Add UI to add a JMAP account to the app

app/core/src/main/java/com/fsck/k9/KoinModule.kt

@@ -25,4 +25,5 @@ val mainModule = module {
     single<TrustedSocketFactory> { DefaultTrustedSocketFactory(get(), get()) }
     single { Clock.INSTANCE }
     factory { ServerNameSuggester() }
+    factory { EmailAddressValidator() }
 }

app/k9mail-jmap/build.gradle

@@ -1,6 +1,7 @@
 apply plugin: 'com.android.application'
 apply plugin: 'org.jetbrains.kotlin.android'
 apply plugin: 'org.jetbrains.kotlin.android.extensions'
+apply plugin: 'kotlin-kapt'
 apply plugin: 'org.jlleitschuh.gradle.ktlint'
 
 if (rootProject.testCoverage) {
@@ -21,6 +22,11 @@ dependencies {
 
     implementation "androidx.appcompat:appcompat:${versions.androidxAppCompat}"
     implementation "com.jakewharton.timber:timber:${versions.timber}"
+    implementation "androidx.constraintlayout:constraintlayout:${versions.androidxConstraintLayout}"
+    implementation "com.google.android.material:material:${versions.materialComponents}"
+    implementation "androidx.navigation:navigation-fragment-ktx:${versions.androidxNavigation}"
+    implementation "androidx.navigation:navigation-ui-ktx:${versions.androidxNavigation}"
+    implementation "androidx.lifecycle:lifecycle-viewmodel-ktx:2.1.0"
 
     testImplementation "org.robolectric:robolectric:${versions.robolectric}"
     testImplementation "junit:junit:${versions.junit}"
@@ -105,6 +111,10 @@ android {
         jvmTarget = kotlinJvmVersion
     }
 
+    dataBinding {
+        enabled = true
+    }
+
     testOptions {
         unitTests {
             includeAndroidResources = true

app/k9mail-jmap/src/main/AndroidManifest.xml

@@ -242,6 +242,10 @@
             android:name="com.fsck.k9.ui.settings.account.AccountSettingsActivity"
             android:label="@string/account_settings_title_fmt" />
 
+        <activity
+            android:name="com.fsck.k9.ui.addaccount.AddAccountActivity"
+            android:label="@string/add_account_action" />
+
         <receiver
             android:name="com.fsck.k9.service.BootReceiver"
             android:enabled="true">

app/k9mail-jmap/src/main/java/com/fsck/k9/Dependencies.kt

@@ -9,6 +9,7 @@ import com.fsck.k9.preferences.K9StoragePersister
 import com.fsck.k9.preferences.StoragePersister
 import com.fsck.k9.resources.resourcesModule
 import com.fsck.k9.storage.storageModule
+import com.fsck.k9.ui.addaccount.uiAddAccountModule
 import org.koin.core.qualifier.named
 import org.koin.dsl.module
 
@@ -25,5 +26,6 @@ val appModules = listOf(
         notificationModule,
         resourcesModule,
         backendsModule,
-        storageModule
+        storageModule,
+        uiAddAccountModule
 )

app/k9mail-jmap/src/main/java/com/fsck/k9/backends/JmapAccountCreator.kt

@@ -0,0 +1,60 @@
+package com.fsck.k9.backends
+
+import com.fsck.k9.Account
+import com.fsck.k9.Preferences
+import com.fsck.k9.account.AccountCreator
+import com.fsck.k9.backend.BackendManager
+import com.fsck.k9.backend.jmap.JmapDiscoveryResult.JmapAccount
+import com.fsck.k9.mail.AuthType
+import com.fsck.k9.mail.ConnectionSecurity
+import com.fsck.k9.mail.ServerSettings
+import com.fsck.k9.mailstore.LocalStoreProvider
+
+class JmapAccountCreator(
+    private val preferences: Preferences,
+    private val backendManager: BackendManager,
+    private val accountCreator: AccountCreator,
+    private val localStoreProvider: LocalStoreProvider
+) {
+    fun createAccount(emailAddress: String, password: String, jmapAccount: JmapAccount) {
+        val serverSettings = createServerSettings(emailAddress, password, jmapAccount)
+
+        val account = preferences.newAccount().apply {
+            email = emailAddress
+            description = jmapAccount.name
+            storeUri = backendManager.createStoreUri(serverSettings)
+            transportUri = backendManager.createTransportUri(serverSettings)
+
+            chipColor = accountCreator.pickColor()
+            deletePolicy = Account.DeletePolicy.ON_DELETE
+        }
+        preferences.saveAccount(account)
+
+        createOutboxFolder(account)
+        fetchFolderList(account)
+    }
+
+    private fun createServerSettings(emailAddress: String, password: String, jmapAccount: JmapAccount): ServerSettings {
+        return ServerSettings(
+            "jmap",
+            null,
+            433,
+            ConnectionSecurity.SSL_TLS_REQUIRED,
+            AuthType.PLAIN,
+            emailAddress,
+            password,
+            null,
+            mapOf("accountId" to jmapAccount.accountId)
+        )
+    }
+
+    private fun createOutboxFolder(account: Account) {
+        val localStore = localStoreProvider.getInstance(account)
+        localStore.createLocalFolder(Account.OUTBOX, Account.OUTBOX_NAME)
+    }
+
+    private fun fetchFolderList(account: Account) {
+        val backend = backendManager.getBackend(account)
+        backend.refreshFolderList()
+    }
+}

app/k9mail-jmap/src/main/java/com/fsck/k9/backends/KoinModule.kt

@@ -1,6 +1,7 @@
 package com.fsck.k9.backends
 
 import com.fsck.k9.backend.BackendManager
+import com.fsck.k9.backend.jmap.JmapAccountDiscovery
 import org.koin.dsl.module
 
 val backendsModule = module {
@@ -17,4 +18,6 @@ val backendsModule = module {
     single { Pop3BackendFactory(get(), get()) }
     single { WebDavBackendFactory(get(), get()) }
     single { JmapBackendFactory(get()) }
+    factory { JmapAccountDiscovery() }
+    factory { JmapAccountCreator(get(), get(), get(), get()) }
 }

app/k9mail-jmap/src/main/java/com/fsck/k9/ui/DataBindingAdapters.kt

@@ -0,0 +1,20 @@
+package com.fsck.k9.ui
+
+import android.view.View
+import androidx.databinding.BindingAdapter
+import com.google.android.material.textfield.TextInputLayout
+
+@BindingAdapter("isVisible")
+fun setVisibility(view: View, value: Boolean) {
+    view.visibility = if (value) View.VISIBLE else View.GONE
+}
+
+@BindingAdapter("error")
+fun setError(view: TextInputLayout, value: Int?) {
+    if (value == null) {
+        view.error = null
+    } else {
+        val errorString = view.context.getString(value)
+        view.error = errorString
+    }
+}

app/k9mail-jmap/src/main/java/com/fsck/k9/ui/addaccount/AddAccountActivity.kt

@@ -0,0 +1,31 @@
+package com.fsck.k9.ui.addaccount
+
+import android.os.Bundle
+import androidx.navigation.NavController
+import androidx.navigation.findNavController
+import androidx.navigation.ui.AppBarConfiguration
+import androidx.navigation.ui.setupActionBarWithNavController
+import com.fsck.k9.activity.K9Activity
+import com.fsck.k9.jmap.R
+
+class AddAccountActivity : K9Activity() {
+    private lateinit var navController: NavController
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setLayout(R.layout.activity_add_account)
+
+        initializeActionBar()
+    }
+
+    private fun initializeActionBar() {
+        val appBarConfiguration = AppBarConfiguration(topLevelDestinationIds = setOf(R.id.addJmapAccountScreen))
+
+        navController = findNavController(R.id.nav_host_fragment)
+        setupActionBarWithNavController(navController, appBarConfiguration)
+    }
+
+    override fun onSupportNavigateUp(): Boolean {
+        return navController.navigateUp() || super.onSupportNavigateUp()
+    }
+}

app/k9mail-jmap/src/main/java/com/fsck/k9/ui/addaccount/AddAccountFragment.kt

@@ -0,0 +1,39 @@
+package com.fsck.k9.ui.addaccount
+
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import androidx.fragment.app.Fragment
+import androidx.navigation.fragment.findNavController
+import com.fsck.k9.jmap.R
+import com.fsck.k9.jmap.databinding.FragmentAddAccountBinding
+import com.fsck.k9.ui.observeNotNull
+import org.koin.androidx.viewmodel.ext.android.viewModel
+
+class AddAccountFragment : Fragment() {
+    private val viewModel: AddAccountViewModel by viewModel()
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        viewModel.getActionEvents().observeNotNull(this) { handleActionEvents(it) }
+    }
+
+    override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
+        val binding = FragmentAddAccountBinding.inflate(inflater, container, false)
+        binding.lifecycleOwner = this
+        binding.viewModel = viewModel
+
+        return binding.root
+    }
+
+    private fun handleActionEvents(action: Action) {
+        when (action) {
+            is Action.GoToMessageList -> goToMessageList()
+        }
+    }
+
+    private fun goToMessageList() {
+        findNavController().navigate(R.id.action_addJmapAccountScreen_to_messageListScreen)
+    }
+}

app/k9mail-jmap/src/main/java/com/fsck/k9/ui/addaccount/AddAccountViewModel.kt

@@ -0,0 +1,157 @@
+package com.fsck.k9.ui.addaccount
+
+import androidx.annotation.StringRes
+import androidx.lifecycle.LiveData
+import androidx.lifecycle.MutableLiveData
+import androidx.lifecycle.Transformations
+import androidx.lifecycle.ViewModel
+import androidx.lifecycle.viewModelScope
+import com.fsck.k9.EmailAddressValidator
+import com.fsck.k9.backend.jmap.JmapAccountDiscovery
+import com.fsck.k9.backend.jmap.JmapDiscoveryResult
+import com.fsck.k9.backend.jmap.JmapDiscoveryResult.JmapAccount
+import com.fsck.k9.backends.JmapAccountCreator
+import com.fsck.k9.helper.SingleLiveEvent
+import com.fsck.k9.helper.measureRealtimeMillisWithResult
+import com.fsck.k9.jmap.R
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.GlobalScope
+import kotlinx.coroutines.delay
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.withContext
+
+class AddAccountViewModel(
+    private val emailAddressValidator: EmailAddressValidator,
+    private val jmapAccountDiscovery: JmapAccountDiscovery,
+    private val jmapAccountCreator: JmapAccountCreator
+) : ViewModel() {
+    val emailAddress = MutableLiveData<String>()
+    val emailAddressError = MutableLiveData<Int?>()
+    val password = MutableLiveData<String>()
+    val passwordError = MutableLiveData<Int?>()
+    val setupErrorText: MutableLiveData<Int> = createMutableLiveData(R.string.empty_string)
+    val isInputEnabled: MutableLiveData<Boolean> = createMutableLiveData(true)
+    val isNextButtonEnabled: MutableLiveData<Boolean> = createMutableLiveData(true)
+    val isProgressBarVisible: MutableLiveData<Boolean> = createMutableLiveData(false)
+    private val actionLiveData = SingleLiveEvent<Action>()
+
+    init {
+        Transformations.distinctUntilChanged(emailAddress).observeForever { resetEmailAddressError() }
+        Transformations.distinctUntilChanged(password).observeForever { resetPasswordError() }
+    }
+
+    fun getActionEvents(): LiveData<Action> = actionLiveData
+
+    fun onNextButtonClicked() {
+        discoverServerSettings()
+    }
+
+    private fun discoverServerSettings() {
+        val emailAddress = this.emailAddress.value?.trim() ?: ""
+        val password = this.password.value ?: ""
+
+        if (!emailAddressValidator.isValidAddressOnly(emailAddress)) {
+            displayEmailAddressError(R.string.add_account__email_address_error)
+            return
+        }
+
+        showDiscoveryProgressBar()
+
+        viewModelScope.launch {
+            val (elapsed, discoveryResult) = measureRealtimeMillisWithResult {
+                withContext(Dispatchers.IO) {
+                    jmapAccountDiscovery.discover(emailAddress, password)
+                }
+            }
+
+            if (elapsed < MIN_PROGRESS_DURATION) {
+                delay(MIN_PROGRESS_DURATION - elapsed)
+            }
+
+            if (discoveryResult is JmapAccount) {
+                createAccount(emailAddress, password, discoveryResult)
+            } else {
+                displayDiscoveryError(discoveryResult)
+                hideDiscoveryProgressBar()
+            }
+        }
+    }
+
+    private suspend fun createAccount(emailAddress: String, password: String, jmapAccount: JmapAccount) {
+        GlobalScope.launch(Dispatchers.IO) {
+            jmapAccountCreator.createAccount(emailAddress, password, jmapAccount)
+        }.join()
+
+        sendActionEvent(Action.GoToMessageList)
+    }
+
+    private fun displayDiscoveryError(discoveryResult: JmapDiscoveryResult) {
+        when (discoveryResult) {
+            is JmapDiscoveryResult.GenericFailure -> {
+                displayError(R.string.add_account__generic_failure)
+            }
+            is JmapDiscoveryResult.NoEmailAccountFoundFailure -> {
+                displayError(R.string.add_account__no_email_account_found)
+            }
+            is JmapDiscoveryResult.AuthenticationFailure -> {
+                displayPasswordError(R.string.add_account__password_error)
+            }
+            is JmapDiscoveryResult.EndpointNotFoundFailure -> {
+                displayError(R.string.add_account__jmap_server_not_found)
+            }
+        }
+    }
+
+    @Suppress("SameParameterValue")
+    private fun displayEmailAddressError(@StringRes error: Int) {
+        emailAddressError.value = error
+    }
+
+    private fun resetEmailAddressError() {
+        emailAddressError.value = null
+    }
+
+    @Suppress("SameParameterValue")
+    private fun displayPasswordError(@StringRes error: Int) {
+        passwordError.value = error
+    }
+
+    private fun resetPasswordError() {
+        passwordError.value = null
+    }
+
+    private fun showDiscoveryProgressBar() {
+        isInputEnabled.value = false
+        isProgressBarVisible.value = true
+        isNextButtonEnabled.value = false
+        setupErrorText.value = R.string.empty_string
+    }
+
+    private fun hideDiscoveryProgressBar() {
+        isInputEnabled.value = true
+        isProgressBarVisible.value = false
+        isNextButtonEnabled.value = true
+    }
+
+    private fun displayError(@StringRes error: Int) {
+        setupErrorText.value = error
+    }
+
+    private fun sendActionEvent(action: Action) {
+        actionLiveData.value = action
+    }
+
+    private fun <T> createMutableLiveData(initialValue: T): MutableLiveData<T> {
+        return MutableLiveData<T>().apply {
+            value = initialValue
+        }
+    }
+
+    companion object {
+        private const val MIN_PROGRESS_DURATION = 500
+    }
+}
+
+sealed class Action {
+    object GoToMessageList : Action()
+}

app/k9mail-jmap/src/main/java/com/fsck/k9/ui/addaccount/KoinModule.kt

@@ -0,0 +1,8 @@
+package com.fsck.k9.ui.addaccount
+
+import org.koin.androidx.viewmodel.dsl.viewModel
+import org.koin.dsl.module
+
+val uiAddAccountModule = module {
+    viewModel { AddAccountViewModel(get(), get(), get()) }
+}

app/k9mail-jmap/src/main/res/layout/activity_add_account.xml

@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="utf-8"?>
+<LinearLayout
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent"
+    android:orientation="vertical">
+
+    <include layout="@layout/toolbar" />
+
+    <fragment
+        android:id="@+id/nav_host_fragment"
+        android:name="androidx.navigation.fragment.NavHostFragment"
+        android:layout_width="match_parent"
+        android:layout_height="0dp"
+        android:layout_weight="1"
+        app:defaultNavHost="true"
+        app:navGraph="@navigation/navigation_add_account" />
+
+</LinearLayout>

app/k9mail-jmap/src/main/res/layout/fragment_add_account.xml

@@ -0,0 +1,117 @@
+<?xml version="1.0" encoding="utf-8"?>
+<layout xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto">
+
+    <data>
+        <variable
+            name="viewModel"
+            type="com.fsck.k9.ui.addaccount.AddAccountViewModel" />
+    </data>
+
+    <ScrollView
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:fillViewport="true"
+        android:fitsSystemWindows="true">
+
+        <androidx.constraintlayout.widget.ConstraintLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content">
+
+            <com.google.android.material.textfield.TextInputLayout
+                android:id="@+id/emailAddressLayout"
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_marginStart="16dp"
+                android:layout_marginTop="16dp"
+                android:layout_marginEnd="16dp"
+                app:error="@{viewModel.emailAddressError}"
+                app:errorEnabled="true"
+                app:layout_constraintEnd_toEndOf="parent"
+                app:layout_constraintStart_toStartOf="parent"
+                app:layout_constraintTop_toTopOf="parent">
+
+                <com.google.android.material.textfield.TextInputEditText
+                    android:id="@+id/emailAddress"
+                    android:layout_width="match_parent"
+                    android:layout_height="wrap_content"
+                    android:enabled="@{viewModel.isInputEnabled}"
+                    android:hint="@string/account_setup_basics_email_hint"
+                    android:imeOptions="flagNoExtractUi"
+                    android:inputType="textEmailAddress"
+                    android:text="@={viewModel.emailAddress}" />
+
+            </com.google.android.material.textfield.TextInputLayout>
+
+            <com.google.android.material.textfield.TextInputLayout
+                android:id="@+id/emailPasswordLayout"
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_marginStart="16dp"
+                android:layout_marginTop="8dp"
+                android:layout_marginEnd="16dp"
+                app:error="@{viewModel.passwordError}"
+                app:errorEnabled="true"
+                app:layout_constraintEnd_toEndOf="parent"
+                app:layout_constraintStart_toStartOf="parent"
+                app:layout_constraintTop_toBottomOf="@+id/emailAddressLayout"
+                app:passwordToggleEnabled="true">
+
+                <com.google.android.material.textfield.TextInputEditText
+                    android:id="@+id/emailPassword"
+                    android:layout_width="match_parent"
+                    android:layout_height="wrap_content"
+                    android:enabled="@{viewModel.isInputEnabled}"
+                    android:hint="@string/account_setup_basics_password_hint"
+                    android:imeOptions="flagNoExtractUi"
+                    android:inputType="textPassword"
+                    android:text="@={viewModel.password}" />
+
+            </com.google.android.material.textfield.TextInputLayout>
+
+            <TextView
+                android:id="@+id/setupError"
+                android:layout_width="0dp"
+                android:layout_height="wrap_content"
+                android:layout_marginStart="16dp"
+                android:layout_marginTop="16dp"
+                android:layout_marginEnd="16dp"
+                android:text="@{viewModel.setupErrorText}"
+                app:layout_constraintEnd_toEndOf="parent"
+                app:layout_constraintStart_toStartOf="parent"
+                app:layout_constraintTop_toBottomOf="@+id/emailPasswordLayout" />
+
+            <ProgressBar
+                android:id="@+id/progressBar"
+                style="?android:attr/progressBarStyle"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:layout_marginStart="16dp"
+                android:layout_marginTop="32dp"
+                android:layout_marginEnd="16dp"
+                android:layout_marginBottom="32dp"
+                app:isVisible="@{viewModel.isProgressBarVisible()}"
+                app:layout_constraintBottom_toTopOf="@+id/nextButton"
+                app:layout_constraintEnd_toEndOf="parent"
+                app:layout_constraintStart_toStartOf="parent"
+                app:layout_constraintTop_toBottomOf="@+id/setupError" />
+
+            <Button
+                android:id="@+id/nextButton"
+                style="@style/Widget.AppCompat.Button.Colored"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:layout_marginTop="24dp"
+                android:layout_marginEnd="16dp"
+                android:layout_marginBottom="16dp"
+                android:enabled="@{viewModel.isNextButtonEnabled()}"
+                android:onClick="@{() -> viewModel.onNextButtonClicked()}"
+                android:text="@string/next_action"
+                app:layout_constraintBottom_toBottomOf="parent"
+                app:layout_constraintEnd_toEndOf="parent"
+                app:layout_constraintTop_toBottomOf="@+id/emailPasswordLayout"
+                app:layout_constraintVertical_bias="1.0" />
+
+        </androidx.constraintlayout.widget.ConstraintLayout>
+    </ScrollView>
+</layout>

app/k9mail-jmap/src/main/res/navigation/navigation_add_account.xml

@@ -0,0 +1,25 @@
+<?xml version="1.0" encoding="utf-8"?>
+<navigation xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/navigation_add_account"
+    app:startDestination="@id/addJmapAccountScreen">
+
+    <fragment
+        android:id="@+id/addJmapAccountScreen"
+        android:name="com.fsck.k9.ui.addaccount.AddAccountFragment"
+        android:label="@string/add_account_action"
+        tools:layout="@layout/fragment_add_account">
+
+        <action
+            android:id="@+id/action_addJmapAccountScreen_to_messageListScreen"
+            app:destination="@id/messageListScreen" />
+
+    </fragment>
+
+    <activity
+        android:id="@+id/messageListScreen"
+        android:name="com.fsck.k9.activity.MessageList"
+        tools:layout="@layout/message_list"/>
+
+</navigation>

app/k9mail-jmap/src/main/res/navigation/navigation_onboarding.xml

@@ -0,0 +1,45 @@
+<?xml version="1.0" encoding="utf-8"?>
+<navigation xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
+    xmlns:tools="http://schemas.android.com/tools"
+    android:id="@+id/navigation_onboarding"
+    app:startDestination="@id/welcomeScreen">
+
+    <fragment
+        android:id="@+id/welcomeScreen"
+        android:name="com.fsck.k9.ui.onboarding.WelcomeFragment"
+        android:label="@string/welcome_message_title"
+        tools:layout="@layout/fragment_welcome_message">
+
+        <action
+            android:id="@+id/action_welcomeScreen_to_settingsImportScreen"
+            app:destination="@id/settingsImportScreen" />
+
+        <action
+            android:id="@+id/action_welcomeScreen_to_addAccountScreen"
+            app:destination="@id/addAccountScreen" />
+
+        <action
+            android:id="@+id/action_welcomeScreen_to_messageListScreen"
+            app:destination="@id/messageListScreen" />
+
+    </fragment>
+
+    <fragment
+        android:id="@+id/settingsImportScreen"
+        android:name="com.fsck.k9.ui.settings.import.SettingsImportFragment"
+        android:label="@string/settings_import_title"
+        tools:layout="@layout/fragment_settings_import"/>
+
+    <activity
+        android:id="@+id/addAccountScreen"
+        android:name="com.fsck.k9.ui.addaccount.AddAccountActivity"
+        android:label="@string/add_account_action"
+        tools:layout="@layout/activity_add_account"/>
+
+    <activity
+        android:id="@+id/messageListScreen"
+        android:name="com.fsck.k9.activity.MessageList"
+        tools:layout="@layout/message_list"/>
+
+</navigation>

app/k9mail-jmap/src/main/res/values/strings.xml

@@ -1,4 +1,11 @@
 <?xml version='1.0' encoding='UTF-8'?>
 <resources>
     <string name="app_name">K-9 JMAP</string>
+    <string name="empty_string" translatable="false" />
+
+    <string name="add_account__email_address_error">Please enter a valid email address</string>
+    <string name="add_account__password_error">"Couldn't sign in. Please make sure your password is correct."</string>
+    <string name="add_account__generic_failure">Unknown error while discovering server settings</string>
+    <string name="add_account__no_email_account_found">"Couldn't find an email account on the JMAP server"</string>
+    <string name="add_account__jmap_server_not_found">"Couldn't find the JMAP server from your email address"</string>
 </resources>

backend/jmap/src/main/java/com/fsck/k9/backend/jmap/JmapAccountDiscovery.kt

@@ -0,0 +1,46 @@
+package com.fsck.k9.backend.jmap
+
+import java.net.UnknownHostException
+import rs.ltt.jmap.client.JmapClient
+import rs.ltt.jmap.client.api.EndpointNotFoundException
+import rs.ltt.jmap.client.api.UnauthorizedException
+import rs.ltt.jmap.common.entity.capability.MailAccountCapability
+import timber.log.Timber
+
+class JmapAccountDiscovery {
+    fun discover(emailAddress: String, password: String): JmapDiscoveryResult {
+        val jmapClient = JmapClient(emailAddress, password)
+        val session = try {
+            jmapClient.session.futureGetOrThrow()
+        } catch (e: EndpointNotFoundException) {
+            return JmapDiscoveryResult.EndpointNotFoundFailure
+        } catch (e: UnknownHostException) {
+            return JmapDiscoveryResult.EndpointNotFoundFailure
+        } catch (e: UnauthorizedException) {
+            return JmapDiscoveryResult.AuthenticationFailure
+        } catch (e: Exception) {
+            Timber.e(e, "Unable to get JMAP session")
+            return JmapDiscoveryResult.GenericFailure(e)
+        }
+
+        val accounts = session.getAccounts(MailAccountCapability::class.java)
+        val accountId = when {
+            accounts.isEmpty() -> return JmapDiscoveryResult.NoEmailAccountFoundFailure
+            accounts.size == 1 -> accounts.keys.first()
+            else -> session.getPrimaryAccount(MailAccountCapability::class.java)
+        }
+
+        val account = accounts[accountId]!!
+        val accountName = account.name ?: emailAddress
+        return JmapDiscoveryResult.JmapAccount(accountId, accountName)
+    }
+}
+
+sealed class JmapDiscoveryResult {
+    class GenericFailure(val cause: Throwable) : JmapDiscoveryResult()
+    object EndpointNotFoundFailure : JmapDiscoveryResult()
+    object AuthenticationFailure : JmapDiscoveryResult()
+    object NoEmailAccountFoundFailure : JmapDiscoveryResult()
+
+    data class JmapAccount(val accountId: String, val name: String) : JmapDiscoveryResult()
+}

backend/jmap/src/main/java/com/fsck/k9/backend/jmap/JmapExtensions.kt

@@ -7,13 +7,17 @@ import rs.ltt.jmap.client.MethodResponses
 import rs.ltt.jmap.common.method.MethodResponse
 
 internal inline fun <reified T : MethodResponse> ListenableFuture<MethodResponses>.getMainResponseBlocking(): T {
-    return try {
-        get().getMain(T::class.java)
-    } catch (e: ExecutionException) {
-        throw e.cause ?: e
-    }
+    return futureGetOrThrow().getMain(T::class.java)
 }
 
 internal inline fun <reified T : MethodResponse> JmapRequest.Call.getMainResponseBlocking(): T {
     return methodResponses.getMainResponseBlocking()
 }
+
+internal inline fun <T> ListenableFuture<T>.futureGetOrThrow(): T {
+    return try {
+        get()
+    } catch (e: ExecutionException) {
+        throw e.cause ?: e
+    }
+}

build.gradle

@@ -12,7 +12,7 @@ buildscript {
                 'kotlin': '1.3.50',
                 'androidxAppCompat': '1.0.2',
                 'androidxRecyclerView': '1.0.0',
-                'androidxLifecycleExtensions': '2.0.0',
+                'androidxLifecycleExtensions': '2.1.0',
                 'androidxAnnotation': '1.0.1',
                 'androidxNavigation': '2.0.0',
                 'androidxConstraintLayout': '1.1.3',