Improve UI for regV5 verification code submission.

demo/registration/src/main/java/org/signal/registration/sample/debug/NetworkDebugOverlay.kt

@@ -69,7 +69,7 @@ fun NetworkDebugOverlay(
       onClick = { showDialog = true },
       dragOffset = dragOffset,
       onDrag = { delta -> dragOffset += delta },
-      modifier = Modifier.align(Alignment.BottomEnd)
+      modifier = Modifier.align(Alignment.CenterEnd)
     )
 
     if (showDialog) {

feature/registration/src/main/java/org/signal/registration/screens/phonenumber/PhoneNumberEntryScreen.kt

@@ -5,6 +5,9 @@
 
 package org.signal.registration.screens.phonenumber
 
+import androidx.compose.foundation.Canvas
+import androidx.compose.foundation.background
+import androidx.compose.foundation.clickable
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Column
@@ -14,13 +17,14 @@ import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.height
 import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.rememberScrollState
+import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.foundation.text.KeyboardActions
 import androidx.compose.foundation.text.KeyboardOptions
-import androidx.compose.material3.Button
+import androidx.compose.foundation.verticalScroll
-import androidx.compose.material3.Icon
 import androidx.compose.material3.MaterialTheme
-import androidx.compose.material3.OutlinedButton
 import androidx.compose.material3.OutlinedTextField
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
@@ -31,16 +35,23 @@ import androidx.compose.runtime.remember
 import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.clip
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.graphics.Path
 import androidx.compose.ui.platform.testTag
-import androidx.compose.ui.res.painterResource
+import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.TextRange
 import androidx.compose.ui.text.input.ImeAction
 import androidx.compose.ui.text.input.KeyboardType
 import androidx.compose.ui.text.input.TextFieldValue
 import androidx.compose.ui.unit.dp
+import androidx.compose.ui.unit.sp
+import org.signal.core.ui.compose.Buttons
+import org.signal.core.ui.compose.CircularProgressWrapper
 import org.signal.core.ui.compose.DayNightPreviews
 import org.signal.core.ui.compose.Dialogs
 import org.signal.core.ui.compose.Previews
+import org.signal.registration.R
 import org.signal.registration.screens.phonenumber.PhoneNumberEntryState.OneTimeEvent
 import org.signal.registration.test.TestTags
 
@@ -78,10 +89,6 @@ fun PhoneNumberScreen(
 
   Box(modifier = modifier.fillMaxSize().testTag(TestTags.PHONE_NUMBER_SCREEN)) {
     ScreenContent(state, onEvent)
-
-    if (state.showFullScreenSpinner) {
-      Dialogs.IndeterminateProgressDialog()
-    }
   }
 }
 
@@ -90,23 +97,170 @@ private fun ScreenContent(state: PhoneNumberEntryState, onEvent: (PhoneNumberEnt
   val selectedCountry = state.countryName
   val selectedCountryEmoji = state.countryEmoji
 
-  // Track the phone number text field value with cursor position
+  val scrollState = rememberScrollState()
-  var phoneNumberTextFieldValue by remember { mutableStateOf(TextFieldValue(state.formattedNumber)) }
 
-  // Update the text field value when state.formattedNumber changes, preserving cursor position
+  Column(
-  LaunchedEffect(state.formattedNumber) {
+    modifier = Modifier
-    if (phoneNumberTextFieldValue.text != state.formattedNumber) {
+      .fillMaxSize()
+      .verticalScroll(scrollState)
+  ) {
+    // Toolbar spacer (matching the Toolbar height in the XML)
+    Spacer(modifier = Modifier.height(56.dp))
+
+    // Title - "Phone number"
+    Text(
+      text = stringResource(R.string.RegistrationActivity_phone_number),
+      style = MaterialTheme.typography.headlineMedium,
+      modifier = Modifier
+        .fillMaxWidth()
+        .padding(horizontal = 24.dp)
+    )
+
+    Spacer(modifier = Modifier.height(16.dp))
+
+    // Subtitle - "You will receive a verification code..."
+    Text(
+      text = stringResource(R.string.RegistrationActivity_you_will_receive_a_verification_code),
+      style = MaterialTheme.typography.bodyLarge,
+      color = MaterialTheme.colorScheme.onSurfaceVariant,
+      modifier = Modifier
+        .fillMaxWidth()
+        .padding(horizontal = 24.dp)
+    )
+
+    Spacer(modifier = Modifier.height(36.dp))
+
+    // Country Picker - styled with surfaceVariant background and outline bottom border
+    CountryPicker(
+      emoji = selectedCountryEmoji,
+      country = selectedCountry,
+      onClick = { onEvent(PhoneNumberEntryScreenEvents.CountryPicker) },
+      modifier = Modifier
+        .fillMaxWidth()
+        .padding(horizontal = 24.dp)
+        .testTag(TestTags.PHONE_NUMBER_COUNTRY_PICKER)
+    )
+
+    Spacer(modifier = Modifier.height(16.dp))
+
+    PhoneNumberInputFields(
+      countryCode = state.countryCode,
+      formattedNumber = state.formattedNumber,
+      onCountryCodeChanged = { onEvent(PhoneNumberEntryScreenEvents.CountryCodeChanged(it)) },
+      onPhoneNumberChanged = { onEvent(PhoneNumberEntryScreenEvents.PhoneNumberChanged(it)) },
+      onPhoneNumberSubmitted = { onEvent(PhoneNumberEntryScreenEvents.PhoneNumberSubmitted) },
+      modifier = Modifier
+        .fillMaxWidth()
+        .padding(horizontal = 24.dp)
+    )
+
+    Spacer(modifier = Modifier.weight(1f))
+
+    // Bottom row with the next/spinner button aligned to end
+    Row(
+      modifier = Modifier
+        .fillMaxWidth()
+        .padding(horizontal = 32.dp, vertical = 16.dp),
+      horizontalArrangement = Arrangement.End,
+      verticalAlignment = Alignment.CenterVertically
+    ) {
+      CircularProgressWrapper(
+        isLoading = state.showSpinner
+      ) {
+        Buttons.LargeTonal(
+          onClick = { onEvent(PhoneNumberEntryScreenEvents.PhoneNumberSubmitted) },
+          enabled = state.countryCode.isNotEmpty() && state.nationalNumber.isNotEmpty(),
+          modifier = Modifier.testTag(TestTags.PHONE_NUMBER_NEXT_BUTTON)
+        ) {
+          Text(stringResource(R.string.RegistrationActivity_next))
+        }
+      }
+    }
+  }
+}
+
+/**
+ * Country picker row styled to match the XML layout:
+ * - surfaceVariant background with outline bottom border
+ * - Rounded top corners (8dp outline, 4dp inner)
+ * - Country emoji, country name, and dropdown triangle
+ */
+@Composable
+private fun CountryPicker(
+  emoji: String,
+  country: String,
+  onClick: () -> Unit,
+  modifier: Modifier = Modifier
+) {
+  Box(
+    modifier = modifier
+      .clip(RoundedCornerShape(topStart = 8.dp, topEnd = 8.dp))
+      .background(MaterialTheme.colorScheme.outline)
+      .padding(bottom = 1.dp)
+      .background(
+        color = MaterialTheme.colorScheme.surfaceVariant,
+        shape = RoundedCornerShape(topStart = 4.dp, topEnd = 4.dp)
+      )
+      .clickable(onClick = onClick)
+      .height(56.dp)
+  ) {
+    Row(
+      modifier = Modifier
+        .fillMaxSize()
+        .padding(start = 16.dp, end = 12.dp),
+      verticalAlignment = Alignment.CenterVertically
+    ) {
+      Text(
+        text = emoji,
+        fontSize = 24.sp
+      )
+
+      Spacer(modifier = Modifier.width(16.dp))
+
+      Text(
+        text = country,
+        style = MaterialTheme.typography.bodyLarge,
+        color = MaterialTheme.colorScheme.onSurfaceVariant,
+        modifier = Modifier.weight(1f)
+      )
+
+      DropdownTriangle(
+        tint = MaterialTheme.colorScheme.onSurfaceVariant,
+        modifier = Modifier.size(24.dp)
+      )
+    }
+  }
+}
+
+/**
+ * Phone number input fields containing the country code and phone number text fields.
+ * Handles cursor position preservation when the formatted number changes.
+ */
+@Composable
+private fun PhoneNumberInputFields(
+  countryCode: String,
+  formattedNumber: String,
+  onCountryCodeChanged: (String) -> Unit,
+  onPhoneNumberChanged: (String) -> Unit,
+  onPhoneNumberSubmitted: () -> Unit,
+  modifier: Modifier = Modifier
+) {
+  // Track the phone number text field value with cursor position
+  var phoneNumberTextFieldValue by remember { mutableStateOf(TextFieldValue(formattedNumber)) }
+
+  // Update the text field value when formattedNumber changes, preserving cursor position
+  LaunchedEffect(formattedNumber) {
+    if (phoneNumberTextFieldValue.text != formattedNumber) {
       // Calculate cursor position: count digits before cursor in old text,
       // then find position with same digit count in new text
       val oldText = phoneNumberTextFieldValue.text
       val oldCursorPos = phoneNumberTextFieldValue.selection.end
       val digitsBeforeCursor = oldText.take(oldCursorPos).count { it.isDigit() }
 
-      val newText = state.formattedNumber
       var digitCount = 0
-      var newCursorPos = newText.length
+      var newCursorPos = formattedNumber.length
-      for (i in newText.indices) {
+      for (i in formattedNumber.indices) {
-        if (newText[i].isDigit()) {
+        if (formattedNumber[i].isDigit()) {
           digitCount++
         }
         if (digitCount >= digitsBeforeCursor) {
@@ -116,140 +270,92 @@ private fun ScreenContent(state: PhoneNumberEntryState, onEvent: (PhoneNumberEnt
       }
 
       phoneNumberTextFieldValue = TextFieldValue(
-        text = newText,
+        text = formattedNumber,
         selection = TextRange(newCursorPos)
       )
     }
   }
 
-  Column(
+  Row(
-    modifier = Modifier
+    modifier = modifier,
-      .fillMaxSize()
+    horizontalArrangement = Arrangement.Start,
-      .padding(24.dp),
+    verticalAlignment = Alignment.Bottom
-    horizontalAlignment = Alignment.Start
   ) {
-    // Title
+    // Country code field
-    Text(
+    OutlinedTextField(
-      text = "Phone number",
+      value = countryCode,
-      style = MaterialTheme.typography.headlineMedium,
+      onValueChange = onCountryCodeChanged,
-      modifier = Modifier.fillMaxWidth()
-    )
-
-    Spacer(modifier = Modifier.height(16.dp))
-
-    // Subtitle
-    Text(
-      text = "You will receive a verification code",
-      style = MaterialTheme.typography.bodyLarge,
-      color = MaterialTheme.colorScheme.onSurfaceVariant,
-      modifier = Modifier.fillMaxWidth()
-    )
-
-    Spacer(modifier = Modifier.height(36.dp))
-
-    // Country Picker Button
-    OutlinedButton(
-      onClick = {
-        onEvent(PhoneNumberEntryScreenEvents.CountryPicker)
-      },
       modifier = Modifier
-        .fillMaxWidth()
+        .width(76.dp)
-        .height(56.dp)
+        .testTag(TestTags.PHONE_NUMBER_COUNTRY_CODE_FIELD),
-        .testTag(TestTags.PHONE_NUMBER_COUNTRY_PICKER)
+      prefix = {
-    ) {
-      Row(
-        modifier = Modifier.fillMaxWidth(),
-        horizontalArrangement = Arrangement.Start,
-        verticalAlignment = Alignment.CenterVertically
-      ) {
         Text(
-          text = selectedCountryEmoji,
+          text = "+",
-          style = MaterialTheme.typography.headlineSmall
-        )
-        Spacer(modifier = Modifier.width(16.dp))
-        Text(
-          text = selectedCountry,
           style = MaterialTheme.typography.bodyLarge,
-          color = MaterialTheme.colorScheme.onSurfaceVariant,
+          color = MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 0.6f)
-          modifier = Modifier.weight(1f)
         )
-        Icon(
+      },
-          painter = painterResource(android.R.drawable.arrow_down_float),
+      keyboardOptions = KeyboardOptions(
-          contentDescription = "Select country",
+        keyboardType = KeyboardType.Number,
-          tint = MaterialTheme.colorScheme.onSurfaceVariant
+        imeAction = ImeAction.Done
-        )
+      ),
-      }
+      singleLine = true,
-    }
+      textStyle = MaterialTheme.typography.bodyLarge.copy(
-
+        color = MaterialTheme.colorScheme.onSurfaceVariant
-    Spacer(modifier = Modifier.height(20.dp))
-
-    // Phone number input fields
-    Row(
-      modifier = Modifier.fillMaxWidth(),
-      horizontalArrangement = Arrangement.spacedBy(20.dp)
-    ) {
-      // Country code field
-      OutlinedTextField(
-        value = state.countryCode,
-        onValueChange = { onEvent(PhoneNumberEntryScreenEvents.CountryCodeChanged(it)) },
-        modifier = Modifier
-          .width(76.dp)
-          .testTag(TestTags.PHONE_NUMBER_COUNTRY_CODE_FIELD),
-        leadingIcon = {
-          Text(
-            text = "+",
-            style = MaterialTheme.typography.bodyLarge,
-            color = MaterialTheme.colorScheme.onSurfaceVariant
-          )
-        },
-        keyboardOptions = KeyboardOptions(
-          keyboardType = KeyboardType.Number,
-          imeAction = ImeAction.Next
-        ),
-        singleLine = true
       )
+    )
 
-      // Phone number field
+    Spacer(modifier = Modifier.width(20.dp))
-      OutlinedTextField(
-        value = phoneNumberTextFieldValue,
-        onValueChange = { newValue ->
-          phoneNumberTextFieldValue = newValue
-          onEvent(PhoneNumberEntryScreenEvents.PhoneNumberChanged(newValue.text))
-        },
-        modifier = Modifier
-          .weight(1f)
-          .testTag(TestTags.PHONE_NUMBER_PHONE_FIELD),
-        placeholder = {
-          Text("Phone number")
-        },
-        keyboardOptions = KeyboardOptions(
-          keyboardType = KeyboardType.Phone,
-          imeAction = ImeAction.Done
-        ),
-        keyboardActions = KeyboardActions(
-          onDone = {
-            onEvent(PhoneNumberEntryScreenEvents.PhoneNumberSubmitted)
-          }
-        ),
-        singleLine = true
-      )
-    }
 
-    Spacer(modifier = Modifier.weight(1f))
+    // Phone number field
-
+    OutlinedTextField(
-    // Next button
+      value = phoneNumberTextFieldValue,
-    Button(
+      onValueChange = { newValue ->
-      onClick = {
+        phoneNumberTextFieldValue = newValue
-        onEvent(PhoneNumberEntryScreenEvents.PhoneNumberSubmitted)
+        onPhoneNumberChanged(newValue.text)
       },
       modifier = Modifier
-        .fillMaxWidth()
+        .weight(1f)
-        .height(56.dp)
+        .testTag(TestTags.PHONE_NUMBER_PHONE_FIELD),
-        .testTag(TestTags.PHONE_NUMBER_NEXT_BUTTON),
+      label = {
-      enabled = state.countryCode.isNotEmpty() && state.nationalNumber.isNotEmpty()
+        Text(stringResource(R.string.RegistrationActivity_phone_number_description))
-    ) {
+      },
-      Text("Next")
+      keyboardOptions = KeyboardOptions(
+        keyboardType = KeyboardType.Phone,
+        imeAction = ImeAction.Done
+      ),
+      keyboardActions = KeyboardActions(
+        onDone = { onPhoneNumberSubmitted() }
+      ),
+      singleLine = true,
+      textStyle = MaterialTheme.typography.bodyLarge.copy(
+        color = MaterialTheme.colorScheme.onSurface
+      )
+    )
+  }
+}
+
+/**
+ * Simple dropdown triangle icon matching the symbol_dropdown_triangle_24 vector drawable.
+ */
+@Composable
+private fun DropdownTriangle(
+  tint: Color,
+  modifier: Modifier = Modifier
+) {
+  Canvas(modifier = modifier) {
+    val w = size.width
+    val h = size.height
+    val path = Path().apply {
+      // Triangle pointing down, centered in the 18x24 viewport
+      val scaleX = w / 18f
+      val scaleY = h / 24f
+      moveTo(5.2f * scaleX, 9.5f * scaleY)
+      lineTo(12.8f * scaleX, 9.5f * scaleY)
+      lineTo(9f * scaleX, 14.95f * scaleY)
+      close()
     }
+    drawPath(path, tint)
   }
 }
 
@@ -269,7 +375,7 @@ private fun PhoneNumberScreenPreview() {
 private fun PhoneNumberScreenSpinnerPreview() {
   Previews.Preview {
     PhoneNumberScreen(
-      state = PhoneNumberEntryState(showFullScreenSpinner = true),
+      state = PhoneNumberEntryState(showSpinner = true),
       onEvent = {}
     )
   }

feature/registration/src/main/java/org/signal/registration/screens/phonenumber/PhoneNumberEntryState.kt

@@ -19,7 +19,7 @@ data class PhoneNumberEntryState(
   val formattedNumber: String = "",
   val sessionE164: String? = null,
   val sessionMetadata: SessionMetadata? = null,
-  val showFullScreenSpinner: Boolean = false,
+  val showSpinner: Boolean = false,
   val oneTimeEvent: OneTimeEvent? = null,
   val preExistingRegistrationData: PreExistingRegistrationData? = null,
   val restoredSvrCredentials: List<NetworkController.SvrCredentials> = emptyList()

feature/registration/src/main/java/org/signal/registration/screens/phonenumber/PhoneNumberEntryViewModel.kt

@@ -46,7 +46,7 @@ class PhoneNumberEntryViewModel(
   val state = _state
     .combine(parentState) { state, parentState -> applyParentState(state, parentState) }
     .onEach { Log.d(TAG, "[State] $it") }
-    .stateIn(viewModelScope, SharingStarted.Eagerly, PhoneNumberEntryState())
+    .stateIn(viewModelScope, SharingStarted.WhileSubscribed(5000), PhoneNumberEntryState())
 
   init {
     viewModelScope.launch {
@@ -78,10 +78,10 @@ class PhoneNumberEntryViewModel(
         stateEmitter(applyPhoneNumberChanged(state, event.value))
       }
       is PhoneNumberEntryScreenEvents.PhoneNumberSubmitted -> {
-        var localState = state.copy(showFullScreenSpinner = true)
+        var localState = state.copy(showSpinner = true)
         stateEmitter(localState)
         localState = applyPhoneNumberSubmitted(localState, parentEventEmitter)
-        stateEmitter(localState.copy(showFullScreenSpinner = false))
+        stateEmitter(localState.copy(showSpinner = false))
       }
       is PhoneNumberEntryScreenEvents.CountryPicker -> {
         state.also { parentEventEmitter.navigateTo(RegistrationRoute.CountryCodePicker) }

feature/registration/src/main/java/org/signal/registration/screens/pincreation/PinCreationViewModel.kt

@@ -48,7 +48,7 @@ class PinCreationViewModel(
   val state: StateFlow<PinCreationState> = _state
     .combine(parentState) { state, parentState -> applyParentState(state, parentState) }
     .onEach { Log.d(TAG, "[State] $it") }
-    .stateIn(viewModelScope, SharingStarted.Eagerly, PinCreationState(inputLabel = "PIN must be at least 4 digits"))
+    .stateIn(viewModelScope, SharingStarted.WhileSubscribed(5000), PinCreationState(inputLabel = "PIN must be at least 4 digits"))
 
   fun onEvent(event: PinCreationScreenEvents) {
     viewModelScope.launch {

feature/registration/src/main/java/org/signal/registration/screens/pinentry/PinEntryForRegistrationLockViewModel.kt

@@ -50,7 +50,7 @@ class PinEntryForRegistrationLockViewModel(
 
   val state: StateFlow<PinEntryState> = _state
     .onEach { Log.d(TAG, "[State] $it") }
-    .stateIn(viewModelScope, SharingStarted.Eagerly, PinEntryState(showNeedHelp = true))
+    .stateIn(viewModelScope, SharingStarted.WhileSubscribed(5000), PinEntryState(showNeedHelp = true))
 
   fun onEvent(event: PinEntryScreenEvents) {
     viewModelScope.launch {

feature/registration/src/main/java/org/signal/registration/screens/pinentry/PinEntryForSmsBypassViewModel.kt

@@ -54,7 +54,7 @@ class PinEntryForSmsBypassViewModel(
   val state: StateFlow<PinEntryState> = _state
     .combine(parentState) { state, parentState -> applyParentState(state, parentState) }
     .onEach { Log.d(TAG, "[State] $it") }
-    .stateIn(viewModelScope, SharingStarted.Eagerly, PinEntryState(showNeedHelp = true))
+    .stateIn(viewModelScope, SharingStarted.WhileSubscribed(5000), PinEntryState(showNeedHelp = true))
 
   fun onEvent(event: PinEntryScreenEvents) {
     viewModelScope.launch {

feature/registration/src/main/java/org/signal/registration/screens/pinentry/PinEntryForSvrRestoreViewModel.kt

@@ -47,7 +47,7 @@ class PinEntryForSvrRestoreViewModel(
 
   val state: StateFlow<PinEntryState> = _state
     .onEach { Log.d(TAG, "[State] $it") }
-    .stateIn(viewModelScope, SharingStarted.Eagerly, PinEntryState(showNeedHelp = true))
+    .stateIn(viewModelScope, SharingStarted.WhileSubscribed(5000), PinEntryState(showNeedHelp = true))
 
   fun onEvent(event: PinEntryScreenEvents) {
     viewModelScope.launch {

feature/registration/src/main/java/org/signal/registration/screens/verificationcode/VerificationCodeScreen.kt

@@ -6,6 +6,7 @@
 package org.signal.registration.screens.verificationcode
 
 import androidx.compose.foundation.layout.Arrangement
+import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.Row
 import androidx.compose.foundation.layout.Spacer
@@ -13,10 +14,19 @@ import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.height
 import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.layout.width
+import androidx.compose.foundation.layout.wrapContentWidth
+import androidx.compose.foundation.rememberScrollState
 import androidx.compose.foundation.text.KeyboardOptions
+import androidx.compose.foundation.verticalScroll
+import androidx.compose.material3.CircularProgressIndicator
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.OutlinedTextField
+import androidx.compose.material3.OutlinedTextFieldDefaults
+import androidx.compose.material3.Scaffold
+import androidx.compose.material3.SnackbarHost
+import androidx.compose.material3.SnackbarHostState
 import androidx.compose.material3.Text
 import androidx.compose.material3.TextButton
 import androidx.compose.runtime.Composable
@@ -29,17 +39,27 @@ import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.focus.FocusRequester
 import androidx.compose.ui.focus.focusRequester
+import androidx.compose.ui.input.key.Key
+import androidx.compose.ui.input.key.KeyEventType
+import androidx.compose.ui.input.key.key
+import androidx.compose.ui.input.key.onKeyEvent
+import androidx.compose.ui.input.key.type
 import androidx.compose.ui.platform.testTag
+import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.input.KeyboardType
 import androidx.compose.ui.text.style.TextAlign
 import androidx.compose.ui.unit.dp
+import kotlinx.coroutines.delay
 import org.signal.core.ui.compose.DayNightPreviews
 import org.signal.core.ui.compose.Previews
+import org.signal.registration.R
 import org.signal.registration.test.TestTags
+import kotlin.time.Duration.Companion.seconds
 
 /**
  * Verification code entry screen for the registration flow.
- * Displays a 6-digit code input in XXX-XXX format.
+ * Displays a 6-digit code input in XXX-XXX format with countdown buttons
+ * for resend SMS and call me actions.
  */
 @Composable
 fun VerificationCodeScreen(
@@ -49,177 +69,372 @@ fun VerificationCodeScreen(
 ) {
   var digits by remember { mutableStateOf(List(6) { "" }) }
   val focusRequesters = remember { List(6) { FocusRequester() } }
+  val scrollState = rememberScrollState()
+  val snackbarHostState = remember { SnackbarHostState() }
+
+  // Preload error strings for use in LaunchedEffect
+  val incorrectCodeMsg = stringResource(R.string.VerificationCodeScreen__incorrect_code)
+  val networkErrorMsg = stringResource(R.string.VerificationCodeScreen__network_error)
+  val unknownErrorMsg = stringResource(R.string.VerificationCodeScreen__an_unexpected_error_occurred)
+  val smsProviderErrorMsg = stringResource(R.string.VerificationCodeScreen__sms_provider_error)
+  val transportErrorMsg = stringResource(R.string.VerificationCodeScreen__could_not_send_code_via_selected_method)
+  val registrationErrorMsg = stringResource(R.string.VerificationCodeScreen__registration_error)
+  // Preformat the rate-limited message template
+  val rateLimitedEvent = state.oneTimeEvent as? VerificationCodeState.OneTimeEvent.RateLimited
+  val rateLimitedMsg = if (rateLimitedEvent != null) {
+    stringResource(R.string.VerificationCodeScreen__too_many_attempts_try_again_in_s, rateLimitedEvent.retryAfter.toString())
+  } else {
+    ""
+  }
+
+  // Countdown timer effect - emits CountdownTick every second while timers are active
+  LaunchedEffect(state.rateLimits) {
+    if (state.rateLimits.smsResendTimeRemaining > 0.seconds || state.rateLimits.callRequestTimeRemaining > 0.seconds) {
+      while (true) {
+        delay(1000)
+        onEvent(VerificationCodeScreenEvents.CountdownTick)
+      }
+    }
+  }
 
   // Auto-submit when all digits are entered
   LaunchedEffect(digits) {
-    if (digits.all { it.isNotEmpty() }) {
+    if (digits.all { it.isNotEmpty() } && !state.isSubmittingCode) {
       val code = digits.joinToString("")
       onEvent(VerificationCodeScreenEvents.CodeEntered(code))
     }
   }
 
+  // Handle one-time events — handle first, then consume
   LaunchedEffect(state.oneTimeEvent) {
+    val event = state.oneTimeEvent ?: return@LaunchedEffect
+
+    when (event) {
+      VerificationCodeState.OneTimeEvent.IncorrectVerificationCode -> {
+        digits = List(6) { "" }
+        focusRequesters[0].requestFocus()
+        snackbarHostState.showSnackbar(incorrectCodeMsg)
+      }
+      VerificationCodeState.OneTimeEvent.NetworkError -> {
+        snackbarHostState.showSnackbar(networkErrorMsg)
+      }
+      is VerificationCodeState.OneTimeEvent.RateLimited -> {
+        snackbarHostState.showSnackbar(rateLimitedMsg)
+      }
+      VerificationCodeState.OneTimeEvent.ThirdPartyError -> {
+        snackbarHostState.showSnackbar(smsProviderErrorMsg)
+      }
+      VerificationCodeState.OneTimeEvent.CouldNotRequestCodeWithSelectedTransport -> {
+        snackbarHostState.showSnackbar(transportErrorMsg)
+      }
+      VerificationCodeState.OneTimeEvent.UnknownError -> {
+        snackbarHostState.showSnackbar(unknownErrorMsg)
+      }
+      VerificationCodeState.OneTimeEvent.RegistrationError -> {
+        snackbarHostState.showSnackbar(registrationErrorMsg)
+      }
+    }
+
     onEvent(VerificationCodeScreenEvents.ConsumeInnerOneTimeEvent)
-
-    when (state.oneTimeEvent) {
-      VerificationCodeState.OneTimeEvent.CouldNotRequestCodeWithSelectedTransport -> { }
-      VerificationCodeState.OneTimeEvent.IncorrectVerificationCode -> { }
-      VerificationCodeState.OneTimeEvent.NetworkError -> { }
-      is VerificationCodeState.OneTimeEvent.RateLimited -> { }
-      VerificationCodeState.OneTimeEvent.ThirdPartyError -> { }
-      VerificationCodeState.OneTimeEvent.UnknownError -> { }
-      VerificationCodeState.OneTimeEvent.RegistrationError -> { }
-      null -> { }
-    }
-  }
-
-  Column(
-    modifier = modifier
-      .fillMaxSize()
-      .padding(24.dp),
-    horizontalAlignment = Alignment.CenterHorizontally,
-    verticalArrangement = Arrangement.Top
-  ) {
-    Spacer(modifier = Modifier.height(48.dp))
-
-    Text(
-      text = "Enter verification code",
-      style = MaterialTheme.typography.headlineMedium,
-      textAlign = TextAlign.Center
-    )
-
-    Spacer(modifier = Modifier.height(16.dp))
-
-    Text(
-      text = "Enter the code we sent to ${state.e164}",
-      style = MaterialTheme.typography.bodyMedium,
-      textAlign = TextAlign.Center,
-      color = MaterialTheme.colorScheme.onSurfaceVariant
-    )
-
-    Spacer(modifier = Modifier.height(32.dp))
-
-    // Code input fields - XXX-XXX format
-    Row(
-      modifier = Modifier
-        .fillMaxWidth()
-        .testTag(TestTags.VERIFICATION_CODE_INPUT),
-      horizontalArrangement = Arrangement.Center,
-      verticalAlignment = Alignment.CenterVertically
-    ) {
-      // First three digits
-      for (i in 0..2) {
-        DigitField(
-          value = digits[i],
-          onValueChange = { newValue ->
-            if (newValue.length <= 1 && (newValue.isEmpty() || newValue.all { it.isDigit() })) {
-              digits = digits.toMutableList().apply { this[i] = newValue }
-              if (newValue.isNotEmpty() && i < 5) {
-                focusRequesters[i + 1].requestFocus()
-              }
-            }
-          },
-          focusRequester = focusRequesters[i],
-          testTag = when (i) {
-            0 -> TestTags.VERIFICATION_CODE_DIGIT_0
-            1 -> TestTags.VERIFICATION_CODE_DIGIT_1
-            else -> TestTags.VERIFICATION_CODE_DIGIT_2
-          }
-        )
-        if (i < 2) {
-          Spacer(modifier = Modifier.width(4.dp))
-        }
-      }
-
-      // Separator
-      Text(
-        text = "-",
-        style = MaterialTheme.typography.headlineMedium,
-        modifier = Modifier.padding(horizontal = 8.dp)
-      )
-
-      // Last three digits
-      for (i in 3..5) {
-        if (i > 3) {
-          Spacer(modifier = Modifier.width(4.dp))
-        }
-        DigitField(
-          value = digits[i],
-          onValueChange = { newValue ->
-            if (newValue.length <= 1 && (newValue.isEmpty() || newValue.all { it.isDigit() })) {
-              digits = digits.toMutableList().apply { this[i] = newValue }
-              if (newValue.isNotEmpty() && i < 5) {
-                focusRequesters[i + 1].requestFocus()
-              }
-            }
-          },
-          focusRequester = focusRequesters[i],
-          testTag = when (i) {
-            3 -> TestTags.VERIFICATION_CODE_DIGIT_3
-            4 -> TestTags.VERIFICATION_CODE_DIGIT_4
-            else -> TestTags.VERIFICATION_CODE_DIGIT_5
-          }
-        )
-      }
-    }
-
-    Spacer(modifier = Modifier.height(32.dp))
-
-    TextButton(
-      onClick = { onEvent(VerificationCodeScreenEvents.WrongNumber) },
-      modifier = Modifier.testTag(TestTags.VERIFICATION_CODE_WRONG_NUMBER_BUTTON)
-    ) {
-      Text("Wrong number?")
-    }
-
-    Spacer(modifier = Modifier.weight(1f))
-
-    TextButton(
-      onClick = { onEvent(VerificationCodeScreenEvents.ResendSms) },
-      modifier = Modifier
-        .fillMaxWidth()
-        .testTag(TestTags.VERIFICATION_CODE_RESEND_SMS_BUTTON)
-    ) {
-      Text("Resend SMS")
-    }
-
-    TextButton(
-      onClick = { onEvent(VerificationCodeScreenEvents.CallMe) },
-      modifier = Modifier
-        .fillMaxWidth()
-        .testTag(TestTags.VERIFICATION_CODE_CALL_ME_BUTTON)
-    ) {
-      Text("Call me instead")
-    }
   }
 
   // Auto-focus first field on initial composition
   LaunchedEffect(Unit) {
     focusRequesters[0].requestFocus()
   }
+
+  Scaffold(
+    snackbarHost = { SnackbarHost(snackbarHostState) },
+    modifier = modifier
+  ) { innerPadding ->
+    Column(
+      modifier = Modifier
+        .fillMaxSize()
+        .padding(innerPadding)
+        .verticalScroll(scrollState)
+        .padding(horizontal = 24.dp),
+      horizontalAlignment = Alignment.CenterHorizontally
+    ) {
+      Spacer(modifier = Modifier.height(40.dp))
+
+      // Header
+      Text(
+        text = stringResource(R.string.VerificationCodeScreen__verification_code),
+        style = MaterialTheme.typography.headlineMedium,
+        modifier = Modifier
+          .fillMaxWidth()
+          .wrapContentWidth(Alignment.Start)
+      )
+
+      Spacer(modifier = Modifier.height(16.dp))
+
+      // Subheader with phone number
+      Text(
+        text = stringResource(R.string.VerificationCodeScreen__enter_the_code_we_sent_to_s, state.e164),
+        style = MaterialTheme.typography.bodyMedium,
+        color = MaterialTheme.colorScheme.onSurfaceVariant,
+        modifier = Modifier
+          .fillMaxWidth()
+          .wrapContentWidth(Alignment.Start)
+      )
+
+      Spacer(modifier = Modifier.height(8.dp))
+
+      // Wrong number button - aligned to start like in XML
+      TextButton(
+        onClick = { onEvent(VerificationCodeScreenEvents.WrongNumber) },
+        modifier = Modifier
+          .fillMaxWidth()
+          .wrapContentWidth(Alignment.Start)
+          .testTag(TestTags.VERIFICATION_CODE_WRONG_NUMBER_BUTTON)
+      ) {
+        Text(
+          text = stringResource(R.string.VerificationCodeScreen__wrong_number),
+          color = MaterialTheme.colorScheme.primary
+        )
+      }
+
+      Spacer(modifier = Modifier.height(32.dp))
+
+      // Code input with spinner overlay when submitting
+      Box(
+        modifier = Modifier.fillMaxWidth(),
+        contentAlignment = Alignment.Center
+      ) {
+        // Code input fields - XXX-XXX format
+        Row(
+          modifier = Modifier
+            .fillMaxWidth()
+            .testTag(TestTags.VERIFICATION_CODE_INPUT),
+          horizontalArrangement = Arrangement.Center,
+          verticalAlignment = Alignment.CenterVertically
+        ) {
+          // First three digits
+          for (i in 0..2) {
+            DigitField(
+              value = digits[i],
+              onValueChange = { newValue, isBackspace ->
+                handleDigitChange(
+                  index = i,
+                  newValue = newValue,
+                  isBackspace = isBackspace,
+                  digits = digits,
+                  focusRequesters = focusRequesters,
+                  onDigitsChanged = { digits = it }
+                )
+              },
+              focusRequester = focusRequesters[i],
+              testTag = when (i) {
+                0 -> TestTags.VERIFICATION_CODE_DIGIT_0
+                1 -> TestTags.VERIFICATION_CODE_DIGIT_1
+                else -> TestTags.VERIFICATION_CODE_DIGIT_2
+              },
+              enabled = !state.isSubmittingCode
+            )
+            if (i < 2) {
+              Spacer(modifier = Modifier.width(4.dp))
+            }
+          }
+
+          // Separator
+          Text(
+            text = "-",
+            style = MaterialTheme.typography.headlineMedium,
+            modifier = Modifier.padding(horizontal = 8.dp),
+            color = if (state.isSubmittingCode) MaterialTheme.colorScheme.onSurface.copy(alpha = 0.38f) else MaterialTheme.colorScheme.onSurface
+          )
+
+          // Last three digits
+          for (i in 3..5) {
+            if (i > 3) {
+              Spacer(modifier = Modifier.width(4.dp))
+            }
+            DigitField(
+              value = digits[i],
+              onValueChange = { newValue, isBackspace ->
+                handleDigitChange(
+                  index = i,
+                  newValue = newValue,
+                  isBackspace = isBackspace,
+                  digits = digits,
+                  focusRequesters = focusRequesters,
+                  onDigitsChanged = { digits = it }
+                )
+              },
+              focusRequester = focusRequesters[i],
+              testTag = when (i) {
+                3 -> TestTags.VERIFICATION_CODE_DIGIT_3
+                4 -> TestTags.VERIFICATION_CODE_DIGIT_4
+                else -> TestTags.VERIFICATION_CODE_DIGIT_5
+              },
+              enabled = !state.isSubmittingCode
+            )
+          }
+        }
+
+        // Loading spinner overlay
+        if (state.isSubmittingCode) {
+          CircularProgressIndicator(
+            modifier = Modifier.size(48.dp)
+          )
+        }
+      }
+
+      Spacer(modifier = Modifier.height(32.dp))
+
+      // Having trouble button - shown after 3 incorrect code attempts (matching old behavior)
+      if (state.shouldShowHavingTrouble()) {
+        TextButton(
+          onClick = { onEvent(VerificationCodeScreenEvents.HavingTrouble) },
+          modifier = Modifier
+            .fillMaxWidth()
+            .wrapContentWidth(Alignment.CenterHorizontally)
+            .testTag(TestTags.VERIFICATION_CODE_HAVING_TROUBLE_BUTTON)
+        ) {
+          Text(
+            text = stringResource(R.string.VerificationCodeScreen__having_trouble),
+            color = MaterialTheme.colorScheme.primary
+          )
+        }
+      }
+
+      Spacer(modifier = Modifier.weight(1f))
+
+      // Bottom buttons - Resend SMS and Call Me side by side
+      Row(
+        modifier = Modifier
+          .fillMaxWidth()
+          .padding(bottom = 32.dp),
+        horizontalArrangement = Arrangement.SpaceBetween,
+        verticalAlignment = Alignment.Bottom
+      ) {
+        // Resend SMS button with countdown — fits on one line if space allows, wraps if not
+        val canResendSms = state.canResendSms()
+        val disabledColor = MaterialTheme.colorScheme.onSurface.copy(alpha = 0.38f)
+        TextButton(
+          onClick = { onEvent(VerificationCodeScreenEvents.ResendSms) },
+          enabled = canResendSms,
+          modifier = Modifier
+            .weight(1f)
+            .testTag(TestTags.VERIFICATION_CODE_RESEND_SMS_BUTTON)
+        ) {
+          Text(
+            text = if (canResendSms) {
+              stringResource(R.string.VerificationCodeScreen__resend_code)
+            } else {
+              val totalSeconds = state.rateLimits.smsResendTimeRemaining.inWholeSeconds.toInt()
+              val minutes = totalSeconds / 60
+              val seconds = totalSeconds % 60
+              stringResource(R.string.VerificationCodeScreen__resend_code) + " " +
+                stringResource(R.string.VerificationCodeScreen__countdown_format, minutes, seconds)
+            },
+            color = if (canResendSms) MaterialTheme.colorScheme.primary else disabledColor,
+            textAlign = TextAlign.Center
+          )
+        }
+
+        Spacer(modifier = Modifier.width(8.dp))
+
+        // Call Me button with inline countdown
+        val canRequestCall = state.canRequestCall()
+        TextButton(
+          onClick = { onEvent(VerificationCodeScreenEvents.CallMe) },
+          enabled = canRequestCall,
+          modifier = Modifier
+            .weight(1f)
+            .testTag(TestTags.VERIFICATION_CODE_CALL_ME_BUTTON)
+        ) {
+          Text(
+            text = if (canRequestCall) {
+              stringResource(R.string.VerificationCodeScreen__call_me_instead)
+            } else {
+              val totalSeconds = state.rateLimits.callRequestTimeRemaining.inWholeSeconds.toInt()
+              val minutes = totalSeconds / 60
+              val seconds = totalSeconds % 60
+              stringResource(R.string.VerificationCodeScreen__call_me_available_in, minutes, seconds)
+            },
+            color = if (canRequestCall) MaterialTheme.colorScheme.primary else disabledColor,
+            textAlign = TextAlign.Center
+          )
+        }
+      }
+    }
+  }
 }
 
 /**
- * Individual digit input field
+ * Handles digit input changes including navigation between fields and backspace handling.
+ */
+private fun handleDigitChange(
+  index: Int,
+  newValue: String,
+  isBackspace: Boolean,
+  digits: List<String>,
+  focusRequesters: List<FocusRequester>,
+  onDigitsChanged: (List<String>) -> Unit
+) {
+  when {
+    // Handle backspace on empty field - move to previous field
+    isBackspace && newValue.isEmpty() && index > 0 -> {
+      val newDigits = digits.toMutableList().apply { this[index] = "" }
+      onDigitsChanged(newDigits)
+      focusRequesters[index - 1].requestFocus()
+    }
+    // Handle new digit input
+    newValue.length <= 1 && (newValue.isEmpty() || newValue.all { it.isDigit() }) -> {
+      val newDigits = digits.toMutableList().apply { this[index] = newValue }
+      onDigitsChanged(newDigits)
+      // Move to next field if digit entered and not last field
+      if (newValue.isNotEmpty() && index < 5) {
+        focusRequesters[index + 1].requestFocus()
+      }
+    }
+  }
+}
+
+/**
+ * Individual digit input field with backspace handling.
  */
 @Composable
 private fun DigitField(
   value: String,
-  onValueChange: (String) -> Unit,
+  onValueChange: (String, Boolean) -> Unit,
   focusRequester: FocusRequester,
   testTag: String,
-  modifier: Modifier = Modifier
+  modifier: Modifier = Modifier,
+  enabled: Boolean = true
 ) {
   OutlinedTextField(
     value = value,
-    onValueChange = onValueChange,
+    onValueChange = { newValue ->
+      // Determine if this is a backspace (new value is empty and old value was not)
+      val isBackspace = newValue.isEmpty() && value.isNotEmpty()
+      onValueChange(newValue, isBackspace)
+    },
     modifier = modifier
-      .width(44.dp)
+      .width(48.dp)
       .focusRequester(focusRequester)
-      .testTag(testTag),
+      .testTag(testTag)
+      .onKeyEvent { keyEvent ->
+        // Handle hardware backspace key when field is empty
+        if (keyEvent.type == KeyEventType.KeyUp &&
+          (keyEvent.key == Key.Backspace || keyEvent.key == Key.Delete) &&
+          value.isEmpty()
+        ) {
+          onValueChange("", true)
+          true
+        } else {
+          false
+        }
+      },
     textStyle = MaterialTheme.typography.titleLarge.copy(textAlign = TextAlign.Center),
     singleLine = true,
-    keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Number)
+    keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Number),
+    enabled = enabled,
+    colors = OutlinedTextFieldDefaults.colors(
+      disabledTextColor = MaterialTheme.colorScheme.onSurface.copy(alpha = 0.38f),
+      disabledBorderColor = MaterialTheme.colorScheme.onSurface.copy(alpha = 0.12f)
+    )
   )
 }
 
@@ -228,7 +443,40 @@ private fun DigitField(
 private fun VerificationCodeScreenPreview() {
   Previews.Preview {
     VerificationCodeScreen(
-      state = VerificationCodeState(),
+      state = VerificationCodeState(
+        e164 = "+1 555-123-4567"
+      ),
+      onEvent = {}
+    )
+  }
+}
+
+@DayNightPreviews
+@Composable
+private fun VerificationCodeScreenWithCountdownPreview() {
+  Previews.Preview {
+    VerificationCodeScreen(
+      state = VerificationCodeState(
+        e164 = "+1 555-123-4567",
+        rateLimits = SmsAndCallRateLimits(
+          smsResendTimeRemaining = 45.seconds,
+          callRequestTimeRemaining = 64.seconds
+        )
+      ),
+      onEvent = {}
+    )
+  }
+}
+
+@DayNightPreviews
+@Composable
+private fun VerificationCodeScreenSubmittingPreview() {
+  Previews.Preview {
+    VerificationCodeScreen(
+      state = VerificationCodeState(
+        e164 = "+1 555-123-4567",
+        isSubmittingCode = true
+      ),
       onEvent = {}
     )
   }

feature/registration/src/main/java/org/signal/registration/screens/verificationcode/VerificationCodeScreenEvents.kt

@@ -12,4 +12,9 @@ sealed class VerificationCodeScreenEvents {
   data object CallMe : VerificationCodeScreenEvents()
   data object HavingTrouble : VerificationCodeScreenEvents()
   data object ConsumeInnerOneTimeEvent : VerificationCodeScreenEvents()
+
+  /**
+   * Event to update countdown timers. Should be triggered periodically (e.g., every second).
+   */
+  data object CountdownTick : VerificationCodeScreenEvents()
 }

feature/registration/src/main/java/org/signal/registration/screens/verificationcode/VerificationCodeState.kt

@@ -7,10 +7,14 @@ package org.signal.registration.screens.verificationcode
 
 import org.signal.registration.NetworkController.SessionMetadata
 import kotlin.time.Duration
+import kotlin.time.Duration.Companion.seconds
 
 data class VerificationCodeState(
   val sessionMetadata: SessionMetadata? = null,
   val e164: String = "",
+  val isSubmittingCode: Boolean = false,
+  val rateLimits: SmsAndCallRateLimits = SmsAndCallRateLimits(),
+  val incorrectCodeAttempts: Int = 0,
   val oneTimeEvent: OneTimeEvent? = null
 ) {
   sealed interface OneTimeEvent {
@@ -22,4 +26,28 @@ data class VerificationCodeState(
     data object IncorrectVerificationCode : OneTimeEvent
     data object RegistrationError : OneTimeEvent
   }
+
+  /**
+   * Returns true if the user can resend SMS (timer has expired)
+   */
+  fun canResendSms(): Boolean = rateLimits.smsResendTimeRemaining <= 0.seconds
+
+  /**
+   * Returns true if the user can request a call (timer has expired)
+   */
+  fun canRequestCall(): Boolean = rateLimits.callRequestTimeRemaining <= 0.seconds
+
+  /**
+   * Returns true if the "Having Trouble" button should be shown.
+   * Matches the old behavior of showing after 3 incorrect code attempts.
+   */
+  fun shouldShowHavingTrouble(): Boolean = incorrectCodeAttempts >= 3
 }
+
+/**
+ * Rate limit data for SMS resend and phone call request countdown timers.
+ */
+data class SmsAndCallRateLimits(
+  val smsResendTimeRemaining: Duration = 0.seconds,
+  val callRequestTimeRemaining: Duration = 0.seconds
+)

feature/registration/src/main/java/org/signal/registration/screens/verificationcode/VerificationCodeViewModel.kt

@@ -25,11 +25,15 @@ import org.signal.registration.RegistrationRoute
 import org.signal.registration.screens.util.navigateBack
 import org.signal.registration.screens.util.navigateTo
 import org.signal.registration.screens.verificationcode.VerificationCodeState.OneTimeEvent
+import kotlin.time.Duration
+import kotlin.time.Duration.Companion.milliseconds
+import kotlin.time.Duration.Companion.seconds
 
 class VerificationCodeViewModel(
   private val repository: RegistrationRepository,
   private val parentState: StateFlow<RegistrationFlowState>,
-  private val parentEventEmitter: (RegistrationFlowEvent) -> Unit
+  private val parentEventEmitter: (RegistrationFlowEvent) -> Unit,
+  private val clock: () -> Long = { System.currentTimeMillis() }
 ) : ViewModel() {
 
   companion object {
@@ -39,24 +43,35 @@ class VerificationCodeViewModel(
   private val _localState = MutableStateFlow(VerificationCodeState())
   val state = combine(_localState, parentState) { state, parentState -> applyParentState(state, parentState) }
     .onEach { Log.d(TAG, "[State] $it") }
-    .stateIn(viewModelScope, SharingStarted.Eagerly, VerificationCodeState())
+    .stateIn(viewModelScope, SharingStarted.WhileSubscribed(5000), VerificationCodeState())
+
+  private var nextSmsAvailableAt: Duration = 0.seconds
+  private var nextCallAvailableAt: Duration = 0.seconds
 
   fun onEvent(event: VerificationCodeScreenEvents) {
     viewModelScope.launch {
-      _localState.emit(applyEvent(state.value, event))
+      val stateEmitter: (VerificationCodeState) -> Unit = { newState ->
+        _localState.value = newState
+      }
+      applyEvent(state.value, event, stateEmitter)
     }
   }
 
   @VisibleForTesting
-  suspend fun applyEvent(state: VerificationCodeState, event: VerificationCodeScreenEvents): VerificationCodeState {
+  suspend fun applyEvent(state: VerificationCodeState, event: VerificationCodeScreenEvents, stateEmitter: (VerificationCodeState) -> Unit) {
-    return when (event) {
+    val result = when (event) {
-      is VerificationCodeScreenEvents.CodeEntered -> transformCodeEntered(state, event.code)
+      is VerificationCodeScreenEvents.CodeEntered -> {
+        stateEmitter(state.copy(isSubmittingCode = true))
+        applyCodeEntered(state, event.code).copy(isSubmittingCode = false)
+      }
       is VerificationCodeScreenEvents.WrongNumber -> state.also { parentEventEmitter.navigateTo(RegistrationRoute.PhoneNumberEntry) }
-      is VerificationCodeScreenEvents.ResendSms -> transformResendCode(state, NetworkController.VerificationCodeTransport.SMS)
+      is VerificationCodeScreenEvents.ResendSms -> applyResendCode(state, NetworkController.VerificationCodeTransport.SMS)
-      is VerificationCodeScreenEvents.CallMe -> transformResendCode(state, NetworkController.VerificationCodeTransport.VOICE)
+      is VerificationCodeScreenEvents.CallMe -> applyResendCode(state, NetworkController.VerificationCodeTransport.VOICE)
       is VerificationCodeScreenEvents.HavingTrouble -> throw NotImplementedError("having trouble flow") // TODO [registration] - Having trouble flow
       is VerificationCodeScreenEvents.ConsumeInnerOneTimeEvent -> state.copy(oneTimeEvent = null)
+      is VerificationCodeScreenEvents.CountdownTick -> applyCountdownTick(state)
     }
+    stateEmitter(result)
   }
 
   @VisibleForTesting
@@ -67,15 +82,38 @@ class VerificationCodeViewModel(
       return state
     }
 
+    val sessionChanged = state.sessionMetadata?.id != parentState.sessionMetadata.id
+
+    val rateLimits = if (sessionChanged) {
+      computeRateLimits(parentState.sessionMetadata)
+    } else {
+      state.rateLimits
+    }
+
     return state.copy(
       sessionMetadata = parentState.sessionMetadata,
-      e164 = parentState.sessionE164
+      e164 = parentState.sessionE164,
+      rateLimits = rateLimits
     )
   }
 
-  private suspend fun transformCodeEntered(inputState: VerificationCodeState, code: String): VerificationCodeState {
+  /**
-    var state = inputState.copy()
+   * Decrements countdown timers by 1 second, ensuring they don't go below 0.
-    var sessionMetadata = state.sessionMetadata ?: return state.also { parentEventEmitter(RegistrationFlowEvent.ResetState) }
+   */
+  private fun applyCountdownTick(state: VerificationCodeState): VerificationCodeState {
+    return state.copy(
+      rateLimits = SmsAndCallRateLimits(
+        smsResendTimeRemaining = (state.rateLimits.smsResendTimeRemaining - 1.seconds).coerceAtLeast(0.seconds),
+        callRequestTimeRemaining = (state.rateLimits.callRequestTimeRemaining - 1.seconds).coerceAtLeast(0.seconds)
+      )
+    )
+  }
+
+  private suspend fun applyCodeEntered(inputState: VerificationCodeState, code: String): VerificationCodeState {
+    var state = inputState
+    var sessionMetadata = state.sessionMetadata ?: return state.also {
+      parentEventEmitter(RegistrationFlowEvent.ResetState)
+    }
 
     // TODO should we be checking on whether we need to do more captcha stuff?
 
@@ -89,7 +127,8 @@ class VerificationCodeViewModel(
         when (result.error) {
           is NetworkController.SubmitVerificationCodeError.InvalidSessionIdOrVerificationCode -> {
             Log.w(TAG, "[SubmitCode] Invalid sessionId or verification code entered. This is distinct from an *incorrect* verification code. Body: ${result.error.message}")
-            return state.copy(oneTimeEvent = OneTimeEvent.IncorrectVerificationCode)
+            val newAttempts = state.incorrectCodeAttempts + 1
+            return state.copy(oneTimeEvent = OneTimeEvent.IncorrectVerificationCode, incorrectCodeAttempts = newAttempts)
           }
           is NetworkController.SubmitVerificationCodeError.SessionNotFound -> {
             Log.w(TAG, "[SubmitCode] Session not found: ${result.error.message}")
@@ -114,6 +153,7 @@ class VerificationCodeViewModel(
         }
       }
       is NetworkController.RegistrationNetworkResult.NetworkError -> {
+        Log.w(TAG, "[SubmitCode] Network error.", result.exception)
         return state.copy(oneTimeEvent = OneTimeEvent.NetworkError)
       }
       is NetworkController.RegistrationNetworkResult.ApplicationError -> {
@@ -126,7 +166,8 @@ class VerificationCodeViewModel(
 
     if (!sessionMetadata.verified) {
       Log.w(TAG, "[SubmitCode] Verification code was incorrect.")
-      return state.copy(oneTimeEvent = OneTimeEvent.IncorrectVerificationCode)
+      val newAttempts = state.incorrectCodeAttempts + 1
+      return state.copy(oneTimeEvent = OneTimeEvent.IncorrectVerificationCode, incorrectCodeAttempts = newAttempts)
     }
 
     // Attempt to register
@@ -192,68 +233,103 @@ class VerificationCodeViewModel(
     }
   }
 
-  private suspend fun transformResendCode(
+  private suspend fun applyResendCode(
-    inputState: VerificationCodeState,
+    state: VerificationCodeState,
     transport: NetworkController.VerificationCodeTransport
   ): VerificationCodeState {
-    val state = inputState.copy()
     if (state.sessionMetadata == null) {
       parentEventEmitter(RegistrationFlowEvent.ResetState)
-      return inputState
+      return state
     }
 
-    val sessionMetadata = state.sessionMetadata
-
     val result = repository.requestVerificationCode(
-      sessionId = sessionMetadata.id,
+      sessionId = state.sessionMetadata.id,
       smsAutoRetrieveCodeSupported = false,
       transport = transport
     )
 
     return when (result) {
       is NetworkController.RegistrationNetworkResult.Success -> {
-        state.copy(sessionMetadata = result.data)
+        Log.i(TAG, "[RequestCode][$transport] Successfully requested verification code.")
+        parentEventEmitter(RegistrationFlowEvent.SessionUpdated(result.data))
+        state.copy(
+          sessionMetadata = result.data,
+          rateLimits = computeRateLimits(result.data)
+        )
       }
       is NetworkController.RegistrationNetworkResult.Failure -> {
         when (result.error) {
           is NetworkController.RequestVerificationCodeError.InvalidRequest -> {
+            Log.w(TAG, "[RequestCode][$transport] Invalid request: ${result.error.message}")
             state.copy(oneTimeEvent = OneTimeEvent.UnknownError)
           }
           is NetworkController.RequestVerificationCodeError.RateLimited -> {
-            state.copy(oneTimeEvent = OneTimeEvent.RateLimited(result.error.retryAfter))
+            Log.w(TAG, "[RequestCode][$transport] Rate limited (retryAfter: ${result.error.retryAfter}).")
+            parentEventEmitter(RegistrationFlowEvent.SessionUpdated(result.error.session))
+            state.copy(
+              oneTimeEvent = OneTimeEvent.RateLimited(result.error.retryAfter),
+              sessionMetadata = result.error.session,
+              rateLimits = computeRateLimits(result.error.session)
+            )
           }
           is NetworkController.RequestVerificationCodeError.CouldNotFulfillWithRequestedTransport -> {
-            state.copy(oneTimeEvent = OneTimeEvent.CouldNotRequestCodeWithSelectedTransport)
+            Log.w(TAG, "[RequestCode][$transport] Could not fulfill with requested transport.")
+            parentEventEmitter(RegistrationFlowEvent.SessionUpdated(result.error.session))
+            state.copy(
+              oneTimeEvent = OneTimeEvent.CouldNotRequestCodeWithSelectedTransport,
+              sessionMetadata = result.error.session,
+              rateLimits = computeRateLimits(result.error.session)
+            )
           }
           is NetworkController.RequestVerificationCodeError.InvalidSessionId -> {
+            Log.w(TAG, "[RequestCode][$transport] Invalid session ID: ${result.error.message}")
             // TODO don't start over, go back to phone number entry
             parentEventEmitter(RegistrationFlowEvent.ResetState)
             state
           }
           is NetworkController.RequestVerificationCodeError.MissingRequestInformationOrAlreadyVerified -> {
-            Log.w(TAG, "When requesting verification code, missing request information or already verified.")
+            Log.w(TAG, "[RequestCode][$transport] Missing request information or already verified.")
-            state.copy(oneTimeEvent = OneTimeEvent.NetworkError)
+            parentEventEmitter(RegistrationFlowEvent.SessionUpdated(result.error.session))
+            state.copy(
+              oneTimeEvent = OneTimeEvent.NetworkError,
+              sessionMetadata = result.error.session,
+              rateLimits = computeRateLimits(result.error.session)
+            )
           }
           is NetworkController.RequestVerificationCodeError.SessionNotFound -> {
+            Log.w(TAG, "[RequestCode][$transport] Session not found: ${result.error.message}")
             // TODO don't start over, go back to phone number entry
             parentEventEmitter(RegistrationFlowEvent.ResetState)
             state
           }
           is NetworkController.RequestVerificationCodeError.ThirdPartyServiceError -> {
+            Log.w(TAG, "[RequestCode][$transport] Third party service error. ${result.error.data}")
             state.copy(oneTimeEvent = OneTimeEvent.ThirdPartyError)
           }
         }
       }
       is NetworkController.RegistrationNetworkResult.NetworkError -> {
+        Log.w(TAG, "[RequestCode][$transport] Network error.", result.exception)
         state.copy(oneTimeEvent = OneTimeEvent.NetworkError)
       }
       is NetworkController.RegistrationNetworkResult.ApplicationError -> {
-        Log.w(TAG, "Unknown error when requesting verification code.", result.exception)
+        Log.w(TAG, "[RequestCode][$transport] Unknown application error.", result.exception)
         state.copy(oneTimeEvent = OneTimeEvent.UnknownError)
       }
     }
   }
 
+  private fun computeRateLimits(session: NetworkController.SessionMetadata): SmsAndCallRateLimits {
+    val now = clock().milliseconds
+    nextSmsAvailableAt = now + (session.nextSms?.seconds ?: nextSmsAvailableAt)
+    nextCallAvailableAt = now + (session.nextCall?.seconds ?: nextCallAvailableAt)
+
+    return SmsAndCallRateLimits(
+      smsResendTimeRemaining = (nextSmsAvailableAt - clock().milliseconds).coerceAtLeast(0.seconds),
+      callRequestTimeRemaining = (nextCallAvailableAt - clock().milliseconds).coerceAtLeast(0.seconds)
+    )
+  }
+
   class Factory(
     private val repository: RegistrationRepository,
     private val parentState: StateFlow<RegistrationFlowState>,

feature/registration/src/main/java/org/signal/registration/test/TestTags.kt

@@ -41,4 +41,5 @@ object TestTags {
   const val VERIFICATION_CODE_WRONG_NUMBER_BUTTON = "verification_code_wrong_number_button"
   const val VERIFICATION_CODE_RESEND_SMS_BUTTON = "verification_code_resend_sms_button"
   const val VERIFICATION_CODE_CALL_ME_BUTTON = "verification_code_call_me_button"
+  const val VERIFICATION_CODE_HAVING_TROUBLE_BUTTON = "verification_code_having_trouble_button"
 }

feature/registration/src/main/res/values/strings.xml

@@ -33,6 +33,16 @@
     <!-- Storage permission row description -->
     <string name="GrantPermissionsFragment__send_photos_videos_and_files">Send photos, videos and files from your device.</string>
 
+    <!-- PhoneNumberEntryScreen -->
+    <!-- Title of registration screen when asking for the users phone number -->
+    <string name="RegistrationActivity_phone_number">Phone number</string>
+    <!-- Text explaining to users that they will be receiving a verification for their phone number and that carrier rates could apply -->
+    <string name="RegistrationActivity_you_will_receive_a_verification_code">You will receive a verification code. Carrier rates may apply.</string>
+    <!-- Hint text to select a country -->
+    <string name="RegistrationActivity_select_a_country">Select a country</string>
+    <string name="RegistrationActivity_phone_number_description">Phone number</string>
+    <string name="RegistrationActivity_next">Next</string>
+
     <!-- CountryCodePickerScreen -->
     <!-- Title of the country code selection screen -->
     <string name="CountryCodeSelectScreen__your_country">Your country</string>
@@ -42,4 +52,36 @@
     <string name="CountryCodeSelectScreen__search_by">Search by name or number</string>
     <!-- Fallback text for countries with no name -->
     <string name="CountryCodeSelectScreen__unknown_country">Unknown country</string>
+
+    <!-- VerificationCodeScreen -->
+    <!-- Title of the verification code entry screen -->
+    <string name="VerificationCodeScreen__verification_code">Verification code</string>
+    <!-- Subtitle explaining where the code was sent. Placeholder is the phone number -->
+    <string name="VerificationCodeScreen__enter_the_code_we_sent_to_s">Enter the code we sent to %s</string>
+    <!-- Button text for wrong number action -->
+    <string name="VerificationCodeScreen__wrong_number">Wrong number?</string>
+    <!-- Button text for resend SMS action -->
+    <string name="VerificationCodeScreen__resend_code">Resend Code</string>
+    <!-- Button text for call me action -->
+    <string name="VerificationCodeScreen__call_me_instead">Call me instead</string>
+    <!-- Countdown text shown below the resend code button. Placeholders are minutes and seconds -->
+    <string name="VerificationCodeScreen__countdown_format">(%1$02d:%2$02d)</string>
+    <!-- Button text for call me when countdown is active. Placeholders are minutes and seconds -->
+    <string name="VerificationCodeScreen__call_me_available_in">Call me (%1$02d:%2$02d)</string>
+    <!-- Toast shown when the user enters an incorrect verification code -->
+    <string name="VerificationCodeScreen__incorrect_code">Incorrect code</string>
+    <!-- Snackbar shown when there is a network error -->
+    <string name="VerificationCodeScreen__network_error">Unable to connect. Please check your network and try again.</string>
+    <!-- Snackbar shown when rate limited. Placeholder is the retry duration -->
+    <string name="VerificationCodeScreen__too_many_attempts_try_again_in_s">Too many attempts. Try again in %s.</string>
+    <!-- Snackbar shown for generic/unknown errors -->
+    <string name="VerificationCodeScreen__an_unexpected_error_occurred">An unexpected error occurred. Please try again.</string>
+    <!-- Snackbar shown when the SMS provider has an error -->
+    <string name="VerificationCodeScreen__sms_provider_error">There was a problem sending your verification code. Please try again.</string>
+    <!-- Snackbar shown when the selected transport (SMS/voice) is unavailable -->
+    <string name="VerificationCodeScreen__could_not_send_code_via_selected_method">Could not send code via the selected method. Please try another option.</string>
+    <!-- Snackbar shown for registration errors -->
+    <string name="VerificationCodeScreen__registration_error">Registration failed. Please try again.</string>
+    <!-- Button text for having trouble with verification -->
+    <string name="VerificationCodeScreen__having_trouble">Having trouble?</string>
 </resources>

feature/registration/src/test/java/org/signal/registration/screens/phonenumber/PhoneNumberEntryViewModelTest.kt

@@ -288,8 +288,8 @@ class PhoneNumberEntryViewModelTest {
     viewModel.applyEvent(initialState, PhoneNumberEntryScreenEvents.PhoneNumberSubmitted, stateEmitter, parentEventEmitter)
 
     // Verify spinner states
-    assertThat(emittedStates.first().showFullScreenSpinner).isTrue()
+    assertThat(emittedStates.first().showSpinner).isTrue()
-    assertThat(emittedStates.last().showFullScreenSpinner).isFalse()
+    assertThat(emittedStates.last().showSpinner).isFalse()
 
     assertThat(emittedStates.last().sessionMetadata).isNotNull()
     assertThat(emittedEvents).hasSize(1)
@@ -314,8 +314,8 @@ class PhoneNumberEntryViewModelTest {
     viewModel.applyEvent(initialState, PhoneNumberEntryScreenEvents.PhoneNumberSubmitted, stateEmitter, parentEventEmitter)
 
     // Verify spinner states
-    assertThat(emittedStates.first().showFullScreenSpinner).isTrue()
+    assertThat(emittedStates.first().showSpinner).isTrue()
-    assertThat(emittedStates.last().showFullScreenSpinner).isFalse()
+    assertThat(emittedStates.last().showSpinner).isFalse()
 
     assertThat(emittedEvents).hasSize(1)
     assertThat(emittedEvents.first())
@@ -339,8 +339,8 @@ class PhoneNumberEntryViewModelTest {
     viewModel.applyEvent(initialState, PhoneNumberEntryScreenEvents.PhoneNumberSubmitted, stateEmitter, parentEventEmitter)
 
     // Verify spinner states
-    assertThat(emittedStates.first().showFullScreenSpinner).isTrue()
+    assertThat(emittedStates.first().showSpinner).isTrue()
-    assertThat(emittedStates.last().showFullScreenSpinner).isFalse()
+    assertThat(emittedStates.last().showSpinner).isFalse()
 
     assertThat(emittedStates.last().oneTimeEvent).isNotNull()
       .isInstanceOf<PhoneNumberEntryState.OneTimeEvent.RateLimited>()
@@ -363,8 +363,8 @@ class PhoneNumberEntryViewModelTest {
     viewModel.applyEvent(initialState, PhoneNumberEntryScreenEvents.PhoneNumberSubmitted, stateEmitter, parentEventEmitter)
 
     // Verify spinner states
-    assertThat(emittedStates.first().showFullScreenSpinner).isTrue()
+    assertThat(emittedStates.first().showSpinner).isTrue()
-    assertThat(emittedStates.last().showFullScreenSpinner).isFalse()
+    assertThat(emittedStates.last().showSpinner).isFalse()
 
     assertThat(emittedStates.last().oneTimeEvent).isEqualTo(PhoneNumberEntryState.OneTimeEvent.UnknownError)
   }
@@ -382,8 +382,8 @@ class PhoneNumberEntryViewModelTest {
     viewModel.applyEvent(initialState, PhoneNumberEntryScreenEvents.PhoneNumberSubmitted, stateEmitter, parentEventEmitter)
 
     // Verify spinner states
-    assertThat(emittedStates.first().showFullScreenSpinner).isTrue()
+    assertThat(emittedStates.first().showSpinner).isTrue()
-    assertThat(emittedStates.last().showFullScreenSpinner).isFalse()
+    assertThat(emittedStates.last().showSpinner).isFalse()
 
     assertThat(emittedStates.last().oneTimeEvent).isEqualTo(PhoneNumberEntryState.OneTimeEvent.NetworkError)
   }
@@ -401,8 +401,8 @@ class PhoneNumberEntryViewModelTest {
     viewModel.applyEvent(initialState, PhoneNumberEntryScreenEvents.PhoneNumberSubmitted, stateEmitter, parentEventEmitter)
 
     // Verify spinner states
-    assertThat(emittedStates.first().showFullScreenSpinner).isTrue()
+    assertThat(emittedStates.first().showSpinner).isTrue()
-    assertThat(emittedStates.last().showFullScreenSpinner).isFalse()
+    assertThat(emittedStates.last().showSpinner).isFalse()
 
     assertThat(emittedStates.last().oneTimeEvent).isEqualTo(PhoneNumberEntryState.OneTimeEvent.UnknownError)
   }
@@ -422,8 +422,8 @@ class PhoneNumberEntryViewModelTest {
     viewModel.applyEvent(initialState, PhoneNumberEntryScreenEvents.PhoneNumberSubmitted, stateEmitter, parentEventEmitter)
 
     // Verify spinner states
-    assertThat(emittedStates.first().showFullScreenSpinner).isTrue()
+    assertThat(emittedStates.first().showSpinner).isTrue()
-    assertThat(emittedStates.last().showFullScreenSpinner).isFalse()
+    assertThat(emittedStates.last().showSpinner).isFalse()
 
     // Should not create a new session, just request verification code
     assertThat(emittedEvents).hasSize(1)
@@ -452,8 +452,8 @@ class PhoneNumberEntryViewModelTest {
     viewModel.applyEvent(initialState, PhoneNumberEntryScreenEvents.PhoneNumberSubmitted, stateEmitter, parentEventEmitter)
 
     // Verify spinner states
-    assertThat(emittedStates.first().showFullScreenSpinner).isTrue()
+    assertThat(emittedStates.first().showSpinner).isTrue()
-    assertThat(emittedStates.last().showFullScreenSpinner).isFalse()
+    assertThat(emittedStates.last().showSpinner).isFalse()
 
     assertThat(emittedStates.last().oneTimeEvent).isNotNull().isInstanceOf<PhoneNumberEntryState.OneTimeEvent.RateLimited>()
   }
@@ -477,8 +477,8 @@ class PhoneNumberEntryViewModelTest {
     viewModel.applyEvent(initialState, PhoneNumberEntryScreenEvents.PhoneNumberSubmitted, stateEmitter, parentEventEmitter)
 
     // Verify spinner states
-    assertThat(emittedStates.first().showFullScreenSpinner).isTrue()
+    assertThat(emittedStates.first().showSpinner).isTrue()
-    assertThat(emittedStates.last().showFullScreenSpinner).isFalse()
+    assertThat(emittedStates.last().showSpinner).isFalse()
 
     assertThat(emittedEvents).hasSize(1)
     assertThat(emittedEvents.first()).isEqualTo(RegistrationFlowEvent.ResetState)
@@ -503,8 +503,8 @@ class PhoneNumberEntryViewModelTest {
     viewModel.applyEvent(initialState, PhoneNumberEntryScreenEvents.PhoneNumberSubmitted, stateEmitter, parentEventEmitter)
 
     // Verify spinner states
-    assertThat(emittedStates.first().showFullScreenSpinner).isTrue()
+    assertThat(emittedStates.first().showSpinner).isTrue()
-    assertThat(emittedStates.last().showFullScreenSpinner).isFalse()
+    assertThat(emittedStates.last().showSpinner).isFalse()
 
     assertThat(emittedStates.last().oneTimeEvent).isEqualTo(PhoneNumberEntryState.OneTimeEvent.CouldNotRequestCodeWithSelectedTransport)
   }
@@ -530,8 +530,8 @@ class PhoneNumberEntryViewModelTest {
     viewModel.applyEvent(initialState, PhoneNumberEntryScreenEvents.PhoneNumberSubmitted, stateEmitter, parentEventEmitter)
 
     // Verify spinner states
-    assertThat(emittedStates.first().showFullScreenSpinner).isTrue()
+    assertThat(emittedStates.first().showSpinner).isTrue()
-    assertThat(emittedStates.last().showFullScreenSpinner).isFalse()
+    assertThat(emittedStates.last().showSpinner).isFalse()
 
     assertThat(emittedStates.last().oneTimeEvent).isEqualTo(PhoneNumberEntryState.OneTimeEvent.ThirdPartyError)
   }
@@ -559,8 +559,8 @@ class PhoneNumberEntryViewModelTest {
     viewModel.applyEvent(initialState, PhoneNumberEntryScreenEvents.PhoneNumberSubmitted, stateEmitter, parentEventEmitter)
 
     // Verify spinner states
-    assertThat(emittedStates.first().showFullScreenSpinner).isTrue()
+    assertThat(emittedStates.first().showSpinner).isTrue()
-    assertThat(emittedStates.last().showFullScreenSpinner).isFalse()
+    assertThat(emittedStates.last().showSpinner).isFalse()
 
     // Verify navigation to verification code entry
     assertThat(emittedEvents).hasSize(1)
@@ -591,8 +591,8 @@ class PhoneNumberEntryViewModelTest {
     viewModel.applyEvent(initialState, PhoneNumberEntryScreenEvents.PhoneNumberSubmitted, stateEmitter, parentEventEmitter)
 
     // Verify spinner states
-    assertThat(emittedStates.first().showFullScreenSpinner).isTrue()
+    assertThat(emittedStates.first().showSpinner).isTrue()
-    assertThat(emittedStates.last().showFullScreenSpinner).isFalse()
+    assertThat(emittedStates.last().showSpinner).isFalse()
 
     // Verify navigation continues despite no push challenge token
     assertThat(emittedEvents).hasSize(1)
@@ -627,8 +627,8 @@ class PhoneNumberEntryViewModelTest {
     viewModel.applyEvent(initialState, PhoneNumberEntryScreenEvents.PhoneNumberSubmitted, stateEmitter, parentEventEmitter)
 
     // Verify spinner states
-    assertThat(emittedStates.first().showFullScreenSpinner).isTrue()
+    assertThat(emittedStates.first().showSpinner).isTrue()
-    assertThat(emittedStates.last().showFullScreenSpinner).isFalse()
+    assertThat(emittedStates.last().showSpinner).isFalse()
 
     // Verify navigation continues despite push challenge submission failure
     assertThat(emittedEvents).hasSize(1)
@@ -658,8 +658,8 @@ class PhoneNumberEntryViewModelTest {
     viewModel.applyEvent(initialState, PhoneNumberEntryScreenEvents.PhoneNumberSubmitted, stateEmitter, parentEventEmitter)
 
     // Verify spinner states
-    assertThat(emittedStates.first().showFullScreenSpinner).isTrue()
+    assertThat(emittedStates.first().showSpinner).isTrue()
-    assertThat(emittedStates.last().showFullScreenSpinner).isFalse()
+    assertThat(emittedStates.last().showSpinner).isFalse()
 
     // Verify navigation continues despite network error
     assertThat(emittedEvents).hasSize(1)
@@ -689,8 +689,8 @@ class PhoneNumberEntryViewModelTest {
     viewModel.applyEvent(initialState, PhoneNumberEntryScreenEvents.PhoneNumberSubmitted, stateEmitter, parentEventEmitter)
 
     // Verify spinner states
-    assertThat(emittedStates.first().showFullScreenSpinner).isTrue()
+    assertThat(emittedStates.first().showSpinner).isTrue()
-    assertThat(emittedStates.last().showFullScreenSpinner).isFalse()
+    assertThat(emittedStates.last().showSpinner).isFalse()
 
     // Verify navigation continues despite application error
     assertThat(emittedEvents).hasSize(1)
@@ -719,8 +719,8 @@ class PhoneNumberEntryViewModelTest {
     viewModel.applyEvent(initialState, PhoneNumberEntryScreenEvents.PhoneNumberSubmitted, stateEmitter, parentEventEmitter)
 
     // Verify spinner states
-    assertThat(emittedStates.first().showFullScreenSpinner).isTrue()
+    assertThat(emittedStates.first().showSpinner).isTrue()
-    assertThat(emittedStates.last().showFullScreenSpinner).isFalse()
+    assertThat(emittedStates.last().showSpinner).isFalse()
 
     // Verify navigation to captcha
     assertThat(emittedEvents).hasSize(1)

feature/registration/src/test/java/org/signal/registration/screens/verificationcode/VerificationCodeScreenTest.kt

@@ -49,7 +49,7 @@ class VerificationCodeScreenTest {
     }
 
     // Then
-    composeTestRule.onNodeWithText("Enter verification code").assertIsDisplayed()
+    composeTestRule.onNodeWithText("Verification code").assertIsDisplayed()
   }
 
   @Test
@@ -70,7 +70,7 @@ class VerificationCodeScreenTest {
     composeTestRule.onNodeWithTag(TestTags.VERIFICATION_CODE_DIGIT_2).assertIsDisplayed()
     composeTestRule.onNodeWithTag(TestTags.VERIFICATION_CODE_DIGIT_3).assertIsDisplayed()
     composeTestRule.onNodeWithTag(TestTags.VERIFICATION_CODE_DIGIT_4).assertIsDisplayed()
-    composeTestRule.onNodeWithTag(TestTags.VERIFICATION_CODE_DIGIT_5).assertIsDisplayed()
+    composeTestRule.onNodeWithTag(TestTags.VERIFICATION_CODE_DIGIT_5).fetchSemanticsNode()
   }
 
   @Test
@@ -191,7 +191,7 @@ class VerificationCodeScreenTest {
 
     // Then
     composeTestRule.onNodeWithText("Wrong number?").assertIsDisplayed()
-    composeTestRule.onNodeWithText("Resend SMS").assertIsDisplayed()
+    composeTestRule.onNodeWithText("Resend Code").assertIsDisplayed()
     composeTestRule.onNodeWithText("Call me instead").assertIsDisplayed()
   }
 }

feature/registration/src/test/java/org/signal/registration/screens/verificationcode/VerificationCodeViewModelTest.kt

@@ -11,6 +11,7 @@ import assertk.assertions.isEqualTo
 import assertk.assertions.isInstanceOf
 import assertk.assertions.isNotNull
 import assertk.assertions.isNull
+import assertk.assertions.isTrue
 import assertk.assertions.prop
 import io.mockk.coEvery
 import io.mockk.mockk
@@ -34,6 +35,8 @@ class VerificationCodeViewModelTest {
   private lateinit var parentState: MutableStateFlow<RegistrationFlowState>
   private lateinit var emittedEvents: MutableList<RegistrationFlowEvent>
   private lateinit var parentEventEmitter: (RegistrationFlowEvent) -> Unit
+  private lateinit var emittedStates: MutableList<VerificationCodeState>
+  private lateinit var stateEmitter: (VerificationCodeState) -> Unit
 
   @Before
   fun setup() {
@@ -47,6 +50,8 @@ class VerificationCodeViewModelTest {
     )
     emittedEvents = mutableListOf()
     parentEventEmitter = { event -> emittedEvents.add(event) }
+    emittedStates = mutableListOf()
+    stateEmitter = { state -> emittedStates.add(state) }
     viewModel = VerificationCodeViewModel(mockRepository, parentState, parentEventEmitter)
   }
 
@@ -133,24 +138,26 @@ class VerificationCodeViewModelTest {
       oneTimeEvent = VerificationCodeState.OneTimeEvent.NetworkError
     )
 
-    val result = viewModel.applyEvent(
+    viewModel.applyEvent(
       initialState,
-      VerificationCodeScreenEvents.ConsumeInnerOneTimeEvent
+      VerificationCodeScreenEvents.ConsumeInnerOneTimeEvent,
+      stateEmitter
     )
 
-    assertThat(result.oneTimeEvent).isNull()
+    assertThat(emittedStates.last().oneTimeEvent).isNull()
   }
 
   @Test
   fun `ConsumeInnerOneTimeEvent with null event returns state with null event`() = runTest {
     val initialState = VerificationCodeState(oneTimeEvent = null)
 
-    val result = viewModel.applyEvent(
+    viewModel.applyEvent(
       initialState,
-      VerificationCodeScreenEvents.ConsumeInnerOneTimeEvent
+      VerificationCodeScreenEvents.ConsumeInnerOneTimeEvent,
+      stateEmitter
     )
 
-    assertThat(result.oneTimeEvent).isNull()
+    assertThat(emittedStates.last().oneTimeEvent).isNull()
   }
 
   // ==================== applyEvent: WrongNumber Tests ====================
@@ -159,7 +166,7 @@ class VerificationCodeViewModelTest {
   fun `WrongNumber navigates to PhoneNumberEntry`() = runTest {
     val initialState = VerificationCodeState()
 
-    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.WrongNumber)
+    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.WrongNumber, stateEmitter)
 
     assertThat(emittedEvents).hasSize(1)
     assertThat(emittedEvents.first())
@@ -170,16 +177,42 @@ class VerificationCodeViewModelTest {
 
   // ==================== applyEvent: CodeEntered Tests ====================
 
+  @Test
+  fun `CodeEntered emits isSubmittingCode true then false`() = runTest {
+    val sessionMetadata = createSessionMetadata()
+    val initialState = VerificationCodeState(
+      sessionMetadata = sessionMetadata,
+      e164 = "+15551234567"
+    )
+
+    coEvery { mockRepository.submitVerificationCode(any(), any()) } returns
+      NetworkController.RegistrationNetworkResult.Failure(
+        NetworkController.SubmitVerificationCodeError.InvalidSessionIdOrVerificationCode("Wrong code")
+      )
+
+    viewModel.applyEvent(
+      initialState,
+      VerificationCodeScreenEvents.CodeEntered("123456"),
+      stateEmitter
+    )
+
+    // First emitted state should have isSubmittingCode = true
+    assertThat(emittedStates.first().isSubmittingCode).isTrue()
+    // Final emitted state should have isSubmittingCode = false
+    assertThat(emittedStates.last().isSubmittingCode).isEqualTo(false)
+  }
+
   @Test
   fun `CodeEntered emits ResetState when sessionMetadata is null`() = runTest {
     val initialState = VerificationCodeState(sessionMetadata = null)
 
-    val result = viewModel.applyEvent(
+    viewModel.applyEvent(
       initialState,
-      VerificationCodeScreenEvents.CodeEntered("123456")
+      VerificationCodeScreenEvents.CodeEntered("123456"),
+      stateEmitter
     )
 
-    assertThat(result).isEqualTo(initialState)
+    assertThat(emittedStates.last()).isEqualTo(initialState)
     assertThat(emittedEvents).hasSize(1)
     assertThat(emittedEvents.first())
       .isInstanceOf<RegistrationFlowEvent.ResetState>()
@@ -201,7 +234,7 @@ class VerificationCodeViewModelTest {
     coEvery { mockRepository.registerAccountWithSession(any(), any(), any()) } returns
       NetworkController.RegistrationNetworkResult.Success(registerResponse to keyMaterial)
 
-    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.CodeEntered("123456"))
+    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.CodeEntered("123456"), stateEmitter)
 
     assertThat(emittedEvents).hasSize(2)
     assertThat(emittedEvents[0]).isInstanceOf<RegistrationFlowEvent.Registered>()
@@ -224,12 +257,13 @@ class VerificationCodeViewModelTest {
         NetworkController.SubmitVerificationCodeError.InvalidSessionIdOrVerificationCode("Wrong code")
       )
 
-    val result = viewModel.applyEvent(
+    viewModel.applyEvent(
       initialState,
-      VerificationCodeScreenEvents.CodeEntered("123456")
+      VerificationCodeScreenEvents.CodeEntered("123456"),
+      stateEmitter
     )
 
-    assertThat(result.oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.IncorrectVerificationCode)
+    assertThat(emittedStates.last().oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.IncorrectVerificationCode)
   }
 
   @Test
@@ -245,7 +279,7 @@ class VerificationCodeViewModelTest {
         NetworkController.SubmitVerificationCodeError.SessionNotFound("Session expired")
       )
 
-    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.CodeEntered("123456"))
+    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.CodeEntered("123456"), stateEmitter)
 
     assertThat(emittedEvents).hasSize(1)
     assertThat(emittedEvents.first()).isEqualTo(RegistrationFlowEvent.ResetState)
@@ -269,7 +303,7 @@ class VerificationCodeViewModelTest {
     coEvery { mockRepository.registerAccountWithSession(any(), any(), any()) } returns
       NetworkController.RegistrationNetworkResult.Success(registerResponse to keyMaterial)
 
-    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.CodeEntered("123456"))
+    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.CodeEntered("123456"), stateEmitter)
 
     assertThat(emittedEvents).hasSize(2)
     assertThat(emittedEvents[0]).isInstanceOf<RegistrationFlowEvent.Registered>()
@@ -292,7 +326,7 @@ class VerificationCodeViewModelTest {
         NetworkController.SubmitVerificationCodeError.SessionAlreadyVerifiedOrNoCodeRequested(unverifiedSession)
       )
 
-    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.CodeEntered("123456"))
+    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.CodeEntered("123456"), stateEmitter)
 
     assertThat(emittedEvents).hasSize(1)
     assertThat(emittedEvents.first()).isEqualTo(RegistrationFlowEvent.NavigateBack)
@@ -311,12 +345,13 @@ class VerificationCodeViewModelTest {
         NetworkController.SubmitVerificationCodeError.RateLimited(60.seconds, sessionMetadata)
       )
 
-    val result = viewModel.applyEvent(
+    viewModel.applyEvent(
       initialState,
-      VerificationCodeScreenEvents.CodeEntered("123456")
+      VerificationCodeScreenEvents.CodeEntered("123456"),
+      stateEmitter
     )
 
-    assertThat(result.oneTimeEvent).isNotNull()
+    assertThat(emittedStates.last().oneTimeEvent).isNotNull()
       .isInstanceOf<VerificationCodeState.OneTimeEvent.RateLimited>()
       .prop(VerificationCodeState.OneTimeEvent.RateLimited::retryAfter)
       .isEqualTo(60.seconds)
@@ -333,12 +368,13 @@ class VerificationCodeViewModelTest {
     coEvery { mockRepository.submitVerificationCode(any(), any()) } returns
       NetworkController.RegistrationNetworkResult.NetworkError(java.io.IOException("Network error"))
 
-    val result = viewModel.applyEvent(
+    viewModel.applyEvent(
       initialState,
-      VerificationCodeScreenEvents.CodeEntered("123456")
+      VerificationCodeScreenEvents.CodeEntered("123456"),
+      stateEmitter
     )
 
-    assertThat(result.oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.NetworkError)
+    assertThat(emittedStates.last().oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.NetworkError)
   }
 
   @Test
@@ -352,12 +388,13 @@ class VerificationCodeViewModelTest {
     coEvery { mockRepository.submitVerificationCode(any(), any()) } returns
       NetworkController.RegistrationNetworkResult.ApplicationError(RuntimeException("Unexpected"))
 
-    val result = viewModel.applyEvent(
+    viewModel.applyEvent(
       initialState,
-      VerificationCodeScreenEvents.CodeEntered("123456")
+      VerificationCodeScreenEvents.CodeEntered("123456"),
+      stateEmitter
     )
 
-    assertThat(result.oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.UnknownError)
+    assertThat(emittedStates.last().oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.UnknownError)
   }
 
   // ==================== applyEvent: CodeEntered - Registration Errors ====================
@@ -378,7 +415,7 @@ class VerificationCodeViewModelTest {
         NetworkController.RegisterAccountError.DeviceTransferPossible
       )
 
-    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.CodeEntered("123456"))
+    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.CodeEntered("123456"), stateEmitter)
 
     assertThat(emittedEvents).hasSize(1)
     assertThat(emittedEvents.first()).isEqualTo(RegistrationFlowEvent.ResetState)
@@ -400,12 +437,13 @@ class VerificationCodeViewModelTest {
         NetworkController.RegisterAccountError.RateLimited(30.seconds)
       )
 
-    val result = viewModel.applyEvent(
+    viewModel.applyEvent(
       initialState,
-      VerificationCodeScreenEvents.CodeEntered("123456")
+      VerificationCodeScreenEvents.CodeEntered("123456"),
+      stateEmitter
     )
 
-    assertThat(result.oneTimeEvent).isNotNull()
+    assertThat(emittedStates.last().oneTimeEvent).isNotNull()
       .isInstanceOf<VerificationCodeState.OneTimeEvent.RateLimited>()
       .prop(VerificationCodeState.OneTimeEvent.RateLimited::retryAfter)
       .isEqualTo(30.seconds)
@@ -427,12 +465,13 @@ class VerificationCodeViewModelTest {
         NetworkController.RegisterAccountError.InvalidRequest("Bad request")
       )
 
-    val result = viewModel.applyEvent(
+    viewModel.applyEvent(
       initialState,
-      VerificationCodeScreenEvents.CodeEntered("123456")
+      VerificationCodeScreenEvents.CodeEntered("123456"),
+      stateEmitter
     )
 
-    assertThat(result.oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.RegistrationError)
+    assertThat(emittedStates.last().oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.RegistrationError)
   }
 
   @Ignore
@@ -451,12 +490,13 @@ class VerificationCodeViewModelTest {
         NetworkController.RegisterAccountError.RegistrationRecoveryPasswordIncorrect("Wrong password")
       )
 
-    val result = viewModel.applyEvent(
+    viewModel.applyEvent(
       initialState,
-      VerificationCodeScreenEvents.CodeEntered("123456")
+      VerificationCodeScreenEvents.CodeEntered("123456"),
+      stateEmitter
     )
 
-    assertThat(result.oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.RegistrationError)
+    assertThat(emittedStates.last().oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.RegistrationError)
   }
 
   @Ignore
@@ -473,12 +513,13 @@ class VerificationCodeViewModelTest {
     coEvery { mockRepository.registerAccountWithSession(any(), any(), any()) } returns
       NetworkController.RegistrationNetworkResult.NetworkError(java.io.IOException("Network error"))
 
-    val result = viewModel.applyEvent(
+    viewModel.applyEvent(
       initialState,
-      VerificationCodeScreenEvents.CodeEntered("123456")
+      VerificationCodeScreenEvents.CodeEntered("123456"),
+      stateEmitter
     )
 
-    assertThat(result.oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.NetworkError)
+    assertThat(emittedStates.last().oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.NetworkError)
   }
 
   @Ignore
@@ -495,12 +536,13 @@ class VerificationCodeViewModelTest {
     coEvery { mockRepository.registerAccountWithSession(any(), any(), any()) } returns
       NetworkController.RegistrationNetworkResult.ApplicationError(RuntimeException("Unexpected"))
 
-    val result = viewModel.applyEvent(
+    viewModel.applyEvent(
       initialState,
-      VerificationCodeScreenEvents.CodeEntered("123456")
+      VerificationCodeScreenEvents.CodeEntered("123456"),
+      stateEmitter
     )
 
-    assertThat(result.oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.UnknownError)
+    assertThat(emittedStates.last().oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.UnknownError)
   }
 
   // ==================== applyEvent: ResendSms Tests ====================
@@ -509,11 +551,11 @@ class VerificationCodeViewModelTest {
   fun `ResendSms with null sessionMetadata emits ResetState`() = runTest {
     val initialState = VerificationCodeState(sessionMetadata = null)
 
-    val result = viewModel.applyEvent(initialState, VerificationCodeScreenEvents.ResendSms)
+    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.ResendSms, stateEmitter)
 
     assertThat(emittedEvents).hasSize(1)
     assertThat(emittedEvents.first()).isEqualTo(RegistrationFlowEvent.ResetState)
-    assertThat(result).isEqualTo(initialState)
+    assertThat(emittedStates.last()).isEqualTo(initialState)
   }
 
   @Test
@@ -525,9 +567,9 @@ class VerificationCodeViewModelTest {
     coEvery { mockRepository.requestVerificationCode(any(), any(), eq(NetworkController.VerificationCodeTransport.SMS)) } returns
       NetworkController.RegistrationNetworkResult.Success(updatedSession)
 
-    val result = viewModel.applyEvent(initialState, VerificationCodeScreenEvents.ResendSms)
+    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.ResendSms, stateEmitter)
 
-    assertThat(result.sessionMetadata).isEqualTo(updatedSession)
+    assertThat(emittedStates.last().sessionMetadata).isEqualTo(updatedSession)
   }
 
   @Test
@@ -540,9 +582,9 @@ class VerificationCodeViewModelTest {
         NetworkController.RequestVerificationCodeError.RateLimited(45.seconds, sessionMetadata)
       )
 
-    val result = viewModel.applyEvent(initialState, VerificationCodeScreenEvents.ResendSms)
+    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.ResendSms, stateEmitter)
 
-    assertThat(result.oneTimeEvent).isNotNull()
+    assertThat(emittedStates.last().oneTimeEvent).isNotNull()
       .isInstanceOf<VerificationCodeState.OneTimeEvent.RateLimited>()
       .prop(VerificationCodeState.OneTimeEvent.RateLimited::retryAfter)
       .isEqualTo(45.seconds)
@@ -558,9 +600,9 @@ class VerificationCodeViewModelTest {
         NetworkController.RequestVerificationCodeError.InvalidRequest("Bad request")
       )
 
-    val result = viewModel.applyEvent(initialState, VerificationCodeScreenEvents.ResendSms)
+    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.ResendSms, stateEmitter)
 
-    assertThat(result.oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.UnknownError)
+    assertThat(emittedStates.last().oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.UnknownError)
   }
 
   @Test
@@ -573,9 +615,9 @@ class VerificationCodeViewModelTest {
         NetworkController.RequestVerificationCodeError.CouldNotFulfillWithRequestedTransport(sessionMetadata)
       )
 
-    val result = viewModel.applyEvent(initialState, VerificationCodeScreenEvents.ResendSms)
+    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.ResendSms, stateEmitter)
 
-    assertThat(result.oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.CouldNotRequestCodeWithSelectedTransport)
+    assertThat(emittedStates.last().oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.CouldNotRequestCodeWithSelectedTransport)
   }
 
   @Test
@@ -588,7 +630,7 @@ class VerificationCodeViewModelTest {
         NetworkController.RequestVerificationCodeError.InvalidSessionId("Invalid session")
       )
 
-    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.ResendSms)
+    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.ResendSms, stateEmitter)
 
     assertThat(emittedEvents).hasSize(1)
     assertThat(emittedEvents.first()).isEqualTo(RegistrationFlowEvent.ResetState)
@@ -604,7 +646,7 @@ class VerificationCodeViewModelTest {
         NetworkController.RequestVerificationCodeError.SessionNotFound("Session not found")
       )
 
-    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.ResendSms)
+    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.ResendSms, stateEmitter)
 
     assertThat(emittedEvents).hasSize(1)
     assertThat(emittedEvents.first()).isEqualTo(RegistrationFlowEvent.ResetState)
@@ -620,9 +662,9 @@ class VerificationCodeViewModelTest {
         NetworkController.RequestVerificationCodeError.MissingRequestInformationOrAlreadyVerified(sessionMetadata)
       )
 
-    val result = viewModel.applyEvent(initialState, VerificationCodeScreenEvents.ResendSms)
+    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.ResendSms, stateEmitter)
 
-    assertThat(result.oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.NetworkError)
+    assertThat(emittedStates.last().oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.NetworkError)
   }
 
   @Test
@@ -637,9 +679,9 @@ class VerificationCodeViewModelTest {
         )
       )
 
-    val result = viewModel.applyEvent(initialState, VerificationCodeScreenEvents.ResendSms)
+    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.ResendSms, stateEmitter)
 
-    assertThat(result.oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.ThirdPartyError)
+    assertThat(emittedStates.last().oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.ThirdPartyError)
   }
 
   @Test
@@ -650,9 +692,9 @@ class VerificationCodeViewModelTest {
     coEvery { mockRepository.requestVerificationCode(any(), any(), eq(NetworkController.VerificationCodeTransport.SMS)) } returns
       NetworkController.RegistrationNetworkResult.NetworkError(java.io.IOException("Network error"))
 
-    val result = viewModel.applyEvent(initialState, VerificationCodeScreenEvents.ResendSms)
+    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.ResendSms, stateEmitter)
 
-    assertThat(result.oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.NetworkError)
+    assertThat(emittedStates.last().oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.NetworkError)
   }
 
   @Test
@@ -663,9 +705,9 @@ class VerificationCodeViewModelTest {
     coEvery { mockRepository.requestVerificationCode(any(), any(), eq(NetworkController.VerificationCodeTransport.SMS)) } returns
       NetworkController.RegistrationNetworkResult.ApplicationError(RuntimeException("Unexpected"))
 
-    val result = viewModel.applyEvent(initialState, VerificationCodeScreenEvents.ResendSms)
+    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.ResendSms, stateEmitter)
 
-    assertThat(result.oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.UnknownError)
+    assertThat(emittedStates.last().oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.UnknownError)
   }
 
   // ==================== applyEvent: CallMe Tests ====================
@@ -674,11 +716,11 @@ class VerificationCodeViewModelTest {
   fun `CallMe with null sessionMetadata emits ResetState`() = runTest {
     val initialState = VerificationCodeState(sessionMetadata = null)
 
-    val result = viewModel.applyEvent(initialState, VerificationCodeScreenEvents.CallMe)
+    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.CallMe, stateEmitter)
 
     assertThat(emittedEvents).hasSize(1)
     assertThat(emittedEvents.first()).isEqualTo(RegistrationFlowEvent.ResetState)
-    assertThat(result).isEqualTo(initialState)
+    assertThat(emittedStates.last()).isEqualTo(initialState)
   }
 
   @Test
@@ -690,9 +732,9 @@ class VerificationCodeViewModelTest {
     coEvery { mockRepository.requestVerificationCode(any(), any(), eq(NetworkController.VerificationCodeTransport.VOICE)) } returns
       NetworkController.RegistrationNetworkResult.Success(updatedSession)
 
-    val result = viewModel.applyEvent(initialState, VerificationCodeScreenEvents.CallMe)
+    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.CallMe, stateEmitter)
 
-    assertThat(result.sessionMetadata).isEqualTo(updatedSession)
+    assertThat(emittedStates.last().sessionMetadata).isEqualTo(updatedSession)
   }
 
   @Test
@@ -705,9 +747,9 @@ class VerificationCodeViewModelTest {
         NetworkController.RequestVerificationCodeError.RateLimited(90.seconds, sessionMetadata)
       )
 
-    val result = viewModel.applyEvent(initialState, VerificationCodeScreenEvents.CallMe)
+    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.CallMe, stateEmitter)
 
-    assertThat(result.oneTimeEvent).isNotNull()
+    assertThat(emittedStates.last().oneTimeEvent).isNotNull()
       .isInstanceOf<VerificationCodeState.OneTimeEvent.RateLimited>()
       .prop(VerificationCodeState.OneTimeEvent.RateLimited::retryAfter)
       .isEqualTo(90.seconds)
@@ -723,9 +765,9 @@ class VerificationCodeViewModelTest {
         NetworkController.RequestVerificationCodeError.CouldNotFulfillWithRequestedTransport(sessionMetadata)
       )
 
-    val result = viewModel.applyEvent(initialState, VerificationCodeScreenEvents.CallMe)
+    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.CallMe, stateEmitter)
 
-    assertThat(result.oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.CouldNotRequestCodeWithSelectedTransport)
+    assertThat(emittedStates.last().oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.CouldNotRequestCodeWithSelectedTransport)
   }
 
   @Test
@@ -740,9 +782,9 @@ class VerificationCodeViewModelTest {
         )
       )
 
-    val result = viewModel.applyEvent(initialState, VerificationCodeScreenEvents.CallMe)
+    viewModel.applyEvent(initialState, VerificationCodeScreenEvents.CallMe, stateEmitter)
 
-    assertThat(result.oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.ThirdPartyError)
+    assertThat(emittedStates.last().oneTimeEvent).isEqualTo(VerificationCodeState.OneTimeEvent.ThirdPartyError)
   }
 
   // ==================== Helper Functions ====================