feat(authenticator): Add Select Auth Factor and Confirm Password UIs

authenticator/src/main/java/com/amplifyframework/ui/authenticator/AuthenticatorStepState.kt

@@ -24,6 +24,7 @@ import com.amplifyframework.auth.AuthUserAttribute
 import com.amplifyframework.auth.MFAType
 import com.amplifyframework.auth.result.AuthSignOutResult
 import com.amplifyframework.auth.result.AuthWebAuthnCredential
+import com.amplifyframework.ui.authenticator.enums.AuthFactor
 import com.amplifyframework.ui.authenticator.enums.AuthenticatorInitialStep
 import com.amplifyframework.ui.authenticator.enums.AuthenticatorStep
 import com.amplifyframework.ui.authenticator.forms.MutableFormState
@@ -94,6 +95,68 @@ interface SignInState : AuthenticatorStepState {
     suspend fun signIn()
 }
 
+/**
+ * The user has entered their username and must select the authentication factor they'd like to use to sign in
+ */
+@Stable
+interface SignInSelectAuthFactorState : AuthenticatorStepState {
+    /**
+     * The input form state holder for this step.
+     */
+    val form: MutableFormState
+
+    /**
+     * The username entered in the SignIn step
+     */
+    val username: String
+
+    /**
+     * The available types to select how to sign in.
+     */
+    val availableAuthFactors: Set<AuthFactor>
+
+    /**
+     * The factor the user selected and is currently being processed
+     */
+    val selectedFactor: AuthFactor?
+
+    /**
+     * Move the user to a different [AuthenticatorInitialStep].
+     */
+    fun moveTo(step: AuthenticatorInitialStep)
+
+    /**
+     * Initiate a sign in with one of the available sign in types
+     */
+    suspend fun select(authFactor: AuthFactor)
+}
+
+/**
+ * A user has entered their username and must enter their password to continue signing in
+ */
+@Stable
+interface SignInConfirmPasswordState : AuthenticatorStepState {
+    /**
+     * The input form state holder for this step.
+     */
+    val form: MutableFormState
+
+    /**
+     * The username entered in the SignIn step
+     */
+    val username: String
+
+    /**
+     * Move the user to a different [AuthenticatorInitialStep].
+     */
+    fun moveTo(step: AuthenticatorInitialStep)
+
+    /**
+     * Initiate a sign in with the information entered into the [form].
+     */
+    suspend fun signIn()
+}
+
 /**
  * The user has completed the initial Sign In step, and needs to enter the confirmation code from an MFA
  * message to complete the sign in process.

authenticator/src/main/java/com/amplifyframework/ui/authenticator/data/AuthFactor.kt

@@ -0,0 +1,53 @@
+/*
+ * Copyright 2025 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License").
+ * You may not use this file except in compliance with the License.
+ * A copy of the License is located at
+ *
+ *  http://aws.amazon.com/apache2.0
+ *
+ * or in the "license" file accompanying this file. This file is distributed
+ * on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ * express or implied. See the License for the specific language governing
+ * permissions and limitations under the License.
+ */
+
+package com.amplifyframework.ui.authenticator.enums
+
+import com.amplifyframework.auth.AuthFactorType
+
+sealed interface AuthFactor {
+    data class Password(val srp: Boolean = true) : AuthFactor
+    data object EmailOtp : AuthFactor
+    data object SmsOtp : AuthFactor
+    data object WebAuthn : AuthFactor
+}
+
+internal fun AuthFactor.toAuthFactorType() = when (this) {
+    AuthFactor.EmailOtp -> AuthFactorType.EMAIL_OTP
+    AuthFactor.SmsOtp -> AuthFactorType.SMS_OTP
+    AuthFactor.WebAuthn -> AuthFactorType.WEB_AUTHN
+    is AuthFactor.Password -> if (srp) AuthFactorType.PASSWORD_SRP else AuthFactorType.PASSWORD
+}
+
+internal fun AuthFactorType.toAuthFactor() = when (this) {
+    AuthFactorType.PASSWORD -> AuthFactor.Password(srp = false)
+    AuthFactorType.PASSWORD_SRP -> AuthFactor.Password(srp = true)
+    AuthFactorType.EMAIL_OTP -> AuthFactor.EmailOtp
+    AuthFactorType.SMS_OTP -> AuthFactor.SmsOtp
+    AuthFactorType.WEB_AUTHN -> AuthFactor.WebAuthn
+}
+
+internal val AuthFactor.challengeResponse: String
+    get() = this.toAuthFactorType().challengeResponse
+
+internal fun Collection<AuthFactorType>.toAuthFactors(): Set<AuthFactor> {
+    // If both SRP and password are available then use SRP to sign in
+    var factors = this
+    if (this.contains(AuthFactorType.PASSWORD) && this.contains(AuthFactorType.PASSWORD_SRP)) {
+        factors = this - AuthFactorType.PASSWORD // remove password
+    }
+    return factors.map { it.toAuthFactor() }.toSet()
+}
+internal fun Collection<AuthFactor>.containsPassword() = any { it is AuthFactor.Password }

authenticator/src/main/java/com/amplifyframework/ui/authenticator/enums/AuthenticatorStep.kt

@@ -46,6 +46,16 @@ abstract class AuthenticatorStep internal constructor() {
      */
     object SignIn : AuthenticatorInitialStep()
 
+    /**
+     * The user has entered their username and must select the authentication factor they'd like to use to sign in
+     */
+    object SignInSelectAuthFactor : AuthenticatorStep()
+
+    /**
+     * A user has entered their username and must enter their password to continue signing in
+     */
+    object SignInConfirmPassword : AuthenticatorStep()
+
     /**
      * The user has completed the initial Sign In step, and needs to enter the confirmation code from a custom
      * challenge to complete the sign in process.

authenticator/src/main/java/com/amplifyframework/ui/authenticator/states/SignInConfirmPasswordStateImpl.kt

@@ -0,0 +1,33 @@
+package com.amplifyframework.ui.authenticator.states
+
+import com.amplifyframework.ui.authenticator.SignInConfirmPasswordState
+import com.amplifyframework.ui.authenticator.auth.SignInMethod
+import com.amplifyframework.ui.authenticator.enums.AuthenticatorInitialStep
+import com.amplifyframework.ui.authenticator.enums.AuthenticatorStep
+import com.amplifyframework.ui.authenticator.forms.FieldKey
+
+internal class SignInConfirmPasswordStateImpl(
+    override val username: String,
+    val signInMethod: SignInMethod,
+    private val onSubmit: suspend (password: String) -> Unit,
+    private val onMoveTo: (step: AuthenticatorInitialStep) -> Unit
+) : BaseStateImpl(),
+    SignInConfirmPasswordState {
+
+    init {
+        form.addFields {
+            password()
+        }
+    }
+
+    override val step: AuthenticatorStep = AuthenticatorStep.SignInConfirmPassword
+    override fun moveTo(step: AuthenticatorInitialStep) = onMoveTo(step)
+
+    override suspend fun signIn() = doSubmit {
+        val password = form.getTrimmed(FieldKey.Password)!!
+        onSubmit(password)
+    }
+}
+
+internal val SignInConfirmPasswordState.signInMethod: SignInMethod
+    get() = (this as SignInConfirmPasswordStateImpl).signInMethod

authenticator/src/main/java/com/amplifyframework/ui/authenticator/states/SignInSelectAuthFactorStateImpl.kt

@@ -0,0 +1,49 @@
+package com.amplifyframework.ui.authenticator.states
+
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.setValue
+import com.amplifyframework.ui.authenticator.SignInSelectAuthFactorState
+import com.amplifyframework.ui.authenticator.auth.SignInMethod
+import com.amplifyframework.ui.authenticator.enums.AuthFactor
+import com.amplifyframework.ui.authenticator.enums.AuthenticatorInitialStep
+import com.amplifyframework.ui.authenticator.enums.AuthenticatorStep
+import com.amplifyframework.ui.authenticator.enums.containsPassword
+
+internal class SignInSelectAuthFactorStateImpl(
+    override val username: String,
+    val signInMethod: SignInMethod,
+    override val availableAuthFactors: Set<AuthFactor>,
+    private val onSubmit: suspend (authFactor: AuthFactor) -> Unit,
+    private val onMoveTo: (step: AuthenticatorInitialStep) -> Unit
+) : BaseStateImpl(),
+    SignInSelectAuthFactorState {
+    override val step: AuthenticatorStep = AuthenticatorStep.SignInSelectAuthFactor
+
+    override var selectedFactor: AuthFactor? by mutableStateOf(null)
+
+    init {
+        if (availableAuthFactors.containsPassword()) {
+            form.addFields { password() }
+        }
+    }
+
+    override fun moveTo(step: AuthenticatorInitialStep) = onMoveTo(step)
+
+    override suspend fun select(authFactor: AuthFactor) {
+        // Clear errors
+        form.fields.values.forEach { it.state.error = null }
+
+        selectedFactor = authFactor
+        form.enabled = false
+        onSubmit(authFactor)
+        form.enabled = true
+        selectedFactor = null
+    }
+}
+
+internal fun SignInSelectAuthFactorState.getPasswordFactor(): AuthFactor =
+    availableAuthFactors.first { it is AuthFactor.Password }
+
+internal val SignInSelectAuthFactorState.signInMethod: SignInMethod
+    get() = (this as SignInSelectAuthFactorStateImpl).signInMethod