Add BiometricPasswordInput

Variant of `PasswordInput` that only allows the password to be unmasked after the user has authenticated using `BiometricPrompt`.

core/ui/compose/designsystem/src/main/kotlin/app/k9mail/core/ui/compose/designsystem/atom/textfield/TextFieldOutlinedPassword.kt

@@ -55,6 +55,41 @@ fun TextFieldOutlinedPassword(
     )
 }
 
+@Composable
+fun TextFieldOutlinedPassword(
+    value: String,
+    onValueChange: (String) -> Unit,
+    isPasswordVisible: Boolean,
+    onPasswordVisibilityToggleClicked: () -> Unit,
+    modifier: Modifier = Modifier,
+    label: String? = null,
+    isEnabled: Boolean = true,
+    isReadOnly: Boolean = false,
+    isRequired: Boolean = false,
+    hasError: Boolean = false,
+) {
+    MaterialOutlinedTextField(
+        value = value,
+        onValueChange = onValueChange,
+        modifier = modifier,
+        enabled = isEnabled,
+        label = selectLabel(label, isRequired),
+        trailingIcon = selectTrailingIcon(
+            isEnabled = isEnabled,
+            isPasswordVisible = isPasswordVisible,
+            onClick = onPasswordVisibilityToggleClicked,
+        ),
+        readOnly = isReadOnly,
+        isError = hasError,
+        visualTransformation = selectVisualTransformation(
+            isEnabled = isEnabled,
+            isPasswordVisible = isPasswordVisible,
+        ),
+        keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Password),
+        singleLine = true,
+    )
+}
+
 private fun selectTrailingIcon(
     isEnabled: Boolean,
     isPasswordVisible: Boolean,

core/ui/compose/designsystem/src/main/kotlin/app/k9mail/core/ui/compose/designsystem/molecule/input/InputLayout.kt

@@ -11,7 +11,7 @@ import app.k9mail.core.ui.compose.designsystem.atom.text.TextCaption
 import app.k9mail.core.ui.compose.theme.MainTheme
 
 @Composable
-internal fun InputLayout(
+fun InputLayout(
     modifier: Modifier = Modifier,
     contentPadding: PaddingValues = inputContentPadding(),
     errorMessage: String? = null,

core/ui/compose/designsystem/src/test/kotlin/app/k9mail/core/ui/compose/designsystem/atom/textfield/TextFieldOutlinedPasswordKtTest.kt

@@ -8,6 +8,8 @@ import androidx.compose.ui.test.onNodeWithText
 import androidx.compose.ui.test.performClick
 import app.k9mail.core.ui.compose.designsystem.R
 import app.k9mail.core.ui.compose.testing.ComposeTest
+import assertk.assertThat
+import assertk.assertions.isTrue
 import org.junit.Test
 
 private const val PASSWORD = "Password input"
@@ -84,6 +86,51 @@ class TextFieldOutlinedPasswordKtTest : ComposeTest() {
         onShowPasswordNode().assertIsDisplayed()
     }
 
+    @Test
+    fun `should call callback when password visibility toggle icon is clicked`() = runComposeTest {
+        var clicked = false
+        setContent {
+            TextFieldOutlinedPassword(
+                value = PASSWORD,
+                onValueChange = {},
+                isPasswordVisible = false,
+                onPasswordVisibilityToggleClicked = { clicked = true },
+            )
+        }
+
+        onShowPasswordNode().performClick()
+
+        assertThat(clicked).isTrue()
+    }
+
+    @Test
+    fun `should display password when isPasswordVisible = true`() = runComposeTest {
+        setContent {
+            TextFieldOutlinedPassword(
+                value = PASSWORD,
+                onValueChange = {},
+                isPasswordVisible = true,
+                onPasswordVisibilityToggleClicked = {},
+            )
+        }
+
+        onNodeWithText(PASSWORD).assertIsDisplayed()
+    }
+
+    @Test
+    fun `should not display password when isPasswordVisible = false`() = runComposeTest {
+        setContent {
+            TextFieldOutlinedPassword(
+                value = PASSWORD,
+                onValueChange = {},
+                isPasswordVisible = false,
+                onPasswordVisibilityToggleClicked = {},
+            )
+        }
+
+        onNodeWithText(PASSWORD).assertDoesNotExist()
+    }
+
     private fun SemanticsNodeInteractionsProvider.onShowPasswordNode(): SemanticsNodeInteraction {
         return onNodeWithContentDescription(
             getString(R.string.designsystem_atom_password_textfield_show_password),

feature/account/server/settings/build.gradle.kts

@@ -24,6 +24,7 @@ dependencies {
     implementation(projects.mail.protocols.imap)
 
     implementation(projects.feature.account.common)
+    implementation(libs.androidx.biometric)
 
     testImplementation(projects.core.ui.compose.testing)
 }

feature/account/server/settings/src/main/kotlin/app/k9mail/feature/account/server/settings/ui/common/BiometricPasswordInput.kt

@@ -0,0 +1,72 @@
+package app.k9mail.feature.account.server.settings.ui.common
+
+import androidx.biometric.BiometricPrompt
+import androidx.compose.foundation.layout.PaddingValues
+import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.res.stringResource
+import androidx.fragment.app.FragmentActivity
+import app.k9mail.core.ui.compose.designsystem.molecule.input.InputLayout
+import app.k9mail.core.ui.compose.designsystem.molecule.input.PasswordInput
+import app.k9mail.core.ui.compose.designsystem.molecule.input.inputContentPadding
+import app.k9mail.feature.account.server.settings.R
+import kotlinx.coroutines.delay
+import app.k9mail.core.ui.compose.designsystem.R as RDesign
+
+private const val SHOW_WARNING_DURATION = 5000L
+
+/**
+ * Variant of [PasswordInput] that only allows the password to be unmasked after the user has authenticated using
+ * [BiometricPrompt].
+ *
+ * Note: Due to limitations of [BiometricPrompt] this composable can only be used inside a [FragmentActivity].
+ */
+@Composable
+fun BiometricPasswordInput(
+    onPasswordChange: (String) -> Unit,
+    modifier: Modifier = Modifier,
+    password: String = "",
+    isRequired: Boolean = false,
+    errorMessage: String? = null,
+    contentPadding: PaddingValues = inputContentPadding(),
+) {
+    var biometricWarning by remember { mutableStateOf<String?>(value = null) }
+
+    LaunchedEffect(key1 = biometricWarning) {
+        if (biometricWarning != null) {
+            delay(SHOW_WARNING_DURATION)
+            biometricWarning = null
+        }
+    }
+
+    InputLayout(
+        modifier = modifier,
+        contentPadding = contentPadding,
+        errorMessage = errorMessage,
+        warningMessage = biometricWarning,
+    ) {
+        val title = stringResource(R.string.account_server_settings_password_authentication_title)
+        val subtitle = stringResource(R.string.account_server_settings_password_authentication_subtitle)
+        val needScreenLockMessage =
+            stringResource(R.string.account_server_settings_password_authentication_screen_lock_required)
+
+        TextFieldOutlinedPasswordBiometric(
+            value = password,
+            onValueChange = onPasswordChange,
+            authenticationTitle = title,
+            authenticationSubtitle = subtitle,
+            needScreenLockMessage = needScreenLockMessage,
+            onWarningChange = { biometricWarning = it?.toString() },
+            label = stringResource(id = RDesign.string.designsystem_molecule_password_input_label),
+            isRequired = isRequired,
+            hasError = errorMessage != null,
+            modifier = Modifier.fillMaxWidth(),
+        )
+    }
+}

feature/account/server/settings/src/main/kotlin/app/k9mail/feature/account/server/settings/ui/common/TextFieldOutlinedPasswordBiometric.kt

@@ -0,0 +1,131 @@
+package app.k9mail.feature.account.server.settings.ui.common
+
+import android.view.WindowManager
+import androidx.biometric.BiometricManager
+import androidx.biometric.BiometricPrompt
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.DisposableEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.saveable.rememberSaveable
+import androidx.compose.runtime.setValue
+import androidx.compose.ui.Modifier
+import androidx.fragment.app.FragmentActivity
+import app.k9mail.core.ui.compose.common.activity.LocalActivity
+import app.k9mail.core.ui.compose.designsystem.atom.textfield.TextFieldOutlinedPassword
+
+/**
+ * Variant of [TextFieldOutlinedPassword] that only allows the password to be unmasked after the user has authenticated
+ * using [BiometricPrompt].
+ *
+ * Note: Due to limitations of [BiometricPrompt] this composable can only be used inside a [FragmentActivity].
+ */
+@Suppress("LongParameterList")
+@Composable
+fun TextFieldOutlinedPasswordBiometric(
+    value: String,
+    onValueChange: (String) -> Unit,
+    authenticationTitle: String,
+    authenticationSubtitle: String,
+    needScreenLockMessage: String,
+    onWarningChange: (CharSequence?) -> Unit,
+    modifier: Modifier = Modifier,
+    label: String? = null,
+    isEnabled: Boolean = true,
+    isReadOnly: Boolean = false,
+    isRequired: Boolean = false,
+    hasError: Boolean = false,
+) {
+    var isPasswordVisible by rememberSaveable { mutableStateOf(false) }
+    var isAuthenticated by rememberSaveable { mutableStateOf(false) }
+    var isAuthenticationRequired by rememberSaveable { mutableStateOf(true) }
+
+    // If the entire password was removed, we allow the user to unmask the text field without requiring authentication.
+    if (value.isEmpty()) {
+        isAuthenticationRequired = false
+    }
+
+    val activity = LocalActivity.current as FragmentActivity
+
+    TextFieldOutlinedPassword(
+        value = value,
+        onValueChange = onValueChange,
+        modifier = modifier,
+        label = label,
+        isEnabled = isEnabled,
+        isReadOnly = isReadOnly,
+        isRequired = isRequired,
+        hasError = hasError,
+        isPasswordVisible = isPasswordVisible,
+        onPasswordVisibilityToggleClicked = {
+            if (!isAuthenticationRequired || isAuthenticated) {
+                isPasswordVisible = !isPasswordVisible
+                activity.setSecure(isPasswordVisible)
+            } else {
+                showBiometricPrompt(
+                    activity,
+                    authenticationTitle,
+                    authenticationSubtitle,
+                    needScreenLockMessage,
+                    onAuthSuccess = {
+                        isAuthenticated = true
+                        isPasswordVisible = true
+                        onWarningChange(null)
+                        activity.setSecure(true)
+                    },
+                    onAuthError = onWarningChange,
+                )
+            }
+        },
+    )
+
+    DisposableEffect(key1 = "secureWindow") {
+        activity.setSecure(isPasswordVisible)
+
+        onDispose {
+            activity.setSecure(false)
+        }
+    }
+}
+
+private fun showBiometricPrompt(
+    activity: FragmentActivity,
+    title: String,
+    subtitle: String,
+    needScreenLockMessage: String,
+    onAuthSuccess: () -> Unit,
+    onAuthError: (CharSequence) -> Unit,
+) {
+    val authenticationCallback = object : BiometricPrompt.AuthenticationCallback() {
+        override fun onAuthenticationSucceeded(result: BiometricPrompt.AuthenticationResult) {
+            onAuthSuccess()
+        }
+
+        override fun onAuthenticationError(errorCode: Int, errString: CharSequence) {
+            if (errorCode == BiometricPrompt.ERROR_HW_NOT_PRESENT ||
+                errorCode == BiometricPrompt.ERROR_NO_DEVICE_CREDENTIAL ||
+                errorCode == BiometricPrompt.ERROR_NO_BIOMETRICS
+            ) {
+                onAuthError(needScreenLockMessage)
+            } else if (errString.isNotEmpty()) {
+                onAuthError(errString)
+            }
+        }
+    }
+
+    val promptInfo = BiometricPrompt.PromptInfo.Builder()
+        .setAllowedAuthenticators(
+            BiometricManager.Authenticators.BIOMETRIC_STRONG or
+                BiometricManager.Authenticators.BIOMETRIC_WEAK or
+                BiometricManager.Authenticators.DEVICE_CREDENTIAL,
+        )
+        .setTitle(title)
+        .setSubtitle(subtitle)
+        .build()
+
+    BiometricPrompt(activity, authenticationCallback).authenticate(promptInfo)
+}
+
+private fun FragmentActivity.setSecure(secure: Boolean) {
+    window.setFlags(if (secure) WindowManager.LayoutParams.FLAG_SECURE else 0, WindowManager.LayoutParams.FLAG_SECURE)
+}

feature/account/server/settings/src/main/res/values/strings.xml

@@ -35,4 +35,9 @@
     <string name="account_server_settings_validation_error_username_required">Username is required.</string>
     <string name="account_server_settings_validation_error_password_required">Password is required.</string>
     <string name="account_server_settings_validation_error_imap_prefix_blank">Imap prefix can\'t be blank.</string>
+
+    <string name="account_server_settings_password_authentication_title">Verify your identity</string>
+    <string name="account_server_settings_password_authentication_subtitle">Unlock to view your password</string>
+    <!-- Please use the same translation for "screen lock" as is used in the 'Security' section in Android's settings app -->
+    <string name="account_server_settings_password_authentication_screen_lock_required">To view your password here, enable screen lock on this device.</string>
 </resources>