Attributes validation + basic error handling + improvements!

Signed-off-by: Iván Ávalos <avalos@disroot.org>

17 files changed, 333 insertions, 106 deletions

diff --git a/anastasis/src/main/java/net/taler/anastasis/MainActivity.kt b/anastasis/src/main/java/net/taler/anastasis/MainActivity.kt
index 8d6a8ad..653d8a5 100644
--- a/anastasis/src/main/java/net/taler/anastasis/MainActivity.kt
+++ b/anastasis/src/main/java/net/taler/anastasis/MainActivity.kt
@@ -20,6 +20,7 @@ import net.taler.anastasis.ui.backup.SelectAuthMethodsScreen
 import net.taler.anastasis.ui.common.SelectContinentScreen
 import net.taler.anastasis.ui.common.SelectCountryScreen
 import net.taler.anastasis.ui.common.SelectUserAttributesScreen
+import net.taler.anastasis.ui.dialogs.ErrorDialog
 import net.taler.anastasis.ui.home.HomeScreen
 import net.taler.anastasis.ui.theme.AnastasisTheme
 import net.taler.anastasis.viewmodels.ReducerViewModel
@@ -54,6 +55,13 @@ class MainActivity : ComponentActivity() {
 fun MainNavHost(
     viewModel: ReducerViewModel = hiltViewModel(),
 ) {
+    val error by viewModel.reducerError.collectAsState()
+    error?.let {
+        ErrorDialog(error = it) {
+            viewModel.cleanError()
+        }
+    }
+
     val navRoute by viewModel.navRoute.collectAsState()
     when (navRoute) {
         Routes.Home.route -> {
diff --git a/anastasis/src/main/java/net/taler/anastasis/backend/AnastasisReducerApi.kt b/anastasis/src/main/java/net/taler/anastasis/backend/AnastasisReducerApi.kt
index c179d8f..9070490 100644
--- a/anastasis/src/main/java/net/taler/anastasis/backend/AnastasisReducerApi.kt
+++ b/anastasis/src/main/java/net/taler/anastasis/backend/AnastasisReducerApi.kt
@@ -22,10 +22,11 @@ import kotlinx.coroutines.GlobalScope
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.withContext
 import kotlinx.serialization.json.decodeFromJsonElement
-import net.taler.anastasis.Utils.encodeToNativeJson
+import net.taler.anastasis.shared.Utils.encodeToNativeJson
 import net.taler.anastasis.models.ReducerState
 import net.taler.common.ApiResponse
 import net.taler.common.ApiResponse.*
+import net.taler.common.TalerErrorCode
 import net.taler.common.TalerErrorCode.NONE
 import org.json.JSONObject
 
@@ -74,10 +75,24 @@ class AnastasisReducerApi() {
         try {
             when (val response = sendRequest("anastasisReduce", body)) {
                 is Response -> {
-                    val t = json.decodeFromJsonElement<ReducerState>(response.result)
-                    WalletResponse.Success(t)
+                    when (val t = json.decodeFromJsonElement<ReducerState>(response.result)) {
+                        is ReducerState.Recovery, is ReducerState.Backup -> {
+                            WalletResponse.Success(t)
+                        }
+                        is ReducerState.Error -> {
+                            WalletResponse.Error(
+                                TalerErrorInfo(
+                                    code = TalerErrorCode.fromInt(t.code),
+                                    hint = t.hint,
+                                )
+                            )
+                        }
+                    }
+                }
+                is Error -> {
+                    val error: TalerErrorInfo = json.decodeFromJsonElement(response.error)
+                    WalletResponse.Error(error)
                 }
-                is Error -> error("invalid reducer response")
             }
         } catch (e: Exception) {
             val info = TalerErrorInfo(NONE, "", e.toString())
@@ -99,8 +114,19 @@ class AnastasisReducerApi() {
         try {
             when (val response = sendRequest("anastasisReduce", body)) {
                 is Response -> {
-                    val t = json.decodeFromJsonElement<ReducerState>(response.result)
-                    WalletResponse.Success(t)
+                    when (val t = json.decodeFromJsonElement<ReducerState>(response.result)) {
+                        is ReducerState.Recovery, is ReducerState.Backup -> {
+                            WalletResponse.Success(t)
+                        }
+                        is ReducerState.Error -> {
+                            WalletResponse.Error(
+                                TalerErrorInfo(
+                                    code = TalerErrorCode.fromInt(t.code),
+                                    hint = t.hint,
+                                )
+                            )
+                        }
+                    }
                 }
                 is Error -> error("invalid reducer response")
             }
diff --git a/anastasis/src/main/java/net/taler/anastasis/models/ReducerArgs.kt b/anastasis/src/main/java/net/taler/anastasis/models/ReducerArgs.kt
index c87e76d..58e0223 100644
--- a/anastasis/src/main/java/net/taler/anastasis/models/ReducerArgs.kt
+++ b/anastasis/src/main/java/net/taler/anastasis/models/ReducerArgs.kt
@@ -18,6 +18,7 @@ package net.taler.anastasis.models
 
 import kotlinx.serialization.SerialName
 import kotlinx.serialization.Serializable
+import net.taler.common.Timestamp
 
 @Serializable
 sealed class ReducerArgs {
@@ -44,7 +45,17 @@ sealed class ReducerArgs {
 
     // TODO: ActionArgsEnterSecretName
 
-    // TODO: ActionArgsEnterSecret
+    @Serializable
+    data class EnterSecret(
+        val secret: Secret,
+        val expiration: Timestamp? = null,
+    ) {
+        @Serializable
+        data class Secret(
+            val value: String,
+            val mime: String? = null,
+        )
+    }
 
     @Serializable
     data class SelectContinent(
diff --git a/anastasis/src/main/java/net/taler/anastasis/reducers/ReducerManager.kt b/anastasis/src/main/java/net/taler/anastasis/reducers/ReducerManager.kt
index fd527f6..a074044 100644
--- a/anastasis/src/main/java/net/taler/anastasis/reducers/ReducerManager.kt
+++ b/anastasis/src/main/java/net/taler/anastasis/reducers/ReducerManager.kt
@@ -25,9 +25,10 @@ import kotlinx.coroutines.flow.launchIn
 import kotlinx.coroutines.flow.onEach
 import kotlinx.coroutines.launch
 import kotlinx.serialization.json.Json
-import net.taler.anastasis.Utils
-import net.taler.anastasis.Utils.encodeToNativeJson
+import net.taler.anastasis.shared.Utils
+import net.taler.anastasis.shared.Utils.encodeToNativeJson
 import net.taler.anastasis.backend.AnastasisReducerApi
+import net.taler.anastasis.backend.TalerErrorInfo
 import net.taler.anastasis.models.AuthenticationProviderStatus
 import net.taler.anastasis.models.ContinentInfo
 import net.taler.anastasis.models.CountryInfo
@@ -39,6 +40,7 @@ import kotlin.time.Duration.Companion.seconds
 
 class ReducerManager(
     private val state: MutableStateFlow<ReducerState?>,
+    private val error: MutableStateFlow<TalerErrorInfo?>,
     private val api: AnastasisReducerApi,
     private val scope: CoroutineScope,
 ) {
@@ -50,6 +52,14 @@ class ReducerManager(
 
     // TODO: error handling!
 
+    private fun onSuccess(newState: ReducerState) {
+        state.value = newState
+    }
+
+    private fun onError(info: TalerErrorInfo) {
+        error.value = info
+    }
+
     fun startBackup() = scope.launch {
         state.value = api.startBackup()
     }
@@ -61,18 +71,16 @@ class ReducerManager(
     fun back() = scope.launch {
         state.value?.let { initialState ->
             api.reduceAction(initialState, "back")
-                .onSuccess { newState ->
-                    state.value = newState
-                }
+                .onSuccess { onSuccess(it) }
+                .onError { onError(it) }
         }
     }
 
     fun next() = scope.launch {
         state.value?.let { initialState ->
             api.reduceAction(initialState, "next")
-                .onSuccess { newState ->
-                    state.value = newState
-                }
+                .onSuccess { onSuccess(it) }
+                .onError { onError(it) }
         }
     }
 
@@ -80,9 +88,9 @@ class ReducerManager(
         state.value?.let { initialState ->
             api.reduceAction(initialState, "select_continent") {
                 put("continent", continent.name)
-            }.onSuccess { newState ->
-                state.value = newState
             }
+                .onSuccess { onSuccess(it) }
+                .onError { onError(it) }
         }
     }
 
@@ -92,9 +100,9 @@ class ReducerManager(
                 put("country_code", country.code)
                 // TODO: stop hardcoding currency!
                 put("currency", "EUR")
-            }.onSuccess { newState ->
-                state.value = newState
             }
+                .onSuccess { onSuccess(it) }
+                .onError { onError(it) }
         }
     }
 
@@ -102,9 +110,9 @@ class ReducerManager(
         state.value?.let {  initialState ->
             api.reduceAction(initialState, "enter_user_attributes") {
                 put("identity_attributes", JSONObject(userAttributes))
-            }.onSuccess { newState ->
-                state.value = newState
             }
+                .onSuccess { onSuccess(it) }
+                .onError { onError(it) }
         }
     }
 
@@ -150,9 +158,8 @@ class ReducerManager(
     fun addAuthentication(args: ReducerArgs.AddAuthentication) = scope.launch {
         state.value?.let { initialState ->
             api.reduceAction(initialState, "add_authentication", args)
-                .onSuccess { newState ->
-                    state.value = newState
-                }
+                .onSuccess { onSuccess(it) }
+                .onError { onError(it) }
         }
     }
 
@@ -160,9 +167,9 @@ class ReducerManager(
         state.value?.let { initialState ->
             api.reduceAction(initialState, "delete_authentication") {
                 put("authentication_method", index)
-            }.onSuccess { newState ->
-                state.value = newState
             }
+                .onSuccess { onSuccess(it) }
+                .onError { onError(it) }
         }
     }
 
@@ -170,9 +177,9 @@ class ReducerManager(
         state.value?.let { initialState ->
             api.reduceAction(initialState, "add_policy") {
                 put("policy", Json.encodeToNativeJson(policy.methods))
-            }.onSuccess { newState ->
-                state.value = newState
-            }.onError { Log.d("ReducerManager", "$it") }
+            }
+                .onSuccess { onSuccess(it) }
+                .onError { onError(it) }
         }
     }
 
@@ -181,9 +188,9 @@ class ReducerManager(
             api.reduceAction(initialState, "update_policy") {
                 put("policy_index", index)
                 put("policy", Json.encodeToNativeJson(policy.methods))
-            }.onSuccess { newState ->
-                state.value = newState
             }
+                .onSuccess { onSuccess(it) }
+                .onError { onError(it) }
         }
     }
 
@@ -191,8 +198,26 @@ class ReducerManager(
         state.value?.let { initialState ->
             api.reduceAction(initialState, "delete_policy") {
                 put("policy_index", index)
-            }.onSuccess {  newState ->
-                state.value = newState
+            }
+                .onSuccess { onSuccess(it) }
+                .onError { onError(it) }
+        }
+    }
+
+    fun backupSecret(
+        name: String,
+        args: ReducerArgs.EnterSecret,
+    ) = scope.launch {
+        state.value?.let { initialState ->
+            api.reduceAction(initialState, "enter_secret", args).onSuccess { newState ->
+                scope.launch {
+                    api.reduceAction(newState, "enter_secret_name") {
+                        put("name", name)
+                    }.onSuccess { newNewState ->
+                        this@ReducerManager.onSuccess(newNewState)
+                        this@ReducerManager.next()
+                    }.onError { onError(it) }
+                }
             }
         }
     }
diff --git a/anastasis/src/main/java/net/taler/anastasis/shared/FieldStatus.kt b/anastasis/src/main/java/net/taler/anastasis/shared/FieldStatus.kt
new file mode 100644
index 0000000..a471e20
--- /dev/null
+++ b/anastasis/src/main/java/net/taler/anastasis/shared/FieldStatus.kt
@@ -0,0 +1,26 @@
+/*
+ * This file is part of GNU Taler
+ * (C) 2023 Taler Systems S.A.
+ *
+ * GNU Taler is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License as published by the Free Software
+ * Foundation; either version 3, or (at your option) any later version.
+ *
+ * GNU Taler is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+ * A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * GNU Taler; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+ */
+
+package net.taler.anastasis.shared
+
+import net.taler.anastasis.R
+
+enum class FieldStatus(val msgRes: Int?, val error: Boolean) {
+    Null(msgRes = null, error = false),
+    Blank(msgRes = R.string.field_empty, error = true),
+    Invalid(msgRes = R.string.field_invalid, error = true),
+    Valid(msgRes = null, error = false);
+}
\ No newline at end of file
diff --git a/anastasis/src/main/java/net/taler/anastasis/Utils.kt b/anastasis/src/main/java/net/taler/anastasis/shared/Utils.kt
index 58e6b89..916dd36 100644
--- a/anastasis/src/main/java/net/taler/anastasis/Utils.kt
+++ b/anastasis/src/main/java/net/taler/anastasis/shared/Utils.kt
@@ -14,7 +14,7 @@
  * GNU Taler; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
  */
 
-package net.taler.anastasis
+package net.taler.anastasis.shared
 
 import android.os.Build
 import io.matthewnelson.encoding.base32.Base32
@@ -22,8 +22,11 @@ import io.matthewnelson.encoding.core.Decoder.Companion.decodeToByteArray
 import io.matthewnelson.encoding.core.Encoder.Companion.encodeToString
 import kotlinx.coroutines.delay
 import kotlinx.coroutines.flow.flow
+import kotlinx.datetime.Clock
 import kotlinx.datetime.LocalDate
+import kotlinx.datetime.TimeZone
 import kotlinx.datetime.toJavaLocalDate
+import kotlinx.datetime.toLocalDateTime
 import kotlinx.serialization.encodeToString
 import kotlinx.serialization.json.Json
 import org.json.JSONArray
@@ -37,15 +40,18 @@ import kotlin.time.Duration
 object Utils {
     fun formatDate(date: LocalDate): String {
         val javaDate = date.toJavaLocalDate()
-        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
+        return if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
             val formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd")
-            return javaDate.format(formatter)
+            javaDate.format(formatter)
         } else {
             val formatter = SimpleDateFormat("yyyy-MM-dd", Locale.getDefault())
-            return formatter.format(date)
+            formatter.format(date)
         }
     }
 
+    val currentDate: LocalDate
+        get() = Clock.System.now().toLocalDateTime(TimeZone.currentSystemDefault()).date
+
     inline fun <reified T> Json.encodeToNativeJson(value: T): JSONObject =
         JSONObject(encodeToString(value))
 
@@ -56,6 +62,9 @@ object Utils {
         .toByteArray(Charset.defaultCharset())
         .encodeToString(Base32.Crockford)
 
+    fun encodeBase32 (input: ByteArray) = input
+        .encodeToString(Base32.Crockford)
+
     fun decodeBase32 (input: String) = input
         .decodeToByteArray(Base32.Crockford)
         .toString(Charset.defaultCharset())
diff --git a/anastasis/src/main/java/net/taler/anastasis/ui/backup/SelectAuthMethodsScreen.kt b/anastasis/src/main/java/net/taler/anastasis/ui/backup/SelectAuthMethodsScreen.kt
index 6d8f0ff..9234f99 100644
--- a/anastasis/src/main/java/net/taler/anastasis/ui/backup/SelectAuthMethodsScreen.kt
+++ b/anastasis/src/main/java/net/taler/anastasis/ui/backup/SelectAuthMethodsScreen.kt
@@ -48,7 +48,7 @@ import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.unit.dp
 import androidx.hilt.navigation.compose.hiltViewModel
 import net.taler.anastasis.R
-import net.taler.anastasis.Utils
+import net.taler.anastasis.shared.Utils
 import net.taler.anastasis.models.AuthMethod
 import net.taler.anastasis.models.AuthenticationProviderStatus
 import net.taler.anastasis.models.ReducerArgs
diff --git a/anastasis/src/main/java/net/taler/anastasis/ui/common/SelectContinentScreen.kt b/anastasis/src/main/java/net/taler/anastasis/ui/common/SelectContinentScreen.kt
index 303b82e..eacbea4 100644
--- a/anastasis/src/main/java/net/taler/anastasis/ui/common/SelectContinentScreen.kt
+++ b/anastasis/src/main/java/net/taler/anastasis/ui/common/SelectContinentScreen.kt
@@ -30,7 +30,6 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.res.stringResource
 import androidx.hilt.navigation.compose.hiltViewModel
 import net.taler.anastasis.R
-import net.taler.anastasis.models.ContinentInfo
 import net.taler.anastasis.models.ReducerState
 import net.taler.anastasis.ui.reusable.components.Picker
 import net.taler.anastasis.ui.reusable.pages.WizardPage
@@ -48,15 +47,25 @@ fun SelectContinentScreen(
         else -> error("invalid reducer state type")
     } ?: emptyList()
 
-    var selectedContinent by remember { mutableStateOf<ContinentInfo?>(null) }
+    val selectedContinent = when (val state = reducerState) {
+        is ReducerState.Backup -> state.selectedContinent
+        is ReducerState.Recovery -> state.selectedContinent
+        else -> error("invalid reducer state type")
+    }
+
+    var localContinent by remember {
+        mutableStateOf(selectedContinent?.let { selected ->
+            continents.find { it.name == selected }
+        })
+    }
 
     WizardPage(
         title = stringResource(R.string.select_continent_title),
         showPrev = false,
-        enableNext = selectedContinent != null,
+        enableNext = localContinent != null,
         onBackClicked = { viewModel.goHome() },
         onNextClicked = {
-            selectedContinent?.let {
+            localContinent?.let {
                 viewModel.reducerManager.selectContinent(it)
             }
         },
@@ -69,11 +78,11 @@ fun SelectContinentScreen(
         ) {
             Picker(
                 label = stringResource(R.string.continent),
-                initialOption = selectedContinent?.name,
+                initialOption = localContinent?.name,
                 options = continents.map { it.name }.toSet(),
                 onOptionChanged = { option ->
                     continents.find { it.name == option }?.let { continent ->
-                        selectedContinent = continent
+                        localContinent = continent
                     }
                 },
             )
diff --git a/anastasis/src/main/java/net/taler/anastasis/ui/common/SelectCountryScreen.kt b/anastasis/src/main/java/net/taler/anastasis/ui/common/SelectCountryScreen.kt
index 4f5d753..4c8a32e 100644
--- a/anastasis/src/main/java/net/taler/anastasis/ui/common/SelectCountryScreen.kt
+++ b/anastasis/src/main/java/net/taler/anastasis/ui/common/SelectCountryScreen.kt
@@ -30,7 +30,6 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.res.stringResource
 import androidx.hilt.navigation.compose.hiltViewModel
 import net.taler.anastasis.R
-import net.taler.anastasis.models.CountryInfo
 import net.taler.anastasis.models.ReducerState
 import net.taler.anastasis.ui.reusable.components.Picker
 import net.taler.anastasis.ui.reusable.pages.WizardPage
@@ -48,15 +47,25 @@ fun SelectCountryScreen(
         else -> error("invalid reducer state type")
     } ?: emptyList()
 
-    var selectedCountry by remember { mutableStateOf<CountryInfo?>(null) }
+    val selectedCountry = when (val state = reducerState) {
+        is ReducerState.Backup -> state.selectedCountry
+        is ReducerState.Recovery -> state.selectedCountry
+        else -> error("invalid reducer state type")
+    }
+
+    var localCountry by remember {
+        mutableStateOf(selectedCountry?.let { selected ->
+            countries.find { it.code == selected }
+        })
+    }
 
     WizardPage(
         title = stringResource(R.string.select_country_title),
-        enableNext = selectedCountry != null,
+        enableNext = localCountry != null,
         onBackClicked = { viewModel.goHome() },
         onPrevClicked = { viewModel.goBack() },
         onNextClicked = {
-            selectedCountry?.let {
+            localCountry?.let {
                 viewModel.reducerManager.selectCountry(it)
             }
         },
@@ -69,11 +78,11 @@ fun SelectCountryScreen(
         ) {
             Picker(
                 label = stringResource(R.string.country),
-                initialOption = selectedCountry?.name,
+                initialOption = localCountry?.name,
                 options = countries.map { it.name }.toSet(),
                 onOptionChanged = { option ->
                     countries.find { it.name == option }?.let { country ->
-                        selectedCountry = country
+                        localCountry = country
                     }
                 },
             )
diff --git a/anastasis/src/main/java/net/taler/anastasis/ui/common/SelectUserAttributesScreen.kt b/anastasis/src/main/java/net/taler/anastasis/ui/common/SelectUserAttributesScreen.kt
index 6de45b5..e0badcb 100644
--- a/anastasis/src/main/java/net/taler/anastasis/ui/common/SelectUserAttributesScreen.kt
+++ b/anastasis/src/main/java/net/taler/anastasis/ui/common/SelectUserAttributesScreen.kt
@@ -31,20 +31,21 @@ import androidx.compose.runtime.Composable
 import androidx.compose.runtime.collectAsState
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateMapOf
-import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
-import androidx.compose.runtime.setValue
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.input.nestedscroll.nestedScroll
 import androidx.compose.ui.res.stringResource
 import androidx.hilt.navigation.compose.hiltViewModel
+import kotlinx.datetime.toLocalDate
 import net.taler.anastasis.R
+import net.taler.anastasis.shared.Utils
 import net.taler.anastasis.models.ReducerState
+import net.taler.anastasis.models.UserAttributeSpec
+import net.taler.anastasis.shared.FieldStatus
 import net.taler.anastasis.ui.reusable.components.DatePickerField
 import net.taler.anastasis.ui.reusable.pages.WizardPage
 import net.taler.anastasis.ui.theme.LocalSpacing
 import net.taler.anastasis.viewmodels.ReducerViewModel
-import java.util.Calendar
 
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
@@ -58,7 +59,15 @@ fun SelectUserAttributesScreen(
         else -> error("invalid reducer state type")
     } ?: emptyList()
 
-    val values = remember { mutableStateMapOf<String, String>() }
+    val identityAttributes = when(val state = reducerState) {
+        is ReducerState.Backup -> state.identityAttributes
+        is ReducerState.Recovery -> state.identityAttributes
+        else -> error("invalid reducer state type")
+    } ?: emptyMap()
+
+    val values = remember { mutableStateMapOf(
+        *identityAttributes.toList().toTypedArray()
+    ) }
 
     WizardPage(
         title = stringResource(R.string.select_user_attributes_title),
@@ -67,43 +76,72 @@ fun SelectUserAttributesScreen(
         onNextClicked = {
             viewModel.reducerManager.enterUserAttributes(values)
         },
-    ) {
+        enableNext = userAttributes.fold(true) { a, b ->
+            a && (fieldStatus(b, values[b.name]) == FieldStatus.Valid)
+        }
+    ) { scrollConnection ->
         LazyColumn(
             modifier = Modifier
                 .fillMaxSize()
-                .nestedScroll(it)
-                .padding(LocalSpacing.current.medium),
+                .nestedScroll(scrollConnection),
             verticalArrangement = Arrangement.Top,
         ) {
             items(items = userAttributes) { attr ->
+                val status = fieldStatus(attr, values[attr.name])
+                val supportingText: @Composable () -> Unit = @Composable {
+                    status.msgRes?.let {
+                        Text(stringResource(it))
+                    } ?: if (attr.optional == true) {
+                        Text(stringResource(R.string.field_optional))
+                    } else null
+                }
                 when (attr.type) {
                     "string" -> OutlinedTextField(
-                        modifier = Modifier.fillMaxWidth(),
+                        modifier = Modifier
+                            .padding(
+                                start = LocalSpacing.current.medium,
+                                end = LocalSpacing.current.medium,
+                            )
+                            .fillMaxWidth(),
                         value = values[attr.name] ?: "",
                         onValueChange = { values[attr.name] = it },
+                        isError = status.error,
+                        supportingText = supportingText,
                         label = { Text(attr.label) },
                     )
-                    "date" -> @Composable {
-                        val cal = Calendar.getInstance()
-                        var yy by remember { mutableStateOf(cal.get(Calendar.YEAR)) }
-                        var mm by remember { mutableStateOf(cal.get(Calendar.MONTH)) }
-                        var dd by remember { mutableStateOf(cal.get(Calendar.DAY_OF_MONTH)) }
-                        DatePickerField(
-                            modifier = Modifier.fillMaxWidth(),
-                            label = attr.label,
-                            yy = yy,
-                            mm = mm,
-                            dd = dd,
-                            onDateSelected = { y, m, d ->
-                                yy = y
-                                mm = m
-                                dd = d
-                            },
-                        )
-                    }
+                    "date" -> DatePickerField(
+                        modifier = Modifier
+                            .padding(
+                                start = LocalSpacing.current.medium,
+                                end = LocalSpacing.current.medium,
+                            )
+                            .fillMaxWidth(),
+                        label = attr.label,
+                        isError = status.error,
+                        supportingText = supportingText,
+                        date = values[attr.name]?.toLocalDate(),
+                        onDateSelected = { date ->
+                            values[attr.name] = Utils.formatDate(date)
+                        },
+                    )
                 }
                 Spacer(Modifier.height(LocalSpacing.current.small))
             }
         }
     }
+}
+
+fun fieldStatus(
+    field: UserAttributeSpec,
+    value: String? = null,
+): FieldStatus = if (value == null) {
+    FieldStatus.Null
+} else {
+    if (value.isNotBlank()) {
+        field.validationRegex?.toRegex()?.let {
+            if (value.matches(it))
+                FieldStatus.Valid else FieldStatus.Invalid
+        } ?: FieldStatus.Valid
+    } else if (field.optional == true)
+        FieldStatus.Valid else FieldStatus.Blank
 }
\ No newline at end of file
diff --git a/anastasis/src/main/java/net/taler/anastasis/ui/dialogs/EditMethodDialog.kt b/anastasis/src/main/java/net/taler/anastasis/ui/dialogs/EditMethodDialog.kt
index f8b580e..2b2f776 100644
--- a/anastasis/src/main/java/net/taler/anastasis/ui/dialogs/EditMethodDialog.kt
+++ b/anastasis/src/main/java/net/taler/anastasis/ui/dialogs/EditMethodDialog.kt
@@ -26,7 +26,7 @@ import androidx.compose.runtime.remember
 import androidx.compose.runtime.setValue
 import androidx.compose.ui.res.stringResource
 import net.taler.anastasis.R
-import net.taler.anastasis.Utils
+import net.taler.anastasis.shared.Utils
 import net.taler.anastasis.models.AuthMethod
 import net.taler.anastasis.ui.forms.EditQuestionForm
 
diff --git a/anastasis/src/main/java/net/taler/anastasis/ui/dialogs/EditPolicyDialog.kt b/anastasis/src/main/java/net/taler/anastasis/ui/dialogs/EditPolicyDialog.kt
index 8ec3662..09cd564 100644
--- a/anastasis/src/main/java/net/taler/anastasis/ui/dialogs/EditPolicyDialog.kt
+++ b/anastasis/src/main/java/net/taler/anastasis/ui/dialogs/EditPolicyDialog.kt
@@ -17,6 +17,8 @@
 package net.taler.anastasis.ui.dialogs
 
 import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.verticalScroll
 import androidx.compose.material3.AlertDialog
 import androidx.compose.material3.Text
 import androidx.compose.material3.TextButton
@@ -42,13 +44,16 @@ fun EditPolicyDialog(
     onCancel: () -> Unit,
 ) {
     var localPolicy by remember { mutableStateOf(policy) }
+    val scrollState = rememberScrollState()
 
     AlertDialog(
         onDismissRequest = onCancel,
         title = { Text(stringResource(R.string.add_policy)) },
         text = {
             EditPolicyForm(
-                modifier = Modifier.fillMaxWidth(),
+                modifier = Modifier
+                    .fillMaxWidth()
+                    .verticalScroll(scrollState),
                 policy = localPolicy,
                 methods = methods,
                 providers = providers,
diff --git a/anastasis/src/main/java/net/taler/anastasis/ui/dialogs/ErrorDialog.kt b/anastasis/src/main/java/net/taler/anastasis/ui/dialogs/ErrorDialog.kt
new file mode 100644
index 0000000..40e4534
--- /dev/null
+++ b/anastasis/src/main/java/net/taler/anastasis/ui/dialogs/ErrorDialog.kt
@@ -0,0 +1,44 @@
+/*
+ * This file is part of GNU Taler
+ * (C) 2023 Taler Systems S.A.
+ *
+ * GNU Taler is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License as published by the Free Software
+ * Foundation; either version 3, or (at your option) any later version.
+ *
+ * GNU Taler is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+ * A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * GNU Taler; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+ */
+
+package net.taler.anastasis.ui.dialogs
+
+import androidx.compose.material3.AlertDialog
+import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.res.stringResource
+import net.taler.anastasis.R
+import net.taler.anastasis.backend.TalerErrorInfo
+
+@Composable
+fun ErrorDialog(
+    error: TalerErrorInfo,
+    onCancel: () -> Unit,
+) {
+    AlertDialog(
+        onDismissRequest = onCancel,
+        title = { Text(stringResource(R.string.error)) },
+        text = { Text(error.hint ?: error.code.name) },
+        confirmButton = {
+            TextButton(onClick = {
+                onCancel()
+            }) {
+                Text(stringResource(R.string.close))
+            }
+        },
+    )
+}
\ No newline at end of file
diff --git a/anastasis/src/main/java/net/taler/anastasis/ui/reusable/components/DatePickerField.kt b/anastasis/src/main/java/net/taler/anastasis/ui/reusable/components/DatePickerField.kt
index 545d5b1..584ee80 100644
--- a/anastasis/src/main/java/net/taler/anastasis/ui/reusable/components/DatePickerField.kt
+++ b/anastasis/src/main/java/net/taler/anastasis/ui/reusable/components/DatePickerField.kt
@@ -40,32 +40,41 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.tooling.preview.Preview
 import kotlinx.datetime.LocalDate
-import net.taler.anastasis.Utils
+import net.taler.anastasis.shared.Utils
 import net.taler.anastasis.ui.theme.LocalSpacing
-import java.util.Calendar
 
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
 fun DatePickerField(
     modifier: Modifier = Modifier,
     label: String,
-    yy: Int,
-    mm: Int,
-    dd: Int,
-    onDateSelected: (yy: Int, mm: Int, dd: Int) -> Unit,
+    isError: Boolean = false,
+    supportingText: (@Composable () -> Unit)? = null,
+    date: LocalDate?,
+    onDateSelected: (date: LocalDate) -> Unit,
 ) {
+    val now = Utils.currentDate
     val dialog = DatePickerDialog(
         LocalContext.current,
         { _: DatePicker, y: Int, m: Int, d: Int ->
-            onDateSelected(y, m, d)
-        }, yy, mm, dd,
+            onDateSelected(LocalDate(
+                year = y,
+                monthNumber = m + 1,
+                dayOfMonth = d,
+            ))
+        },
+        date?.year ?: now.year,
+        (date?.monthNumber ?: now.monthNumber) - 1,
+        date?.dayOfMonth ?: now.dayOfMonth,
     )
 
     OutlinedTextField(
         modifier = modifier,
-        value = Utils.formatDate(LocalDate(yy, mm, dd)),
+        value = date?.let { Utils.formatDate(it) } ?: "",
         label = { Text(label) },
         onValueChange = { },
+        isError = isError,
+        supportingText = supportingText,
         trailingIcon = {
             Button(
                 modifier = Modifier.padding(end = LocalSpacing.current.medium),
@@ -89,21 +98,12 @@ fun DatePickerField(
 @Preview
 @Composable
 fun DatePickerFieldPreview() {
-    val cal = Calendar.getInstance()
-    var yy by remember { mutableStateOf(cal.get(Calendar.YEAR)) }
-    var mm by remember { mutableStateOf(cal.get(Calendar.MONTH)) }
-    var dd by remember { mutableStateOf(cal.get(Calendar.DAY_OF_MONTH)) }
+    var date by remember { mutableStateOf(Utils.currentDate) }
     Surface {
         DatePickerField(
             label = "Birthdate",
-            yy = yy,
-            mm = mm,
-            dd = dd,
-            onDateSelected = { y, m, d ->
-                yy = y
-                mm = m
-                dd = d
-            },
+            date = date,
+            onDateSelected = { date = it },
         )
     }
 }
\ No newline at end of file
diff --git a/anastasis/src/main/java/net/taler/anastasis/viewmodels/ReducerViewModel.kt b/anastasis/src/main/java/net/taler/anastasis/viewmodels/ReducerViewModel.kt
index d157707..46be209 100644
--- a/anastasis/src/main/java/net/taler/anastasis/viewmodels/ReducerViewModel.kt
+++ b/anastasis/src/main/java/net/taler/anastasis/viewmodels/ReducerViewModel.kt
@@ -16,7 +16,6 @@
 
 package net.taler.anastasis.viewmodels
 
-import android.util.Log
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
 import dagger.hilt.android.lifecycle.HiltViewModel
@@ -25,6 +24,7 @@ import kotlinx.coroutines.flow.asStateFlow
 import kotlinx.coroutines.launch
 import net.taler.anastasis.Routes
 import net.taler.anastasis.backend.AnastasisReducerApi
+import net.taler.anastasis.backend.TalerErrorInfo
 import net.taler.anastasis.models.BackupStates
 import net.taler.anastasis.models.RecoveryStates
 import net.taler.anastasis.models.ReducerState
@@ -38,14 +38,15 @@ class ReducerViewModel @Inject constructor(): ViewModel() {
 
     private val _reducerState = MutableStateFlow<ReducerState?>(null)
     val reducerState = _reducerState.asStateFlow()
+    private val _reducerError = MutableStateFlow<TalerErrorInfo?>(null)
+    val reducerError = _reducerError.asStateFlow()
     private val _navRoute = MutableStateFlow(Routes.Home.route)
     val navRoute = _navRoute.asStateFlow()
 
     init {
-        reducerManager = ReducerManager(_reducerState, api, viewModelScope)
+        reducerManager = ReducerManager(_reducerState, _reducerError, api, viewModelScope)
         viewModelScope.launch {
             _reducerState.collect {
-                Log.d("ReducerViewModel", it?.toString() ?: "nothing")
                 reducerManager.stopSyncingProviders()
                 _navRoute.value = when (it) {
                     is ReducerState.Backup -> when (it.backupState) {
@@ -72,7 +73,6 @@ class ReducerViewModel @Inject constructor(): ViewModel() {
                         RecoveryStates.ChallengeSolving -> TODO()
                         RecoveryStates.RecoveryFinished -> TODO()
                     }
-                    is ReducerState.Error -> TODO()
                     else -> Routes.Home.route
                 }
             }
@@ -110,4 +110,8 @@ class ReducerViewModel @Inject constructor(): ViewModel() {
     fun goHome() {
         _reducerState.value = null
     }
+
+    fun cleanError() {
+        _reducerError.value = null
+    }
 }
\ No newline at end of file
diff --git a/anastasis/src/main/res/values/strings.xml b/anastasis/src/main/res/values/strings.xml
index cf7054d..b8776c4 100644
--- a/anastasis/src/main/res/values/strings.xml
+++ b/anastasis/src/main/res/values/strings.xml
@@ -15,6 +15,7 @@
     <string name="edit">Edit</string>
     <string name="delete">Delete</string>
     <string name="cancel">Cancel</string>
+    <string name="close">Close</string>
     <string name="menu">Menu</string>
     <string name="country">Country</string>
     <string name="continent">Continent</string>
@@ -24,6 +25,10 @@
     <string name="provided_by">Provided by %1$s</string>
     <string name="disabled">Disabled</string>
     <string name="unknown">Unknown</string>
+    <string name="error">Error</string>
+    <string name="field_empty">This field is required</string>
+    <string name="field_invalid">This field is invalid</string>
+    <string name="field_optional">This field is optional</string>
 
     <!-- Common -->
     <string name="select_continent_title">Where do you live?</string>
@@ -33,6 +38,7 @@
     <!-- Backup -->
     <string name="select_auth_methods_title">Authentication methods</string>
     <string name="review_policies_title">Recovery policies</string>
+    <string name="edit_secret_title">Provide secret to backup</string>
     <string name="add_auth_method_question">Add a question challenge</string>
     <string name="add_auth_method_sms">Add a SMS challenge</string>
     <string name="add_auth_method_email">Add an e-mail challenge</string>
@@ -49,4 +55,7 @@
     <string name="add_challenge">Add challenge</string>
     <string name="add_policy">Add policy</string>
     <string name="edit_policy">Edit policy</string>
+    <string name="secret_name">Secret name</string>
+    <string name="secret_unique">This should be unique</string>
+    <string name="secret_text">Secret text</string>
 </resources>
\ No newline at end of file
diff --git a/taler-kotlin-android/src/main/java/net/taler/common/TalerErrorCode.kt b/taler-kotlin-android/src/main/java/net/taler/common/TalerErrorCode.kt
index dbe59a4..e9968a9 100644
--- a/taler-kotlin-android/src/main/java/net/taler/common/TalerErrorCode.kt
+++ b/taler-kotlin-android/src/main/java/net/taler/common/TalerErrorCode.kt
@@ -3868,6 +3868,12 @@ enum class TalerErrorCode(val code: Int) {
      * (A value of 0 indicates that the error is generated client-side).
      */
     END(9999);
+
+    companion object {
+        fun fromInt(code: Int) = enumValues<TalerErrorCode>().firstOrNull {
+            code == it.code
+        } ?: UNKNOWN
+    }
 }
 
 @OptIn(ExperimentalSerializationApi::class)
@@ -3879,9 +3885,7 @@ object TalerErrorCodeSerializer : KSerializer<TalerErrorCode> {
 
     override fun deserialize(decoder: Decoder): TalerErrorCode {
         val code = decoder.decodeInt()
-        return enumValues<TalerErrorCode>().firstOrNull {
-            code == it.code
-        } ?: TalerErrorCode.UNKNOWN
+        return TalerErrorCode.fromInt(code)
     }
 
     override fun serialize(encoder: Encoder, value: TalerErrorCode) {