refactor: shared device-credential prompt for key access

rememberDeviceAuthenticator (commonsUI) replaces the app's authenticate()
helper: Android keeps BiometricPrompt with the keyguard fallback in its
actual; desktop and iOS approve at once for now, as Android does on a
device without a screen lock. UpdateZapAmountDialog no longer carries the
prompt code, and AccountBackupScreen asks through the port. commonsUI's
Android source set takes androidx.biometric (Apache-2.0, already shipped).

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01S7FuNBSKiyVecARSoE4B9P

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/note/UpdateZapAmountDialog.kt

@@ -20,14 +20,6 @@
  */
 package com.vitorpamplona.amethyst.ui.note
 
-import android.app.KeyguardManager
-import android.content.Context
-import android.content.Intent
-import android.os.Build
-import androidx.activity.compose.ManagedActivityResultLauncher
-import androidx.activity.result.ActivityResult
-import androidx.biometric.BiometricManager
-import androidx.biometric.BiometricPrompt
 import androidx.compose.animation.animateContentSize
 import androidx.compose.animation.core.Spring
 import androidx.compose.animation.core.spring
@@ -59,7 +51,6 @@ import androidx.compose.material3.Surface
 import androidx.compose.material3.Switch
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
-import androidx.compose.runtime.Immutable
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.key
 import androidx.compose.runtime.mutableStateMapOf
@@ -86,10 +77,6 @@ import com.vitorpamplona.amethyst.commons.icons.symbols.Icon
 import com.vitorpamplona.amethyst.commons.icons.symbols.MaterialSymbols
 import com.vitorpamplona.amethyst.commons.resources.Res
 import com.vitorpamplona.amethyst.commons.resources.add
-import com.vitorpamplona.amethyst.commons.resources.app_name
-import com.vitorpamplona.amethyst.commons.resources.biometric_authentication_failed
-import com.vitorpamplona.amethyst.commons.resources.biometric_authentication_failed_explainer
-import com.vitorpamplona.amethyst.commons.resources.biometric_authentication_failed_explainer_with_error
 import com.vitorpamplona.amethyst.commons.resources.new_amount_in_sats
 import com.vitorpamplona.amethyst.commons.resources.quick_zap_amounts
 import com.vitorpamplona.amethyst.commons.resources.quick_zap_amounts_explainer
@@ -121,10 +108,8 @@ import com.vitorpamplona.amethyst.commons.ui.theme.placeholderText
 import com.vitorpamplona.amethyst.commons.util.showAmount
 import com.vitorpamplona.amethyst.commons.viewmodels.AccountViewModel
 import com.vitorpamplona.amethyst.commons.viewmodels.mockAccountViewModel
-import com.vitorpamplona.amethyst.ui.screen.loggedIn.keyBackup.getFragmentActivity
 import com.vitorpamplona.quartz.nip57Zaps.ZapReceiptEvent
 import kotlinx.collections.immutable.toImmutableList
-import kotlinx.coroutines.launch
 
 @OptIn(ExperimentalLayoutApi::class)
 @Composable
@@ -449,118 +434,3 @@ private fun ZapAmountPresetChip(
         }
     }
 }
-
-/**
- * Labels the device-credential and biometric prompts need. Resolved in
- * composition and passed down because [authenticate] runs from an onClick
- * lambda and from Android's own biometric callbacks, neither of which can
- * reach a Compose resource.
- */
-@Immutable
-data class AuthPromptLabels(
-    val appName: String,
-    val failedTitle: String,
-    val failedExplainer: String,
-    val failedExplainerWithError: String,
-)
-
-@Composable
-fun rememberAuthPromptLabels(): AuthPromptLabels =
-    AuthPromptLabels(
-        appName = stringRes(Res.string.app_name),
-        failedTitle = stringRes(Res.string.biometric_authentication_failed),
-        failedExplainer = stringRes(Res.string.biometric_authentication_failed_explainer),
-        failedExplainerWithError = stringRes(Res.string.biometric_authentication_failed_explainer_with_error),
-    )
-
-fun authenticate(
-    title: String,
-    context: Context,
-    labels: AuthPromptLabels,
-    keyguardLauncher: ManagedActivityResultLauncher<Intent, ActivityResult>,
-    onApproved: () -> Unit,
-    onError: (String, String) -> Unit,
-) {
-    val fragmentContext = context.getFragmentActivity()!!
-    val keyguardManager =
-        fragmentContext.getSystemService(Context.KEYGUARD_SERVICE) as KeyguardManager
-
-    if (!keyguardManager.isDeviceSecure) {
-        onApproved()
-        return
-    }
-
-    @Suppress("DEPRECATION")
-    fun keyguardPrompt() {
-        val intent =
-            keyguardManager.createConfirmDeviceCredentialIntent(
-                labels.appName,
-                title,
-            )
-
-        keyguardLauncher.launch(intent)
-    }
-
-    if (Build.VERSION.SDK_INT <= Build.VERSION_CODES.Q) {
-        keyguardPrompt()
-        return
-    }
-
-    val biometricManager = BiometricManager.from(context)
-    val authenticators =
-        BiometricManager.Authenticators.BIOMETRIC_STRONG or
-            BiometricManager.Authenticators.DEVICE_CREDENTIAL
-
-    val promptInfo =
-        BiometricPrompt.PromptInfo
-            .Builder()
-            .setTitle(labels.appName)
-            .setSubtitle(title)
-            .setAllowedAuthenticators(authenticators)
-            .build()
-
-    val biometricPrompt =
-        BiometricPrompt(
-            fragmentContext,
-            object : BiometricPrompt.AuthenticationCallback() {
-                override fun onAuthenticationError(
-                    errorCode: Int,
-                    errString: CharSequence,
-                ) {
-                    super.onAuthenticationError(errorCode, errString)
-
-                    when (errorCode) {
-                        BiometricPrompt.ERROR_NEGATIVE_BUTTON -> {
-                            keyguardPrompt()
-                        }
-
-                        BiometricPrompt.ERROR_LOCKOUT -> {
-                            keyguardPrompt()
-                        }
-
-                        else -> {
-                            onError(
-                                labels.failedTitle,
-                                labels.failedExplainerWithError.format(errString.toString()),
-                            )
-                        }
-                    }
-                }
-
-                override fun onAuthenticationFailed() {
-                    super.onAuthenticationFailed()
-                    onError(labels.failedTitle, labels.failedExplainer)
-                }
-
-                override fun onAuthenticationSucceeded(result: BiometricPrompt.AuthenticationResult) {
-                    super.onAuthenticationSucceeded(result)
-                    onApproved()
-                }
-            },
-        )
-
-    when (biometricManager.canAuthenticate(authenticators)) {
-        BiometricManager.BIOMETRIC_SUCCESS -> biometricPrompt.authenticate(promptInfo)
-        else -> keyguardPrompt()
-    }
-}

amethyst/src/main/java/com/vitorpamplona/amethyst/ui/screen/loggedIn/keyBackup/AccountBackupScreen.kt

@@ -20,16 +20,12 @@
  */
 package com.vitorpamplona.amethyst.ui.screen.loggedIn.keyBackup
 
-import android.app.Activity
 import android.content.ClipData
 import android.content.Context
 import android.content.ContextWrapper
 import android.os.PersistableBundle
 import android.view.WindowManager
 import android.widget.Toast
-import androidx.activity.compose.rememberLauncherForActivityResult
-import androidx.activity.result.ActivityResult
-import androidx.activity.result.contract.ActivityResultContracts
 import androidx.compose.animation.AnimatedVisibility
 import androidx.compose.foundation.background
 import androidx.compose.foundation.clickable
@@ -136,14 +132,13 @@ import com.vitorpamplona.amethyst.commons.ui.navigation.navs.EmptyNav
 import com.vitorpamplona.amethyst.commons.ui.navigation.navs.INav
 import com.vitorpamplona.amethyst.commons.ui.navigation.topbars.TopBarWithBackButton
 import com.vitorpamplona.amethyst.commons.ui.pluralStringRes
+import com.vitorpamplona.amethyst.commons.ui.privacylock.rememberDeviceAuthenticator
 import com.vitorpamplona.amethyst.commons.ui.screen.loggedIn.qrcode.BackButton
 import com.vitorpamplona.amethyst.commons.ui.screen.loggedIn.qrcode.QrCodeDrawer
 import com.vitorpamplona.amethyst.commons.ui.stringRes
 import com.vitorpamplona.amethyst.commons.ui.theme.ThemeComparisonRow
 import com.vitorpamplona.amethyst.commons.viewmodels.AccountViewModel
 import com.vitorpamplona.amethyst.commons.viewmodels.mockAccountViewModel
-import com.vitorpamplona.amethyst.ui.note.authenticate
-import com.vitorpamplona.amethyst.ui.note.rememberAuthPromptLabels
 import com.vitorpamplona.quartz.nip19Bech32.toNsec
 import com.vitorpamplona.quartz.nip49PrivKeyEnc.Nip49
 import kotlinx.coroutines.CoroutineScope
@@ -701,13 +696,6 @@ private class KeyAccessGate {
     var isUnlocked by mutableStateOf(false)
         private set
 
-    /**
-     * The action waiting on the keyguard fallback activity to return. Only a new request or
-     * that activity's result replaces it: the activity stops this screen (so ON_STOP must not
-     * clear it), and a wrong fingerprint before the lockout fallback is not a final failure.
-     */
-    var pending: (() -> Unit)? = null
-
     var prompt: ((onApproved: () -> Unit) -> Unit)? = null
 
     fun withAccess(action: () -> Unit) {
@@ -728,32 +716,15 @@ private class KeyAccessGate {
 
 @Composable
 private fun rememberKeyAccessGate(accountViewModel: AccountViewModel): KeyAccessGate {
-    val context = LocalContext.current
+    val authenticator = rememberDeviceAuthenticator()
-    val authLabels = rememberAuthPromptLabels()
     val authTitle = stringRes(Res.string.backup_keys)
     val gate = remember { KeyAccessGate() }
 
-    val keyguardLauncher =
-        rememberLauncherForActivityResult(ActivityResultContracts.StartActivityForResult()) { result: ActivityResult ->
-            val action = gate.pending
-            gate.pending = null
-            if (result.resultCode == Activity.RESULT_OK) {
-                action?.invoke()
-            }
-        }
-
     SideEffect {
         gate.prompt = { onApproved ->
-            gate.pending = onApproved
+            authenticator.authenticate(
-            authenticate(
                 title = authTitle,
-                context = context,
+                onApproved = onApproved,
-                labels = authLabels,
-                keyguardLauncher = keyguardLauncher,
-                onApproved = {
-                    gate.pending = null
-                    onApproved()
-                },
                 onError = { title, message -> accountViewModel.toastManager.toast(title, message) },
             )
         }

commonsUI/build.gradle.kts

@@ -216,6 +216,8 @@ kotlin {
                 implementation(libs.androidx.activity.compose)
                 // Camera permission prompt for TakePicture. Apache-2.0, already in the app.
                 implementation(libs.accompanist.permissions)
+                // BiometricPrompt behind rememberDeviceAuthenticator. Apache-2.0, already in the app.
+                implementation(libs.androidx.biometric.ktx)
             }
         }
 

commonsUI/src/androidMain/kotlin/com/vitorpamplona/amethyst/commons/ui/privacylock/DeviceAuthenticator.android.kt

@@ -0,0 +1,207 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.ui.privacylock
+
+import android.app.Activity
+import android.app.KeyguardManager
+import android.content.Context
+import android.content.ContextWrapper
+import android.content.Intent
+import android.os.Build
+import androidx.activity.compose.ManagedActivityResultLauncher
+import androidx.activity.compose.rememberLauncherForActivityResult
+import androidx.activity.result.ActivityResult
+import androidx.activity.result.contract.ActivityResultContracts
+import androidx.biometric.BiometricManager
+import androidx.biometric.BiometricPrompt
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.Immutable
+import androidx.compose.runtime.remember
+import androidx.compose.ui.platform.LocalContext
+import androidx.fragment.app.FragmentActivity
+import com.vitorpamplona.amethyst.commons.resources.Res
+import com.vitorpamplona.amethyst.commons.resources.app_name
+import com.vitorpamplona.amethyst.commons.resources.biometric_authentication_failed
+import com.vitorpamplona.amethyst.commons.resources.biometric_authentication_failed_explainer
+import com.vitorpamplona.amethyst.commons.resources.biometric_authentication_failed_explainer_with_error
+import com.vitorpamplona.amethyst.commons.ui.stringRes
+
+/** The action waiting on the keyguard activity, which only its result may run or replace. */
+private class PendingApproval {
+    var action: (() -> Unit)? = null
+}
+
+@Composable
+actual fun rememberDeviceAuthenticator(): DeviceAuthenticator {
+    val context = LocalContext.current
+    val labels = rememberAuthPromptLabels()
+    val pending = remember { PendingApproval() }
+
+    val keyguardLauncher =
+        rememberLauncherForActivityResult(ActivityResultContracts.StartActivityForResult()) { result: ActivityResult ->
+            val action = pending.action
+            pending.action = null
+            if (result.resultCode == Activity.RESULT_OK) {
+                action?.invoke()
+            }
+        }
+
+    return remember(context, labels, keyguardLauncher) {
+        DeviceAuthenticator { title, onApproved, onError ->
+            pending.action = onApproved
+            authenticate(
+                title = title,
+                context = context,
+                labels = labels,
+                keyguardLauncher = keyguardLauncher,
+                onApproved = {
+                    pending.action = null
+                    onApproved()
+                },
+                onError = onError,
+            )
+        }
+    }
+}
+
+private fun Context.findFragmentActivity(): FragmentActivity? {
+    var current: Context = this
+    while (current is ContextWrapper) {
+        if (current is FragmentActivity) return current
+        current = current.baseContext
+    }
+    return null
+}
+
+/**
+ * Labels the device-credential and biometric prompts need. Resolved in
+ * composition and passed down because [authenticate] runs from an onClick
+ * lambda and from Android's own biometric callbacks, neither of which can
+ * reach a Compose resource.
+ */
+@Immutable
+private data class AuthPromptLabels(
+    val appName: String,
+    val failedTitle: String,
+    val failedExplainer: String,
+    val failedExplainerWithError: String,
+)
+
+@Composable
+private fun rememberAuthPromptLabels(): AuthPromptLabels =
+    AuthPromptLabels(
+        appName = stringRes(Res.string.app_name),
+        failedTitle = stringRes(Res.string.biometric_authentication_failed),
+        failedExplainer = stringRes(Res.string.biometric_authentication_failed_explainer),
+        failedExplainerWithError = stringRes(Res.string.biometric_authentication_failed_explainer_with_error),
+    )
+
+private fun authenticate(
+    title: String,
+    context: Context,
+    labels: AuthPromptLabels,
+    keyguardLauncher: ManagedActivityResultLauncher<Intent, ActivityResult>,
+    onApproved: () -> Unit,
+    onError: (String, String) -> Unit,
+) {
+    val fragmentContext = context.findFragmentActivity() ?: return onApproved()
+    val keyguardManager =
+        fragmentContext.getSystemService(Context.KEYGUARD_SERVICE) as KeyguardManager
+
+    if (!keyguardManager.isDeviceSecure) {
+        onApproved()
+        return
+    }
+
+    @Suppress("DEPRECATION")
+    fun keyguardPrompt() {
+        val intent =
+            keyguardManager.createConfirmDeviceCredentialIntent(
+                labels.appName,
+                title,
+            )
+
+        keyguardLauncher.launch(intent)
+    }
+
+    if (Build.VERSION.SDK_INT <= Build.VERSION_CODES.Q) {
+        keyguardPrompt()
+        return
+    }
+
+    val biometricManager = BiometricManager.from(context)
+    val authenticators =
+        BiometricManager.Authenticators.BIOMETRIC_STRONG or
+            BiometricManager.Authenticators.DEVICE_CREDENTIAL
+
+    val promptInfo =
+        BiometricPrompt.PromptInfo
+            .Builder()
+            .setTitle(labels.appName)
+            .setSubtitle(title)
+            .setAllowedAuthenticators(authenticators)
+            .build()
+
+    val biometricPrompt =
+        BiometricPrompt(
+            fragmentContext,
+            object : BiometricPrompt.AuthenticationCallback() {
+                override fun onAuthenticationError(
+                    errorCode: Int,
+                    errString: CharSequence,
+                ) {
+                    super.onAuthenticationError(errorCode, errString)
+
+                    when (errorCode) {
+                        BiometricPrompt.ERROR_NEGATIVE_BUTTON -> {
+                            keyguardPrompt()
+                        }
+
+                        BiometricPrompt.ERROR_LOCKOUT -> {
+                            keyguardPrompt()
+                        }
+
+                        else -> {
+                            onError(
+                                labels.failedTitle,
+                                labels.failedExplainerWithError.format(errString.toString()),
+                            )
+                        }
+                    }
+                }
+
+                override fun onAuthenticationFailed() {
+                    super.onAuthenticationFailed()
+                    onError(labels.failedTitle, labels.failedExplainer)
+                }
+
+                override fun onAuthenticationSucceeded(result: BiometricPrompt.AuthenticationResult) {
+                    super.onAuthenticationSucceeded(result)
+                    onApproved()
+                }
+            },
+        )
+
+    when (biometricManager.canAuthenticate(authenticators)) {
+        BiometricManager.BIOMETRIC_SUCCESS -> biometricPrompt.authenticate(promptInfo)
+        else -> keyguardPrompt()
+    }
+}

commonsUI/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/ui/privacylock/DeviceAuthenticator.kt

@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.ui.privacylock
+
+import androidx.compose.runtime.Composable
+
+/** Asks the user to prove it is them (biometrics or the device PIN) before a sensitive action. */
+fun interface DeviceAuthenticator {
+    /**
+     * Prompts with [title] and runs [onApproved] once the user passes. A device without a screen
+     * lock approves at once. [onError] gets a title and a message for a failed attempt.
+     */
+    fun authenticate(
+        title: String,
+        onApproved: () -> Unit,
+        onError: (title: String, message: String) -> Unit,
+    )
+}
+
+/**
+ * The platform's device-credential prompt. Android shows BiometricPrompt (strong biometrics or
+ * the device credential) and falls back to the keyguard screen; desktop and iOS have no prompt
+ * wired yet and approve at once, as Android does on a device without a screen lock.
+ */
+@Composable
+expect fun rememberDeviceAuthenticator(): DeviceAuthenticator

commonsUI/src/iosMain/kotlin/com/vitorpamplona/amethyst/commons/ui/privacylock/DeviceAuthenticator.ios.kt

@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.ui.privacylock
+
+import androidx.compose.runtime.Composable
+
+private val ApproveAtOnce = DeviceAuthenticator { _, onApproved, _ -> onApproved() }
+
+/** No device-credential prompt wired on this platform yet; see the common declaration. */
+@Composable
+actual fun rememberDeviceAuthenticator(): DeviceAuthenticator = ApproveAtOnce

commonsUI/src/jvmMain/kotlin/com/vitorpamplona/amethyst/commons/ui/privacylock/DeviceAuthenticator.jvm.kt

@@ -0,0 +1,29 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.amethyst.commons.ui.privacylock
+
+import androidx.compose.runtime.Composable
+
+private val ApproveAtOnce = DeviceAuthenticator { _, onApproved, _ -> onApproved() }
+
+/** No device-credential prompt wired on this platform yet; see the common declaration. */
+@Composable
+actual fun rememberDeviceAuthenticator(): DeviceAuthenticator = ApproveAtOnce