgressChanged(view, newProgress)
+            state.eventSink(CreateAccountEvents.SetPageProgress(newProgress))
+        }
+    }
+}
+
+@PreviewsDayNight
+@Composable
+internal fun CreateAccountViewPreview(@PreviewParameter(CreateAccountStateProvider::class) state: CreateAccountState) = ElementPreview {
+    CreateAccountView(
+        state = state,
+        onBackClick = {},
+    )
+}

features/login/impl/src/main/kotlin/io/element/android/features/login/impl/screens/createaccount/MessageParser.kt

@@ -0,0 +1,45 @@
+/*
+ * Copyright 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Please see LICENSE in the repository root for full details.
+ */
+
+package io.element.android.features.login.impl.screens.createaccount
+
+import com.squareup.anvil.annotations.ContributesBinding
+import io.element.android.features.login.impl.accountprovider.AccountProviderDataSource
+import io.element.android.libraries.di.AppScope
+import io.element.android.libraries.matrix.api.auth.external.ExternalSession
+import kotlinx.serialization.json.Json
+import javax.inject.Inject
+
+interface MessageParser {
+    /**
+     * Parse the message and return the ExternalSession object, or
+     * throw an exception if the message is invalid.
+     */
+    fun parse(message: String): ExternalSession
+}
+
+@ContributesBinding(AppScope::class)
+class DefaultMessageParser @Inject constructor(
+    private val accountProviderDataSource: AccountProviderDataSource,
+) : MessageParser {
+    override fun parse(message: String): ExternalSession {
+        val parser = Json { ignoreUnknownKeys = true }
+        val response = parser.decodeFromString(MobileRegistrationResponse.serializer(), message)
+        val userId = response.userId ?: error("No user ID in response")
+        val homeServer = response.homeServer ?: accountProviderDataSource.flow().value.url
+        val accessToken = response.accessToken ?: error("No access token in response")
+        val deviceId = response.deviceId ?: error("No device ID in response")
+        return ExternalSession(
+            userId = userId,
+            homeserverUrl = homeServer,
+            accessToken = accessToken,
+            deviceId = deviceId,
+            refreshToken = null,
+            slidingSyncProxy = null
+        )
+    }
+}

features/login/impl/src/main/kotlin/io/element/android/features/login/impl/screens/createaccount/MobileRegistrationResponse.kt

@@ -0,0 +1,27 @@
+/*
+ * Copyright 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Please see LICENSE in the repository root for full details.
+ */
+
+package io.element.android.features.login.impl.screens.createaccount
+
+import kotlinx.serialization.SerialName
+import kotlinx.serialization.Serializable
+
+/**
+ * For ref:
+ * https://github.com/element-hq/matrix-react-sdk/pull/42/files#diff-2bbba5a742004fd4e924a639ded444279f66f7ad890cb669fbc91ac6b8638c64R56
+ */
+@Serializable
+data class MobileRegistrationResponse(
+    @SerialName("user_id")
+    val userId: String? = null,
+    @SerialName("home_server")
+    val homeServer: String? = null,
+    @SerialName("access_token")
+    val accessToken: String? = null,
+    @SerialName("device_id")
+    val deviceId: String? = null,
+)

features/login/impl/src/main/kotlin/io/element/android/features/login/impl/screens/createaccount/WebViewMessageInterceptor.kt

@@ -0,0 +1,84 @@
+/*
+ * Copyright 2023, 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Please see LICENSE in the repository root for full details.
+ */
+
+package io.element.android.features.login.impl.screens.createaccount
+
+import android.graphics.Bitmap
+import android.webkit.JavascriptInterface
+import android.webkit.WebView
+import android.webkit.WebViewClient
+import androidx.webkit.WebViewCompat
+import androidx.webkit.WebViewFeature
+
+class WebViewMessageInterceptor(
+    webView: WebView,
+    private val debugLog: Boolean,
+    private val onMessage: (String) -> Unit,
+) {
+    companion object {
+        // We call both the WebMessageListener and the JavascriptInterface objects in JS with this
+        // 'listenerName' so they can both receive the data from the WebView when
+        // `${LISTENER_NAME}.postMessage(...)` is called
+        const val LISTENER_NAME = "elementX"
+    }
+
+    init {
+        webView.webViewClient = object : WebViewClient() {
+            override fun onPageStarted(view: WebView?, url: String?, favicon: Bitmap?) {
+                super.onPageStarted(view, url, favicon)
+
+                // We inject this JS code when the page starts loading to attach a message listener to the window.
+                // This listener will receive both messages:
+                // - EC widget API -> Element X (message.data.api == "fromWidget")
+                // - Element X -> EC widget API (message.data.api == "toWidget"), we should ignore these
+                view?.evaluateJavascript(
+                    """
+                        window.addEventListener(
+                          "mobileregistrationresponse",
+                          (event) => {
+                            let json = JSON.stringify(event.detail)
+                            ${"console.log('message sent: ' + json);".takeIf { debugLog }}
+                            $LISTENER_NAME.postMessage(json);
+                          },
+                          false,
+                        );
+                    """.trimIndent(),
+                    null
+                )
+            }
+        }
+
+        // Use WebMessageListener if supported, otherwise use JavascriptInterface
+        if (WebViewFeature.isFeatureSupported(WebViewFeature.WEB_MESSAGE_LISTENER)) {
+            // Create a WebMessageListener, which will receive messages from the WebView and reply to them
+            val webMessageListener = WebViewCompat.WebMessageListener { _, message, _, _, _ ->
+                onMessageReceived(message.data)
+            }
+            WebViewCompat.addWebMessageListener(
+                webView,
+                LISTENER_NAME,
+                setOf("*"),
+                webMessageListener
+            )
+        } else {
+            webView.addJavascriptInterface(
+                object {
+                    @JavascriptInterface
+                    fun postMessage(json: String?) {
+                        onMessageReceived(json)
+                    }
+                },
+                LISTENER_NAME,
+            )
+        }
+    }
+
+    private fun onMessageReceived(json: String?) {
+        // Here is where we would handle the messages from the WebView, passing them to the listener
+        json?.let { onMessage(it) }
+    }
+}

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

@@ -0,0 +1,50 @@
+/*
+ * Copyright 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Please see LICENSE in the repository root for full details.
+ */
+
+package io.element.android.features.login.impl.web
+
+import android.net.Uri
+import com.squareup.anvil.annotations.ContributesBinding
+import io.element.android.features.login.impl.resolver.network.WellknownAPI
+import io.element.android.features.login.impl.screens.createaccount.AccountCreationNotSupported
+import io.element.android.libraries.di.AppScope
+import io.element.android.libraries.network.RetrofitFactory
+import java.net.HttpURLConnection
+import javax.inject.Inject
+
+interface WebClientUrlForAuthenticationRetriever {
+    suspend fun retrieve(homeServerUrl: String): String
+}
+
+@ContributesBinding(AppScope::class)
+class DefaultWebClientUrlForAuthenticationRetriever @Inject constructor(
+    private val retrofitFactory: RetrofitFactory,
+) : WebClientUrlForAuthenticationRetriever {
+    override suspend fun retrieve(homeServerUrl: String): String {
+        val wellknownApi = retrofitFactory.create(homeServerUrl)
+            .create(WellknownAPI::class.java)
+        val result = try {
+            wellknownApi.getElementWellKnown()
+        } catch (e: Exception) {
+            throw when {
+                e is retrofit2.HttpException &&
+                    e.code() == HttpURLConnection.HTTP_NOT_FOUND -> AccountCreationNotSupported()
+                else -> e
+            }
+        }
+        val registrationHelperUrl = result.registrationHelperUrl
+        return if (registrationHelperUrl != null) {
+            Uri.parse(registrationHelperUrl)
+                .buildUpon()
+                .appendQueryParameter("hs_url", homeServerUrl)
+                .build()
+                .toString()
+        } else {
+            throw AccountCreationNotSupported()
+        }
+    }
+}

features/login/impl/src/main/res/values/localazy.xml

@@ -21,6 +21,7 @@
   <string name="screen_change_server_form_notice">"You can only connect to an existing server that supports sliding sync. Your homeserver admin will need to configure it. %1$s"</string>
   <string name="screen_change_server_subtitle">"What is the address of your server?"</string>
   <string name="screen_change_server_title">"Select your server"</string>
+  <string name="screen_create_account_title">"Create account"</string>
   <string name="screen_login_error_deactivated_account">"This account has been deactivated."</string>
   <string name="screen_login_error_invalid_credentials">"Incorrect username and/or password"</string>
   <string name="screen_login_error_invalid_user_id">"This is not a valid user identifier. Expected format: ‘@user:homeserver.org’"</string>

features/login/impl/src/test/kotlin/io/element/android/features/login/impl/screens/confirmaccountprovider/ConfirmAccountProviderPresenterTest.kt

@@ -13,7 +13,10 @@ import app.cash.turbine.test
 import com.google.common.truth.Truth.assertThat
 import io.element.android.features.login.impl.DefaultLoginUserStory
 import io.element.android.features.login.impl.accountprovider.AccountProviderDataSource
+import io.element.android.features.login.impl.screens.createaccount.AccountCreationNotSupported
 import io.element.android.features.login.impl.util.defaultAccountProvider
+import io.element.android.features.login.impl.web.FakeWebClientUrlForAuthenticationRetriever
+import io.element.android.features.login.impl.web.WebClientUrlForAuthenticationRetriever
 import io.element.android.libraries.architecture.AsyncData
 import io.element.android.libraries.matrix.api.auth.MatrixAuthenticationService
 import io.element.android.libraries.matrix.test.A_HOMESERVER
@@ -255,17 +258,109 @@ class ConfirmAccountProviderPresenterTest {
         }
     }
 
+    @Test
+    fun `present - confirm account creation without oidc and without url generates an error`() = runTest {
+        val authenticationService = FakeMatrixAuthenticationService()
+        authenticationService.givenHomeserver(A_HOMESERVER)
+        val presenter = createConfirmAccountProviderPresenter(
+            params = ConfirmAccountProviderPresenter.Params(isAccountCreation = true),
+            matrixAuthenticationService = authenticationService,
+            webClientUrlForAuthenticationRetriever = FakeWebClientUrlForAuthenticationRetriever {
+                throw AccountCreationNotSupported()
+            },
+        )
+        moleculeFlow(RecompositionMode.Immediate) {
+            presenter.present()
+        }.test {
+            val initialState = awaitItem()
+            initialState.eventSink(ConfirmAccountProviderEvents.Continue)
+            skipItems(1) // Loading
+            // Check an error was returned
+            val submittedState = awaitItem()
+            assertThat(submittedState.loginFlow.errorOrNull()).isInstanceOf(AccountCreationNotSupported::class.java)
+            // Assert the error is then cleared
+            submittedState.eventSink(ConfirmAccountProviderEvents.ClearError)
+            val clearedState = awaitItem()
+            assertThat(clearedState.loginFlow).isEqualTo(AsyncData.Uninitialized)
+        }
+    }
+
+    @Test
+    fun `present - confirm account creation with oidc is successful`() = runTest {
+        val authenticationService = FakeMatrixAuthenticationService()
+        authenticationService.givenHomeserver(A_HOMESERVER_OIDC)
+        val presenter = createConfirmAccountProviderPresenter(
+            params = ConfirmAccountProviderPresenter.Params(isAccountCreation = true),
+            matrixAuthenticationService = authenticationService,
+        )
+        moleculeFlow(RecompositionMode.Immediate) {
+            presenter.present()
+        }.test {
+            val initialState = awaitItem()
+            initialState.eventSink(ConfirmAccountProviderEvents.Continue)
+            skipItems(1) // Loading
+            val submittedState = awaitItem()
+            assertThat(submittedState.loginFlow).isInstanceOf(AsyncData.Success::class.java)
+            assertThat(submittedState.loginFlow.dataOrNull()).isInstanceOf(LoginFlow.OidcFlow::class.java)
+        }
+    }
+
+    @Test
+    fun `present - confirm account creation with oidc and url continues with oidc`() = runTest {
+        val aUrl = "aUrl"
+        val authenticationService = FakeMatrixAuthenticationService()
+        authenticationService.givenHomeserver(A_HOMESERVER_OIDC)
+        val presenter = createConfirmAccountProviderPresenter(
+            params = ConfirmAccountProviderPresenter.Params(isAccountCreation = true),
+            matrixAuthenticationService = authenticationService,
+            webClientUrlForAuthenticationRetriever = FakeWebClientUrlForAuthenticationRetriever { aUrl },
+        )
+        moleculeFlow(RecompositionMode.Immediate) {
+            presenter.present()
+        }.test {
+            val initialState = awaitItem()
+            initialState.eventSink(ConfirmAccountProviderEvents.Continue)
+            skipItems(1) // Loading
+            val submittedState = awaitItem()
+            assertThat(submittedState.loginFlow).isInstanceOf(AsyncData.Success::class.java)
+            assertThat(submittedState.loginFlow.dataOrNull()).isInstanceOf(LoginFlow.OidcFlow::class.java)
+        }
+    }
+
+    @Test
+    fun `present - confirm account creation without oidc and with url continuing with url`() = runTest {
+        val aUrl = "aUrl"
+        val authenticationService = FakeMatrixAuthenticationService()
+        authenticationService.givenHomeserver(A_HOMESERVER)
+        val presenter = createConfirmAccountProviderPresenter(
+            params = ConfirmAccountProviderPresenter.Params(isAccountCreation = true),
+            matrixAuthenticationService = authenticationService,
+            webClientUrlForAuthenticationRetriever = FakeWebClientUrlForAuthenticationRetriever { aUrl },
+        )
+        moleculeFlow(RecompositionMode.Immediate) {
+            presenter.present()
+        }.test {
+            val initialState = awaitItem()
+            initialState.eventSink(ConfirmAccountProviderEvents.Continue)
+            skipItems(1) // Loading
+            val submittedState = awaitItem()
+            assertThat(submittedState.loginFlow.dataOrNull()).isEqualTo(LoginFlow.AccountCreationFlow(aUrl))
+        }
+    }
+
     private fun createConfirmAccountProviderPresenter(
         params: ConfirmAccountProviderPresenter.Params = ConfirmAccountProviderPresenter.Params(isAccountCreation = false),
         accountProviderDataSource: AccountProviderDataSource = AccountProviderDataSource(),
         matrixAuthenticationService: MatrixAuthenticationService = FakeMatrixAuthenticationService(),
         defaultOidcActionFlow: DefaultOidcActionFlow = DefaultOidcActionFlow(),
         defaultLoginUserStory: DefaultLoginUserStory = DefaultLoginUserStory(),
+        webClientUrlForAuthenticationRetriever: WebClientUrlForAuthenticationRetriever = FakeWebClientUrlForAuthenticationRetriever(),
     ) = ConfirmAccountProviderPresenter(
         params = params,
         accountProviderDataSource = accountProviderDataSource,
         authenticationService = matrixAuthenticationService,
         oidcActionFlow = defaultOidcActionFlow,
         defaultLoginUserStory = defaultLoginUserStory,
+        webClientUrlForAuthenticationRetriever = webClientUrlForAuthenticationRetriever
     )
 }

features/login/impl/src/test/kotlin/io/element/android/features/login/impl/screens/createaccount/CreateAccountPresenterTest.kt

@@ -0,0 +1,145 @@
+/*
+ * Copyright 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Please see LICENSE in the repository root for full details.
+ */
+
+package io.element.android.features.login.impl.screens.createaccount
+
+import app.cash.molecule.RecompositionMode
+import app.cash.molecule.moleculeFlow
+import app.cash.turbine.test
+import com.google.common.truth.Truth.assertThat
+import io.element.android.features.login.impl.DefaultLoginUserStory
+import io.element.android.libraries.architecture.AsyncAction
+import io.element.android.libraries.core.meta.BuildMeta
+import io.element.android.libraries.matrix.api.auth.MatrixAuthenticationService
+import io.element.android.libraries.matrix.api.auth.external.ExternalSession
+import io.element.android.libraries.matrix.test.AN_EXCEPTION
+import io.element.android.libraries.matrix.test.A_SESSION_ID
+import io.element.android.libraries.matrix.test.auth.FakeMatrixAuthenticationService
+import io.element.android.libraries.matrix.test.core.aBuildMeta
+import io.element.android.tests.testutils.WarmUpRule
+import io.element.android.tests.testutils.lambda.lambdaRecorder
+import io.element.android.tests.testutils.lambda.value
+import kotlinx.coroutines.test.runTest
+import org.junit.Rule
+import org.junit.Test
+
+class CreateAccountPresenterTest {
+    @get:Rule
+    val warmUpRule = WarmUpRule()
+
+    @Test
+    fun `present - initial state`() = runTest {
+        val presenter = createPresenter()
+        moleculeFlow(RecompositionMode.Immediate) {
+            presenter.present()
+        }.test {
+            val initialState = awaitItem()
+            assertThat(initialState.url).isEqualTo("aUrl")
+            assertThat(initialState.pageProgress).isEqualTo(0)
+            assertThat(initialState.createAction).isEqualTo(AsyncAction.Uninitialized)
+            assertThat(initialState.isDebugBuild).isTrue()
+        }
+    }
+
+    @Test
+    fun `present - set up progress update the state`() = runTest {
+        val presenter = createPresenter()
+        moleculeFlow(RecompositionMode.Immediate) {
+            presenter.present()
+        }.test {
+            val initialState = awaitItem()
+            initialState.eventSink(CreateAccountEvents.SetPageProgress(33))
+            assertThat(awaitItem().pageProgress).isEqualTo(33)
+        }
+    }
+
+    @Test
+    fun `present - receiving a message not able to be parsed change the state to error`() = runTest {
+        val presenter = createPresenter(
+            messageParser = FakeMessageParser { error("An error") }
+        )
+        moleculeFlow(RecompositionMode.Immediate) {
+            presenter.present()
+        }.test {
+            val initialState = awaitItem()
+            initialState.eventSink(CreateAccountEvents.OnMessageReceived(""))
+            assertThat(awaitItem().createAction).isInstanceOf(AsyncAction.Failure::class.java)
+        }
+    }
+
+    @Test
+    fun `present - receiving a message containing isTrusted is ignored`() = runTest {
+        val presenter = createPresenter()
+        moleculeFlow(RecompositionMode.Immediate) {
+            presenter.present()
+        }.test {
+            val initialState = awaitItem()
+            initialState.eventSink(CreateAccountEvents.OnMessageReceived("isTrusted"))
+        }
+    }
+
+    @Test
+    fun `present - receiving a message able to be parsed change the state to success`() = runTest {
+        val defaultLoginUserStory = DefaultLoginUserStory()
+        defaultLoginUserStory.setLoginFlowIsDone(false)
+        assertThat(defaultLoginUserStory.loginFlowIsDone.value).isFalse()
+        val lambda = lambdaRecorder<String, ExternalSession> { _ -> anExternalSession() }
+        val presenter = createPresenter(
+            authenticationService = FakeMatrixAuthenticationService(
+                importCreatedSessionLambda = { Result.success(A_SESSION_ID) }
+            ),
+            messageParser = FakeMessageParser(lambda),
+            defaultLoginUserStory = defaultLoginUserStory,
+        )
+        moleculeFlow(RecompositionMode.Immediate) {
+            presenter.present()
+        }.test {
+            val initialState = awaitItem()
+            initialState.eventSink(CreateAccountEvents.OnMessageReceived("aMessage"))
+            assertThat(awaitItem().createAction.isLoading()).isTrue()
+            assertThat(awaitItem().createAction.dataOrNull()).isEqualTo(A_SESSION_ID)
+        }
+        lambda.assertions().isCalledOnce().with(value("aMessage"))
+        assertThat(defaultLoginUserStory.loginFlowIsDone.value).isTrue()
+    }
+
+    @Test
+    fun `present - receiving a message able to be parsed but error in importing change the state to error`() = runTest {
+        val defaultLoginUserStory = DefaultLoginUserStory()
+        defaultLoginUserStory.setLoginFlowIsDone(false)
+        assertThat(defaultLoginUserStory.loginFlowIsDone.value).isFalse()
+        val presenter = createPresenter(
+            authenticationService = FakeMatrixAuthenticationService(
+                importCreatedSessionLambda = { Result.failure(AN_EXCEPTION) }
+            ),
+            messageParser = FakeMessageParser { anExternalSession() }
+        )
+        moleculeFlow(RecompositionMode.Immediate) {
+            presenter.present()
+        }.test {
+            val initialState = awaitItem()
+            initialState.eventSink(CreateAccountEvents.OnMessageReceived(""))
+            assertThat(awaitItem().createAction.isLoading()).isTrue()
+            assertThat(awaitItem().createAction.errorOrNull()).isNotNull()
+        }
+        assertThat(defaultLoginUserStory.loginFlowIsDone.value).isFalse()
+    }
+
+    private fun createPresenter(
+        url: String = "aUrl",
+        authenticationService: MatrixAuthenticationService = FakeMatrixAuthenticationService(),
+        defaultLoginUserStory: DefaultLoginUserStory = DefaultLoginUserStory(),
+        messageParser: MessageParser = FakeMessageParser(),
+        buildMeta: BuildMeta = aBuildMeta(),
+    ) = CreateAccountPresenter(
+        url = url,
+        authenticationService = authenticationService,
+        defaultLoginUserStory = defaultLoginUserStory,
+        messageParser = messageParser,
+        buildMeta = buildMeta,
+    )
+}

features/login/impl/src/test/kotlin/io/element/android/features/login/impl/screens/createaccount/DefaultMessageParserTest.kt

@@ -0,0 +1,84 @@
+/*
+ * Copyright 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Please see LICENSE in the repository root for full details.
+ */
+
+package io.element.android.features.login.impl.screens.createaccount
+
+import com.google.common.truth.Truth.assertThat
+import io.element.android.features.login.impl.accountprovider.AccountProviderDataSource
+import io.element.android.features.login.impl.util.defaultAccountProvider
+import io.element.android.libraries.matrix.api.auth.external.ExternalSession
+import kotlinx.serialization.SerializationException
+import org.junit.Assert.assertThrows
+import org.junit.Test
+
+class DefaultMessageParserTest {
+    private val validMessage = """
+        {
+            "user_id": "user_id",
+            "home_server": "home_server",
+            "access_token": "access_token",
+            "device_id": "device_id"
+        }
+   """.trimIndent()
+
+    @Test
+    fun `DefaultMessageParser is able to parse correct message`() {
+        val sut = DefaultMessageParser(
+            AccountProviderDataSource()
+        )
+        assertThat(sut.parse(validMessage)).isEqualTo(
+            anExternalSession(
+                homeserverUrl = "home_server",
+            )
+        )
+    }
+
+    @Test
+    fun `DefaultMessageParser should throw Exception in case of error`() {
+        val sut = DefaultMessageParser(
+            AccountProviderDataSource()
+        )
+        // kotlinx.serialization.json.internal.JsonDecodingException
+        assertThrows(SerializationException::class.java) { sut.parse("invalid json") }
+        // missing userId
+        assertThrows(IllegalStateException::class.java) { sut.parse(validMessage.replace(""""user_id": "user_id",""", "")) }
+        // missing accessToken
+        assertThrows(IllegalStateException::class.java) { sut.parse(validMessage.replace(""""access_token": "access_token",""", "")) }
+        // missing deviceId
+        assertThrows(IllegalStateException::class.java) {
+            sut.parse(
+                validMessage
+                    .replace(""""access_token": "access_token",""", """"access_token": "access_token"""")
+                    .replace(""""device_id": "device_id"""", "")
+            )
+        }
+    }
+
+    @Test
+    fun `DefaultMessageParser should be successful even is homeserver url is missing`() {
+        val sut = DefaultMessageParser(
+            AccountProviderDataSource()
+        )
+        // missing homeServer
+        assertThat(sut.parse(validMessage.replace(""""home_server": "home_server",""", ""))).isEqualTo(
+            anExternalSession(
+                homeserverUrl = defaultAccountProvider.url,
+            )
+        )
+    }
+}
+
+internal fun anExternalSession(
+    homeserverUrl: String = "home_server",
+) = ExternalSession(
+    userId = "user_id",
+    homeserverUrl = homeserverUrl,
+    accessToken = "access_token",
+    deviceId = "device_id",
+    refreshToken = null,
+    slidingSyncProxy = null
+)

features/login/impl/src/test/kotlin/io/element/android/features/login/impl/screens/createaccount/FakeMessageParser.kt

@@ -0,0 +1,19 @@
+/*
+ * Copyright 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Please see LICENSE in the repository root for full details.
+ */
+
+package io.element.android.features.login.impl.screens.createaccount
+
+import io.element.android.libraries.matrix.api.auth.external.ExternalSession
+import io.element.android.tests.testutils.lambda.lambdaError
+
+class FakeMessageParser(
+    private val parseResult: (String) -> ExternalSession = { lambdaError() }
+) : MessageParser {
+    override fun parse(message: String): ExternalSession {
+        return parseResult(message)
+    }
+}

features/login/impl/src/test/kotlin/io/element/android/features/login/impl/web/FakeWebClientUrlForAuthenticationRetriever.kt

@@ -0,0 +1,18 @@
+/*
+ * Copyright 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Please see LICENSE in the repository root for full details.
+ */
+
+package io.element.android.features.login.impl.web
+
+import io.element.android.tests.testutils.lambda.lambdaError
+
+class FakeWebClientUrlForAuthenticationRetriever(
+    private val retrieveLambda: suspend (homeServerUrl: String) -> String = { lambdaError() }
+) : WebClientUrlForAuthenticationRetriever {
+    override suspend fun retrieve(homeServerUrl: String): String {
+        return retrieveLambda(homeServerUrl)
+    }
+}

libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/auth/MatrixAuthenticationService.kt

@@ -9,6 +9,7 @@ package io.element.android.libraries.matrix.api.auth
 
 import io.element.android.libraries.matrix.api.MatrixClient
 import io.element.android.libraries.matrix.api.MatrixClientProvider
+import io.element.android.libraries.matrix.api.auth.external.ExternalSession
 import io.element.android.libraries.matrix.api.auth.qrlogin.MatrixQrCodeLoginData
 import io.element.android.libraries.matrix.api.auth.qrlogin.QrCodeLoginStep
 import io.element.android.libraries.matrix.api.core.SessionId
@@ -30,6 +31,11 @@ interface MatrixAuthenticationService {
     suspend fun setHomeserver(homeserver: String): Result<Unit>
     suspend fun login(username: String, password: String): Result<SessionId>
 
+    /**
+     * Import a session that was created using another client, for instance Element Web.
+     */
+    suspend fun importCreatedSession(externalSession: ExternalSession): Result<SessionId>
+
     /*
      * OIDC part.
      */

libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/auth/external/ExternalSession.kt

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2024 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Please see LICENSE in the repository root for full details.
+ */
+
+package io.element.android.libraries.matrix.api.auth.external
+
+/***
+ * Represents a session data of a session created by another client.
+ */
+data class ExternalSession(
+    val userId: String,
+    val deviceId: String,
+    val accessToken: String,
+    val refreshToken: String?,
+    val homeserverUrl: String,
+    val slidingSyncProxy: String?
+)

libraries/matrix/impl/src/main/kotlin/io/element/android/libraries/matrix/impl/auth/RustMatrixAuthenticationService.kt

@@ -17,6 +17,7 @@ import io.element.android.libraries.matrix.api.MatrixClient
 import io.element.android.libraries.matrix.api.auth.MatrixAuthenticationService
 import io.element.android.libraries.matrix.api.auth.MatrixHomeServerDetails
 import io.element.android.libraries.matrix.api.auth.OidcDetails
+import io.element.android.libraries.matrix.api.auth.external.ExternalSession
 import io.element.android.libraries.matrix.api.auth.qrlogin.MatrixQrCodeLoginData
 import io.element.android.libraries.matrix.api.auth.qrlogin.QrCodeLoginStep
 import io.element.android.libraries.matrix.api.core.SessionId
@@ -160,6 +161,23 @@ class RustMatrixAuthenticationService @Inject constructor(
             }
         }
 
+    override suspend fun importCreatedSession(externalSession: ExternalSession): Result<SessionId> =
+        withContext(coroutineDispatchers.io) {
+            runCatching {
+                currentClient ?: error("You need to call `setHomeserver()` first")
+                val currentSessionPaths = sessionPaths ?: error("You need to call `setHomeserver()` first")
+                val sessionData = externalSession.toSessionData(
+                    isTokenValid = true,
+                    loginType = LoginType.PASSWORD,
+                    passphrase = pendingPassphrase,
+                    sessionPaths = currentSessionPaths,
+                )
+                clear()
+                sessionStore.storeData(sessionData)
+                SessionId(sessionData.userId)
+            }
+        }
+
     private var pendingOidcAuthorizationData: OidcAuthorizationData? = null
 
     override suspend fun getOidcUrl(): Result<OidcDetails> {

libraries/matrix/impl/src/main/kotlin/io/element/android/libraries/matrix/impl/mapper/Session.kt

@@ -7,6 +7,7 @@
 
 package io.element.android.libraries.matrix.impl.mapper
 
+import io.element.android.libraries.matrix.api.auth.external.ExternalSession
 import io.element.android.libraries.matrix.impl.paths.SessionPaths
 import io.element.android.libraries.sessionstorage.api.LoginType
 import io.element.android.libraries.sessionstorage.api.SessionData
@@ -35,3 +36,24 @@ internal fun Session.toSessionData(
     sessionPath = sessionPaths.fileDirectory.absolutePath,
     cachePath = sessionPaths.cacheDirectory.absolutePath,
 )
+
+internal fun ExternalSession.toSessionData(
+    isTokenValid: Boolean,
+    loginType: LoginType,
+    passphrase: String?,
+    sessionPaths: SessionPaths,
+) = SessionData(
+    userId = userId,
+    deviceId = deviceId,
+    accessToken = accessToken,
+    refreshToken = refreshToken,
+    homeserverUrl = homeserverUrl,
+    oidcData = null,
+    slidingSyncProxy = slidingSyncProxy,
+    loginTimestamp = Date(),
+    isTokenValid = isTokenValid,
+    loginType = loginType,
+    passphrase = passphrase,
+    sessionPath = sessionPaths.fileDirectory.absolutePath,
+    cachePath = sessionPaths.cacheDirectory.absolutePath,
+)

libraries/matrix/test/src/main/kotlin/io/element/android/libraries/matrix/test/auth/FakeMatrixAuthenticationService.kt

@@ -11,12 +11,14 @@ import io.element.android.libraries.matrix.api.MatrixClient
 import io.element.android.libraries.matrix.api.auth.MatrixAuthenticationService
 import io.element.android.libraries.matrix.api.auth.MatrixHomeServerDetails
 import io.element.android.libraries.matrix.api.auth.OidcDetails
+import io.element.android.libraries.matrix.api.auth.external.ExternalSession
 import io.element.android.libraries.matrix.api.auth.qrlogin.MatrixQrCodeLoginData
 import io.element.android.libraries.matrix.api.auth.qrlogin.QrCodeLoginStep
 import io.element.android.libraries.matrix.api.core.SessionId
 import io.element.android.libraries.matrix.test.A_SESSION_ID
 import io.element.android.libraries.matrix.test.A_USER_ID
 import io.element.android.libraries.sessionstorage.api.LoggedInState
+import io.element.android.tests.testutils.lambda.lambdaError
 import io.element.android.tests.testutils.lambda.lambdaRecorder
 import io.element.android.tests.testutils.simulateLongTask
 import kotlinx.coroutines.flow.Flow
@@ -30,6 +32,7 @@ class FakeMatrixAuthenticationService(
     var matrixClientResult: ((SessionId) -> Result<MatrixClient>)? = null,
     var loginWithQrCodeResult: (qrCodeData: MatrixQrCodeLoginData, progress: (QrCodeLoginStep) -> Unit) -> Result<SessionId> =
         lambdaRecorder<MatrixQrCodeLoginData, (QrCodeLoginStep) -> Unit, Result<SessionId>> { _, _ -> Result.success(A_SESSION_ID) },
+    private val importCreatedSessionLambda: (ExternalSession) -> Result<SessionId> = { lambdaError() }
 ) : MatrixAuthenticationService {
     private val homeserver = MutableStateFlow<MatrixHomeServerDetails?>(null)
     private var oidcError: Throwable? = null
@@ -73,6 +76,10 @@ class FakeMatrixAuthenticationService(
         loginError?.let { Result.failure(it) } ?: Result.success(A_USER_ID)
     }
 
+    override suspend fun importCreatedSession(externalSession: ExternalSession): Result<SessionId> = simulateLongTask {
+        return importCreatedSessionLambda(externalSession)
+    }
+
     override suspend fun getOidcUrl(): Result<OidcDetails> = simulateLongTask {
         oidcError?.let { Result.failure(it) } ?: Result.success(A_OIDC_DATA)
     }

libraries/ui-strings/src/main/res/values-el/translations.xml

@@ -273,7 +273,6 @@
   <string name="invite_friends_text">"Γεια, μίλα μου στην εφαρμογή %1$s :%2$s"</string>
   <string name="login_initial_device_name_android">"%1$s Android"</string>
   <string name="preference_rageshake">"Κούνησε δυνατά τη συσκευή σου για να αναφέρεις κάποιο σφάλμα"</string>
-  <string name="screen_create_account_title">"Δημιουργία λογαριασμού"</string>
   <string name="screen_media_picker_error_failed_selection">"Αποτυχία επιλογής πολυμέσου, δοκίμασε ξανά."</string>
   <string name="screen_media_upload_preview_error_failed_processing">"Αποτυχία μεταφόρτωσης μέσου, δοκίμασε ξανά."</string>
   <string name="screen_media_upload_preview_error_failed_sending">"Αποτυχία μεταφόρτωσης πολυμέσων, δοκίμασε ξανά."</string>

libraries/ui-strings/src/main/res/values-et/translations.xml

@@ -273,7 +273,6 @@ Põhjus: %1$s."</string>
   <string name="invite_friends_text">"Hei, suhtle minuga %1$s võrgus: %2$s"</string>
   <string name="login_initial_device_name_android">"%1$s Android"</string>
   <string name="preference_rageshake">"Veast teatamiseks raputa nutiseadet ägedalt"</string>
-  <string name="screen_create_account_title">"Loo kasutajakonto"</string>
   <string name="screen_media_picker_error_failed_selection">"Meediafaili valimine ei õnnestunud. Palun proovi uuesti."</string>
   <string name="screen_media_upload_preview_error_failed_processing">"Meediafaili töötlemine enne üleslaadimist ei õnnestunud. Palun proovi uuesti."</string>
   <string name="screen_media_upload_preview_error_failed_sending">"Meediafaili üleslaadimine ei õnnestunud. Palun proovi uuesti."</string>

libraries/ui-strings/src/main/res/values/localazy.xml

@@ -273,7 +273,6 @@ Reason: %1$s."</string>
   <string name="invite_friends_text">"Hey, talk to me on %1$s: %2$s"</string>
   <string name="login_initial_device_name_android">"%1$s Android"</string>
   <string name="preference_rageshake">"Rageshake to report bug"</string>
-  <string name="screen_create_account_title">"Create account"</string>
   <string name="screen_media_picker_error_failed_selection">"Failed selecting media, please try again."</string>
   <string name="screen_media_upload_preview_error_failed_processing">"Failed processing media to upload, please try again."</string>
   <string name="screen_media_upload_preview_error_failed_sending">"Failed uploading media, please try again."</string>

tools/localazy/config.json

@@ -127,6 +127,7 @@
         "screen_server_confirmation_.*",
         "screen_change_server_.*",
         "screen_change_account_provider_.*",
+        "screen_create_account_.*",
         "screen_account_provider_.*",
         "screen_waitlist_.*",
         "screen_qr_code_login_.*"